Fermentations

Biosci Biotechnol Biochem, 2001 Dec, 65(12), 2755 - 62
Membrane-bound quinoprotein D-arabitol dehydrogenase of Gluconobacter suboxydans IFO 3257: a versatile enzyme for the oxidative fermentation of various ketoses; Adachi O et al.; Solubilization of membrane-bound quinoprotein D-arabitol dehydrogenase (ARDH) was done successfully with the membrane fraction of Gluconobacter suboxydans IFO 3257 . In enzyme solubilization and subsequent enzyme purification steps, special care was taken to purify ARDH as active as it was in the native membrane, after many disappointing trials . Selection of the best detergent, keeping ARDH as the holoenzyme by the addition of PQQ and Ca2+, and of a buffer system involving acetate buffer supplemented with Ca2+, were essential to treat the highly hydrophobic and thus labile enzyme . Purification of the enzyme was done by two steps of column chromatography on DEAE-Toyopearl and CM-Toyopearl in the presence of detergent and Ca2+ . ARDH was homogenous and showed a single sedimentation peak in analytical ultracentrifugation . ARDH was dissociated into two different subunits upon SDS-PAGE with molecular masses of 82 kDa (subunit I) and 14 kDa (subunit II), forming a heterodimeric structure . ARDH was proven to be a quinoprotein by detecting a liberated PQQ from SDS-treated ARDH in HPLC chromatography . More preliminarily, an EDTA-treated membrane fraction lost the enzyme activity and ARDH activity was restored to the original level by the addition of PQQ and Ca2+ . The most predominant unique character of ARDH, the substrate specificity, was highly versatile and many kinds of substrates were oxidized irreversibly by ARDH, not only pentitols but also other polyhydroxy alcohols including D-sorbitol, D-mannitol, glycerol, meso-erythritol, and 2,3-butanediol . ARDH may have its primary function in the oxidative fermentation of ketose production by acetic acid bacteria . ARDH contained no heme component, unlike the type II or type III quinoprotein alcohol dehydrogenase (ADH) and did not react with primary alcohols.

Biodegradation, 2001, 12(4), 247 - 57
Protein degradation during anaerobic wastewater treatment: derivation of stoichiometry; Ramsay IR et al.; The stoichiometry of reactions that describe protein degradation in anaerobic treatment systems were investigated . A methodology was developed to describe protein degradation to organic acids using a single reaction step . The reactions for individual amino acid fermentation and their mediating organisms were reviewed . The dominant fermentation pathways were selected based on a number of assumptions . Using the amino acid content of a model protein, it was then possible to determine stoichiometric coefficients for each major organic acid product in the overall degradation of the protein . The theoretical coefficients were then compared to those determined from two experimental runs on a continuously-fed, well-mixed, laboratory-scale anaerobic wastewater treatment system . In general, the coefficients compared well thus validating the use of a single reaction step for the overall catabolic reaction of protein degradation to organic acids . Furthermore, even when the protein concentration in feed or the feed flow rate was doubled, the amino acid fermentation pathways were found to occur predominantly by only one pathway . Although the choice of Stickland reactions over uncoupled degradation provided good comparisons, an electron balance showed that only about 40% of the amino acids could have proceeded coupled to other amino acid reactions . Uncoupled degradation of the remaining amino acids must have relied on the uptake of hydrogen produced from these reactions by hydrogen-consuming methane bacteria.

J Biol Chem, 2002 Apr 19, 277(16), 13983 - 8 Epub 2002 Feb 01.
Elucidation of the metabolic fate of glucose in the filamentous fungus Trichoderma reesei using expressed sequence tag (EST) analysis and cDNA microarrays; Chambergo FS et al.; Despite the intense interest in the metabolic regulation and evolution of the ATP-producing pathways, the long standing question of why most multicellular microorganisms metabolize glucose by respiration rather than fermentation remains unanswered . One such microorganism is the cellulolytic fungus Trichoderma reesei (Hypocrea jecorina) . Using EST analysis and cDNA microarrays, we find that in T . reesei expression of the genes encoding the enzymes of the tricarboxylic acid cycle and the proteins of the electron transport chain is programmed in a way that favors the oxidation of pyruvate via the tricarboxylic acid cycle rather than its reduction to ethanol by fermentation . Moreover, the results indicate that acetaldehyde may be channeled into acetate rather than ethanol, thus preventing the regeneration of NAD(+), a pivotal product required for anaerobic metabolism . The studies also point out that the regulatory machinery controlled by glucose was most probably the target of evolutionary pressure that directed the flow of metabolites into respiratory metabolism rather than fermentation . This finding has significant implications for the development of metabolically engineered cellulolytic microorganisms for fuel production from cellulose biomass.

J Microbiol Immunol Infect, 2001 Dec, 34(4), 235 - 42
Oxytetracycline production by immobilized Streptomyces rimosus; Yang SS et al.; This study examined whether the production of oxytetracycline by Streptomyces rimosus TM-55 (CCRC 960061) would be improved with calcium alginate immobilization in submerged fermentation compared with free cells . Results showed that in 1-mL culture broth, free cells produced 121 to 124 microg of oxytetracycline, whereas immobilized cells produced 153 to 252 microg . Immobilization of the cells retarded the growth rate of S . rimosus but increased the length of the growth period and improved the oxytetracycline production . The specific oxytetracycline productivity was 33.3 to 34.2 mg in each gram of free dry cells and was 40.2 to 40.7 mg in immobilized dry cells . The optimum immobilization conditions were alginate 2% and bead diameter of 2.13 mm . Oxytetracycline production increased with increasing inoculum density but decreased with increasing bead diameter . Ethylenediaminetetraacetic acid or monovalent ions could react with calcium in the bead or replace it with sodium ion, thereby reducing the strength of the beads.

J Nutr, 2002 Feb, 132(2), 238 - 44
Soymilk products affect ethanol absorption and metabolism in rats during acute and chronic ethanol intake; Kano M et al.; In this study we evaluated the effects of soy products on ethanol metabolism during periods of acute and chronic consumption in rats . Gastric ethanol content and blood ethanol and acetaldehyde concentrations were investigated after the oral administration of ethanol (34 mmol/kg) plus soy products such as soymilk (SM) or fermented soymilk (FSM) . The gastric ethanol concentration of the FSM group was greater than that of the control group, whereas portal and aortal blood ethanol concentrations of the FSM group were lower than in controls . The aortal acetaldehyde concentration in the FSM group was lower than that of the control group . The direct effect of isoflavones on liver function was investigated by using hepatocytes isolated from untreated rats . Genistein (5 micromol/L) decreased ethanol (P = 0.045) and tended to decrease acetaldehyde (P = 0.10) concentrations in the culture filtrate . Some variables of ethanol metabolism in the liver were investigated after chronic ethanol exposure for 25 d . Rats consumed a 5% ethanol fluid plus the SM diet, the FSM diet or a control diet . Microsomal ethanol oxidizing activity was significantly lower in the FSM group than the control group . Furthermore, cytosolic glutathione S-transferase activity was higher in the SM and FSM groups than in the control group . Acetaldehyde dehydrogenase activity (low K(m)) in the FSM group (P = 0.15), but not in the SM group (P = 0.31), tended to be greater than in the control group . The amount of thiobarbituric acid reacting substances in the liver of the SM and FSM groups tended to be less than that of the control group (P = 0.18 and 0.10, respectively) . These results demonstrate that soymilk products inhibit ethanol absorption and enhance ethanol metabolism in rats.

Appl Environ Microbiol, 2002 Feb, 68(2), 893 - 900
Characterization and description of Anaeromyxobacter dehalogenans gen . nov., sp . nov., an aryl-halorespiring facultative anaerobic myxobacterium; Sanford RA et al.; Five strains were isolated which form a physiologically and phylogenetically coherent group of chlororespiring microorganisms and represent the first taxon in the Myxobacteria capable of anaerobic growth . The strains were enriched and isolated from various soils and sediments based on their ability to grow using acetate as an electron donor and 2-chlorophenol (2-CPh) as an electron acceptor . They are slender gram-negative rods with a bright red pigmentation that exhibit gliding motility and form spore-like structures . These unique chlororespiring myxobacteria also grow with 2,6-dichlorophenol, 2,5-dichlorophenol, 2-bromophenol, nitrate, fumarate, and oxygen as terminal electron acceptors, with optimal growth occurring at low concentrations (<1 mM) of electron acceptor . 2-CPh is reduced by all strains as an electron acceptor in preference to nitrate, which is reduced to ammonium . Acetate, H(2), succinate, pyruvate, formate, and lactate were used as electron donors . None of the strains grew by fermentation . The 16S ribosomal DNA (rDNA) sequences of the five strains form a coherent cluster deeply branching within the family Myxococcaceae within the class Myxobacteria and are mostly closely associated with the Myxococcus subgroup . With the exception of anaerobic growth and lack of a characteristic fruiting body, these strains closely resemble previously characterized myxobacteria and therefore should be considered part of the Myxococcus subgroup . The anaerobic growth and 9.0% difference in 16S rDNA sequence from those of other myxobacterial genera are sufficient to place these strains in a new genus and species designated Anaeromyxobacter dehalogenans . The type strain is 2CP-1 (ATCC BAA-258).

Biotechnol Prog, 2002 Jan-Feb, 18(1), 51 - 4
Two-stage culture process for improved production of ganoderic acid by liquid fermentation of higher fungus Ganoderma lucidum; Fang QH et al.; Investigations on the impact of pellet size on the cellular oxygen uptake and accumulation of ganoderic acid (GA) suggested the favorable effect of oxygen limitation on GA formation by the higher fungus Ganoderma lucidum . A two-stage fermentation process was thus proposed for enhanced GA production by combining conventional shake-flask fermentation with static culture . A high cell density of 20.9 g of DW/L (DW = dry cell weight) was achieved through a 4-day shake-flask fermentation followed by a 12-day static culture . A change in the cell morphology and a decrease in the sugar consumption rate were observed during the static culture . The GA production in the new two-stage process was considerably enhanced with its content increased from 1.36 (control) to 3.19 mg/100 mg of DW, which was much higher than previously observed.

Biotechnol Prog, 2002 Jan-Feb, 18(1), 29 - 35
Separation characteristics of liquid nematode cultures and the design of recovery operations; Young JM et al.; Production of nematode-based pesticides involves the recovery of a viable nematode life stage known as the infective juvenile (IJ) from fermentation broth . Waste components to be separated from the IJs include non-IJ life stages, dead nematodes, nematode debris, spent media, and the nematode's associated bacteria . This paper reports separation characteristics of liquid cultures and suspensions of the nematodes Phasmarhabditis hermaphrodita, Steinernema feltiae, and Heterorhabditis megidis measured at small scale . Separation characteristics were determined for dead-end filtration, gravity settling and flotation . Results were used to identify large-scale recovery procedures . Separation of culture liquid by dead-end filtration of the crude fermentation broth was not possible due to rapid blinding of filters . However, nematode-water suspensions prepared by gravity settling could be concentrated using this separation method . Settling tests indicated that IJs could be efficiently separated from culture liquid by centrifugation but not by gravity settling . Examination of the effects of nematode concentration indicated an optimum concentration for gravity settling that may entail modest dilution of the fermentation broth . Flocculation of insoluble spent media in suspensions of P . hermaphrodita prevented its separation from nematodes by gravity settling . However, attachment of air bubbles to spent media allowed removal by flotation . Finally, adjustment of continuous phase density using sucrose allowed separation of non-IJ life stages, dead nematodes, and discarded cuticles from the IJs by flotation . The efficiency of this separation decreased with increasing nematode-solute contact time.

Biotechnol Prog, 2002 Jan-Feb, 18(1), 6 - 20
Global gene expression differences associated with changes in glycolytic flux and growth rate in Escherichia coli during the fermentation of glucose and xylose; Gonzalez R et al.; The simplicity of the fermentation process (anaerobic with pH, temperature, and agitation control) in ethanologenic Escherichia coli KO11 and LY01 makes this an attractive system to investigate the utility of gene arrays for biotechnology applications . By using this system, gene expression, glycolytic flux, and growth rate have been compared in glucose-grown and xylose-grown cells . Although the initial metabolic steps differ, ethanol yields from both sugars were essentially identical on a weight basis, and little carbon was diverted to biosynthesis . Expression of only 27 genes changed by more than 2-fold in both strains . These included induction of xylose-specific operons (xylE, xylFGHR, and xylAB) regulated by XylR and the cyclic AMP-CRP system and repression of Mlc-regulated genes encoding glucose uptake (ptsHIcrr, ptsG) and mannose uptake (manXYZ) during growth on xylose . However, expression of genes encoding central carbon metabolism and biosynthesis differed by less than 2-fold . Simple statistical methods were used to investigate these more subtle changes . The reproducibility (coefficient of variation of 12%) of expression measurements (mRNA as cDNA) was found to be similar to that typically observed for in vitro measurements of enzyme activities . Using Student's t test, many smaller but significant sugar-dependent changes were identified (p < 0.05 in both strains) . A total of 276 genes were more highly expressed during growth on xylose; 307 genes were more highly expressed with glucose . Slower growth (lower ATP yield) on xylose was accompanied by decreased expression of 62 genes concerned with the biosynthesis of small molecules (amino acids, nucleotides, cofactors, and lipids), transcription, and translation; 5 such genes were expressed at a higher level . In xylose-grown cells, 90 genes associated with the transport, catabolism, and regulation of pathways for alternative carbon sources were expressed at higher levels than in glucose-grown cells, consistent with a relaxation of control by the cyclic AMP-CRP regulatory system . Changes in expression of genes encoding the Embden-Meyerhof-Parnas (EMP) pathway were in excellent agreement with calculated changes in flux for individual metabolites . Flux through all but one step, pyruvate kinase, was predicted to be higher during glucose fermentation . Expression levels (glucose/xylose) were higher in glucose-grown cells for all EMP genes except the isoenzymes encoding pyruvate kinase (pykA and pykF) . Expression of both isoenzymes was generally higher during xylose fermentation but statistically higher in both strains only for pykF encoding the isoenzyme activated by fructose-6-phosphate, a key metabolite connecting pentose metabolism to the EMP pathway . The coordinated changes in expression of genes encoding the EMP pathway suggest the presence of a common regulatory system and that flux control within the EMP pathway may be broadly distributed . In contrast, expression levels for genes encoding the Pentose-Phosphate pathway did not differ significantly between glucose-grown and xylose-grown cells.

J Chromatogr A, 2002 Jan 4, 942(1-2), 123 - 31
Direct capture of product from fermentation broth using a cell-repelling ion exchanger; Dainiak MB et al.; A new technique for treating anion exchangers has been proposed allowing direct capture of the fermentation product, shikimic acid directly from the cell-containing fermentation broth . A layer of hydrophilic polymer, poly(acrylic acid) (PAA) has been physically adsorbed on the anion exchanger followed by a covalent cross-linking of PAA . The PAA layer is penetrable for small molecules despite being negatively charged as PAA is, but the polymer layer repels large negatively charged structures like cell debris and cells preventing them from adsorption to the chromatographic matrix . The binding capacity for pure shikimic was about 81 mg/ml adsorbent for both cross-linked PAA-Amberlite and native Amberlite in the fluidized mode of column operation . Binding capacity dropped to 17 and 15 mg per ml adsorbent, respectively, when using filtrated fermentation broth and to about 10 mg/ml adsorbent for cross-linked PAA-Amberlite when using directly the fermentation broth containing cells . Native Amberlite cannot be used for the direct capture of shikimic acid due to the immediate clogging of the column and the collapse of the expanded bed . The cross-linked PAA-Amberlite was used repeatedly for the direct adsorption of shikimic acid from the industrial fermentation broth.

J Contam Hydrol, 2001 Dec 15, 53(3-4), 387 - 406
Progression of natural attenuation processes at a crude oil spill site: II . Controls on spatial distribution of microbial populations; Bekins BA et al.; A multidisciplinary study of a crude-oil contaminated aquifer shows that the distribution of microbial physiologic types is strongly controlled by the aquifer properties and crude oil location . The microbial populations of four physiologic types were analyzed together with permeability, pore-water chemistry, nonaqueous oil content, and extractable sediment iron . Microbial data from three vertical profiles through the anaerobic portion of the contaminated aquifer clearly show areas that have progressed from iron-reduction to methanogenesis . These locations contain lower numbers of iron reducers, and increased numbers of fermenters with detectable methanogens . Methanogenic conditions exist both in the area contaminated by nonaqueous oil and also below the oil where high hydrocarbon concentrations correspond to local increases in aquifer permeability . The results indicate that high contaminant flux either from local dissolution or by advective transport plays a key role in determining which areas first become methanogenic . Other factors besides flux that are important include the sediment Fe(II) content and proximity to the water table . In locations near a seasonally oscillating water table, methanogenic conditions exist only below the lowest typical water table elevation . During 20 years since the oil spill occurred, a laterally continuous methanogenic zone has developed along a narrow horizon extending from the source area to 50-60 m downgradient . A companion paper {J . Contam . Hydrol . 53, 369-386} documents how the growth of the methanogenic zone results in expansion of the aquifer volume contaminated with the highest concentrations of benzene, toluene, ethylbenzene, and xylenes.

J Contam Hydrol, 2001 Dec 15, 53(3-4), 233 - 67
Processes controlling the distribution and natural attenuation of dissolved phenolic compounds in a deep sandstone aquifer; Thornton SF et al.; Processes controlling the distribution and natural attenuation (NA) of phenol, cresols and xylenols released from a former coal-tar distillation plant in a deep Triassic sandstone aquifer are evaluated from vertical profiles along the plume centerline at 130 and 350 m from the site . Up to four groups of contaminants (phenols, mineral acids, NaOH, NaCl) form discrete and overlapping plumes in the aquifer . Their distribution reflects changing source history with releases of contaminants from different locations . Organic contaminant distribution in the aquifer is determined more by site source history than degradation . Contaminant degradation at total organic carbon (TOC) concentrations up to 6500 mg l(-1) (7500 mg l(-1) total phenolics) is occurring by aerobic respiration NO3-reduction, Mn(IV)-/Fe(III)-reduction, SO4-reduction, methanogenesis and fermentation, with the accumulation of inorganic carbon, organic metabolites (4-hydroxybenzaldehyde, 4-hydroxybenzoic acid), acetate, Mn(II), Fe(II), S(-II), CH4 and H2 in the plume . Aerobic and NO3-reducing processes are restricted to a 2-m-thick plume fringe but Mn(IV)-/Fe(II)-reduction, SO4-reduction, methanogenesis and fermentation occur concomitantly in the plume . Dissolved H2 concentrations in the plume vary from 0.7 to 110 nM and acetate concentrations reach 200 mg l(-1) . The occurrence of a mixed redox system and concomitant terminal electron accepting processes (TEAPs) could be explained with a partial equilibrium model based on the potential in situ free energy (deltaGr) yield for oxidation of H2 by specific TEAPs . Respiratory processes rather than fermentation are rate limiting in determining the distribution of H2 and TEAPs and H2 dynamics in this system . Most (min . 90%) contaminant degradation has occurred by aerobic and NO3-reducing processes at the plume fringe . This potential is determined by the supply of aqueous O2 and NO3 from uncontaminated groundwater, as controlled by transverse mixing, which is limited in this aquifer by low dispersion . Consumption to date of mineral oxides and SO4 is, respectively, <0.15% and 0.4% of the available aquifer capacity, and degradation using these oxidants is <10% . Fermentation is a significant process in contaminant turnover, accounting for 21% of degradation products present in the plume, and indicating that microbial respiration rates are slow in comparison with fermentation . Under present conditions, the potential for degradation in the plume is very low due to inhibitory effects of the contaminant matrix . Degradation products correspond to <22% mass loss over the life of the plume, providing a first-order plume scale half-life >140 years . The phenolic compounds are biodegradable under the range of redox conditions in the aquifer and the aquifer is not oxidant limited, but the plume is likely to be long-lived and to expand . Degradation is likely to increase only after contaminant concentrations are reduced and aqueous oxidant inputs are increased by dispersion of the plume . The results imply that transport processes may exert a greater control on the natural attenuation of this plume than aquifer oxidant availability.

Ned Tijdschr Tandheelkd, 1992 Jun, 99(6), 201 - 3
{Caries-- changing patterns}; ten Cate JM; This article briefly describes the pathogenesis of dental caries . It focuses on the relevant chemical processes and histological changes in dental enamel . Recent studies have shown that the mineral balance at the tooth-oral fluid interface are determinants for the occurrence of caries, and more important than the intrinsic tissue properties . During periods of low pH, following bacterial metabolism of fermentable carbohydrates, enamel is demineralized . However, loss of tissue may be compensated by mineral deposition from saliva during subsequent periods at neutral pH ('remineralization') . The mineral balance is positively affected by the presence of low fluoride levels in the oral fluids . Clinically this becomes manifest in the decreasing rates of caries initiation and progression . Also it may affect the appearance of incipient enamel lesions, which in turn could complicate caries diagnosis . The changing patterns of dental changes thus have implications for procedures in preventive and restorative practise.

Int J Food Sci Nutr, 2002 Jan, 53(1), 15 - 27
Nutritional and sensory evaluation of tempe-fortified maize-based weaning foods; Egounlety M et al.; Maize-based weaning foods prepared from whole maize meal or dehydrated fermented maize (ogi) flour fortified with soybean, cowpea or groundbean tempe, with or without the addition of melon seed flour were fed to 40 albino weanling rats . The nutrient quality of the weaning foods was monitored by the measurement of protein efficiency ratio (PER), net protein ratio (NPR), true digestibility (TD), biological value (BV) and net protein utilization (NPU) . Amino acid composition and amino acid scores were determined . The weaning foods were also evaluated for sensory properties and acceptability by nursing mothers and their children . Protein efficiency ratio, net protein retention and net protein utilization of the fortified weaning foods were not significantly different (P > 0.05) when compared to casein diet (control) . True digestibility of tempe-fortified maize-based weaning foods averaged 85.4 +/- 3.4% compared to 94.4%, for casein diet . Results from sensory analysis showed that relative to tempe-fortified maize-based weaning foods, most mothers preferred Cerelac, a commercial weaning food, and its porridge because of its vanillic flavour and sweet taste . Despite the low scores recorded for aroma and taste of tempe-fortified maize-based weaning foods, most mothers and their children found porridges prepared from these foods acceptable, with a preference for ogi fortified with cowpea tempe . Tempe-fortified maize-based weaning foods had high protein quality and can support the growth of infants in developing countries especially during the critical weaning period (6-12 months) . They were comparable to Cerelac, a commercial baby food in colour and texture.

World J Gastroenterol, 2001 Dec, 7(6), 741 - 51
Management of patients with a short bowel; Nightingale JM; There are two common types of adult patient with a short bowel, those with jejunum in continuity with a functioning colon and those with a jejunostomy . Both groups have potential problems of undernutrition, but this is a greater problem in those without a colon, as they do not derive energy from anaerobic bacterial fermentation of carbohydrate to short chain fatty acids in the colon . Patients with a jejunostomy have major problems of dehydration, sodium and magnesium depletion all due to a large volume of stomal output . Both types of patient have lost at least 60 cm of terminal ileum and so will become deficient of vitamin B(12) . Both groups have a high prevalence of gallstones (45%) resulting from periods of biliary stasis . Patients with a retained colon have a 25% chance of developing calcium oxalate renal stones and they may have problems with D(-) lactic acidosis . The survival of patients with a short bowel, even if they need long-term parenteral nutrition, is good.

Membr Cell Biol, 2001, 14(6), 749 - 63
Participation of hyf-encoded hydrogenase 4 in molecular hydrogen release coupled with proton-potassium exchange in Escherichia coli; Bagramyan K et al.; In a previous work (Trchounian et al., Biol . Membrany 16:416-428 (1999) (in Russian)) we reported the interrelations between production of H2 and H+-K+ exchange in fermenting Escherichia coli grown under anaerobic conditions at pH 7.5 . The ion fluxes had stable stoichiometry 2H+/K+ and were N,N'-dicyclohexylcarbodiimide (DCC)-inhibitable at different external pH and K+ activity . In the present study, the H2 production was further studied in fermenting bacteria grown at pH 7.5 or 6.5 . The H2 production was inhibited by DCC and did not occur if bacteria were grown at pH 7.5 in a medium containing formate or upon hypoosmotic stress . The H2 production was not sensitive to osmotic stress when bacteria were grown at pH 6.5 . Formation of H2 and 2H+/K+ exchange were not observed in mutants with deletions of the hyfoperon genes, encoding membrane-associated hydrogenase 4 . K+ influx in these mutants was not sensitive to valinomycin, in contrast to the K+ influx in the parental strain . If grown at pH 6.5, the mutants produced H2 and carried out 2H+/K+ exchange, when subjected to the hyperosmotic stress . The results suggest a participation of hydrogenase 4 in the production of H2 and proton-potassium exchange in fermenting E . coli grown at pH 7.5 . In bacteria grown at pH 6.5 or in a medium containing formate, another membrane-bound hydrogenase, namely hydrogenase 3, may be responsible for the H2 production.

Antonie Van Leeuwenhoek, 2001 Sep, 79(3-4), 393 - 9
Influence of killer strains of Saccharomyces cerevisiae on wine fermentation; Perez F et al.; The effect of killer strains of Saccharomyces cerevisiae on the growth of sensitive strains during must fermentation was studied by using a new method to monitor yeast populations . The capability of killer yeast strains to eliminate sensitive strains depends on the initial proportion of killer yeasts, the susceptibility of sensitive strains, and the treatment of the must . In sterile filtered must, an initial proportion of 2-6% of killer yeasts was responsible for protracted fermentation and suppression of isogenic sensitive strains . A more variable initial proportion was needed to get the same effect with non-isogenic strains . The suspended solids that remain in the must after cold-settling decreased killer toxin effect . The addition of bentonite to the must avoided protracted fermentation and the suppression of sensitive strains; however, the addition of yeast dietary nutrients with yeast cell walls did not, although it decreased fermentation lag.

Antonie Van Leeuwenhoek, 2001 Sep, 79(3-4), 345 - 52
Yeast population dynamics in spontaneous fermentations: comparison between two different wine-producing areas over a period of three years; Torija MJ et al.; Yeast ecology, biogeography and biodiversity are important and interesting topics of research . The population dynamics of yeasts in several cellars of two Spanish wine-producing regions was analysed for three consecutive years (1996 to 1998) . No yeast starter cultures had been used in these wineries which therefore provided an ideal winemaking environment to investigate the dynamics of grape-related indigenous yeast populations . Non-Saccharomyces yeast species were identified by RFLPs of their rDNA, while Saccharomyces species and strains were identified by RFLPs of their mtDNA . This study confirmed the findings of other reports that non-Saccharomyces species were limited to the early stages of fermentation whilst Saccharomyces dominated towards the end of the alcoholic fermentation . However, significant differences were found with previous studies, such as the survival of non-Saccharomyces species in stages with high alcohol content and a large variability of Saccharomyces strains (a total of 112, all of them identified as Saccharomyces cerevisiae) with no clear predominance of any strain throughout all the fermentation, probably related to the absence of killer phenotype and lack of previous inoculation with commercial strains.

Adv Biochem Eng Biotechnol, 2001, 73, 53 - 84
Metabolic engineering of Saccharomyces cerevisiae for xylose utilization; Hahn-Hagerdal B et al.; Metabolic engineering of Saccharomyces cerevisiae for ethanolic fermentation of xylose is summarized with emphasis on progress made during the last decade . Advances in xylose transport, initial xylose metabolism, selection of host strains, transformation and classical breeding techniques applied to industrial polyploid strains as well as modeling of xylose metabolism are discussed . The production and composition of the substrates--lignocellulosic hydrolysates--is briefly summarized . In a future outlook iterative strategies involving the techniques of classical breeding, quantitative physiology, proteomics, DNA micro arrays, and genetic engineering are proposed for the development of efficient xylose-fermenting recombinant strains of S . cerevisiae.

Adv Biochem Eng Biotechnol, 2001, 73, 31 - 52
Process development and metabolic engineering for the overproduction of natural and unnatural polyketides; McDaniel R et al.; Polyketide natural products are a rich source of bioactive substances that have found considerable use in human health and agriculture . Their complex structures require that they be produced via fermentation processes . This review describes the strategies and challenges used to develop practical fermentation strains and processes for polyketide production . Classical strain improvement procedures, process development methods, and metabolic engineering approaches are described . The elucidation of molecular mechanisms that underlie polyketide biosynthesis has played an important role in each of these areas over the past few years.

Cancer Epidemiol Biomarkers Prev, 2002 Jan, 11(1), 121 - 6
Dietary determinants of plasma enterolactone; Horner NK et al.; Enterolactone is a lignan produced by fermentation of dietary precursors in the human gut . Because lignan precursors are uniquely found in plant foods, plasma enterolactone concentration may serve as a biological marker of plant food consumption . This cross-sectional study examined associations of dietary intake with plasma enterolactone concentration . Weight-stable, 20-40-year-old volunteers (115 women and 78 men in Seattle, Washington) reporting intake of < or =2.5 or > or =4.5 fruit and vegetable servings/day and no antibiotic use for > or =3 months completed a food frequency questionnaire and 3-day food record . Time-resolved fluoroimmunoassay was used to measure plasma enterolactone . Based on diet records, plasma enterolactone was positively correlated with daily vegetable servings (r = 0.17; P < 0.05), fiber (r = 0.36; P < 0.0001), alcohol (r = 0.24; P < 0.001), caffeine (r = 0.21; P < 0.001), and daily botanical group servings {Chenopodiaceae (r = 0.15; P < 0.05), Juglandaceae (r = 0.15; P < 0.05), Leguminosae (r = 0.20; P < 0.001), Pedaliaceae (r = 0.20; P < 0.001), and Vitaceae (r = 0.20; P < 0.001)} . Fat-related variables were not correlated with plasma enterolactone . Based on linear regression models, plasma enterolactone increased by 37.0% (SE = 2.3%) for each 10-g increase in fiber and by 6.6% (SE = 0.2%) for each 50-mg serving of caffeine . Participants consuming 0.5-1 alcoholic drink/day had plasma enterolactone concentrations that were 131.4% (SE = 37.6%) higher than those of nondrinkers . Although plasma enterolactone may be useful as a biological measure of exposure to lignan-containing foods, it may be of limited use as a specific biomarker of fruit and vegetable or plant food intake because coffee, tea, and alcoholic beverages also significantly increase its plasma concentration.

Trends Biotechnol, 2002 Feb, 20(2), 72 - 8
Field-assisted extraction of cells, particles and macromolecules; Karumanchi RS et al.; Improved bioseparation techniques are increasingly important for biotechnology because separation is often the limiting factor for the success of biological processes . Manufacturers of new enzymes and pharmaceutical products require improved methods for recovering intact cells and intracellular products . Similarly the isolation, purification and concentration of many biomolecules produced in fermentation processes is extremely important . Often such downstream processing contributes a large portion of the product cost and thus efficient and economical alternative approaches to bioseparation processes are needed to eliminate, reduce or facilitate the handling of solids . Field-assisted separations, which hold immense potential for providing a major improvement in bioseparation in the near future, are considered in this review . Special emphasis is given to multistage methods, which are cost-effective compared with competing technologies . Commercial applications of these methods are detailed, we present suggestions for future work and we analyse the scale-up and economic aspects of these processes.

Analyst, 2001 Dec, 126(12), 2149 - 52
Enzymatic reactions for the determination of sugars in food samples using the differential pH technique; Luzzana M et al.; All ATP coupled reactions, when performed at neutral or moderately alkaline pH, produce an acidification of the reaction mixture . The detection of small pH changes--0.1 mpH (1 mpH = 10(-3) pH)--in a constant buffering capacity solution makes it possible to quantify, over a wide concentration range (1-1500 mmol L(-1)), various analytes with very high precision and accuracy . Glucose, fructose, glycerol and gluconic acid can be analysed in less than 1 min with a single step reaction . Wine samples were analysed using the hexokinase reaction for glucose + fructose (sugars undergoing fermentation) and compared against an established method, showing excellent performance over the whole range of concentrations (R = 0.9994) . Increased sensitivity in some applications can be obtained by cycling reactions, e.g . a kinase reaction followed by a phosphatase reaction . in a one step analysis, as required for lactulose assay in milk, a useful indicator of heat treatment damage . A sensitivity well below 0.1 mmol L(-1) in the original milk sample has been demonstrated.

Analyst, 2001 Dec, 126(12), 2128 - 33
Enantioseparation of chiral amino acids as the N(O,S)-ethoxycarbonylated diastereomeric esters by achiral dual-capillary column gas chromatography; Lee J et al.; The enantioseparation of 30 racemic amino acids in a single analysis is described for the determination of their absolute configurations . Two-phase extractive ethoxycarbonyl (EOC) reaction with ethyl chloroformate present in the dichloromethane phase was performed to recover amino acids from alkaline aqueous solutions . The resulting N(O,S)-EOC amino acids extracted into an organic solvent after acidification were reacted with a chiral alcohol such as (S)-(+)-3-methylbutan-2-ol, (S)-(+)-butan-2-ol and (S)-(+)-octan-2-ol for gas chromatographic analysis on achiral dual-capillary DB-5 and DB-17 columns of different polarities . Among the chiral reagents examined, (S)-(+)-3-methylbutan-2-ol provided the best diastereomeric structures in resolving all the racemic amino acids into their enantiomeric pairs with high resolution factors (1.2-8.0) . Moreover, the temperature-programmed retention index (I) values measured on the two columns were characteristic of each enantiomer . Hence simple I matching with the reference values was useful in cross-checking for chemical identification and also chiral discrimination . When the present method was applied to a fermented dairy product (Yakult), D-alanine, D-aspartic acid, D-glutamic acid and D-proline were positively detected along with their respective L-forms in addition to glycine.

J Nutr Sci Vitaminol (Tokyo), 2001 Oct, 47(5), 335 - 9
Nutritional effects of cyclodextrins on liver and serum lipids and cecal organic acids in rats; Kaewprasert S et al.; The effect of dietary cyclodextrins on liver and serum lipids and cecal organic acid production was investigated . Male Wistar rats were fed a basal diet and a diet containing 5% of alpha-, beta-, or gamma-cyclodextrin . The body weight gain in rats fed the alpha-cyclodextrin diet was not significantly different from rats fed the other three kinds of diets . The feeding of dietary alpha-cyclodextrin increased total lipid and phospholipids in the liver . Beta-cyclodextrin significantly lowered serum total cholesterol and phospholipid levels compared with the basal diet et al . A decrease in serum triacylglycerol levels was also observed in beta-cyclodextrin-fed rats . Dietary alpha-cyclodextrin significantly increased the weight of cecal tissues and contents, and an approximate fourfold increase in acetate, propionate, and total organic acids was noted, indicating the fermentibility of beta-cyclodextrin compared with the basal diet . It seems likely that the suppression of serum cholesterol levels by alpha- and beta-cyclodextrins might be due to the increasing acetate and propionate productions in the cecum . cecal organic acid, cyclodextrin, serum cholesterol, rats

J Dairy Sci, 2001 Dec, 84(12), 2760 - 9
Effects of substituting barley grain with corn on ruminal fermentation characteristics, milk yield, and milk composition of Holstein cows; Khorasani GR et al.; The influence of corn or barley, or the equal mixture of both, on digestion characteristics and dairy cow performance was evaluated in metabolic and production experiments . Three rumen-cannulated early-lactation cows were used in a 3 x 3 Latin square design experiment to study the effect on ruminal fermentation characteristics and whole-tract digestion of substituting barley grain with corn . Production responses were determined by the use of 27 early-lactation Holstein cows . Cows in the production study were fed the test diets for 12 wk after a 2-wk covariate period . Results from the metabolic study indicated the effects of grain source on ruminal and total-tract digestion to be minimal . Total ruminal volatile fatty acids and acetate concentrations decreased linearly, butyrate increased linearly, and pH and lactic acid concentration were not affected by increasing levels of corn . Apparent digestibility of DM and organic matter showed a quadratic response with increasing the corn level in the diet, with no dietary effect on neutral detergent fiber, acid detergent fiber, and cellulose digestion . Ruminal fermentation characteristics suggest that substitution of barley grain with corn may alter the site of digestion and the end products of digestion that are absorbed by the animal . Multiparous cows failed to respond to treatment, whereas primiparous animals showed the greater response in milk yield and milk-component yield to diets that contained an equal mixture of corn and barley . These results probably reflect a more optimal synchronization of dietary protein and energy for dairy cows fed the 50:50 barley/corn diet.

J Dairy Sci, 2001 Dec, 84(12), 2751 - 9
Effect of type and level of dietary fat on rumen fermentation and performance of dairy cows fed corn silage-based diets; Onetti SG et al.; The objective of this study was to investigate the effects of tallow and choice white grease (CWG) fed at 0, 2, and 4% of the diet dry matter (DM) on rumen fermentation and performance of dairy cows when corn silage is the sole forage source . Fifteen midlactation Holstein cows were used in a replicated 5 x 5 Latin square design with 21-d periods . Treatments were 0% fat (control), 2% tallow, 2% CWG, 4% tallow, and 4% CWG (DM basis) . The forage:concentrate ratio was 50:50, and diets were formulated to contain 18% crude protein and 32% neutral detergent fiber (DM basis) . Cows were allowed ad libitum consumption of diets fed twice daily as total mixed rations . Cows fed supplemental fat had lower DM intake and produced less milk and milk fat than cows fed the control diet . Feeding 4% fat reduced milk production and milk fat yield relative to feeding 2% fat . Treatments had little effect on the concentration of trans-octadecenoic acids in milk fat . Total trans fatty acids were poorly related to changes in milk fat percentage . Ruminal pH and total volatile fatty acids concentration were not affected by supplemental fat . The acetate:propionate ratio, NH3-N, and numbers of protozoa in the rumen were significantly decreased when fat was added to the diets . Source of dietary fat did not affect rumen parameters . There was no treatment effect on in situ corn silage DM and neutral detergent fiber disappearance . Including fat in corn silage-based diets had negative effects on milk production and rumen fermentation regardless of the source or level of supplemental fat.

J Dairy Sci, 2001 Dec, 84(12), 2721 - 9
Rumen acid production from dairy feeds . 1 . Effects on feed intake and milk production of dairy cows offered grass or corn silages; Dewhurst RJ et al.; Earlier studies developed a new approach to feed evaluation, measuring the net acid load that develops during rumen fermentation . Two concentrates were formulated to be isoenergetic and isonitrogenous, with extremes of rumen acid load . A third treatment comprised a 50:50 mixture of these concentrates . These concentrates were evaluated along with ryegrass silage and corn silage . The feeds were evaluated in a continuous culture system adapted to deliver and record the quantities of acid or alkali needed to maintain a constant pH (6.2 to 6.3) . This study confirmed the anticipated ranking of concentrates for rumen acid load, as well as the highly acidogenic nature of corn silage . The concentrates were formulated to balance corn silage and were offered to early-lactation Holstein-Friesian cows at 50% of dry matter intake, with either ryegrass silage or corn silage . Feed intake was lower for animals offered corn silage-based diets (17.4 vs . 22.2 kg of dry matter/d) . Increasing concentrate acid load led to a large decline in dry matter intake for corn silage, although not for grass silage . Feed intake effects were reflected in significant effects on yield of milk (31.0, 29.9, and 26.9 kg/d for low-, medium-, and high-acid load concentrates, respectively) and milk solids . Milk protein concentration was unaffected by concentrate type with corn silage diets but tended to be higher when high acid load concentrates were fed with grass silage . This may reflect the effect of the high starch concentrate rectifying a shortage of glucogenic precursors or microbial protein with the grass silage-based diet.

Toxicol Sci, 2002 Feb, 65(2), 288 - 98
Spinosad insecticide: subchronic and chronic toxicity and lack of carcinogenicity in Fischer 344 rats; Yano BL et al.; Spinosad is an insecticide derived from a naturally occurring bacterium via fermentation . The toxicity of spinosad was characterized in subchronic and chronic toxicity/oncogenicity studies conducted according to standard toxicology regulatory guidelines . Subchronic toxicity was evaluated in groups of 10 Fischer 344 rats/sex given feed containing 0, 0.05, 0.1, 0.2, or 0.4% spinosad (Study 1) or 0, 0.003, 0.006, 0.012, or 0.06% spinosad (Study 2) for 13 weeks . Lower body weights and increased mortality occurred in rats given 0.4% spinosad . Microscopic effects were observed in the adrenal glands, liver, lymphoid cells, reproductive tissues, kidney, thyroid, stomach, lung, and skeletal muscle of rats given > or = 0.05% spinosad, and consisted primarily of vacuolation of cells; however, degenerative, regenerative, and/or inflammatory changes were also noted in some tissues . Vacuolation within a number of tissues was ultrastructurally characterized by an increase in size and number of lysosomes that contained extensive membranous whorls consistent with phospholipidosis . The no observed effect level (NOEL) in the 13-week studies was 0.012% (24 mg/kg/day) spinosad . Chronic toxicity and oncogenicity were evaluated in groups of 60 Fischer 344 rats/sex given feed containing 0, 0.005, 0.02, 0.05, or 0.1% spinosad for up to 2 years . Rats given 0.1% spinosad for 1 year had microscopic effects similar to those observed in the subchronic studies . Vacuolation and inflammation of the thyroid gland also occurred in rats given 0.05% spinosad for 1 year . Excessive mortality occurred in rats from the oncogenicity study given 0.1% spinosad by 21 months, and surviving rats were euthanized because the maximum tolerated dose had been exceeded . Rats given 0.05% spinosad for 2 years had vacuolation and/or inflammation involving the thyroid, lymphoid tissue, and lung . Rats given 0.05% spinosad had similar numbers of neoplasms as control rats, indicating that spinosad was not carcinogenic at dose levels up to 0.05% . The NOEL at 2 years was 0.005% (2.4 mg/kg/day) spinosad.

Toxicol Sci, 2002 Feb, 65(2), 276 - 87
Spinosad insecticide: subchronic and chronic toxicity and lack of carcinogenicity in CD-1 mice; Stebbins KE et al.; The potential toxicologic and oncogenic effects of spinosad, a natural fermentation product with insecticidal properties, were investigated . The 13-week toxicity study consisted of groups of 10 CD-1 mice/sex provided diets containing 0, 0.005, 0.015, 0.045, or 0.12% spinosad (Study 1) . The 0.12% group was terminated on Test Day 44 due to mortality and overt clinical signs of toxicity . An 18-month chronic oncogenicity study consisted of groups of 50 CD-1 mice/sex provided diets containing 0, 0.0025, 0.008, or 0.036% spinosad (Study 2) . Two interim groups of 10 mice/sex/group were terminated after 3 and 12 months . Females given 0.036% were terminated on Day 455 due to markedly lower body weights and feed consumption, as well as excessive mortality . Because of the early termination of the female high-dose group, additional groups of 10 male and female mice (12-month interim necrospy) and 50 male and female mice (18-month necropsy) were provided diets containing 0, 0.0008, or 0.024% spinosad (Study 3) to fully assess potential chronic toxicity and oncogenicity . Standard toxicologic parameters were evaluated consistent with existing regulatory guidelines . The primary effect in the 13-week and 18-month studies was intracellular vacuolation of histiocytic and epithelial cells in numerous tissues and organs at doses of > or = 0.015% . The histological vacuolation corresponded to ultrastructural lysosomal lamellar inclusion bodies . This alteration was consistent with phospholipidosis, a condition that results from accumulation of polar lipids in lysosomes . Lesions with no apparent direct relation to vacuolation were hyperplasia of the glandular mucosa of the stomach, skeletal muscle myopathy, bone marrow necrosis, and anemia with associated splenic hematopoiesis . The incidence of tumors in mice given spinosad was not increased relative to controls at any dose level . The no observed effect level for the 13-week study was 0.005% (6 mg/kg/day) spinosad, and for the chronic toxicity/oncogenicity study was 0.008% (11 mg/kg/day) spinosad for male and female CD-1 mice.

Food Addit Contam, 2002 Jan, 19(1), 55 - 61
Mycotoxins in South African traditionally brewed beers; Odhav B et al.; Traditionally brewed alcoholic beverages are regularly consumed by most ethnic black South Africans . Maize and barley, both of which are used for producing locally brewed alcoholic beer, are frequently contaminated by mycotoxin-producing moulds . The study was undertaken to investigate whether these toxins are present in raw grains and the traditional beers imbibed by the local black African population . It was established that the raw ingredients (sorghum, sorghum malt grains, maize grits), commercially produced traditional beers (Utshwala and Utshwala special) and home-brewed beers (Umqombotha, Isiqatha, Imfulamfula) were contaminated by bacteria and fungi (both yeasts and moulds) . The contaminating moulds were isolated and identified . The contaminated samples were analysed for aflatoxins B1, B2, G1 and G2, zearalenone, citrinin, deoxynivalenol, and ochratoxin A using a multi-mycotoxin thin-layer chromatography screening method and the toxins were quantified by high-performance liquid chromatography . Grain samples were infected by . Aspergillus flavus, A . alliaceus, A . clavatus, Penicillium spp., Rhizopus spp . and Mucor spp . Sorghum malt grain samples contained the toxin zear alenone . No mycotoxin-producing fungi were present in the fermented beers but two of six commercial beer samples contained aflatoxins (200 and 400 microg l(-1) and 45% (13 of 29) of the home-brewed beers had zear alenone (range 2.6-426 microg l(-1) and/or ochratoxin A (3-2340 microg l(-1).

J Anim Sci, 2001 Dec, 79(12), 2949 - 56
In vitro study of the biochemical origin and production limits of odorous compounds in cattle feedlots; Miller DN et al.; Livestock odors are closely correlated to airborne concentrations of volatile organic compounds (VOC), which are a complex mixture of carbon-, sulfur-, and nitrogen-containing compounds produced primarily during the incomplete anaerobic fermentation of animal manure by microorganisms . Volatile fatty acids, alcohols, and aromatic ring compounds comprise a substantial fraction of VOC, yet very little is known about their biochemical origin and environmental factors controlling their production . The anaerobic production of fermentation products and consumption of substrates (CP, starch, and nonstarch carbohydrate) were analyzed in slurries of fresh (< 24 h) and aged (> 1 d) cattle manure over several weeks . Ethanol, acetate, propionate, butyrate, lactate, and H2 were the major products of fermentation . Aged cattle manure produced twice the concentration of VFA during incubation produced by the fresh manure (P < 0.001) . Aromatic compounds (phenols, indoles, and benzoates) remained unchanged in both manures . Production of VFA from fresh manure was inhibited when the pH fell below 4.5 . It is likely that the presence of calcareous soil, which has a high buffering capacity, and lactate-consuming microorganisms minimized acidification in the aged manure slurries . Low starch content limited VFA production in the aged manure . Starch was the likely biochemical source for fermentation products in both manures based on the strong negative correlations between fermentation product and starch content (r = -0.944 and -0.773) and ratio of fermentation products produced to starch consumed (r = 0.64 and 0.72) for fresh and aged manure, respectively . Nonstarch carbohydrate served an indeterminate role in the production of fermentation products . Nonstarch carbohydrate decreased by 4.7 and 23.4 g/L in the fresh and aged manure, respectively, whereas the starch content decreased by 18.6 and 22.4 g/L in the fresh and aged manure, respectively . The concentration of CP did not change, which suggests a balance between protein consumption and new bacterial biomass production . We conclude that the types of substrates in cattle manure and the feedlot soils where they are deposited are significant factors in the production of odors.

Mol Genet Genomics, 2002 Jan, 266(5), 838 - 47 Epub 2001 Nov 07.
Co-ordinate regulation of lactate metabolism genes in yeast: the role of the lactate permease gene JEN1; Lodi T et al.; In the yeast Saccharomyces cerevisiae, the first step in lactate metabolism is its transport across the plasma membrane, a proton symport process mediated by the product of the gene JEN1 . Under aerobic conditions, the expression of JEN1 is regulated by the carbon source: the gene is repressed by glucose and induced by non-fermentable substrates . JEN1 expression is also controlled by oxygen availability, but is unaffected by the absence of haem biosynthesis . JEN1 is negatively regulated by the repressors Mig1p and Mig2p, and requires Cat8p for full derepression . In this report we demonstrate that, in addition to these regulators, the Hap2/3/4/5 complex interacts specifically with a CAAT-box element in the JEN1 promoter, and acts to derepress JEN1 expression . We also provide evidence for transcriptional stimulation of JEN1 by the protein kinase Snf1p . Data are presented which provide a better understanding of the molecular mechanisms implicated in the co-regulation of genes involved in the metabolism of lactate.

J Food Prot, 2002 Jan, 65(1), 12 - 7
A conductance method for the identification of Escherichia coli O157:H7 using bacteriophage AR1; Chang TC et al.; The feasibility of using a specific phage (AR1) in conjunction with a conductance method for the identification of Escherichia coli O157:H7 was evaluated . The multiplication of strains of E . coli O157:H7 was inhibited by AR1; therefore, a time point (detection time, DT) at which an accelerating change in conductance in the culture broth was not obtained . Bacterial strains were subcultured on sorbitol-MacConkey agar and incubated at 35 degrees C for 24 h, and the ability of the bacteria to ferment sorbitol was recorded . An aliquot of 0.5 ml of the bacterial suspension (10(7) CFU/ml) and 0.5 ml of the phage suspension (10(8) PFU/ml) were added to the conductance tube of a Malthus analyzer containing 5 ml of culture broth . The tubes were incubated at 35 degrees C, and conductance changes in the tubes were continuously monitored at 6-min intervals for 24 h by the instrument . A positive reaction was defined as an E . coli strain that could not utilize sorbitol and caused no conductance change (i.e., no DT) within an incubation period of 24 h . Of the 41 strains of E . coli O157:H7 tested, all produced positive reactions . When a total of 155 strains of non-O157:H7 E . coli were tested, 14 did not have a DT within 24 h . However, among these 14 strains, 13 were sorbitol fermenters, and the remaining one was a nonfermenter . Therefore, by definition, only one strain produced a false-positive reaction . The sensitivity and specificity of the present method were 100% (41 of 41) and 99.4% (154 of 155), respectively . The present method incorporating conductimetric measurement and phage AR1 for the identification of E . coli O157:H7 was simple and capable of automation.

Int J Cancer, 2002 Feb 10, 97(5), 567 - 73
Modulation of HMG-N2 binding to chromatin by butyrate-induced acetylation in human colon adenocarcinoma cells; Luhrs H et al.; Butyrate, a short chain fatty acid (SCFA), is generated by anaerobic fermentation of undigested carbohydrates within the colon . Butyrate enhances acetylation of core histones, a process directly linked to the formation of active chromatin and gene expression . However, additional chromatin components also contribute to the formation of transcriptionally active chromatin . The high mobility group protein N2 (HMG-N2), a nonhistone protein, is involved in chromatin structure modulation . We examined the effects of butyrate on HMG-N2 expression, hyperacetylation and chromatin binding . HT29 human adenocarcinoma cells were incubated with butyrate . Levels of HMG-N2 mRNA and of total or acetylated HMG-N2 protein were analyzed . Protein dynamics were investigated with transfected cells expressing HMG-N2-EGFP fusion proteins . Treatment of HT29 cells with butyrate led to significant hyperacetylation of HMG-N2 . Levels of HMG-N2 protein remained unchanged . Northern blot analysis revealed a significant reduction in HMG-N2 mRNA levels after treatment with butyrate . Analysis of HMG-N2-EGFP transfected HT29 cells demonstrated that butyrate treatment changes the binding properties of HMG-N2-EGFP to chromatin . In addition, butyrate treatment resulted in solubilization of endogenous acetylated HMG-N2 into the supernatant of permeabilized cells . We demonstrate that butyrate treatment is associated with hyperacetylation of HMG-N2 protein in HT29 cells . The modulation of this nonhistone chromatin protein resulted in altered binding properties to chromatin . This may represent an additional step in changing chromatin structure and composition with subsequent consequences for transcription and gene expression . Modulation of nonhistone chromatin proteins, like the ubiquitous HMG-N2 proteins, may be partly responsible for the wide range of butyrate-associated effects .

Biotechnol Bioeng, 2002 Mar 20, 77(6), 632 - 40
Monitoring the aroma production during wine-must fermentation with an electronic nose; Pinheiro C et al.; This work discusses the feasibility of using the electronic nose for the on-line and real-time monitoring of the production of a complex aroma profile during a bioconversion process . As a case study, the formation of the muscatel aroma during the wine-must fermentation was selected . During wine-must fermentation, aroma compounds responsible for the organoleptic character are produced in the ppm range, while simultaneously one of the main metabolic products, ethanol, is produced in much higher quantities (up to 10% wt) . Because the sensors of the electronic nose array are cross-selective to different volatile compounds, it was investigated in detail how far the electronic nose was able to evaluate the aroma profile along the fermentation . This article discusses and evaluates subsequently the integration of a membrane separation process-organophilic pervaporation-for selectively enriching aroma compounds relative to ethanol, to improve sample discrimination .

Biotechnol Bioeng, 2002 Mar 20, 77(6), 601 - 13
Estimation of hyphal tensile strength in production-scale Aspergillus oryzae fungal fermentations; Li ZJ et al.; Fragmentation of filamentous fungal hyphae depends on two phenomena: hydrodynamic stresses, which lead to hyphal breakage, and hyphal tensile strength, which resists breakage . The goal of this study was to use turbulent hydrodynamic theory to develop a correlation that allows experimental data of morphology and hydrodynamics to be used to estimate relative (pseudo) tensile strength (sigma(pseudo)) of filamentous fungi . Fed-batch fermentations were conducted with a recombinant strain of Aspergillus oryzae in 80 m(3) fermentors, and measurements were made of both morphological (equivalent hyphal length, L) and hydrodynamic variables (specific power input, epsilon; kinematic viscosity, v) . We found that v increased over 100-fold during these fermentations and, hence, Kolmogorov microscale (lambda) also changed significantly with time . In the impeller discharge zone, where hyphal fragmentation is thought to actually take place, lambda was calculated to be 700-3500 microm, which is large compared to the size of typical fungal hyphae (100-300 microm) . This result implies that eddies in the viscous subrange are responsible for fragmentation . Applying turbulent theory for this subrange, it was possible to calculate sigma(pseudo)from morphological and hydrodynamic measurements . Pseudo tensile strength was not constant but increased to a maximum during the first half and then decreased during the second half of each fermentation, presumably due to differences in physiological state . When a literature correlation for hyphal fragmentation rate (k(frag)) was modified by adding a term to account for viscosity and tensile strength, the result was better qualitative agreement with morphological data . Taken together, these results imply hyphal tensile strength can change significantly over the course of large-scale, fed-batch fungal fermentations and that existing fragmentation and morphology models may be improved if they accounted for variations in hyphal tensile strength with time .

Nature, 2002 Jan 24, 415(6870), 454 - 6
Anaerobic microbial metabolism can proceed close to thermodynamic limits; Jackson BE et al.; Many fermentative bacteria obtain energy for growth by reactions in which the change in free energy (DeltaG') is less than that needed to synthesize ATP . These bacteria couple substrate metabolism directly to ATP synthesis, however, by classical phosphoryl transfer reactions . An explanation for the energy economy of these organisms is that biological systems conserve energy in discrete amounts, with a minimum, biochemically convertible energy value of about -20 kJ mol-1 (refs 1, 2, 3) . This concept predicts that anaerobic substrate decay ceases before the minimum free energy value is reached, and several studies support this prediction . Here we show that metabolism by syntrophic associations, in which the degradation of a substrate by one species is thermodynamically possible only through removal of the end product by another species, can occur at values close to thermodynamic equilibrium (DeltaG' approximately 0 kJ mol-1) . The free energy remaining when substrate metabolism halts is not constant; it depends on the terminal electron-accepting reaction and the amount of energy required for substrate activation . Syntrophic associations metabolize near thermodynamic equilibrium, indicating that bacteria operate extremely efficient catabolic systems.

Health Care Anal, 2001, 9(3), 299 - 319
Historical and philosophical reflections on patient autonomy; Tauber AI; Contemporary American medical ethics was born during a period of social ferment, a key theme of which was the espousal of individual rights . Driven by complex cultural forces united in the effort to protect individuality and self-determined choices, an extrapolation from case law to rights of patients was accomplished under the philosophical auspices of 'autonomy.' Autonomy has a complex history; arising in the modern period as the idea of self-governance, it received its most ambitious philosophical elaboration in Kant's moral philosophy . In examining the Kantian construction, it is evident that neither his universal moral imperative nor his rigorous application of self-legislated ethical action can sustain our own notions of moral agency in a pragmatic, pluralistic society . But the Kantian position is useful in highlighting that self-governance is not equivalent to 'autonomy,' and this distinction defines the limits of autonomy in the clinical setting . A critique of Engelhardt's idea of 'principle of permission' is used to illustrate autonomy's eclipse as a governing principle for medical ethics.

J Agric Food Chem, 2002 Jan 30, 50(3), 648 - 52
Time course study of substrate utilization by Aspergillus flavus in medium simulating corn (Zea mays) kernels; Mellon JE et al.; Utilization of the three major corn reserve materials, starch, triglycerides (refined corn oil), and zein (storage protein), by Aspergillus flavus was monitored in vitro over a 7-day fermentation . Medium composition in which proportions of reserve materials initially approximated proportions in mature corn kernels changed little over the first 18 h . Subsequently, hydrolysis of both starch and triglycerides occurred simultaneously, with peak concentrations of glucose and free fatty acids on day 2 of the fermentation period . Fatty acid concentrations dropped relatively rapidly after day 2 but increased again after day 6 . Aflatoxin B(1) production increased after 36 h, with a peak at day 4 . Aflatoxin B(1) production paralleled fungal biomass production during the exponential growth phase . A . flavus did not appear to preferentially utilize any of the released fatty acids . A number of fungus-specific metabolites were detected, including arabitol, erythritol, mannitol, trehalose, and kojic acid . Mannitol exceeded the other metabolites in concentration, and the timing of mannitol production closely paralleled that of aflatoxin B(1) . Kojic acid concentrations peaked at day 6 . In contrast to previously described selective use of simple carbohydrates by A . flavus, less discrimination was displayed when faced with utilization of complex substrates such as starch or triglycerides.

J Agric Food Chem, 2002 Jan 30, 50(3), 565 - 70
Total phenol, catechin, and caffeine contents of teas commonly consumed in the United kingdom; Khokhar S et al.; Levels of total phenol, catechins, and caffeine in teas commonly consumed in the United Kingdom have been determined using reversed phase high-performance liquid chromatography . Tea bags or tea leaves were purchased from local supermarkets and extracted in boiling water for 5 min . The resulting data showed considerable variability in both total phenols {80.5-134.9 mg/g of dry matter (DM) in black teas and 87-106.2 mg/g of DM in green teas} and catechins (5.6-47.5, 51.5-84.3, and 8.5-13.9 mg/g of DM in black, green, and fruit teas, respectively); this was most probably a result of differing agronomic conditions, leaf age, and storage during and after transport, as well as the degree of fermentation . Caffeine contents of black teas (22-28 mg/g of DM) were significantly higher than in less fermented green teas (11-20 mg/g of DM) . The relative concentration of the five major tea catechins ranked EGCG > ECG > EC > EGC > C . The estimated U.K . dietary intakes of total tea catechins, calculated on the basis of an average tea consumption of three cups of tea (200 mL cup, 1% tea leaves w/v), were 61.5, 92.7, and 405.5 mg/day from fruit teas, black teas, and green teas, respectively . The coefficients of variation were 19.4, 88.6, and 17.3%, respectively, indicating the wide variation in these intakes . The calculated caffeine intake ranged between 92 and 146 mg/day . In addition, many individuals will consume much larger quantities of tea, of various strengths (as determined by the brewing conditions employed) . This broad spread of U.K . daily intakes further emphasizes the need for additional research to relate intake and effect in various population groups.

J Agric Food Chem, 2002 Jan 30, 50(3), 549 - 54
Aroma-active components in fermented bamboo shoots; Fu SG et al.; Bamboo shoots (Phyllostachys pubescens) were fermented and prepared in a traditional Taiwanese manner . Static and dynamic headspace extractions of volatile compounds were conducted by solid phase microextraction (SPME) and by cryogenic focusing purge and trap, respectively . Volatile analysis was conducted with gas chromatography and mass spectrometry . Gas chromatography-olfactometry (GCO) was conducted utilizing the Osme time-intensity method . Of 70 volatile compounds detected, 29 possessed aroma activity, and the most odor active included p-cresol (barn-like), 2-heptanol (mushroom), acetic acid (vinegar), and 1-octen-3-ol (mushroom) . SPME extracted 66 compounds, purge and trap extracted 14 compounds, and 12 compounds were common to both methods . The Osme GCO technique coupled with SPME is an effective tool for the extraction and evaluation of aroma-active headspace volatiles.

Biochim Biophys Acta, 2002 Jan 17, 1553(1-2), 39 - 56
C4-dicarboxylate carriers and sensors in bacteria; Janausch IG et al.; Bacteria contain secondary carriers for the uptake, exchange or efflux of C4-dicarboxylates . In aerobic bacteria, dicarboxylate transport (Dct)A carriers catalyze uptake of C4-dicarboxylates in a H(+)- or Na(+)-C4-dicarboxylate symport . Carriers of the dicarboxylate uptake (Dcu)AB family are used for electroneutral fumarate:succinate antiport which is required in anaerobic fumarate respiration . The DcuC carriers apparently function in succinate efflux during fermentation . The tripartite ATP-independent periplasmic (TRAP) transporter carriers are secondary uptake carriers requiring a periplasmic solute binding protein . For heterologous exchange of C4-dicarboxylates with other carboxylic acids (such as citrate:succinate by CitT) further types of carriers are used . The different families of C4-dicarboxylate carriers, the biochemistry of the transport reactions, and their metabolic functions are described . Many bacteria contain membraneous C4-dicarboxylate sensors which control the synthesis of enzymes for C4-dicarboxylate metabolism . The C4-dicarboxylate sensors DcuS, DctB, and DctS are histidine protein kinases and belong to different families of two-component systems . They contain periplasmic domains presumably involved in C4-dicarboxylate sensing . In DcuS the periplasmic domain seems to be essential for direct interaction with the C4-dicarboxylates . In signal perception by DctB, interaction of the C4-dicarboxylates with DctB and the DctA carrier plays an important role.

Biochem J, 2002 Feb 1, 361(Pt 3), 597 - 604
Phosphorylation of a novel zinc-finger-like protein, ZPR9, by murine protein serine/threonine kinase 38 (MPK38); Seong HA et al.; We have identified previously a new murine protein serine/threonine kinase, MPK38, closely related to the sucrose-non-fermenting protein kinase family {Gil, Yang, Lee, Choi and Ha (1997) Gene 195, 295-301} . Using the C-terminal half of the putative human counterpart of MPK38, HPK38, as a bait in a yeast two-hybrid screen of a human HeLa cDNA library, it was discovered that the zinc-finger-motif-containing protein, termed zinc-finger-like protein 9 (ZPR9), bound both HPK38 and MPK38 . In a co-expression assay, ZPR9 associated with MPK38 in vivo, and we showed that the ZPR9 is also phosphorylated by MPK38 . In addition, ZPR9 physically interacts with itself in mammalian cells . The ZPR9 cDNA hybridized with a mRNA species of approx . 1.7 kb in Northern-blot analysis . The ZPR9 transcript was detected in all tissues examined, including lung, kidney, spleen,liver and brain . Co-expression of ZPR9 with MPK38 caused the accumulation of ZPR9 in the nucleus . These findings suggest a potentially important role for ZPR9 in MPK38-mediated signal transduction, and that ZPR9 is a physiological substrate of MPK38 in vivo.

Bioresour Technol, 2002 Feb, 81(3), 261 - 3
Solid-state production of biopulp by Phanerochaete chrysosporium using steam-exploded wheat straw as substrate; Chen H et al.; A novel material for biopulp-making, steam-exploded wheat straw (SEWS), was studied . During the steam explosion process, the hemicellulose was partly degraded and became water-soluble sugar as the carbon resource of the chosen microbe growth, and compared with non-SEWS, the degradation amount of cellulose decreased and the degradation amount of lignin increased for the fermented steam-exploded wheat straw (FSEWS) cultured with Phanerochaete chrysosporium ME-446 . Under the optimum conditions of solid-state ferrmentation (SSF), the degradation amount of lignin reached 60% on the 5th day and the fermented straw residue could be used directly as the material for pulp making.

J Exp Biol, 1979 Oct, 82, 303 - 20
Metabolic sources of heat and power in tuna muscles . II . Enzyme and metabolite profiles; Guppy M et al.; Tuna appear able to maintain their muscles at 5-10 degrees C above ambient by balancing heat produced in situ and conserved by a counter-current heat exchanger with heat lost to the sea . Metabolite profiles under three different activity states (rest, burst swimming, and steady state swimming during feeding frenzies at sea) were used to identify which metabolic processes in white and red muscles could account for observed excess temperatures . During burst swimming, transient changes in metabolite levels indicate that the metabolism of both red and white muscle contributes to powering burst swimming; red muscle work is sustained mainly by oxidative metabolism while white muscle work depends upon an intense anaerobic glycolysis . The rate of metabolism in red muscle is easily high enough to account for the measured (10 degrees C) increase in temperature at this time . However, in white muscle, anaerobic glycolysis can account for only about a 2 degrees C maximum rise in temperature . The highest sustained swimming speeds and the highest muscle temperatures in skipjack are found during feeding frenzies at sea . As in burst swimming, during steady-state swimming red muscle temperatures can be accounted for by oxidative metabolism . In the case of white muscle, the lactate measurements indicate that anaerobic glycolysis could only lead to a 0.3 degree C temperature rise . However, if the fraction of utilized glycogen that is not fermented (about 60%) is assumed to be fully oxidized, enough heat is generated to raise white muscle temperatures by over 10 degrees C . The observed excess temperature at this time is about 8-10 degrees C, showing that anarerobic carbohydrate metabolism in white muscle is probably the major heat source during feeding frenzies . These interpretations are fully consistent with enzyme profiles of red and white muscles in tuna . They do not, however, explain why tuna have warm muscles . The latter problem is briefly discussed.

Sheng Wu Gong Cheng Xue Bao, 2001 Sep, 17(5), 594 - 7
{The effects of different glucose feeding modes on hEGF production in an excretory recombinant Escherichia coli K12 system}; Xu ZN et al.; The effects of different glucose feeding modes on hEGF expression were evaluated in an excretory recombinant E . coli K12 system . The results showed that, compared with batch cultivation, the plasmid stability and density of plasmid-retaining cells were improved by all three glucose feeding modes (intermittent, pH-stat and constant-rate) . It was shown that hEGF yields were improved up to 25.5% and 28.1% by intermittent or pH-stat glucose feeding respectively . Especially, up to 150% improvement of hEGF production was achieved by constant feeding of 200 g/L glucose solution at a rate of 0.11 mL/min . The effects of further combined feeding with other medium components (ampicillin, nitrogen sources, and inorganic salts) and inducer on hEGF yield were also examined in the bench-top fermentor.

Sheng Wu Gong Cheng Xue Bao, 2001 Sep, 17(5), 584 - 6
{Purification of vancomycin by using magnetic affinity technique}; Guo LA et al.; A new kind of magnetic affinity microspheres (MAMS), whose ligand is D-Ala-D-Ala, was prepared using agarose as matrix . By using this new MAMS vancomycin was purified directly from crude fermentation liquor with only one step . The purity and the mass recovery of vancomycin measured by reverse-phase HPLC were 97% and 87%, respectively . The characteristic of this method was simpler, faster, cheaper and more effective than that of currently used ones.

Sheng Wu Gong Cheng Xue Bao, 2001 Sep, 17(5), 579 - 83
{Factors of laccase producing and fermentation conditions by a new white-rot fungus AH28-2}; Xiao YZ et al.; White-rot fungus AH28-2, a newly isolated strain, produced effectively laccase by induction when grown on a synthetic medium . Aromatic compounds of low molecular weight had an inducing influence on laccase production and its isoenzyme compositions . The using of o-toluidine or syringic acid had the best inducing effect . Cu2+ concentration in medium had distinguished effect on laccase production . Enzyme activity was notably increased by Cu2+ and reached the maximum when Cu2+ final concentration was 5 mumol/L . Mn2+ inhibited the synthesis of laccase . Carbon and nitrogen limitation were not beneficial to laccase synthesis, while high nutrient organic medium was beneficial to the growth of cell and the synthesis of laccase . Using cellobiose as the sole carbon source, the highest level enzyme activity reached 82,923 . 7 u/L under the condition of optimum fermentation with ABTS as substrate . This enzyme activity was 2.9-fold higher compared to the reported data on international references in recent years.

Sheng Wu Gong Cheng Xue Bao, 2001 Sep, 17(5), 575 - 8
{Studies on lignocellulolytic enzymes production and biomass degradation of Pleurotus sp2 and Trametes gallica in wheat straw cultures}; Xie J et al.; Pleurotus sp2 and Trametes gallica were selected in this assay because of their high activities of lignocellulolytic enzymes and the enzyme peaks appeared at the early stage of liquid state fermentation . Solid state fermentation was also investigated for their abilities and behaviors of enzyme-production . The capabilities and characteristics of the two strains in degrading biomass were studied . When Pleurotus sp2 was incubated in wheat straw powder containing the liquid medium of low-nitrogen, no-carbon and high inorganic salt, the activities of MnP and Lac reached the peaks on the tenth day, but the activities of hemicellulases reached the peak on the 40th day . Pleurotus sp2 caused 17.6% of biomass loss . When T . gallica was incubated in wheat straw powder containing the liquid medium of hlig-nitrogen, or low-nitrogen, no-carbon and high inorganic salt, the activities of MnP reached the peaks on the tenth day, the lac and hemicelluloses on the 40th day, and the lignin peroxidases reached the peaks on the 50th day, and it caused more than 64% of biomass loss . Among them the hemicellulose was degraded by 71.96%, and the cellulose 66.21% . T . gallica was very capable of degrading lignin of wheat straw and caused 34.37% loss during 20 days, 46 . 71% loss during 30 days and 70.14% loss during 60 days . It was interesting that T . gallica degraded lignin preferentially with respect to cellulose, which was very beneficial to biopulping of paper industry.

Sheng Wu Gong Cheng Xue Bao, 2001 Sep, 17(5), 570 - 4
{The bottleneck steps limiting maturation of penicillin G acylase in Escherichia coli}; Xu JN et al.; We have identified the bottleneck steps limiting maturation of penicillin G acylase (PAC) through comparison of the maturation performance for various PAC-expression systems (Pac, Tac, T7, Vgb + T7) with different efficiencies of proteolysis, subunit folding and assembly . The maturation of PAC could be limited by various steps, such as translocation, periplasmic proteolysis, subunit folding and assembly depending on the host/vector systems . In BL21(pPA6) cells, maturation of PAC were limited by proteolysis and folding steps; the efficiency of proteolysis was 57.2%; the subunit folding and assembly capacity was 0.72 . In BL21(pKKpacSP) cells, the stability and folding of alpha subunit was bottleneck steps . In T7 and dissolved-oxygen regulation expression systems, PAC proprecursor could be maturated efficiently . Results also indicate that the folding of alpha peptide plays a key role in folding of precursor for PAC in E . coli . Developing proper host/vector systems and fermentation technology with superior abilities on subunit folding and assembly of precursor for PAC could be plausible for enhancing production of PAC . In this study, pac could be expressed (transcribed, translated and maturated) efficiently under the control of T7 promoter.

Sheng Wu Gong Cheng Xue Bao, 2001 Sep, 17(5), 557 - 60
{The RAPD analysis of haploid strain of thermotolearnt yeast}; Zhu XF et al.; The haploid strains HZ line from the thermololeant strain HU-TY-1 of Saccharomyces cerevisiae have been obtained by sporulation, and the analysis of growth and fermentation test was performed . The strains HZ-21 and HZ-84 were used as the analysis of random amplified polymerphic DNA (RAPD) . The result showed that there were some polymorphic DNA fragments of genomic DNA among haploid, the diploid parent strain HU-TY-1 and the original strain LK, some of them may be correlation with thermotolerant property.

Sheng Wu Gong Cheng Xue Bao, 2001 Sep, 17(5), 485 - 90
{Progress on the biosynthesis of medium-chain-length polyhydroxyalkanoates by microorganisms}; Yan Q et al.; Polyhydroxylkanoates(PHAs) are a class of polyesters produced as reserve materials by a large number of microorganisms under metabolic stress . The most fascinating feature of PHAs is its degradability, and which is supposed to take place of the traditional plastics made from petroleum in the future . PHAs are divided into two classes: short-chain-length PHAs(scl-PHAs) and medium-chain-length PHAs . mcl-PHAs is more welcome owing to its more wide crystallinity and higher extension to break than scl-PHAs, especially when some kind of new functional groups were incorporated into the side chain of the polyester . Since Psedumonas oleovorans is the most typical microorganism to produce mcl-PHAs, here the author summarized how P . oleovorans synthesize the mcl-PHAs and the production of mcl-PHAs by fermentation and give some of the idea about the future research of this field.

Arch Microbiol, 2001 Dec, 177(1), 107 - 12 Epub 2001 Oct 30.
A genetic screen for suppressors of Escherichia coli Tat signal peptide mutations establishes a critical role for the second arginine within the twin-arginine motif; Buchanan G et al.; The Escherichia coli Tat protein export pathway transports folded proteins synthesized with N-terminal twin-arginine signal peptides . Twin-arginine signal sequences contain a conserved SRRxFLK "twin-arginine" amino acid sequence motif which is required for protein export by the Tat pathway . The E . coli trimethylamine N-oxide reductase (TorA) is a Tat-dependent periplasmic molybdoenzyme that facilitates anaerobic respiration with trimethylamine N-oxide as terminal electron acceptor . Here, we describe mutant strains constructed with modified TorA twin-arginine signal peptides . Substitution of the second arginine residue of the TorA signal peptide twin-arginine motif with either lysine or aspartate, or the simultaneous substitution of both arginines with lysine residues, completely abolished export . In each case, the now cytoplasmically localised TorA retained full enzymatic activity with the artificial electron donor benzyl viologen . However, the mutant strains were incapable of anaerobic growth with trimethylamine N-oxide and the non-fermentable carbon-source glycerol . The growth phenotype of the mutant strains was exploited in a genetic screen with the aim of identifying second-site suppressor mutations that allowed export of the modified TorA precursors.

Int Dent J, 2001, 51(6 Suppl 1), 408 - 12
Dental considerations for dietary counselling; Duggal MS et al.; A decline in the prevalence of dental caries over three decades has occurred without a significant change in the consumption of fermentable carbohydrates, indicating that good dental health is achievable with the presence of cariogenic factors in the diet . Since, in many countries 80% of the caries is present in only 20% of the population, 'targeted intervention' would seem a better preventive option, stressing the judicious use of fluoride, plaque control, fissure sealants and a sensible diet . Dietary modification is notoriously difficult to achieve, being incumbent upon the subject's willingness to effect a change in behaviour . Many texts refer to the frequency of consumption of carbohydrates as being all-important, recommending a reduction in the frequency . However, recent evidence suggests it is the frequency of toothbrushing with a fluoride containing dentifrice which is of fundamental importance in promoting remineralisation of enamel . Dietary advice should be formulated which is both realistic and positive . Trying to dissuade children from consuming products, which they perceive to be tasty and pleasurable is counter productive and more emphasis should be given to tooth brushing using a fluoride toothpaste . Also, a fundamental shift away from the idea of 'good foods versus bad foods' is required and more emphasis laid on good diets as opposed to bad diets . Children should be able to enjoy foods traditionally considered 'bad' from a dental viewpoint, as long as they brush their teeth with a fluoride containing dentifrice and have a sensible approach to their consumption.

Acta Microbiol Immunol Hung, 2001, 48(3-4), 429 - 40
The biochemistry of citric acid accumulation by Aspergillus niger; Karaffa L et al.; Fungi, in particular Aspergilli, are well known for their potential to overproduce a variety of organic acids . These microorganisms have an intrinsic ability to accumulate these substances and it is generally believed that this provides the fungi with an ecological advantage, since they grow rather well at pH 3 to 5, while some species even tolerate pH values as low as 1.5 . Organic acid production can be stimulated and in a number of cases conditions have been found that result in almost quantitative conversion of carbon substrate into acid . This is exploited in large-scale production of a number of organic acids like citric-, gluconic- and itaconic acid . Both in production volume as well as in knowledge available, citrate is by far the major organic acid . Citric acid (2-hydroxy-propane-1,2,3-tricarboxylic acid) is a true bulk product with an estimated global production of over 900 thousand tons in the year 2000 . Till the beginning of the 20th century, it was exclusively extracted from lemons . Since the global market was dominated by an Italian cartel, other means of production were sought . Chemical synthesis was possible, but not suitable due to expensive raw materials and a complicated process with low yield . The discovery of citrate accumulation by Aspergillus niger led to a rapid development of a fermentation process, which only a decade later accounted for a large part of the global production . The application of citric acid is based on three of its properties: (1) acidity and buffer capacity, (2) taste and flavour, and (3) chelation of metal ions . Because of its three acid groups with pKa values of 3.1, 4.7 and 6.4, citrate is able to produce a very low pH in solution, but is also useful as a buffer over a broad range of pH values (2 to 7) . Citric acid has a pleasant acid taste which leaves little aftertaste . It sometimes enhances flavour, but is also able to mask sweetness, such as the aspartame taste in diet beverages . Chelation of metal ions is a very important property that has led to applications such as antioxidant and preservative . Moreover, it is a "natural" substance and fully biodegradable.

Acta Microbiol Immunol Hung, 2001, 48(3-4), 393 - 411
The glutathione metabolism of the beta-lactam producer filamentous fungus Penicillium chrysogenum; Pocsi I et al.; Glutathione (gamma-L-glutamyl-L-cysteinyl-glycine; GSH) shares structural similarities with the beta-lactam biosynthetic intermediate ACV-tripeptide (delta-(L-alpha-aminoadipyl)-L-cysteinyl-D-valine) . Not surprisingly, GSH has been reported to inhibit the beta-lactam biosynthetic machinery quite effectively and, hence, strategies to decrease the intracellular GSH concentrations without influencing negatively the physiological status of idiophasic mycelia would attract industrial interests . Here we present a detailed map of the GSH metabolic network of P . chrysogenum and show a promising way to keep the GSH pool selectively down under penicillin producing conditions . This procedure includes a well-controlled and transient lowering of pH at the beginning of the production phase, and it relies on the GSH-dependent detoxification of the protonophore penicillin side-chain precursors phenoxyacetic acid (POA) and phenylacetic acid (PA) . Encouraging preliminary fed-batch fermentation experiments have been performed to test this technological proposal . Interestingly, the mechanism of the activation of POA and PA to the appropriate CoA derivatives has remained yet to be answered but the involvement of GSH seems to be rather unlikely in this case . Our data also challenge the hypothesis that the formation of different kinds of penicillins would be an alternative to GSH-dependent detoxification processes in P . chrysogenum.

J Bacteriol, 2002 Feb, 184(3), 672 - 8
Novel pathway for alcoholic fermentation of delta-gluconolactone in the yeast Saccharomyces bulderi; van Dijken JP et al.; Under anaerobic conditions, the yeast Saccharomyces bulderi rapidly ferments delta-gluconolactone to ethanol and carbon dioxide . We propose that a novel pathway for delta-gluconolactone fermentation operates in this yeast . In this pathway, delta-gluconolactone is first reduced to glucose via an NADPH-dependent glucose dehydrogenase (EC 1.1.1.47) . After phosphorylation, half of the glucose is metabolized via the pentose phosphate pathway, yielding the NADPH required for the glucose-dehydrogenase reaction . The remaining half of the glucose is dissimilated via glycolysis . Involvement of this novel pathway in delta-gluconolactone fermentation in S . bulderi is supported by several experimental observations . (i) Fermentation of delta-gluconolactone and gluconate occurred only at low pH values, at which a substantial fraction of the substrate is present as delta-gluconolactone . Unlike gluconate, the latter compound is a substrate for glucose dehydrogenase . (ii) High activities of an NADP(+)-dependent glucose dehydrogenase were detected in cell extracts of anaerobic, delta-gluconolactone-grown cultures, but activity of this enzyme was not detected in glucose-grown cells . Gluconate kinase activity in cell extracts was negligible . (iii) During anaerobic growth on delta-gluconolactone, CO(2) production exceeded ethanol production by 35%, indicating that pyruvate decarboxylation was not the sole source of CO(2) . (iv) Levels of the pentose phosphate pathway enzymes were 10-fold higher in delta-gluconolactone-grown anaerobic cultures than in glucose-grown cultures, consistent with the proposed involvement of this pathway as a primary dissimilatory route in delta-gluconolactone metabolism.

Int J Food Microbiol, 2001 Dec 30, 71(2-3), 169 - 76
Survival and characterization of Escherichia coli strains in a typical Mexican acid-fermented food; Sainz T et al.; In this study, the presence and pathogenic characteristics of Escherichia coli strains in pozol, an acid-fermented maize beverage consumed in South-eastern Mexico, were determined . Seventy-three E . coli strains were isolated at early and late times (6 and 48 h) during the pozol fermentation process, when pH values of the doughs were 6.7-4.7 (6 h) and 4.7-3.7 (48 h) . Serotypes that belong to diarrheagenic E . coli serogroups O18, O88, O8, O11, O20, O173 were identified . HEp-2 cell adherence in vitro assays showed localized, diffuse and aggregative adherence patterns among some of these strains . A DNA colony hybridization analysis with different probes showed the presence of virulence genes related to diarrheal pathogenesis . Thirty-three percent of the E . coli strains were tetracycline-resistant and 95% had a 20 kb plasmid . The presence and survival of potentially pathogenic E . coli in acid-fermented pozol suggest that such foods may be a potential source of foodborne outbreaks.

Reprod Nutr Dev, 2001 Jul-Aug, 41(4), 297 - 308
Variation of proteolytic activity in ewe during in vivo digestion of two pea-based diets differing by their fermentability characteristics; Sales-Duval M et al.; In order to study the effects of a small difference in starch and nitrogen availability on proteolysis, two different diets were supplied to four ewes fitted with rumen fistulae . They differed in the ratio of fermentable nitrogen over fermentable energy . with 144 g of fermentable nitrogen (FN) per kg of fermentable energy (FE) for diet I and 126 g FN x kg(-1) FE for diet II . The diets were constituted of 700 g hay grass, 200 g ground pea and either 100 g ground wheat (diet I) or 100 g corn starch (diet II) . After two weeks of an adapting period to the diets, rumen content was sampled after feeding over time . The rate of disappearance of soluble proteins was 2.5 times higher with diet II and ammonia concentrations were significantly lower (from -28 to -43%) with diet II . Total proteolytic activity, by considering all the bacterial compartments, was significantly higher with diet II (+40 EU/mL x h(-1)): changes in the total proteolytic activity in the particulate and the liquid phases of the rumen could explain the difference observed between the two diets . Moreover, with diet II, exopeptidase activities increased more in the liquid phase, especially leucine aminopeptidase and Dipeptidyl peptidase I (DPP-I), and the diversity of endopeptidase activities increased in the particulate phase . These two facts could account for the higher total proteolytic activity in the rumen content with diet II.

Biotechnol Bioeng, 2002 Mar 5, 77(5), 589 - 98
Production of teicoplanin by Actinoplanes teichomyceticus in continuous fermentation; Vara AG et al.; Production of the potent antibiotic teicoplanin by Actinoplanes teichomyceticus was studied in batch and in chemostat cultures . It is found that the producing strain deactivates to a non-producing strain named NP-12 . This strain is used to find the growth kinetics of the A . teichomyceticus without interference from the product teicoplanin . In batch experiments with NP-12 grown on glucose at different initial concentrations and with different added amounts of teicoplanin, the strong inhibitory effect of teicoplanin was determined . These results obtained on NP-12 were validated in a series of chemostat experiments with the processing strain . All experiments in batch and in chemostat cultures were well represented by Monod kinetics with respect to the carbon and energy source (glucose) and with a substantial inhibitory effect of teicoplanin . Further experiments were made with the producing strain in a continuous reactor coupled to a microfilter that delivers a cell-free permeate . It was found that the derived kinetics almost exactly simulated the behavior of the cell recirculation reactor in addition to when the cell concentration in the reactor was more than four times higher than in the chemostat . For industrial production of teicoplanin, a continuous reactor with cell recirculation and working with a low effluent glucose concentration was by far the best mode of operation . Finally, the deactivation of the producing strain to NP-12 was modeled by a two-step deactivation mechanism . Deactivation was independent of dilution rate but dependent on the inoculum preparation and on the previous history of the inoculum .

J Biol Chem, 2002 Mar 29, 277(13), 10973 - 81 Epub 2002 Jan 11.
Uptake of exogenous coenzyme Q and transport to mitochondria is required for bc1 complex stability in yeast coq mutants; Santos-Ocana C et al.; Coenzyme Q (Q) is an essential component of the mitochondrial respiratory chain in eukaryotic cells but also is present in other cellular membranes where it acts as an antioxidant . Because Q synthesis machinery in Saccharomyces cerevisiae is located in the mitochondria, the intracellular distribution of Q indicates the existence of intracellular Q transport . In this study, the uptake of exogenous Q(6) by yeast and its transport from the plasma membrane to mitochondria was assessed in both wild-type and in Q-less coq7 mutants derived from four distinct laboratory yeast strains . Q(6) supplementation of medium containing ethanol, a non-fermentable carbon source, rescued growth in only two of the four coq7 mutant strains . Following culture in medium containing dextrose, the added Q(6) was detected in the plasma membrane of each of four coq7 mutants tested . This detection of Q(6) in the plasma membrane was corroborated by measuring ascorbate stabilization activity, as catalyzed by NADH-ascorbate free radical reductase, a transmembrane redox activity that provides a functional assay of plasma membrane Q(6) . These assays indicate that each of the four coq7 mutant strains assimilate exogenous Q(6) into the plasma membrane . The two coq7 mutant strains rescued by Q(6) supplementation for growth on ethanol contained mitochondrial Q(6) levels similar to wild type . However, the content of Q(6) in mitochondria from the non-rescued strains was only 35 and 8%, respectively, of that present in the corresponding wild-type parental strains . In yeast strains rescued by exogenous Q(6), succinate-cytochrome c reductase activity was partially restored, whereas non-rescued strains contained very low levels of activity . There was a strong correlation between mitochondrial Q(6) content, succinate-cytochrome c reductase activity, and steady state levels of the cytochrome c(1) polypeptide . These studies show that transport of extracellular Q(6) to the mitochondria operates in yeast but is strain-dependent . When Q biosynthesis is disrupted in yeast strains with defects in the intracellular transport of exogenous Q, the bc(1) complex is unstable . These results indicate that delivery of exogenous Q(6) to mitochondria is required fore activity and stability of the bc(1) complex in yeast coq mutants.

Life Sci, 2001 Nov 30, 70(2), 219 - 27
Fermented soybean-derived Touchi-extract with anti-diabetic effect via alpha-glucosidase inhibitory action in a long-term administration study with KKAy mice; Fujita H et al.; A water-soluble Touchi-extract (TE) exerts a potent inhibitory activity against rat intestinal alpha-glucosidase in foodstuffs, and elicited anti-glycemic effects in rats and humans with single-bolus oral administration . In the present study, genetically modified diabetic model KKAy mice were used to examine the long-term effects of TE . Eight-week-old male KKAy mice were fed with CE-2 chow containing 0.08 and 0.4% of TE for 60 days . In the latter group, fasting blood glucose levels decreased (6.68 +/- 0.41 mmol/L) significantly (p<0.05) after a 60-day ingestion period compared with controls (8.75 +/- 0.54 mmol/L) . Moreover, postprandial blood glucose levels were also significantly reduced (16.79 +/- 2.28 mmol/L; p<0.01) after ingesting TE for only 30 days compared with controls (28.49 +/- 0.59 mmol/L) . On oral TE treatment for 60 days, postprandial increases in the blood glucose level after oral loading of sucrose (2 g/kg) at 30 (p<0.05) and 60 (p<0.01) min were significantly depressed compared with controls . Indexes for serum lipids; viz., total cholesterol (p<0.05) and triglyceride (p<0.01) levels significantly decreased after TE ingestion . Indexes for hepatic functions, such as glutamic-oxaloacetic transaminase (p<0.01), glutamic-pyruvic transaminase and gama-glutamyl transpeptide levels, were similarly suppressed . Organ weights of the heart, kidney, jejunum, liver and spleen increased in control KKAy mice due to hyperinsulinemia . Interestingly, the respective organ weights decreased (p<0.05, 0.01) and the jejunum length was reduced (p<0.05) significantly in the TE-treated groups . All in all, TE demonstrated an anti-hyperglycemic effect and may have potential use in the management of non-insulin-dependent diabetic mellitus.

Bioseparation, 2001, 10(1-3), 87 - 97
Direct product sequestration of a recombinant cutinase from batch fermentations of Saccharomyces cerevisiae; Calado CR et al.; The recovery of cutinase of Fusarium solani pisi produced by the yeast Saccharomyces cerevisiae was studied in a fluidised bed adsorption system directly integrated with a productive fermenter (so-called direct product sequestration; DPS) . The relative efficiency of this system was compared with the one of a conventional purification process by discrete sequences of fermentation, broth clarification, ultrafiltration and fixed bed anion exchange chromatography . By direct product sequestration of the extracellular heterologous cutinase it was possible, through only one unit operation: (i) to perform broth clarification, (ii) to obtain a high cutinase concentration factor, and (iii) to recover cutinase with a specific activity that equalled that obtained with the conventional purification process . It was also possible (iv) to substantially reduce the total process time, (v) to improve the overall yield, and (vi) to increase cutinase productivity . Furthermore, the procedure outlined is suitable for large scale bioprocess exploitation.

Biotechnol Bioeng, 2002 Feb 15, 77(4), 420 - 9
Hybrid model building methodology using unsupervised fuzzy clustering and supervised neural networks; Ronen M et al.; This paper suggests a model building methodology for dealing with new processes . The methodology, called Hybrid Fuzzy Neural Networks (HFNN), combines unsupervised fuzzy clustering and supervised neural networks in order to create simple and flexible models . Fuzzy clustering was used to define relevant domains on the input space . Then, sets of multilayer perceptrons (MLP) were trained (one for each domain) to map input-output relations, creating, in the process, a set of specified sub-models . The estimated output of the model was obtained by fusing the different sub-model outputs weighted by their predicted possibilities . On-line reinforcement learning enabled improvement of the model . The determination of the optimal number of clusters is fundamental to the success of the HFNN approach . The effectiveness of several validity measures was compared to the generalization capability of the model and information criteria . The validity measures were tested with fermentation simulations and real fermentations of a yeast-like fungus, Aureobasidium pullulans . The results outline the criteria limitations . The learning capability of the HFNN was tested with the fermentation data . The results underline the advantages of HFNN over a single neural network .

Pol J Pharmacol, 2001 May-Jun, 53(3), 201 - 14
Drug addiction . Part I . Psychoactive substances in the past and presence; Vetulani J; Substances capable of changing the functions of the central nervous system are widely distributed in plant kingdom, and many of them were discovered by ancient food-gatherers at the dawn of humanity . In the Old World only a few substances producing euphoria or altered states of consciousness and having habit-forming properties are still widely used . They are the products of poppy (opium, morphine), hemp (hashish, marijuana), and of fermentation of various organic materials alkohol . This list has recently been joined by the psilocybin-containing mushrooms . The addiction-forming compounds originated in the New World and widely spread are tobacco (nicotine) and cocaine . In the 19th and 20th, century the development of medicinal chemistry resulted in several synthetic compounds, originally proposed as therapeutics, such as barbiturates, benzodiazepines and amphetamines . Due to legal problems, to avoid production of the substances already prohibited, many designer drugs were manufactured . In addition, several compounds were synthesized as recreational drugs . Also some compounds that were not regarded as drugs, such as aromatic hydrocarbons and other cleansing agents, as well as steroids were found to have properties of dangerous, habit-forming agents . The attitude of society and the pattern of use of psychoactive substances have changed with time, particularly in the last decades . The active principles are now more addictive because of concentration, purification, chemical modifications and the way of ingestion, which now favors most rapid transport to the central nervous system . The substance abuse approaches the level of global epidemics, and the recent usage of drugs of addition is also reviewed.

Public Health Nutr, 2001 Oct, 4(5), 943 - 52
Dietary soy isoflavone intake in older Japanese American women; Rice MM et al.; OBJECTIVE: In a sample of older Japanese American women, we aimed to: (1) describe the most commonly consumed soy foods, (2) estimate dietary soy isoflavone intake, (3) describe characteristics associated with dietary soy isoflavone intake, and (4) compare our estimates with previously published estimates in other Japanese samples . DESIGN: A 14-item soy food-frequency questionnaire was administered to older Japanese American women and responses were converted to quantitative estimates of soy isoflavones (genistein plus daidzein) . Multiple regression was used to examine characteristics associated with dietary soy isoflavone intake, including self-reported lifestyle and cultural factors and dietary intake of various foods ascertained from a semi-quantitative food-frequency questionnaire . To compare our estimates with other samples, a review of the literature was conducted . SETTING/SUBJECTS: Data are from 274 women aged 65+ years, recruited from a longitudinal cohort study of Japanese Americans in King County, Washington State . RESULTS: The soy foods most commonly consumed were tofu (soybean curd), miso (fermented soybean paste) and aburaage (fried thin soybean curd) . The mean intake of dietary soy isoflavones was 10.2 (standard deviation (SD), 12.4) mg day(-1), approximately a quarter to a half that of previously published estimates in Japanese samples . Dietary soy isoflavone intake was positively associated with speaking Japanese, the consumption of traditional Japanese dishes (kamaboko, manju and mochi), low-fat/non-fat milk and yellow/red vegetables, vitamin E supplement use, and walking several blocks each day . Dietary soy isoflavone intake was negatively associated with the consumption of butter . CONCLUSIONS: The estimated dietary soy isoflavone intake in Japanese American women living in King County, Washington State was about a quarter to a half that of women living in Japan . Dietary soy isoflavone intake was associated with speaking Japanese and healthy lifestyle and dietary habits.

Appl Biochem Biotechnol, 2001 Oct-Dec, 96(1-3), 71 - 82
Semi-solid-state fermentation of Eicchornia crassipes biomass as lignocellulosic biopolymer for cellulase and 3-glucosidase production by cocultivation of Aspergillus niger RK3 and Trichoderma reesei MTCC164; Kumar R et al.; An aquatic weed biomass, Eicchornia crassipes, present in abundance and leading to a threatening level of water pollution was used as substrate for cellulase and beta-glucosidase production using wild-type strain Aspergillus niger RK3 that was isolated from decomposing substrate . Alkali treatment of the biomass (10%) resulted in a 60-66% increase in endoglucanase, exoglucanase, and beta-glucosidase production by the A . niger RK3 strain in semi-solid-state fermentation . Similarly, the alkali-treated biomass led to a 45-54% increase in endo- and exoglucanase and a higher (98%) increase in beta-glucosidase production by Trichoderma reesei MTCC164 under similar conditions . However, the cocultivation of A . niger RK3 and T . reesei MTCC164 at a ratio of 3:1 showed a 20-24% increase in endo- and exoglucanase activities and about a 13% increase in the beta-glucosidase activity over the maximum enzymatic activities observed under single culture conditions . Multistep physical (ultraviolet) and chemical (N-methyl-N'-nitrosoguanidine, sodium azide, colchicine) mutagenesis of the A . niger RK3 strain resulted in a highly cellulolytic mutant, UNSC-442, having an increase of 136, 138, and 96% in endoglucanase, exoglucanase, and beta-glucosidase, activity, respectively . The cocultivation of mutant UNSC-442 along with T . reesei MTCC164 (at a ratio of 3:1) showed a further 10-11% increase in endo- and exoglucanase activities and a 29% increase in beta-glucosidase activity in semi-solid-state fermentation.

Eur J Clin Microbiol Infect Dis, 2001 Nov, 20(11), 765 - 9
Bacteremia due to Leptotrichia trevisanii sp . nov; Tee W et al.; A thin, filamentous, non-motile, aerotolerant, anaerobic, gram-negative bacterium was isolated from the blood of a 46-year-old man who was diagnosed as having acute myeloid leukemia . The organism had a positive catalase reaction but was negative in indole and oxidase tests . A commercially available system failed to identify the bacterium, but 16S rRNA gene sequencing showed it to be most closely related (97% similarity) to a recently isolated Leptotrichia sp . The DNA base composition was 29.7% mol G+C, and the organism produced lactate as the sole end-product of glucose fermentation . These data indicate the isolate is a new species of Leptotrichia for which the name Leptotrichia trevisanii sp . nov . is proposed.

EMBO J, 2002 Jan 15, 21(1-2), 135 - 44
Acute glucose starvation activates the nuclear localization signal of a stress-specific yeast transcription factor; Gorner W et al.; In yeast, environmental conditions control the transcription factor Msn2, the nuclear accumulation and function of which serve as a sensitive indicator of nutrient availablity and environmental stress load . We show here that the nuclear localization signal (NLS) of Msn2 is a direct target of cAMP-dependent protein kinase (cAPK) . Genetic analysis suggests that Msn2-NLS function is inhibited by phosphorylation and activated by dephosphorylation . Msn2-NLS function is unaffected by many stress conditions that normally induce nuclear accumulation of full-length Msn2 . The Msn2-NLS phosphorylation status is, however, highly sensitive to carbohydrate fluctuations during fermentative growth . Dephosphorylation occurs in >2 min after glucose withdrawal but the effect is reversed rapidly by refeeding with glucose . This response to glucose depletion is due to changes in cAPK activity rather than an increase in protein phosphatase activity . Surprisingly, the classical glucose-sensing systems are not connected to this rapid response system . Our results further imply that generic stress signals do not cause short-term depressions in cAPK activity . They operate on Msn2 by affecting an Msn5-dependent nuclear export and/or retention mechanism.

EMBO J, 2002 Jan 15, 21(1-2), 43 - 52
Shy1p is necessary for full expression of mitochondrial COX1 in the yeast model of Leigh's syndrome; Barrientos A et al.; SHY1 codes for a mitochondrial protein required for full expression of cytochrome oxidase (COX) in Saccharomyces cerevisiae . Mutations in the homologous human gene (SURF1) have been reported to cause Leigh's syndrome, a neurological disease associated with COX deficiency . The function of Shy1p/Surf1p is poorly understood . Here we have characterized revertants of shy1 null mutants carrying extragenic nuclear suppressor mutations . The steady-state levels of COX in the revertants is increased by a factor of 4-5, accounting for their ability to respire and grow on non-fermentable carbon sources at nearly wild-type rates . The suppressor mutations are in MSS51, a gene previously implicated in processing and translation of the COX1 transcript for subunit 1 (Cox1) of COX . The function of Shy1p and the mechanism of suppression of shy1 mutants were examined by comparing the rates of synthesis and turnover of the mitochondrial translation products in wild-type, mutant and revertant cells . We propose that Shy1p promotes the formation of an assembly intermediate in which Cox1 is one of the partners.

J Agric Food Chem, 2002 Jan 16, 50(2), 357 - 60
Monoacylglycerol from Punica granatum seed oil; Fatope MO et al.; The seeds of Punica granatum, known as hap roman in the Arabian Peninsula, are commonly eaten as a dessert . As part of an ongoing project to find nonnutritional natural products which have health benefits, or that can be exploited to protect crops, the chloroform-soluble extract of the fermented seeds of P . granatum was found to be rich in 1-O-trans,cis,trans-9,11,13-octadecatrienoyl glycerol (1) . The seed oil is not lethal to brine shrimp larvae . 1-O-isopentyl-3-O-octadec-2-enoyl glycerol (2) and the known cis-9-octadecenoic, octadecanoic, and eicosanoic acids were also detected in small amounts in the seed oil by LC and MS . The structure of 1 was determined from NMR and MS spectral data.

Biochim Biophys Acta, 2001 Dec 30, 1522(3), 175 - 86
The modulation of the biological activities of mitochondrial histone Abf2p by yeast PKA and its possible role in the regulation of mitochondrial DNA content during glucose repression; Cho JH et al.; The mitochondrial histone, Abf2p, of Saccharomyces cerevisiae is essential for the maintenance of mitochondrial DNA (mtDNA) and appears to play an important role in the recombination and copy number determination of mtDNA . Abf2p, encoded by a nuclear gene, is a member of HMG1 DNA-binding protein family and has two HMG1-Box domains, HMG1-Box A and B . To investigate the role of Abf2p in the control of mtDNA copy number, we asked if the in vivo functions of Abf2p are regulated by the possible modification such as phosphorylation . We found that the N-terminal extended segment (KRPT(21)S(22)) of HMG1-Box A is rapidly and specifically phosphorylated by cAMP-dependent protein kinase (PKA) in vitro . The phosphorylation in this region inhibits the binding of Abf2p to all kinds of DNA including four-way junction DNA and the supercoiling activity of Abf2p itself . The abf2 mutant cells with an abf2(T21A/S22A) allele defective in the phosphorylation site have a severe defect in the regulation of mtDNA content during glucose repression in vivo . These observations suggest that the phosphorylation via PKA, that is activated during glucose repression, may regulate the in vivo functions of Abf2p for the control of mtDNA content during shift from gluconeogenic to fermentative growth.

Appl Microbiol Biotechnol, 2001 Dec, 57(5-6), 738 - 43
Metabolic study of the adaptation of the yeast Candida guilliermondii to sugarcane bagasse hydrolysate; Sene L et al.; Batch xylitol production from concentrated sugarcane bagasse hydrolysate by Candida guilliermondii was performed by progressively adapting the cells to the medium . Samples were analyzed to monitor sugar and acetic acid consumption, xylitol, arabitol, ethanol, and carbon dioxide production, as well as cell growth . Both xylitol yield and volumetric productivity remarkably increased with the number of adaptations, demonstrating that the more adapted the cells, the better the capacity of the yeast to reduce xylose to xylitol in hemicellulose hydrolysates . Substrate and product concentrations were used in carbon material balances to study in which way the different carbon sources were utilized by this yeast under microaerobic conditions, as well as to shed light on the effect of the progressive adaptation to the medium on its fermentative activity . Such a theoretical means allowed estimation for the first time of the relative contribution of each medium component to the formation of the main products of this fermentation system.

Appl Microbiol Biotechnol, 2001 Dec, 57(5-6), 717 - 24
Major proteins related to chlortetracycline biosynthesis in a Streptomyces aureofaciens production strain studied by quantitative proteomics; Li XM et al.; Changes in synthesis and abundance of proteins associated with chlortetracycline (CTC) production in Streptomyces aureofaciens were investigated by two-dimensional polyacrylamide gel electrophoresis of proteins pulse-labelled in vivo with L-{35S}methionine . Eleven individual protein spots were selected as being related to formation of the antibiotic . Expression of these prominent proteins was not observed in the non-producing mutant; moreover, they were overexpressed in cultures grown in the presence of benzyl thiocyanate, a specific stimulator of CTC biosynthesis used in industrial fermentations . The expression kinetics of the selected proteins was assessed using the technique of computer-assisted image analysis with the EQIAS software and the elongation factor Tu as an internal standard . Interestingly, the kinetic profiles were generally not identical . including those of anhydrotetracycline monooxygenase and the 13-kDa subunit of tetracycline dehydrogenase, two enzymes involved, in the terminal sequential steps of the CTC biosynthetic pathway . The presence of more forms of these enzymes with different charge characteristics was observed . The data presented demonstrated how dramatically the industrial microorganism can change its protein repertoire during the production phase; at least five proteins were nearly comparable in level to the most prominent proteins, exemplified by elongation factor Tu.

Appl Microbiol Biotechnol, 2001 Dec, 57(5-6), 674 - 9
An improved procedure for production of human epidermal growth factor from recombinant E . coli; Tong WY et al.; An improved procedure for the fermentation and purification of human epidermal growth factor (hEGF) was developed . Recombinant Escherichia coli HB-101 {lacUV5omp08hEGF} harboring plasmid lacUV5omp08hEGF encoding hEGF was used in fermentation to increase levels of hEGF . Medium composition, and the levels of inoculum, inducer (isopropyl-beta-D-thiogalactoside) and ampicillin were optimized with respect to volumetric fermentation of hEGF . As a result, the hEGF concentration reached a high value of 242 mg l(-1) and the amount of heterogeneous protein decreased by 62% compared with that before optimization in batch fermentation . High-quality hEGF was purified from the fermentation culture by centrifugation, salting-out, resuspension, recentrifugation and finally gel chromatography on a Grad-iFrac System using Sephadex G-50 superfine . The purity of hEGF and the total yield were more than 94% and higher than 36%, respectively, and SDS-PAGE of the purified hEGF demonstrated a single band corresponding to an hEGF standard . In particular, a very important phenomenon was found, i.e . that the amount of heterogenous protein in fermentation broths cultured in media with high concentrations of lactose is far less than that cultured in media with high concentrations of glucose.

Yakushigaku Zasshi, 2001, 36(1), 70 - 5
{Forgotten episodes of the birth of cortisone}; Uchibayashi M; During World War II, a rumor reached the United States and the United Kingdom that the Germans were successfully using an adrenal hormone product to protect Luftwaffe pilots from the adverse effects of high altitudes . The product was said to be obtained from adrenal glands collected in a huge amount in Argentina and transported by U-boats to Germany . The U . S . and the U . K . exerted their war efforts by setting up urgent research projects to produce similar products . The war ended in 1945, however, before the goal was achieved . The German rumor turned out to be groundless . Cortisone acquired fame in 1949 as "a miracle drug" for the relief of rheumatic pain . Its therapeutic discovery was an outcome of the untenable assumption that rheumatoid arthritis patients must have suffered from adrenal insufficiency and hormone deficiency . The war efforts have led to successful syntheses of cortisone after the war, and its industrial production has reduced its cost drastically from $200.00 per gram in 1949 to $10.00 in 1951 . To overcome the cumbersome synthetic routes for cortisone, natural product sources were sought as possible starting materials, but without much success . A microbiological transformation of steroidal compounds was developed in 1952 to introduce an oxygen function into the molecular position 11 by a microorganism found at a window of a laboratory . The fermentation process required progesterone which found its timely supply in Mexico . The cost of progesterone went down from $2.00 per gram to $0.15 and that of cortisone further from $10.00 to $3.50 in 1955 . An ample supply of cortisone at an affordable price was admirably achieved by the combination of progesterone derived from diosgenin of the Mexican yam and a microbiological oxidation process developed by a chance discovery of suitable organisms . The former is attributed to R . E . Marker and the latter to D . H . Peterson.

Bull Soc Pathol Exot, 2000 Jan, 93(5), 365 - 71
{Edmond Sergent (1876-1969) and the Pasteur Institute of Algeria}; de la Tribonniere X; Edmond Sergent, supported by a distinguished team of colleagues, directed the Pasteur Institute of Algeria for over 60 years, from 1900 to 1963 . As a student of Emile Roux, Sergent had received a Pasteurian training . His institute devoted extensive study to malaria . Sergent defined the concept of prevention and extended it to other pathologies . For many years, the Institute persevered in carrying out successful antimalarial campaigns such that Algeria was freed of the disease . In 1916-1917, Sergent and his brother were called upon to organise anti-malarial efforts for the Armee d'Orient . By way of systematic and energetic curative and prophylactic measures, they were able to eradicate the disease . In 1908, the Sergent brothers were the first to discover the role of the louse in the transmission of another disease, relapsing fever . The Pasteur Institute team also discovered the sand fly vector which transmits the parasite causing leishmaniasis . The Sergents found a new form of oculonasal myiasis, called "Thimni" . In addition, they led effective campaigns against tuberculosis based on BCG vaccination administered throughout Algeria . The Pasteur Institute of Algeria conducted important research in plant and animal diseases . For example, they detected a trypanosome agent causing dromedary "debab", as well as its vector, the horsefly . They also studied in depth bovine piroplasmosis, which causes widespread and destructive disease, and demonstrated the role of the tick in promoting transmission generally . Their work in botany included the discovery that a Fusarium-type fungus was the causal agent for "baioudh", the main disease of date palms . They also demonstrated the basic role of the fruit fly in alcoholic grape fermentation.

Chin Med J (Engl), 2000 Jan, 113(1), 44 - 8
Cloning of Chinese obese cDNA and its expression in E . coli; Qi K et al.; OBJECTIVE: To obtain the sequence of Chinese obese (OB) cDNA and establish a method of leptin production in China . METHODS: Han Chinese OB cDNA fragment was obtained by reverse transcriptase-polymerase chain reaction (RT-PCR) with total RNA extracted from human adipocytes and was inserted into the expressing vector pBV220 . Then the constructed recombinant plasmid pBV220-OB was transformed to E . coli DH5 alpha for leptin expression . The recombinant expressing system was confirmed by restriction endonuclease digestion, DNA sequencing and protein expression . E . coli cells were lysed by high-pressure homogenization . After cell membrane was extracted, the inclusion bodies were mainly renatured and purified primarily by precipitation with ammonium sulfate and gel chromatography through a Sephadex G75 column . The activity of recombinant leptin was determined by its influence on the satiety and weight gain of mice . RESULTS: Analysis of DNA sequence showed that Han Chinese OB cDNA included the glutamine codon at 49 . The amount of recombinant leptin expressed in E . coli accounted for 31%-47% of total cellular proteins . From 1 L of fermentative bacteria about 40 mg of pure recombinant human leptin was isolated with a purity of being above 95% . The recombinant human leptin could reduce food intake and inhibit weight gains in mice . CONCLUSION: The glutamine codon at 49 is not missing in Chinese OB gene . The biologically active human leptin can be obtained by a relatively simple method of recombinant DNA technology.

J Ind Microbiol Biotechnol, 2001 Dec, 27(6), 399 - 402
Genes for the biosynthesis of spinosyns: applications for yield improvement in Saccharopolyspora spinosa; Madduri K et al.; Spinosyns A and D are the active ingredients in an insect control agent produced by fermentation of Saccharopolyspora spinosa . Spinosyns are macrolides with a 21-carbon, tetracyclic lactone backbone to which the deoxysugars forosamine and tri-O-methylrhamnose are attached . The spinosyn biosynthesis genes, except for the rhamnose genes, are located in a cluster that spans 74 kb of the S . spinosa genome . DNA sequence analysis, targeted gene disruptions and bioconversion studies identified five large genes encoding type I polyketide synthase subunits, and 14 genes involved in sugar biosynthesis, sugar attachment to the polyketide or cross-bridging of the polyketide . Four rhamnose biosynthetic genes, two of which are also necessary for forosamine biosynthesis, are located outside the spinosyn gene cluster . Duplication of the spinosyn genes linked to the polyketide synthase genes stimulated the final step in the biosynthesis--the conversion of the forosamine-less pseudoaglycones to endproducts . Duplication of genes involved in the early steps of deoxysugar biosynthesis increased spinosyn yield significantly.

J Ind Microbiol Biotechnol, 2001 Dec, 27(6), 368 - 77
Genetic approaches for controlling ratios of related polyketide products in fermentation processes; Cropp A et al.; Simple acyl thioesters are used as precursors for both the initiation and elongation steps in polyketide biosynthetic processes . Several structurally related polyketide products are sometimes made in these processes . These analogs are typically generated by a combination of two factors: availability of structurally similar biosynthetic precursors, and biosynthetic enzymes unable to effectively discriminate between them . Often, only one polyketide product is desired from a fermentation process, requiring a method to control the ratio of these different analogs . Preferential production of one desired analog is accomplished using random mutagenesis and manipulation of fermentation conditions . A genetic enzymatic understanding of polyketide biosynthesis, as well as the pathways that provide the relevant precursors, allows for a rational and more contemporary approach for control of analogs produced in fermentation processes . This approach involves genetic manipulation of either the pathways that provide pools of the acyl CoA thioester precursors, or the function/specificity of the appropriate biosynthetic enzymes . Reviewed herein are three such examples where these approaches have been carried out successfully with polyketide biosynthetic processes.

Prikl Biokhim Mikrobiol, 2001 Nov-Dec, 37(6), 694 - 7
{Biosynthesis of pectinase by fungi Bjerkandera and Coriolus by solid phase fermentation}; Ganbarov KhB et al.; Production of an extracellular pectinase by wood-rot fungi of the genus Bjerkandera and Coriolus was studied . The active producers B . adusta 40 and C . versicolor 24 were selected . The dynamics of production of pectinase and effects of temperature, initial pH, humidity of the medium and addition of nitrogen sources on the biosynthesis of pectinase were studied.

Acta Pharm Hung, 2001, 71(1), 7 - 12
{History and major achievements of the Institute for Drug Research}; Simay A; The Institute for Drug Research (IDR) was established in 1950, as state-funded central research and development institution, with the aim of integrating the limited research capacity of post-war Hungary, and of providing products and technologies for the whole Hungarian pharmaceutical industry . Following various transformations, since October 1999 IDR has become a fully-owned subsidiary and major R&D institution of IVAX Corporation, headquartered in Miami, Florida . Early activities of IDR have focused on elaborating non-infringing technologies for the industrial production of pharmaceutical active ingredients of both synthetic and fermentation origin . By developing over 70 industrial technologies IDR has made significant contributions to the revitalization of the post-war Hungarian pharmaceutical industry . It has also played decisive role in the establishment and development of certain novel branches of this industry, e.g . fermentation production of antibiotics and steroids, peptide chemistry, steroid chemistry, etc . Original research targeting discovery and development of new chemical entities has become an integral part of IDR's activity since the mid-fifties . Of the several discoveries in various fields of biological activity 12 new drugs have become registered and marketed by Hungarian pharmaceutical companies . The industry-oriented R&D activity of IDR is hall-marked by the more than 800 patents field and registered during its history . Furthermore, over 2000 scientific communications and around 350 books, book-chapters and other scientific publications illustrate also its contribution to the domestic and international scientific community.

J Dairy Sci, 2001 Nov, 84(11), 2486 - 93
Differences in yields of microbial crude protein from in vitro fermentation of carbohydrates; Hall MB et al.; The yield of microbial crude protein (CP) from carbohydrate fermentations was examined using trichloroacetic acid (TCA) precipitation of batch cultures . The medium contained ammonium bicarbonate, casein acid hydrolysate, and cysteine hydrochloride as nitrogen sources . Isolated bermudagrass neutral detergent fiber (iNDF) and 60:40 blends of iNDF and sucrose (Suc), citrus pectin (Pec), or corn starch (Sta) (approximately 375 mg of substrate organic matter/vial) were fermented in vitro in two separate fermentation runs with mixed ruminal microbes . Three fermentation tubes for each substrate were destructively sampled at 0, 4, 8, 12, 16, 20, and 24 h . Fermented samples were precipitated at a concentration of 19.4% TCA, and filtered to collect unfermented iNDF and precipitate . Collected residues were analyzed for CP as Kjeldahl N x 6.25 . Microbial CP (TCACP) was estimated as TCA-precipitated CP corrected for the TCA-precipitated CP content of substrates at 0 h, and the mean of fermentation blanks from each hour . Medium pH did not decline below 6.49 in any fermentation tube . Comparisons of maximal yields based on the hour in which the measured mean yield was greatest for each substrate in each fermentation indicated that Sta > Suc = Pec > iNDF (P < 0.05) . All substrates showed increases in TCACP to their maxima, followed by declines in TCACP . This likely reflects the relative dominance of production or degradation of microbes about the point of substrate limitation . Unlike other substrates, Suc had no detectable lag, and presented a more persistent TCACP yield curve than the other non-NDF carbohydrates (NFC) . Regression analysis of TCACP yield over time for iNDF versus other substrates, Pec + Sta versus Suc, and Pec versus Sta indicated that the compared curves were not parallel (P < 0.05) . The patterns of TCACP yield over time were cubic for iNDF and Suc, and quartic for Pec and Sta . The maximal yields of TCACP predicted from the regressions were Sta: 34.0 mg at 15.6 h, Pec: 29.9 mg at 13.5 h, Suc: 25.5 mg at 12.6 h, and iNDF: 13.6 mg at 19.3 h . The NDF and NFC carbohydrates examined differed in both maximal yields and temporal patterns of yield of TCACP.

Water Res, 2002 Jan, 36(1), 230 - 8
Real-time control of an immobilized-cell reactor for wastewater treatment using ORP; Chen KC et al.; The performance of an immobilized-cell reactor for simultaneous carbon nitrogen removal in synthetic wastewater with an intermittent aeration (IA) process under real-time control of oxygen supply was investigated . The oxidation-reduction potential (ORP) was monitored during operation . The ORP-time profile showed distinctive turning points . which directly correlated with the changes in the system chemistry and biological activity . The reactor was conducted by cyclic fixed-time aeration nonaeration operation at the beginning, followed by real-time control technology using ORP setpoint . A moving window along the slope of the ORP curve was employed to search for the nitrate breakpoint of the aeration cycle . Once the breakpoint was found, the reactor was aerated for a fixed period . The treatment process could effectively avoid the anoxic fermentation state under the real-time control . The cycle time was reduced around 30% . The duration of aeration period was found to be optimum at 3 h under the consideration of the removal efficiencies of COD and total nitrogen . The real-time control system not only exhibited a better nitrogen removal efficiency than the fixed-time control operation, but it also showed a stable effluent quality during the change of HRT from 3 to 8 h . Good operation stability was demonstrated even when a very high disturbance of the influent loading occurred.

Usp Fiziol Nauk, 2001 Oct-Dec, 32(4), 36 - 59
{Regulation and self-regulation of the pancreas secretion}; Korot'ko GF et al.; A review of modern experimental and clinical research, including own author's data, on regulation of the periodical and postprandial external pancreas secretion and of the secretion phases . Focus on self-regulation of pancreas exosecretion with the pancreatic enzymes based on the principle of negative feedback, and on mechanisms of the feedback inhibition of pancreatic secretion . Description of the selective and generalised inhibition of secretion of pancreatic enzymes, the role of this mechanism in emergency adaptation of the fermental spectrum of the pancreas secretion in response to the nutritional composition and properties of the duodenal chemus . In conclusion, the experimental and clinical data are presented on use of intraduodenal injection of trypsin as a generalised inhibitor of pancreas secretion in case of acute pancreatitis.

Bioresour Technol, 2002 Jan, 81(2), 109 - 16
Simulation of a cross-flow shrinking-bed reactor for the hydrolysis of lignocellulosics; Converse AO; An idealized model is developed for the case in which biomass slurry is conveyed through an annulus, with water or steam entering through an inner porous wall and liquid product leaving through an outer porous wall . It is assumed that the ratio of occluded liquid to solid in the slurry is a constant, Rws, and that non-occluded water is immediately removed from the reactor . The goal of > 90% sugar yield with > 10% sugar in the product is almost reached (88% glucose yield, 91% xylose yield, 47 g/l glucose and 45 g/l xylose) at 240 degrees C, 1% acid . Rws = 1 and a radial wash water flow of three times the initial mass flow of solids to the reactor per meter of reactor length per g/l of sugar concentration in the occluded water . If Rws is limited to 3, the yield falls to 85% and the total sugar concentration to 61 g/l . Even without cross-flow wash, the yields can be increased by about 16 percentage points, compared to plug flow, by extracting excess liquid through the outer wall as it is formed . At 200 degrees C, where one might prefer to operate for ease of control and concern about the possibility of making fermentation inhibitors at higher temperatures, the maximum glucose yield in a plug-flow reactor is low (12-13%) whereas in a cross-flow reactor, at a high cross-flow wash rate, it can still be quite high (60-83%) but at a very low concentration (0.57-1.47%) . In these simulations it is assumed that one-half of the inerts is solubilized . The formation of oligomers is neglected.

Int J Syst Evol Microbiol, 2001 Nov, 51(Pt 6), 2171 - 6
Candida bituminiphila, a novel anamorphic species of yeast; Robert V et al.; A novel anamorphic species of yeast belonging to the genus Candida was isolated from tar in Canada . Morphological and physiological observations, as well as phylogenetic analyses, were performed . Conidiophores were produced, were usually short and had sympodial growth, numerous bud scars and a rachis-like structure . They bore one or more conidia . Pseudomycelium was scarcely produced and true mycelium was sparse . No sexual reproduction was observed on corn meal, malt, Gorodkowa, Dextrose Yeast Peptone or V8 agars . Zygoascus hellenicus was physiologically the most closely related species, but it differed from the novel species by its ability to assimilate D-galacturonate and L-rhamnose, ferment sucrose and grow at 37 degrees C . From sequence analysis of the 26S rDNA D1/D2 region, Z . hellenicus and Candida bertae var . bertae were the closest species with 54 and 56 bp substitutions, respectively . Similar results have been obtained from analysis of the 18S rDNA . All these data support the hypothesis that the yeast, named Candida bituminiphila, is a novel species closely related to Z . hellenicus . The holotype and only isolate of C . bituminiphila is strain CBS 8813T (= MUCL 41424T).

Fresenius J Anal Chem, 2001 Oct, 371(4), 541 - 9
Process control of apple winemaking by low-resolution gas-phase Fourier-transform infrared spectroscopy; Ahro M et al.; Four apple wine fermentation processes have been observed by means of direct-inlet gas-phase FTIR spectroscopy . The apple juice concentrates were each fermented by two species of Saccharomyces cerevisiae starters, and the experiment was repeated . The development of the concentrations of 1-propanol, 4-methylpyridine, acetaldehyde, acetic acid, and ethyl acetate was monitored . Two different sampling methods were used--static headspace and direct injection of the must . The performance of the FTIR method is limited by the high ethanol concentration . It can be mathematically proven that the amount of sample can be selected so that any distortion due to ethanol is minimized . Headspace GC-MS was used for preliminary compound identification.

J Environ Sci Health A Tox Hazard Subst Environ Eng, 2001, 36(10), 2027 - 38
Effect of a hydrolytic/acidogenic pre-stage on the organic matter content of wastewater treated in a sequencing batch reactor for biological phosphorous removal; Colmenarejo MF et al.; An increase of 52.7% in acetate concentration was observed when urban wastewater was used to feed a pilot-scale upflow-type, fixed-bed fermentor under a hydraulic retention time of 0.78 h . The fermentor influent and effluent were successively used to feed a laboratory-scale sequencing batch reactor (SBR) using similar operational variables of wastewater volume, sludge purging volume and retention times during the anaerobic and aerobic phase, giving a nominal 4 h hydraulic retention time . The fermentor effluent contained an organic substrate, with a volatile fatty acid content higher than 50mg L(-1), which was appropriate for the growth of the type of microorganisms characteristically found in biological phosphorous removal (BPR) systems, and showed the behaviour of an easily and rapidly biodegradable wastewater . The specific rate of phosphorous release at the anaerobic stage was found to be higher than 0.04mg Pr g VSS(-1) min(-1), when the fermentor effluent is used as feed of the SBR, which demonstrated its favourable conditions for an efficient processing in this type of systems.

Int J Food Microbiol, 2001 Oct 22, 70(1-2), 189 - 95
Acid adaptation and temperature effect on the survival of E . coli O157:H7 in acidic fruit juice and lactic fermented milk product; Hsin-Yi C et al.; In this study, two strains of Escherichia coli O157:H7, (ATCC 43889 and ATCC 43895) were acid adapted at pH 5.0 in tryptic soy broth (TSB) for 4 h . Commercial products of mango juice (pH 3.2), asparagus juice (pH 3.6), Yakult--a diluted milk fermented drink (pH 3.6), and low-fat yoghurt (pH 3.9) were inoculated with acid-adapted or nonadapted cells of E . coli O157:H7 . Survival of the inoculated E . coli O157:H7 in these commercial food products during storage at 25 or 7 degrees C was examined . It was found that although survival of the acid-adapted and nonadapted E . coli O157:H7 ATCC 43895 in asparagus juice during storage at 7 degrees C did not show marked difference, in general, acid adaptation and low temperature enhanced the survival of E . coli O157:H7 in both the commercial fruit juices tested . On the contrary, acid adaptation reduced the survival of both the strains of the test organism in Yakult and low-fat yoghurt stored at 7 degrees C . Besides, E . coli O157:H7 ATCC 43895 survived longer than ATCC 43889 in all the products examined, regardless of the storage temperature and acid adaptation.

Appl Microbiol Biotechnol, 2001 Oct, 57(3), 407 - 11
Study of the production of fructose and ethanol from sucrose media by Saccharomyces cerevisiae; Atiyeh H et al.; The production of ethanol and enriched fructose syrups from a synthetic medium with various sucrose concentrations using the mutant Saccharomyces cerevisiae ATCC 36858 was investigated . In batch tests, fructose yields were above 90% of theoretical values for the sucrose concentrations between 35 g/l and 257 g/l . The specific growth rates and biomass yields were from 0.218 to 0.128 h(-1) and from 0.160 to 0.075 g biomass/g of glucose and fructose consumed, respectively . Ethanol yields were in the range of 72 to 85% of theoretical value when sucrose concentrations were above 81 g/l . The volumetric ethanol productivity was 2.23 g ethanol/(l h) in a medium containing 216 g/l sucrose . Fructo-oligosaccharides and glycerol were also produced in the process . A maximum fructo-oligosaccharides concentration (up to 9 g/l) was attained in the 257 g/l sucrose medium in the first 7 h of the fermentation . These sugars started to be consumed when the concentrations of sucrose in the media were less than 30% of its initial values . The fructo-oligosaccharides mixture was composed of 6-kestose (61.5%), neokestose (29.7%) and 1-kestose (8.8%) . The concentration of glycerol produced in the process was less than 9 g/l . These results will be useful in the production of enriched fructose syrups and ethanol using sucrose-based raw materials.

Appl Microbiol Biotechnol, 2001 Oct, 57(3), 374 - 8
Effect of high-cell-density fermentation of Candida utilis on kinetic parameters and the shift to respiro-fermentative metabolism; Ordaz L et al.; Candida utilis NRRLY-900 was grown in a high-cell-density continuous culture without oxygen limitation . Glucose or molasses was used as carbon source at 30 g l(-1) or 100 g (reducing sugars) l(-1) . At 30 g glucose l(-1), the dilution rate (D) immediately before the change in respiratory metabolism (Dr) was approximately 0.40 h(-1) . At this value of D, the corresponding culture in molasses did not reach the Dr value . When the reducing sugar concentration in the feed was 100 g l(-1), the Dr was 0.15 h(-1) for glucose and 0.3 h(-1) for molasses . When D>Dr, accumulation of ethanol and organic acids occurred, due to physiological changes in C . utilis . The changes observed were a decrease in the biomass yield coefficient per gram of oxygen consumed (YO2) and a sudden increase in the specific oxygen consumption rate (qO2) for each substrate . Therefore, at growth rates above Dr in a high-cell-density culture, C . utilis acquired a flexible catabolism directed towards alternative fermentation routes . The D at which metabolic changes took place seemed to depend on the nature and concentration of the carbon source . Biomass productivity was higher with molasses than with glucose when the fermenter was operated at high D values.

Appl Microbiol Biotechnol, 2001 Oct, 57(3), 368 - 73
Activation of plasma membrane H+-ATPase by ammonium ions in Aspergillus niger; Jernejc K et al.; The addition of ammonium ions to Aspergillus niger cells originally growing on another nitrogen source resulted in rapid medium acidification . The addition of glucose or other fermentable sugars to the mycelium growing on glycerol did not have the same effect . The enzyme responsible for acidification seems to be plasma membrane H+-ATPase, which is most probably triggered by phosphorylation . Using specific activators and inhibitors, we tried to figure out which signalling pathway is involved in the process . No activation of H+-ATPase could be detected in the presence of diacylglycerol and other activators of protein kinase C, indicating that the stimulus is transmitted by another signalling chain . In the presence of inhibitors known to suppress the phosphatidyl-inositol signalling pathway, such as neomycin, compound 48/80 and calmidazolium, no increased H+-ATPase activity could be detected after the addition of ammonium ions . However, some tested inhibitors of the cAMP signalling pathway could not prevent activation of the enzyme by the stimulant . These results support the model in which ammonium-induced activation of proton extrusion in A . niger is mediated via the phosphatidyl-inositol signalling pathway, involving Ca2+/calmoduline-dependent protein kinase but not protein kinase C.

Appl Microbiol Biotechnol, 2001 Oct, 57(3), 309 - 15
Biotransformation of benzaldehyde into (R)-phenylacetylcarbinol by filamentous fungi or their extracts; Rosche B et al.; Extracts of 14 filamentous fungi were examined regarding their potential for production of (R)-phenylacetylcarbinol {(R)-PAC}, which is the chiral precursor in the manufacture of the pharmaceuticals ephedrine and pseudoephedrine . Benzaldehyde and pyruvate were transformed at a scale of 1.2 ml into PAC by cell-free extracts of all selected strains, covering the broad taxonomic spectrum of Ascomycota, Zygomycota and Basidiomycota . Highest final PAC concentrations were obtained with the extracts of Rhizopus javanicus and Fusarium sp . {78-84 mM (11.7-12.6 g/l) PAC within 20 h from initial substrate concentrations of 100 mM benzaldehyde and 150 mM pyruvate} . (R)-PAC was in about 90-93% enantiomeric excess . Rhizopus javanicus had the advantage of faster growth than Fusarium sp . Rhizopus javanicus mycelia were used as an example in a biotransformation process based on whole cells and benzaldehyde and glucose as substrates . The substrate pyruvate was generated through the fungal fermentation of glucose . Only 19 mM PAC (2.9 g/l) were produced within 8 h from 80 mM benzaldehyde . with evidence of significant benzyl alcohol production.

Biosci Biotechnol Biochem, 2001 Oct, 65(10), 2361 - 3
Appearance of poor-fermenting variants in brewing yeast culture; Yamagishi H et al.; A class of yeast variants appears after cultivation of a bottom-fermenting brewing yeast strain, IFO2003 . Although IFO2003 fails to grow well above 33 degrees C, the variants can grow up to 34 degrees C . Temperature-resistance and an acquired phenotype of maltose poor-fermentation ability are strictly correlated in the bottom-fermenting brewing yeast, enabling us to develop easy estimation of the fermentation ability of the variants.

Biosci Biotechnol Biochem, 2001 Oct, 65(10), 2294 - 6
Anti-stress and anti-fatigue effects of fermented rice bran; Kim KM et al.; The anti-stress and anti-fatigue effects on rats and mice of a hot water extract of rice bran fermented with Saccharomyces cerevisae IFO 2346 were investigated . Oral administration (1 g/kg/day) of the hot water extract of fermented rice bran (FRB) inhibited major changes in the weight of the adrenal, thymus, spleen and thyroid, showing an anti-stress effect . The hot water extract of FRB also inhibited increases in the GPT and LDH activity, cholesterol and glucose in the serum . The administration (1 g/kg/day) for 2 weeks significantly prolonged the swimming time, resulting in an increase in the anti-fatigue effect . It is considered from these results that FRB had anti-stress and anti-fatigue effects.

Am J Clin Nutr, 2002 Jan, 75(1), 104 - 11
Effects of high-resistant-starch banana flour (RS(2)) on in vitro fermentation and the small-bowel excretion of energy, nutrients, and sterols: an ileostomy study; Langkilde AM et al.; BACKGROUND: Resistant starch (RS) has attracted interest because of its effects in the colon and implications for health . Knowledge of how RS influences small-intestinal absorption of nutrients, sterol metabolism, and colonic fermentation is sparse . OBJECTIVES: The objectives of this study were to measure the effect of RS(2), a type of RS in banana flour, on the ileal excretion of energy, nutrients, and sterols, and to compare in vivo measurement of RS in the ileostomy model with previously published intubation data . In addition, we sought to estimate a fermentation pattern by using ileal effluents for in vitro fermentation . DESIGN: The present study was divided into 2 parts . Study A involved 10 ileostomy subjects who were given a controlled diet with the addition of 30 g raw green banana flour (RBF)/d, which contains RS(2), or cooked green banana flour (CBF)/d in random order . Study B involved 7 ileostomy subjects who were given a plant-polysaccharide-free diet with the addition of 30 g RBF/d . RESULTS: In study A, the dry weight of the ileostomy effluents and the ileal excretion of energy, iron, and chenodeoxycholic acid, but not total sterols, were higher after the addition of RBF than of CBF to the diet . In vitro fermentation of the ileal effluents obtained after the addition of RBF to the diet showed higher concentrations of acetate and butyrate . In study B, the ileal excretion of starch was lower than the amount calculated from earlier studies by use of the intubation technique . CONCLUSIONS: The addition of RBF containing RS(2) to the diet of ileostomy subjects did not interfere with small-bowel absorption of nutrients or total sterols, except for a small increase in iron excretion . The ileostomy model seems to give reliable results for in vivo measurement of RS.

J Biotechnol, 2002 Feb 28, 93(3), 253 - 68
Fluidized bed adsorption of cephalosporin C; Hicketier M et al.; Fluidized bed adsorption can substantially simplify the recovery of products from fermentation . There are, however, several critical parameters, which have a significant influence on the performance of such systems . This paper presents experimental results on the adsorption of an antibiotic, Cephalosporin C, on macroporous adsorbents of the polystyrene type and on an ion exchanger . Internals (static mixers) were used to control bed expansion and mixing, the range of flow rates could thus be extended significantly . An integrated mathematical model was developed comprising bed expansion, residence time distribution and mixing, adsorption kinetics and equilibria.

J Biotechnol, 2002 Feb 28, 93(3), 243 - 51
Scale-up of dialysis fermentation for high cell density cultivation of Escherichia coli; Fuchs C et al.; In dialysis fermentations inhibiting metabolites can be removed from cell suspensions resulting in a prolonged exponential growth phase and higher production yields . Because of successful high cell density cultivations of Escherichia coli in a laboratory dialysis reactor, a scale-up of the process was investigated . To provide sufficient membrane area for dialysis in a technical scale fermenter, an external membrane module was used, that was also applied for oxygen supply to the culture in the external loop . Cultivations with recombinant E . coli K12, with and without induction, in 2- and 300-l reactors were carried out using external modules . Cell densities exceeding 190 g l(-1), previously obtained in laboratory dialysis fermentation, were also produced with external dialysis modules . Protein concentration in a 300-l reactor was increased to the 3.8-fold of industrial fed-batch-fermentations.

J Biotechnol, 2002 Feb 28, 93(3), 217 - 29
Flow cytometry as a useful tool for process development: rapid evaluation of expression systems; Patkar A et al.; Flow cytometry is an established tool in fundamental studies of single-cell microbial physiology . Here we show that it can also provide valuable information for process development . Using recombinant Escherichia coli strains, which express the protein-based polymer (GVGIP)(260)GVGVP, the utility of flow cytometry in monitoring and optimization of fermentations is demonstrated . Single cell right angle light scatter was found to be significantly affected by intracellular product formation possibly due to the formation of inclusion bodies . Translational fusions with green fluorescent protein (GFP) enabled monitoring of product accumulation, as well as plasmid free cell fraction (PFCF) . Such fusions also allowed rapid evaluation of induction strategies and three different expression systems based on the T7 promoter, T7-lac promoter and the P(BAD) promoter . The expression system based on the P(BAD) promoter was found to be superior to the T7-based system.

Rapid Commun Mass Spectrom, 2002, 16(1), 69 - 76
Kinetics and isotope patterns of ethanol and acetaldehyde emissions from yeast fermentations of glucose and glucose-6,6-d2 using selected ion flow tube mass spectrometry: a case study; Smith D et al.; As a prelude to investigations of the emission of metabolites from human cell lines in vitro, we have conducted a study using selected ion flow tube mass spectrometry (SIFT-MS) of the acetaldehyde and ethanol that appear in the headspace above a fermenting yeast/glucose/water mixture in sealed glass bottles at a temperature of 30 degrees C . A fixed quantity of yeast (10 mg) and varying amounts (2, 4, 8 and 16 mg) of both non-deuterated glucose and glucose-6,6-d2 in 5 mL of water were used and the emission of the acetaldehyde and the ethanol were observed as a function of time . The ethanol and acetaldehyde concentrations in the headspace were obtained from the magnitudes of their characteristic ions on the accumulated SIFT mass spectra and, when the deuterated glucose was used, characteristic singly and doubly deuterated ions were obvious . This study indicates, as expected, that ethanol is the major species generated and that acetaldehyde is a relatively minor component of the headspace and a very minor component of the liquid phase . We estimate that about 10(8) ethanol molecules are produced per minute per cell in this yeast fermentation process . The distribution of the non-deuterated and partially deuterated ethanol under these fermentation conditions is observed to be C2H5OH (66 +/- 4)%, C2H4DOH(6 +/- 1)%, C2H3D2OH(28 +/- 4)%, and the analogous distribution for the acetaldehyde is the same, within error . These results indicate that the D atoms in the glucose-6,6-d2 are mostly retained by the 6-C atom, but the appearance of the singly deuterated ethanol and acetaldehyde indicates that some D/H mixing must be occurring in the enzymatic reactions . The results of this study illustrate the potential and power of on-line SIFT-MS analysis in this area of research .

Biotechnol Bioeng, 2002 Feb 5, 77(3), 324 - 8
Formate accumulation due to DNA release in aerobic cultivations of Escherichia coli; Castan A et al.; Three different aerobic fed-batch processes of Escherichia coli were studied, two for the production of a recombinant protein and one process with a wild-type E . coli strain . In all three processes, an accumulation of formate could be observed in the latter part of the process . Analysis of the concentration of DNA in the medium revealed that the release of DNA coincided with the accumulation of formate . It was found that increasing concentrations of DNA correlated in almost linearly increasing concentrations of formate . Formate accumulation is caused by mixed acid fermentation, although no oxygen limitation was measured with the DO electrode . It is proposed that extracellular DNA restrained mass transfer between the bulk medium and the cell . To investigate if the DNA accumulation caused formate production, DNA was removed by continuous feeding of a DNA binding polymer to the medium . The addition of the polymer decreased the content of free DNA in the broth and the formate was reassimilated . Furthermore, additional DNA early in the process resulted in early formate accumulation .

Biotechnol Bioeng, 2002 Jan 20, 77(2), 186 - 93
Aerobic glucose metabolism of Saccharomyces kluyveri: growth, metabolite production, and quantification of metabolic fluxes; Moller K et al.; The growth and product formation of Saccharomyces kluyveri was characterized in aerobic batch cultivation on glucose . At these conditions it was found that ethyl acetate was a major overflow metabolite in S . kluyveri . During the exponential-growth phase on glucose ethyl acetate was produced at a constant specific rate of 0.12 g ethyl acetate per g dry weight per hour . The aerobic glucose metabolism in S . kluyveri was found to be less fermentative than in S . cerevisiae, as illustrated by the comparably low yield of ethanol on glucose (0.08 +/- 0.02 g/g), and high yield of biomass on glucose (0.29 +/- 0.01 g/g) . The glucose metabolism of S . kluyveri was further characterized by the new and powerful techniques of metabolic network analysis . Flux distributions in the central carbon metabolism were estimated for respiro-fermentative growth in aerobic batch cultivation on glucose and respiratory growth in aerobic glucose-limited continuous cultivation . It was found that in S . kluyveri the flux into the pentose phosphate pathway was 18.8 mmole per 100 mmole glucose consumed during respiratory growth in aerobic glucose-limited continuous cultivation . Such a low flux into the pentose phosphate pathway cannot provide the cell with enough NADPH for biomass formation which is why the remaining NADPH will have to be provided by another pathway . During batch cultivation of S . kluyveri the tricarboxylic acid cycle was working as a cycle with a considerable flux, that is in sharp contrast to what has previously been observed in S . cerevisiae at the same growth conditions, where the tricarboxylic acid cycle operates as two branches . This indicates that the respiratory system was not significantly repressed in S . kluyveri during batch cultivation on glucose .

Biotechnol Bioeng, 2002 Jan 20, 77(2), 148 - 54
Host selection as a downstream strategy: polyelectrolyte precipitation of beta-glucuronidase from plant extracts; Menkhaus TJ et al.; Host selection can be a strategy to simplify downstream processing for protein recovery . Advancing capabilities for using plants as hosts offers new host opportunities that have received only limited attention from a downstream processing perspective . Here, we investigated the potential of using a polycationic precipitating agent (polyethylenimine; PEI) to precipitate an acidic model protein (beta-glucuronidase; GUS) from aqueous plant extracts . To assess the potential of host selection to enhance the ease of recovery, the same procedure was applied to oilseed extracts of canola, corn (germ), and soy . For comparison, PEI precipitation of GUS was also evaluated from a crude bacterial fermentation broth . Two versions of the target protein were investigated--the wild-type enzyme (WTGUS) and a genetically engineered version containing 10 additional aspartates on each of the enzyme's four homologous subunits (GUSD10) . It was found that canola was the most compatible expression host for use with this purification technique . GUS was completely precipitated from canola with the lowest dosage of PEI (30 mg PEI/g total protein), and over 80% of the initial WTGUS activity was recovered with 18-fold purification . Precipitation from soy gave yields over 90% for WTGUS but only 1.3-fold enrichment . Corn, although requiring the most PEI relative to total protein to precipitate (210 mg PEI/g total protein for 100% precipitation), gave intermediate results, with 81% recovery of WTGUS activity and a purification factor of 2.6 . The addition of aspartate residues to the target protein did not enhance the selectivity of PEI precipitation in any of the systems tested . In fact, the additional charge reduced the ability to recover GUSD10 from the precipitate, resulting in lower yields and enrichment ratios compared to WTGUS . Compared to the bacterial host, plant systems provided lower polymer dosage requirements, higher yields of recoverable activity and greater purification factors .

Rheumatology (Oxford), 2001 Dec, 40(12), 1355 - 8
The prevalence of Mycoplasma fermentans in patients with inflammatory arthritides; Gilroy CB et al.; OBJECTIVES: To search for evidence that Mycoplasma fermentans is involved in the pathogenesis of some forms of human arthritis by testing for the presence of mycoplasmal DNA in joint material . METHODS: M . fermentans DNA was detected by the identification of a 104-base pair amplification product of the polymerase chain reaction (PCR) . RESULTS: M . fermentans DNA was detected in synovial fluid samples from six (17%) of 35 patients with rheumatoid arthritis (RA) and 18 (21%) of 85 patients with seronegative arthritis . These detection rates were significantly greater than in samples from patients with osteoarthritis or crystal synovitis, none of 26 of these being positive . CONCLUSIONS: M . fermentans could be involved in the pathogenesis of some forms of inflammatory arthritis and this possibility is worthy of further study.

FEMS Microbiol Lett, 2001 Dec 18, 205(2), 385 - 9
Suspension cultivation of Mycobacterium ulcerans for the production of mycolactones; Cadapan LD et al.; Mycolactones are polyketide toxins produced by Mycobacterium ulcerans, the causative agent of the tropical skin disease known as Buruli ulcer . Development of novel therapeutic agents from mycolactones has been hindered by the difficulty of producing sufficient amounts of material . Here, we describe the successful adaptation of M . ulcerans to suspension cultivation and the development of a fed-batch fermentation process that was scaled up to 150 l . In addition to producing mycolactones A and B, a number of new mycolactone-related compounds were also observed.

FEMS Microbiol Lett, 2001 Dec 18, 205(2), 231 - 6
Vacuolar H+-ATPase, but not mitochondrial F1F0-ATPase, is required for aluminum resistance in Saccharomyces cerevisiae; Hamilton CA et al.; It was recently shown that vacuolar ATPase and mitochondrial F1F0-ATPase activities are induced by aluminum (Al) in an Al-resistant cultivar of wheat, suggesting that induction of these enzymes could be an adaptive trait involved in Al resistance . To test this hypothesis, we used the Saccharomyces cerevisiae model system . In yeast, unlike wheat, the activity, transcript and protein levels of mitochondrial F1F0-ATPase, but not vacuolar ATPase, are induced by Al, while plasma membrane P-ATPase activity is inhibited . However, yeast vacuolar ATPase mutant strains are hypersensitive to Al, while F1F0-ATPase mutant strains exhibit wild-type growth . These data suggest that vacuolar ATPase activity is involved in Al resistance, with ATP required for this activity supplied by mitochondrial F1F0-ATPase or fermentation.

FEMS Microbiol Lett, 2001 Dec 18, 205(2), 209 - 14
Interspecies H2 transfer in cellulose degradation between fibrolytic bacteria and H2-utilizing microorganisms from the human colon; Robert C et al.; Interspecies H2 transfer between two newly isolated fibrolytic strains (18P13 and 18P16) and H2-utilizing methanogen or acetogen from the human colon was investigated during in vitro cellulose degradation . Both H2-consuming microorganisms utilized efficiently H2 produced from cellulose fermentation by the fibrolytic species . H2 utilization by Methanobrevibacter smithii did not change the metabolism and the cellulolytic activity of strain 18P16 whereas it induced a metabolic shift in strain 18P13 . However, this metabolic shift was not associated with enhancement of cellulose degradation . In contrast, an increase in cellulose breakdown was observed when strain 18P13 was cultivated with Ruminococcus hydrogenotrophicus . This stimulating effect could be attributed to both the autotrophic and the heterotrophic metabolism of the acetogen in the coculture.

Br J Nutr, 2001 Dec, 86(6), 717 - 24
Influence of nitrogen source on the fermentation of fibre from barley straw and sugarbeet pulp by ruminal micro-organisms in vitro; Ranilla MJ et al.; Incubations were carried out with a batch culture system to study the effects of different N sources on the fermentation by ruminal micro-organisms from Merino sheep of two fibre substrates derived from feedstuffs that differed in their fermentation rate . The substrates were neutral-detergent fibre (NDF) from barley straw and sugarbeet pulp . N sources were ammonia (NH4Cl) and peptides (Trypticase) . Three treatments were made by replacing ammonia-N with peptide-N at levels of 0 (AMMO), 33 (PEPLOW) and 66 % (PEPHIGH) of total N . There were no differences (P>0.05) between treatments in NDF degradation for both the barley straw and the sugarbeet pulp . Peptides increased (P<0.05) total volatile fatty acids daily production for both substrates, with greater values (P<0.001) for PEPHIGH than for PEPLOW for the sugarbeet pulp . The presence of peptides also increased (P<0.05) microbial N synthesis compared with AMMO, with PEPHIGH supporting more growth (P<0.001) than PEPLOW when the sugarbeet pulp NDF was fermented . The presence of peptides increased (P<0.01) the amount of solids-associated micro-organisms (SAM)-N for both the barley straw and the sugarbeet pulp fibres, values in the PEPHIGH treatment being higher (P<0.001) than those in PEPLOW . The proportion of SAM-N in the total microbial N was not affected (P>0.05) by the presence of peptides compared with the AMMO treatment, but values were greater for the PEPHIGH compared with the PEPLOW N source, reaching statistical significance (P<0.05) only for the sugarbeet pulp . For liquid-associated micro-organisms, the AMMO treatment resulted in the greatest (P<0.05) proportion of N derived from ammonia for both substrates, with a further decrease (P<0.01) for the PEPHIGH treatment compared with the PEPLOW for the sugarbeet pulp, indicating preferential uptake of peptides when they were available . Microbial growth efficiency (g microbial N/kg NDF degraded) was not affected (P>0.05) by N source . These results indicate that N forms other than ammonia are needed for maximal growth of fibre-digesting ruminal micro-organisms.

J Org Chem, 2001 Dec 28, 66(26), 8717 - 21
Nomofungin: a new microfilament disrupting agent; Ratnayake AS et al.; A new alkaloid, nomofungin, has been isolated from the fermentation broth of an unidentified endophytic fungus obtained from the bark of Ficus microcarpa L . The structure of nomofungin was determined by application of spectroscopic methods . The absolute stereochemistry of nomofungin was assigned by using the exciton chirality method . Nomofungin disrupts microfilaments in cultured mammalian cells and is moderately cytotoxic with minimum inhibitory concentrations (MICs) of 2 and 4.5 microg/mL against LoVo and KB cells, respectively . The ring system of nomofungin is unprecedented.

Yeast, 2001 Dec, 18(16), 1515 - 24
Functional analysis of the hexose transporter homologue HXT5 in Saccharomyces cerevisiae; Diderich JA et al.; The HXT5 gene encodes a functional hexose transporter that has moderate affinity for glucose (K(m)=10 mM), moderate to low affinity for fructose (K(m)=40 mM) and low affinity for mannose (K(m)>100 mM) . The sole presence of Hxt5p in an otherwise hexose transport null mutant is sufficient to sustain a flux through glycolysis from glucose to fermentative products . However, the presence of HXT5 as the sole hexose transporter gene results in extremely poor growth on glucose, which suggests the involvement of glucose repression in the transcriptional regulation of HXT5 . From Northern blot analysis on the members of the HXT family and studies with HXT5 tagged with the green fluorescent protein (GFP), it is evident that HXT5 is transcribed and translated during conditions of relatively slow growth, during growth on non-fermentable carbon sources and in particular during sporulation . In wild-type batch cultivations on fermentable carbon sources, Hxt5p is abundant in stationary phase or after depletion of the fermentable carbon source, which seems independent of the carbon source . The deletion of HXT5 does not result in a clear phenotype . A shift of stationary phase cells to fresh glucose medium resulted in somewhat slower resumption of growth in the hxt5 deletion strain compared to the wild-type strain . The abundance of Hxt5p during stationary phase, sporulation and low glucose conditions suggests that HXT5 is a 'reserve' transporter, which might be involved in the initial uptake of glucose after the appearance of glucose . Other possible functions of the protein encoded by HXT5 will be discussed in the context of the results .

Oncol Rep, 2002 Jan-Feb, 9(1), 69 - 73
Prevention by long-term fermented miso of induction of colonic aberrant crypt foci by azoxymethane in F344 rats; Ohara M et al.; The present study was designed to investigate the effects of fermented miso in the diet on the induction of aberrant crypt foci (ACF) by azoxymethane (AOM) in male F344 rats . A total of 50 rats, 8 weeks of age, were divided into 5 groups and given weekly subcutaneous injections of AOM (15 mg/kg body wt) for 3 weeks . Rats were fed a normal control MF solid diet, or solid diet containing 10% long-term fermented (aged), medium- or short-term fermented miso, or 2.2% NaCl for 5 weeks, starting one week before the first AOM dosing . It was found that, compared to the control (MF) diet, the long-term fermented diet significantly decreased (by 22.2%) ACF/colon, but increased (by 18.2%) the number of aberrant crypts (Acs)/focus . The latter was also increased by the medium-term fermented diet (by 25.3%) . The PCNA labeling index was only affected by the short-term fermented diet (36.9% increase) and by 2.2% NaCl diet (27.2% increased) . The present results indicate that aged or completely fermented miso supplemented into the diet, could act as a chemopreventive agent for colon carcinogenesis.

J Mass Spectrom, 2001 Oct, 36(10), 1108 - 15
Sequencing of new beauverolides by high-performance liquid chromatography and mass spectrometry; Kuzma M et al.; Mass spectrometry (MS) and tandem mass spectrometry (MS(n)) were used for the identification of beauverolides in the fermentation broth of Beauveria bassiana and for evaluation of the purified fraction obtained by sublimation of beauverolides . Besides being a new efficient route for purification of beauverolides, sublimation provided an enrichment of new minor lipophilic beauverolides of lower molecular weight from the original complex mycelial extract . The product ion collision-induced dissociation (CID) spectra obtained on an ion trap (electrospray ionization), the in-source CID mass spectra on a sector instrument (atmospheric-pressure chemical ionization) and the post-source decay matrix-assisted laser desorption/ionization mass spectra of beauverolides were compared and evaluated . All MS(n) experiments started with singly charged precursor ions . The following two new representatives of this group of compounds were identified by high-performance liquid chromatography and MS (HPLC/MS): cyclo-(3-hydroxy-4-methyloctanoyl-valyl-alanyl-leucyl) and cyclo-(3-hydroxy-4-methyloctanoyl-tyrosyl-alanyl-leucyl) . Individual structures were confirmed by preparative isolation and nuclear magnetic resonance spectroscopy . The structure of a third novel and minor beauverolide was tentatively assigned by HPLC/MS only as cyclo-(3-hydroxy-4-methyldecanoyl-valyl-alanyl-Lxx), Lxx = leucyl, isoleucyl, or allo-isoleucyl .

Biotechnol Bioeng, 2002 Jan 5, 77(1), 49 - 60
Kinetic model for nitrogen-limited wine fermentations; Cramer AC et al.; A physical and mathematical model for wine fermentation kinetics has been developed to predict sugar utilization curves based on experimental data from wine fermentations with various initial nitrogen and sugar concentrations in the juice . The model is based on: (1) yeast cell growth limited by nitrogen; (2) sugar utilization rates and ethanol production rates proportional solely to the number of viable cells; and (3) a death rate for cells proportional to alcohol content . All but one parameter in the model can be estimated from existing data . However, experiments to find this final parameter, a constant describing cell death, indicate that cell death may not be the critical factor in determining fermentation kinetics as cell viability remains significant until sugar utilization has ceased . The model, nevertheless, predicts a transition from normal to sluggish to stuck fermentations as initial nitrogen levels decrease . It also predicts that fermentations with high initial Brix levels may go to completion when supplemented with nitrogen in the form of ammonia . Therefore, we hypothesize that the model is valid but that ethanol causes the yeast cells to become inactive while remaining viable . Experimental verification of the model has been performed using flask-scale experiments . The model has also been used to evaluate the possibility of using nitrogen or viable cell additions to avoid or correct problem (i.e., sluggish or stuck) fermentations .

Biotechnol Bioeng, 2001 Dec, 76(4), 376 - 90
Microbial synthesis of p-hydroxybenzoic acid from glucose; Barker JL et al.; A series of recombinant Escherichia coli strains have been constructed and evaluated for their ability to synthesize p-hydroxybenzoic acid from glucose under fed-batch fermentor conditions . The maximum concentration of p-hydroxybenzoic acid synthesized was 12 g/L and corresponded to a yield of 13% (mol/mol) . Synthesis of p-hydroxybenzoic acid began with direction of increased carbon flow into the common pathway of aromatic amino acid biosynthesis . This was accomplished in all constructs with overexpression of a feedback-insensitive isozyme of 3-deoxy-D-arabino-heptulosonic acid 7-phosphate synthase . Expression levels of enzymes in the common pathway of aromatic amino acid biosynthesis were also increased in all constructs to deliver increased carbon flow from the beginning to the end of the common pathway . A previously unreported inhibition of 3-dehydroquinate synthase by L-tyrosine was discovered to be a significant impediment to the flow of carbon through the common pathway . Chorismic acid, the last metabolite of the common pathway, was converted into p-hydroxybenzoic acid by ubiC-encoded chorismate lyase . Constructs differed in the strategy used for overexpression of chorismate lyase and also differed as to whether mutations were present in the host E . coli to inactivate other chorismate-utilizing enzymes . Use of overexpressed chorismate lyase to increase the rate of chorismic acid aromatization was mitigated by attendant decreases in the specific activity of DAHP synthase and feedback inhibition caused by p-hydroxybenzoic acid . The toxicity of p-hydroxybenzoic acid towards E . coli metabolism and growth was also evaluated .

Biotechnol Bioeng, 2001 Dec 20, 75(6), 733 - 40
Scaleable downstream recovery of nematodes used as biopesticides; Wilson JA et al.; This study assesses the suitability of sieving as a scaleable technique for the separation of adult nematodes from infective juveniles, the latter is an effective bioinsecticide whereas the former is waste material resulting from the fermentation process . Batch and semibatch experiments using conventional flow-assisted wet sieving and a novel cross-flow sieving technique were used to study the separation of juveniles from adult nematodes . The experiments were carried out using small-scale devices and the data were analyzed in terms of the screen effectiveness factor . The results were used to identify the sieve size and operating conditions for optimum juvenile recovery . It was found that, for a given species of nematode, optimum recovery was achieved when sieving was carried out in the cross-flow mode, the maximum recovery being a function of the size of the screen . Industrial-scale self-cleaning equipment capable of large-scale continuous screening was used to confirm the capacity of the small-scale operation for scale-up . Experimental results with this unit showed that in continuous operation sieving time is an additional parameter that influences separation performance .

Biotechnol Bioeng, 2001 Dec 20, 75(6), 718 - 24
Recombinant enterokinase light chain with affinity tag: expression from Saccharomyces cerevisiae and its utilities in fusion protein technology; Choi SI et al.; Enterokinase and recombinant enterokinase light chain (rEK(L)) have been used widely to cleave fusion proteins with the target sequence of (Asp)(4)-Lys . In this work, we show that their utility as a site-specific cleavage agent is compromised by sporadic cleavage at other sites, albeit at low levels . Further degradation of the fusion protein in cleavage reaction is due to an intrinsic broad specificity of the enzyme rather than to the presence of contaminating proteases . To offer facilitated purification from fermentation broth and efficient removal of rEK(L) after cleavage reaction, thus minimizing unwanted cleavage of target protein, histidine affinity tag was introduced into rEK(L) . Utilizing the secretion enhancer peptide derived from the human interleukin 1 beta, the recombinant EK(L) was expressed in Saccharomyces cerevisiae and efficiently secreted into culture medium . The C-terminal His-tagged EK(L) was purified in a single-step procedure on nickel affinity chromatography . It retained full enzymatic activity similar to that of EK(L), whereas the N-terminal His-tagged EK(L) was neither efficiently purified nor had any enzymatic activity . After cleavage reaction of fusion protein, the C-terminal His-tagged EK(L) was efficiently removed from the reaction mixture by a single passage through nickel-NTA spin column . The simple affinity tag renders rEK(L) extremely useful for purification, post-cleavage removal, recovery, and recycling and will broaden the utility and the versatility of the enterokinase for the production of recombinant proteins .

Biotechnol Bioeng, 2001 Dec 20, 75(6), 702 - 9
Viability, strength, and fragmentation of Saccharopolyspora erythraea in submerged fermentation; Stocks SM et al.; Two fermentations of the commercially important erythromycin-producing filamentous bacterium Saccharopolyspora erythraea were conducted in defined media . One was glucose-limited and the other nitrate-limited . The viability of the hyphae was determined using the fluorescent stain BacLight (Molecular Probes, Eugene, OR) . Also, the force required to strain hyphae to breakage was determined using micromanipulation and a sensitive force transducer . In both fermentations, fragmentation coincided with the appearance of regions in the mycelia with permeabilised membranes (considered nonviable) . Under glucose-limitation, hyphal breaking force rose to 1,050 +/- 130 nN at the end of the growth phase and fell to an undetectable value as a result of glucose exhaustion . Under nitrate-limitation, hyphal breaking force fell from 900 +/- 160 nN during the growth phase to 550 +/- 40 nN in the stationary phase . In both cases image analysis showed that the dimensions of mycelia were of the same order, suggesting that the major factor influencing fragmentation was the appearance of nonviable regions (assumed to be weak) . The location in which nonviable regions first appear within hyphae could not be determined because of their appearance coinciding with fragmentation .

Biotechnol Bioeng, 2001 Dec 20, 75(6), 666 - 75
Discrete particle simulations predicting mixing behavior of solid substrate particles in a rotating drum fermenter; Schutyser MA et al.; A soft-sphere discrete particle model was used to simulate mixing behavior of solid substrate particles in a slow rotating drum for solid-state fermentation . In this approach, forces acting on and subsequent motion of individual particles can be predicted . The (2D) simulations were qualitatively and quantitatively validated by mixing experiments using video and image analysis techniques . It was found that the simulations successfully predicted the mixing progress as a function of the degree of filling and size of the drum . It is shown that only relatively large, straight baffles perpendicular to the drum wall (67% of the drum radius) increase the mixing performance of the rotating drum . Considering the different aspects of mixing dealt with in this work, it is concluded that the soft sphere discrete particle model can serve as a valuable tool for investigating mixing of solid substrate particles . Finally, it is expected that this model may evolve into a potential tool for design and scale-up of mixed solid-state fermenters .

Biotechnol Bioeng, 2001 Dec 5, 75(5), 540 - 9
Effects of furfural on anaerobic continuous cultivation of Saccharomyces cerevisiae; Horvath IS et al.; Furfural is an important inhibitor of yeast metabolism in lignocellulose-derived substrates . The effect of furfural on the physiology of Saccharomyces cerevisiae CBS 8066 was investigated using anaerobic continuous cultivations . Experiments were performed with furfural in the feed medium (up to 8.3 g/L) using three different dilution rates (0.095, 0.190, and 0.315 h(-1)) . The measured concentration of furfural was low (< 0.1 g/L) at all steady states obtained . However, it was not possible to achieve a steady state at a specific conversion rate of furfural, q(f), higher than approximately 0.15 g/g.h . An increased furfural concentration in the feed caused a decrease in the steady-state glycerol yield . This agreed well with the decreased need for glycerol production as a way to regenerate NAD+, i.e., to function as a redox sink because furfural was reduced to furfuryl alcohol . Transient experiments were also performed by pulse addition of furfural directly into the fermentor . In contrast to the situation at steady-state conditions, both glycerol and furfuryl alcohol yields increased after pulse addition of furfural to the culture . Furthermore, the maximum specific conversion rate of furfural (0.6 g/g.h) in dynamic experiments was significantly higher than what was attainable in the chemostat experiments . The dynamic furfural conversion could be described by the use of a simple Michaelis-Menten-type kinetic model . Also furfural conversion under steady-state conditions could be explained by a Michaelis-Menten-type kinetic model, but with a higher affinity and a lower maximum conversion rate . This indicated the presence of an additional component with a higher affinity, but lower maximum capacity, either in the transport system or in the conversion system of furfural .

J Agric Food Chem, 2001 Dec, 49(12), 5822 - 7
Characterization of peptides formed during fermentation of cocoa bean; Buyukpamukcu E et al.; Analysis by SDS-PAGE and GPC-MS of fermented cocoa extracts shows changes in the amount and composition of the major proteins, accompanied by formation of complex distributions of peptides . MS/MS studies and application of SEQUEST sequencing software have allowed identification of two related peptides, a hexapeptide and a nonapeptide, formed from vicilin, one of the cocoa storage proteins . Time course studies of the two peptides show different abundance profiles and indicate, in part, production of the hexapeptide from the nonapeptide.

J Agric Food Chem, 2001 Dec, 49(12), 5809 - 16
Effect of different winemaking technologies on phenolic composition in Tinta Miúda red wines; Sun B et al.; The influence of different types of winemaking technology on the contents of catechins, proanthocyanidins, and anthocyanins in Tinta Miuda red wines was studied . The Tinta Miuda red wines were made by fermentation with carbonic maceration, fermentation with stem contact, and fermentation without stem contact, respectively . The analysis of individual catechins, procyanidins, and anthocyanins in these wines was performed by HPLC, and quantification of total catechins, total oligomeric proanthocyanidins, total polymeric proanthocyanidins, and total anthocyanins was carried out by spectrophotometric methods . The wine made by carbonic maceration contained the highest amounts of both catechins and oligomeric and polymeric proanthocyanidins, followed by the wine made by fermentation with stem contact, whereas the wine made by fermentation without stem contact contained the lowest of these compounds . On the other hand, the concentrations of total anthocyanins and nearly all individual anthocyanins in the carbonic maceration wine were lower than those in the wines made by fermentation with stem contact and fermentation without stem contact . These results indicated that, although the carbonic maceration technique could retain higher amounts of catechins and proanthocyanidins in wine, it did not favor retaining or stabilizing anthocyanins in wine.

J Agric Food Chem, 2001 Dec, 49(12), 5797 - 808
Extraction of phenolics and changes in antioxidant activity of red wines during vinification; Burns J et al.; The moderate consumption of alcoholic beverages has been associated with protection against the development of coronary heart disease . Although alcohol itself can help prevent coronary heart disease through a number of mechanisms, red wine appears to offer protection above and beyond that attributable to alcohol alone . Red wine is a complex fluid containing grape, yeast, and wood-derived phenolic compounds, the majority of which have been recognized as potent antioxidants . The aim of this study was to investigate the major phenolic contributors to the antioxidant activity of wine . To this end, four wines were followed during the first 7-9 days of vinification . Individual phenolic compounds were quantified by HPLC, and antioxidant activity was determined by electron spin resonance spectroscopy . The extraction of the phenolics was found to be influenced by vinification procedure, grape quality, and grape variety . Although fermenting wines reached a total phenolic content comparable to that of a bottled wine after 9 days of vinification, the antioxidant activity was significantly lower than that of a finished wine . This suggests that the larger polyphenolic complexes and condensation products that appear during aging make a sizable contribution to the overall antioxidant activity of red wines.

J Bacteriol, 2002 Jan, 184(1), 302 - 6
Utilization of L-ascorbate by Escherichia coli K-12: assignments of functions to products of the yjf-sga and yia-sgb operons; Yew WS et al.; Escherichia coli K-12 can ferment L-ascorbate . The operon encoding catabolic enzymes in the utilization of L-ascorbate (ula) has been identified; this operon of previously unknown function had been designated the yif-sga operon . Three enzymes in the pathway that produce D-xylulose 5-phosphate have been functionally characterized: 3-keto-L-gulonate 6-phosphate decarboxylase (UlaD), L-xylulose 5-phosphate 3-epimerase (UlaE), and L-ribulose 5-phosphate 4-epimerase (UlaF) . Several products of the yia-sgb operon were also functionally characterized, although the substrate and physiological function of the operon remain unknown: 2,3-diketo-L-gulonate reductase (YiaK), 3-keto-L-gulonate kinase (LyxK), 3-keto-L-gulonate 6-phosphate decarboxylase (SgbH), and L-ribulose 5-phosphate 4-epimerase (SgbE).

J Biochem Biophys Methods, 2002 Jan 4, 50(2-3), 99 - 109
Using spectrophotometry and spectral mapping technique for the study of the production of manganese-dependent and manganese-independent peroxidases by Pleurotus ostreatus; Morais H et al.; The activity of manganese-dependent and manganese-independent peroxidases produced by Pleurotus ostreatus in culture media composed of agro-residues was measured by visible spectrophotometry . The overall enzyme activity and its selectivity were separated by using spectral mapping technique followed by nonlinear mapping . The relationships between the parameters of enzyme production and the composition of culture media and fermentation time was assessed by stepwise regression analysis . Calculations proved that the addition of extract of straw to the culture media significantly decreased the overall production of both enzymes, whereas the selectivity of enzyme production was influenced by amount of potato extract and the concentration of total sugar in the culture media . Enzyme activity depended quadratically on the fermentation time.

Biochem Biophys Res Commun, 2001 Dec 21, 289(5), 1282 - 6
Molecular cloning of novel mouse and human putative citrate lyase beta-subunit; Morikawa J et al.; Using a fluorescent differential display (FDD) technique, a novel cDNA was identified by screening for gene expressed differentially between the Dunn osteosarcoma cell line and the LM8 cell line, an isolated variant of the Dunn cell line that has high metastatic potential to the lung . Molecular cloning of the cDNA revealed the clone has similarity to a bacterial fermentation enzyme, the citrate lyase beta-subunit (CL-beta) . Northern blot and competitive reverse transcription-PCR (RT-PCR) analysis revealed up-regulation of the gene in the LM8 cell line . An RNA Master blot indicated that the mRNA encoding CL-beta is expressed abundantly in murine heart, liver, and kidney . A human expressed sequence tag (EST) database search suggested that a similar cDNA is expressed in humans . A gene with identical sequence is located on chromosome 13 in the genome database (Sanger centre, UK) . These data suggest that a citrate fermentation pathway may exist in eukaryotes including mammals.

Microbiology, 2001 Dec, 147(Pt 12), 3359 - 65
The antioxidant potential of pyruvate in the amitochondriate diplomonads Giardia intestinalis and Hexamita inflata; Biagini GA et al.; Giardia intestinalis and Hexamita inflata are microaerophilic protozoa which rely on fermentative metabolism for energy generation . These organisms have developed a number of antioxidant defence strategies to cope with elevated O(2) tensions which are inimical to survival . In this study, the ability of pyruvate, a central component of their energy metabolism, to act as a physiological antioxidant was investigated . The intracellular pools of 2-oxo acids in G . intestinalis were determined by HPLC . With the aid of a dichlorodihydrofluorescein diacetate-based assay, intracellular reactive oxygen species generation by G . intestinalis and H . inflata suspensions was monitored on-line . Addition of physiologically relevant concentrations of pyruvate to G . intestinalis and H . inflata cell suspensions was shown to attenuate the rate of H(2)O(2)- and menadione-induced generation of reactive oxygen species . In addition, pyruvate was also shown to decrease the generation of low-level chemiluminescence arising from the oxygenation of anaerobic suspensions of H . inflata . In contrast, addition of pyruvate to suspensions of respiring Saccharomyces cerevisiae was shown to increase the generation of reactive oxygen species . These data suggest that (i) in G . intestinalis and H . inflata, pyruvate exerts antioxidant activity at physiological levels, and (ii) it is the absence of a respiratory chain in the diplomonads which facilitates the observed antioxidant activity.

Bioorg Med Chem, 2002 Jan, 10(1), 185 - 8
5-demethylovalicin, as a methionine aminopeptidase-2 inhibitor produced by Chrysosporium; Son KH et al.; 5-Demethylovalicin was isolated from the fermentation broth Chrysosporium lucknowense and the structure was identified by spectroscopic methods . 5-Demethylovalicin inhibited the recombinant human MetAP-2 (IC(50)=17.7 nM) and the growth of human umbilical vein endothelial cells (HUVEC; IC(50)=100 nM) in cell proliferation assay without cytotoxicity on the transformed and cancer cell lines.

Plant J, 2001 Nov, 28(4), 431 - 41
Expression of antisense SnRK1 protein kinase sequence causes abnormal pollen development and male sterility in transgenic barley; Zhang Y et al.; A chimaeric gene was constructed comprising a wheat high molecular weight glutenin subunit gene promoter, a 304-bp sucrose non-fermenting-1-related (SnRK1) protein kinase sequence in the antisense orientation, and the cauliflower mosaic virus 35S RNA gene terminator . Transgenic barley plants containing the antisense SnRK1 chimaeric gene were produced by particle bombardment of barley immature embryos with the aim of obtaining plants expressing the antisense SnRK1 sequence in the seeds . Despite the fact that the promoter was expected to be active only in seeds, two independent transgenic lines were found to fail to transmit the transgene to the T1 generation . These T0 plants had matured and died before this was discovered, but subsequently four other independent transgenic lines were found to be affected in the same way . Cytological analysis of the pollen grains in these lines showed that about 50% were normal but the rest had arrested at the binucleate stage of development, were small, pear-shaped, contained little or no starch and were non-functional . The presence of antisense SnRK1 transcripts was detected in the anthers of the four lines analyzed and a ubiquitin promoter/UidA (Gus) gene, one of the marker genes codelivered with the antisense gene, was found to be expressed only in the abnormal pollen . Expression analyses confirmed that SnRK1 is expressed in barley anthers and that expression of one class of SnRK1 transcripts (SnRK1b) was reduced in the abnormal lines . All of the abnormal lines showed approximately 50% seed set, and none of the transgenes were detected in the T1 generation.

HIV Med, 2000 Oct, 1(4), 219 - 23
Detection of Mycoplasma fermentans in broncho-alveolar lavage fluid specimens from AIDS patients with lower respiratory tract infection; Ainsworth JG et al.; OBJECTIVE: To investigate the role of Mycoplasma fermentans in lower respiratory tract disease of HIV-positive patients . METHODS: A polymerase chain reaction (PCR) assay was used to detect M . fermentans in broncho-alveolar lavage (BAL) fluid and peripheral blood mononuclear cells (PBMCs) collected from 78 hospitalized HIV-positive patients with lower respiratory tract disease (the index group) . BAL specimens were also assessed from two control groups; 25 HIV-positive patients without respiratory symptoms and 46 patients with a respiratory illness who did not have risk factors for HIV . RESULTS: Seventy-one (91%) of the 78 patients who comprised the index group had AIDS . Sixty-one patients provided BAL and PBMC specimens; 16 provided a BAL specimen and one only a PBMC specimen; 15 (25%) of the 61 patients had M . fermentans positive BAL fluid, of whom 10 (67%) also had a positive PBMC specimen . In contrast, of the 46 patients who had a negative BAL fluid, only three (6.4%) had a positive PBMC sample (P < 0.00001 Fisher's exact test) . Overall, 21 (27%) of 77 patients had M . fermentans positive BAL fluid . Of these positive patients, 16 also had another microorganism in the BAL fluid and for five patients M . fermentans was detected alone . Compared with patients in the index group, none of the 46 BAL fluid specimens from patients at low risk of HIV infection was M . fermentans positive (P < 0.001, chi2 15.13) . Two (8%) of the 25 HIV-positive patients without respiratory symptoms had a M . fermentans positive BAL fluid, positivity that was also statistically different from the index group (P = 0.045, chi2 4.01) . CONCLUSIONS: M . fermentans frequently invades the lower respiratory tract of AIDS patients as an opportunist and may cause disease in some.

Biotechnol Prog, 2001 Nov-Dec, 17(6), 1079 - 83
Fluidized bed design parameters affecting novel lactic Acid downstream processing; Sosa AV et al.; Lactic acid purification was directly done from fermentation utilizing a fluidized bed column refilled with a strong anionic exchange resin . The purpose of this work was to study the influence of two important design parameters, bed-diameter (D) and bed-height (H), in the lactic acid binding and elution capacity of the matrix . By changing the settled bed height from 2.5 to 5 cm for each diameter of column analyzed it was possible to obtain an 50% increase in the binding capacity of the resin in all experiments . This fact was attributed to a higher contact time between the culture broth and the anionic resin produced by the increase of back mixing and lactic acid residence time.

Biotechnol Prog, 2001 Nov-Dec, 17(6), 1065 - 70
Packed bed column fermenter and kinetic modeling for upgrading the nutritional quality of coffee husk in solid-state fermentation; Brand D et al.; Studies were carried out to evaluate solid-state fermentation (SSF) for the upgradation of the nutritional quality of coffee husk by degrading the caffeine and tannins present in it . SSF was carried out by Aspergillus niger LPBx in a glass column fermenter using factorial design experiments and surface response methodology to optimize bioprocess parameters such as the substrate pH and moisture content and aeration rate . The first factorial design showed that the moisture content of the substrate and aeration rate were significant factors for the degradation of toxic compounds, which was confirmed by the second factorial design too . The kinetic study showed that the degradation of toxic compounds was related to the development of the mold and its respiration and also to the consumption of the reducing sugars present in coffee husk . From the values obtained experimentally for the oxygen uptake rate and CO(2) evolved, the system determined a biomass yield (Y(x/o)) of 3.811 (g of biomass).(g of consumed O(2))(-1) and a maintenance coefficient (m) of 0.0031 (g of consumed O(2)).(g biomass of biomass)(-1).h(-1) . The best results on the degradation of caffeine (90%) and tannins (57%) were achieved when SSF was carried out with a 30 mL.min(-1) aeration rate using coffee husk having a 55% initial moisture content . The inoculation rate did not affect the metabolization of the toxic compounds by the fungal culture . After SSF, the protein content of the husk was increased to 10.6%, which was more than double that of the unfermented husk (5.2%).

Biotechnol Prog, 2001 Nov-Dec, 17(6), 1055 - 60
Metabolic flux variation of Saccharomyces cerevisiae cultivated in a multistage continuous stirred tank reactor fermentation environment; Lin YH et al.; The technique of metabolic flux analysis was implemented to elucidate the flux balancing of Saccharomyces cerevisiae cultivated in a multistage continuous stirred tank reactor fermentation environment . The results showed that the majority of the substrate (97.70 +/- 0.49%) was funneled into the glycolytic pathway, while the remainder was subdivided between the pentose phosphate pathway and pathways for polysaccharide synthesis . At the pyruvate node, 87.30 +/- 1.38% of the flux was channeled through the reaction governed by pyruvate decarboxylase . Fluxes through the pyruvate dehydrogenase bypass were maintained at a constant level (82.65 +/- 1.47%) irrespective of the configuration of the fermentation setup . Activity through the TCA "cycle" was replenished by the reaction catalyzed by pyruvate carboxylase and by the transport of cytosolic oxaloacetate across the mitochondrial membrane . The CO(2) evolution rate varied as fermentation progressed; however, the yield coefficient of CO(2) remained at a constant value . Although a constant yield of ethanol (0.42 g of ethanol/g of glucose) was obtained, operations of the TCA cycle were gradually switched from partially reductive to partially oxidative pathways from the first fermenter to the fourth fermenter.

FEBS Lett, 2001 Nov 30, 509(1), 131 - 4
YFH1-mediated iron homeostasis is independent of mitochondrial respiration; Chen OS et al.; The human gene frataxin and its yeast homolog YFH1 affect mitochondrial function . Deficits in frataxin result in Friedreich ataxia, while deletion of YFH1 results in respiratory incompetence . We determined that as long as respiratory incompetent yeast express Yfh1p they do not accumulate excessive mitochondrial iron . Deletion of YFH1 in respiratory incompetent yeast results in mitochondrial iron accumulation, while the reintroduction of Yfh1p results in mitochondrial iron export . Further, overexpression of Yfh1p has no effect on oxygen consumption in wild-type yeast grown in either fermentative or respiratory carbon sources . We conclude that the effect of Yfh1p on mitochondrial iron metabolism is independent of respiratory activity.

Appl Biochem Biotechnol, 2001 Sep, 95(3), 221 - 55
Production of native and recombinant lipases by Candida rugosa: a review; Ferrer P et al.; The yeast Candida rugosa produces multiple lipase isoenzymes sharing high sequence homology but with some differences in their catalytic properties . The regulation of C . rugosa lipase (CRL) synthesis and secretion in C . rugosa obeys a complex pattern . Fermentation processes for both wild-type and mutant C . rugosa strains are available for lipase production . Native CRL preparations have been extensively used for biotransformations . However, their inherent mixture of isoforms with variable profiles complicates interpretation and brings into question the reproducibility achieved between preparations . Although heterologous CRLs gene expression had been hampered owing to a nonuniversal codon usage, recent advances have made heterologous CRLs available . This will expand and improve the industrial utility of CRLs even further . The purpose of this review is to provide a summary of the recent advances on the production of native and recombinant lipases by C . rugosa.

Appl Biochem Biotechnol, 2001 Sep, 95(3), 195 - 207
Manufacture of xylose-based fermentation media from corncobs by posthydrolysis of autohydrolysis liquors; Garrote G et al.; Milled corncob samples were mixed with water and heated to obtain a liquid phase containing oligosaccharides, sugars, and acetic acid as main reaction products (autohydrolysis reaction) . To hydrolyze the sugar oligomers to the correspondent monomers, sulfuric acid was added to the autohydrolysis liquors to reach 0.5-2 wt% of solution, and the reaction media were heated at 101.5-135 degrees C . With this operational procedure, sugar solutions suitable as fermentation media (containing xylose as the major component) were obtained . The kinetics of the posthydrolysis step was characterized on the basis of experimental data concerning the time courses of the concentrations of xylooligosaccharides, xylose, furfural, and acetic acid . The concentrations of other reaction byproducts (glucose or arabinose) were also measured.

Vet Microbiol, 2002 Jan 3, 84(1-2), 93 - 102
Identification of a new biotype of Actinomyces hyovaginalis in tissues of pigs during diagnostic bacteriological examination; Storms V et al.; Bacterial strains isolated from a large variety of necropsy samples of pigs and previously described as a phenotypical homogeneous group were shown to belong to the species Actinomyces hyovaginalis . This was unexpected because their colonial characteristics, as well as their origins, were very different from those originally reported for the vaginal strains on which the species description of A . hyovaginalis was based . Colonial morphology, as well as fermentation of cellobiose, reactions in hippurate and nitrate and production of beta-glucuronidase, allowed separation of the strains studied here from the vaginal strains . Analysis of tRNA intergenic length polymorphisms (tDNA-PCR), 16S rRNA-gene sequencing and DNA-DNA hybridizations were carried out and led to the proposal of a separate biotype within the species A . hyovaginalis . Since, the strains were isolated from different body sites, this biotype has been designated as the 'general' biotype of A . hyovaginalis, while the strains on which the original species description was based are designated as the 'vaginal' biotype.

Curr Microbiol, 2002 Jan, 44(1), 5 - 9
Effect of oleic acid on Oenococcus oeni strains and Malolactic fermentation in wine; Guerrini S et al.; A different capability to assimilate oleic acid from the culture medium has been demonstrated among malolactic Oenococcus oeni strains . Strains possessing higher percentages of oleic acid and its methylated derivative, dihydrosterculic acid, in their fatty acid profile showed higher cell viability and carried out a complete malolactic fermentation after their transfer into a wine lacking oleic acid . Wine supplementation with Tween 80 (polyoxyethylene-sorbitan-mono-oleate) enhanced cell survival of strains with lower capability to assimilate oleic acid and caused cell growth of strains with higher assimilative capacity, suggesting that oleic acid may act in wine as a survival factor for the former strains and as a growth factor for the latter strains . Practical consequences of these findings are also discussed.

J Biochem (Tokyo), 2001 Dec, 130(6), 873 - 8
Deletion of mitochondrial ATPase inhibitor in the yeast Saccharomyces cerevisiae decreased cellular and mitochondrial ATP levels under non-nutritional conditions and induced a respiration-deficient cell-type; Lu YM et al.; T(1), a mutant yeast lacking three regulatory proteins of F(1)F(o)ATPase, namely ATPase inhibitor, 9K protein and 15K protein, grew on non-fermentable carbon source at the same rate as normal cells but was less viable when incubated in water . During the incubation, the cellular ATP content decreased rapidly in the T(1) cells but not in normal cells, and respiration-deficient cells appeared among the T(1) cells . The same mutation was also induced in D26 cells lacking only the ATPase inhibitor . Overexpression of the ATPase inhibitor in YC63 cells, which were derived from the D26 strain harboring an expression vector containing the gene of the ATPase inhibitor, prevented the decrease of cellular ATP level and the mutation . Isolated T(1) mitochondria exhibited ATP hydrolysis for maintenance of membrane potential when antimycin A was added to the mitochondrial suspension, while normal and YC63 mitochondria continued to show low hydrolytic activity and low membrane potential . Thus, it is likely that deletion of the ATPase inhibitor induces ATPase activity of F(1)F(o)ATPase to create a dispensable membrane potential under the non-nutritional conditions and that this depletes mitochondrial and cellular ATP . The depletion of mitochondrial ATP in turn leads to occurrence of aberrant DNA in mitochondria.

Int J Plant Sci, 2001 Mar, 162(2), 249 - 55
Evidence of root zone hypoxia in Brassica rapa L . grown in microgravity; Stout SC et al.; A series of experiments was conducted aboard the U.S . space shuttle and the Mir space station to evaluate microgravity-induced root zone hypoxia in rapid-cycling Brassica (Brassica rapa L.), using both root and foliar indicators of low-oxygen stress to the root zone . Root systems from two groups of plants 15 and 30 d after planting, grown in a phenolic foam nutrient delivery system on the shuttle (STS-87), were harvested and fixed for microscopy or frozen for enzyme assays immediately postflight or following a ground-based control . Activities of fermentative enzymes were measured as indicators of root zone hypoxia and metabolism . Following 16 d of microgravity, ADH (alcohol dehydrogenase) activity was increased in the spaceflight roots 47% and 475% in the 15-d-old and 30-d-old plants, respectively, relative to the ground control . Cytochemical localization showed ADH activity in only the root tips of the space-grown plants . Shoots from plants that were grown from seed in flight in a particulate medium on the Mir station were harvested at 13 d after planting and quick-frozen and stored in flight in a gaseous nitrogen freezer or chemically fixed in flight for subsequent microscopy . When compared to material from a high-fidelity ground control, concentrations of shoot sucrose and total soluble carbohydrate were significantly greater in the spaceflight treatment according to enzymatic carbohydrate analysis . Stereological analysis of micrographs of sections from leaf and cotyledon tissue fixed in flight and compared with ground controls indicated no changes in the volume of protoplast, cell wall, and intercellular space in parenchyma cells . Within the protoplasm, the volume occupied by starch was threefold higher in the spaceflight than in the ground control, with a concomitant decrease in vacuolar volume in the spaceflight treatment . Both induction of fermentative enzyme activity in roots and accumulation of carbohydrates in foliage have been repeatedly shown to occur in response to root zone oxygen deprivation . These results indicate that root zone hypoxia is a persistent challenge in spaceflight plant growth experiments and may be caused by microgravity-induced changes in fluid and gas distribution.

Water Sci Technol, 2001, 44(7), 123 - 8
Non-point pollution from China's rural areas and its countermeasures; Yin CQ et al.; Most lakes in the eastern part of China are eutrophic and non-point pollution accounts for more than half of the nutrient load to the lakes and reservoirs . Some efforts have been made to reduce the non-point source pollution in the catchments of sensitive water bodies . Technologies for the control of non-point pollution in Chinese rural areas are multipond systems, biogas fermentation, hilly area ecological agriculture, constructed wetlands, ecotone engineering and others . They are effective in the removal of nutrients from the runoff water or reduction of waste, and they are used with multi-purposes . To control non-point pollution, the cooperation with farmers and other residents in the countryside is the key to success, and the program has to consider their benefits . There are still many difficulties with its control, and more efforts are needed to develop suitable technologies and environmental education.

Appl Environ Microbiol, 2001 Dec, 67(12), 5705 - 14
Successional changes in an evolving anaerobic chlorophenol-degrading community used to infer relationships between population structure and system-level processes; Becker JG et al.; The response of a complex methanogenic sediment community to 2-chlorophenol (2-CP) was evaluated by monitoring the concentrations of this model contaminant and important metabolic intermediates and products and by using rRNA-targeted probes to track several microbial populations . Key relationships between the evolving population structure, formation of metabolic intermediates, and contaminant mineralization were identified . The nature of these relationships was intrinsically linked to the metabolism of benzoate, an intermediate that transiently accumulated during the mineralization of 2-CP . Before the onset of benzoate fermentation, reductive dehalogenation of 2-CP competed with methanogenesis for endogenous reducing equivalents . This suppressed H(2) levels, methane production, and archaeal small-subunit (SSU)-rRNA concentrations in the sediment community . The concentrations of bacterial SSU rRNA, including SSU rRNA derived from "Desulfovibrionaceae" populations, tracked with 2-CP levels, presumably reflecting changes in the activity of dehalogenating organisms . After the onset of benzoate fermentation, the abundance of Syntrophus-like SSU rRNA increased, presumably because these syntrophic organisms fermented benzoate to methanogenic substrates . Consequently, although the parent substrate 2-CP served as an electron acceptor, cleavage of its aromatic nucleus also influenced the sediment community by releasing the electron donors H(2) and acetate . Increased methane production and archaeal SSU-rRNA levels, which tracked with the Syntrophus-like SSU-rRNA concentrations, revealed that methanogenic populations in particular benefited from the input of reducing equivalents derived from 2-CP.

J Appl Microbiol, 2001 Nov, 91(5), 916 - 21
Characterization of a broad pH range protease of Candida caseinolytica; Poza M et al.; AIMS: The study of a protease secreted by Candida caseinolytica for use in future industrial applications . METHODS AND RESULTS: Growth of Candida caseinolytica on a medium containing milk induced a rapid production of an extracellular enzyme able to hydrolyse casein . The crude extract was applied to both Sephacryl S-200 and DEAE-Biogel A columns, obtaining one peak of activity showing a molecular mass of approximately 30 kDa and three active peaks, respectively . These four peaks showed the same biochemical parameters . In all cases, an extremely broad pH range of action was determined . CONCLUSIONS: Candida caseinolytica secretes high levels of an extracellular protease when grown either in rotary shakers or in batch-fermenters . SIGNIFICANCE AND IMPACT OF THE STUDY: The biochemical properties of this enzyme suggest its possible industrial application in the brewing industry, in the formulation of certain type of detergents and in the fur and leather industries, among others.

J Anim Sci, 2001 Oct, 79(10), 2713 - 8
Effects of carbohydrates from citrus pulp and hominy feed on microbial fermentation in continuous culture; Ariza P et al.; Eight dual-flow continuous-culture fermenters were used to evaluate the effect of neutral detergent-soluble carbohydrates (NDSC) on fermentation by ruminal microorganisms . Citrus pulp and hominy feed were added to a basal diet as sources of NDSC, with citrus pulp providing neutral detergent-soluble fiber (NDSF) in the form of pectic substances and with hominy feed in the form of starch . The basal diet contained 26.7% corn silage, 6.0% alfalfa hay and 3.8% cottonseed hulls on a DM basis . The dried citrus pulp diet contained on a DM basis 17.2% CP, 34.7% NDF, 33.7% NDSC, and 14.4% NDSF, whereas the hominy feed diet contained 17.9% CP, 33.2% NDF, 35.9% NDSC, and 8.8% NDSF . Organic matter, DM, and NDF and ADF digestion were not affected by source of carbohydrate . Ammonia N concentration was greater (P < 0.05) for the hominy feed diet (14.2 mg/100 mL) than for the dried citrus pulp diet (9.3 mg/100 mL) . Total N, nonammonia N, microbial N, and dietary N flows were not affected by treatments; however, the efficiency of microbial protein synthesis was greater (P = 0.055) for the dried citrus pulp diet than for the hominy feed diet (30.6 vs 27.8 g of bacterial N/kg of OM truly digested) . Results from this experiment indicate that NDSF from citrus pulp can provide similar sources of energy compared with starch from hominy feed to support ruminal microbial growth.

J Anim Sci, 2001 Oct, 79(10), 2704 - 12
Supplemental soybean oil or corn for beef heifers grazing summer pasture: effects on forage intake, ruminal fermentation, and site and extent of digestion; Brokaw L et al.; Nine Angus x Gelbvieh heifers (average BW = 347 +/- 2.8 kg) with ruminal and duodenal cannulas were used in a split-plot designed experiment to determine the effects of soybean oil or corn supplementation on intake, OM, NDF, and N digestibility . Beginning June 8, 1998, heifers continually grazed a 6.5-ha predominantly bromegrass pasture and received one of three treatments: no supplementation (Control); daily supplementation of cracked corn (Corn) at 0.345% of BW; or daily supplementation (0.3% of BW) of a supplement containing cracked corn, corn gluten meal, and soybean oil (12.5% of supplemental DM; Oil) . Soybean oil replaced corn on a TDN basis and corn gluten meal was included to provide equal quantities of supplemental TDN and N . Three 23-d periods consisted of 14 d of adaptation followed by 9 d of sample collections . Treatment and sampling period effects were evaluated using orthogonal contrasts . Other than crude fat being greater (P = 0.01) for supplemented heifers, chemical and nutrient composition of masticate samples collected via ruminal evacuation did not differ (P = 0.23 to 0.56) among treatments . Masticate NDF and ADF increased quadratically (P < or = 0.003) and N decreased linearly (P = 0.0001) as the grazing season progressed . Supplementation did not influence (P = 0.37 to 0.83) forage OM intake, total and lower tract OM digestibility, ruminal and total tract NDF digestibility, or total ruminal VFA; however, supplemented heifers had lower ruminal molar proportions of acetate (P = 0.01), higher ruminal molar proportions of butyrate (P = 0.007), and greater quantities of OM digested in the rumen (P = 0.10) and total tract (P = 0.02) . As the grazing season progressed, total tract OM and N and ruminal NH3 concentrations and NDF digestibility decreased quadratically (P < or = 0.04) . Microbial N flow (P = 0.09) and efficiency (P = 0.04) and postruminal N disappearance (P = 0.02) were greater for Control heifers and declined linearly (P < or = 0.02) as the grazing season advanced . Depressed microbial N flow seemed to be more pronounced for Oil than for the Corn treatment . Although total digestible OM intake increased with supplementation, metabolizable protein supply was reduced in supplemented heifers . Therefore, feeding low levels of supplemental grain with or without soybean oil is an effective strategy to increase dietary energy for cattle grazing high-quality forages, but consideration should be given to reduced supply of metabolizable protein.

Acta Microbiol Pol, 2001, 50(2), 139 - 47
Production of intracellular milk-clotting enzyme in submerged cultures of Fusarium subglutinans; Ghareib M et al.; Fusarium subglutinans (Wollenweber and Reinking) Nelson et al . was found to produce intracellular milk-clotting enzyme (MCE) with good milk-clotting activity (MCA) . The crude activity of the produced enzyme was recorded as optimum at 55 degrees C and pH 4.5 . The highest yield i.e . 78.43 SU/mg dry biomass was obtained after 4 days of rotary shaking at 30 degrees C when the fermentation medium containes wheat flour 2%, glucose 1% and (NH4)2SO4 0.1% with an initial pH value 6.0 . Under these conditions, the maximum ratio of MCA to proteolytic activity (PA) amounting to 603.31 SU/PU mg(-1) was also achieved . Production of intracellular MCE by F . subglutinans was assumed to be active growth-associated type . This enzyme preparation was less active than the calf rennet, but was superior to those of Meito's and Pfizer's rennets.

Zhong Yao Cai, 2001 Aug, 24(8), 561 - 3
{Identification of red kojic from different habitats with clustering analysis by near-infrared diffuse reflectance spectrometry}; Xing W et al.; OBJECTIVE: To provide a new method for identifying Red kojic . METHODS: Being controled with the Aspergillus terreus, near-infrared diffuse reflectance spectroscopy combining with clusering analysis was used in the identification of Red Kojic made by M . purpureus fermentation from 18 different habitats . RESULTS: We can easily distinguish the Red Kojic from different habitats and the Aspergillus terreus . The results are consistent in some degree with that of morphologic study . CONCLUSION: This method is a new, rapid, simple and low cost assay technique being able to be used in the quality control of Red Kojic.

J Microbiol Methods, 2001 Dec, 47(3), 293 - 8
Viability staining and terminal deoxyribonucleotide transferase-mediated dUTP nick end labelling of the mycelium in submerged cultures of Streptomyces antibioticus ETH7451; Fernandez M et al.; Viability stain and terminal deoxyribonucleotide transferase-mediated dUTP nick end labelling (TUNEL) have been applied to submerged cultures of Streptomyces antibioticus ETH7451, the last technique after a suitable permeabilization treatment . Areas of dead mycelium can be clearly delineated by the viability stain within the network of hyphae which forms the mycelial masses characteristic of the submerged cultures . In addition, the TUNEL reaction shows that DNA fragmentation accompanies the death processes in the mycelium . These techniques permit the investigation of the influence of the medium and nutritional conditions on the viability of the cells . This has relevant biotechnological implications for the study of these important filamentous bacteria in the industrial fermentation processes . These techniques also allow a straight forward analysis of the physical and chemical reagents which provoke damage in Streptomyces DNA.

J Microbiol Methods, 2001 Dec, 47(3), 257 - 72
Applications of DNA microarrays in microbial systems; Ye RW et al.; DNA microarray technology allows a parallel analysis of RNA abundance and DNA homology for thousands of genes in a single experiment . Over the past few years, this powerful technology has been used to explore transcriptional profiles and genome differences for a variety of microorganisms, greatly facilitating our understanding of microbial metabolism . With the increasing availability of complete microbial genomes, DNA microarrays are becoming a common tool in many areas of microbial research, including microbial physiology, pathogenesis, epidemiology, ecology, phylogeny, pathway engineering and fermentation optimization.

J Agric Food Chem, 2001 Nov, 49(11), 5556 - 9
Fate of mucilage cell wall polysaccharides during coffee fermentation; Avallone S et al.; Effects of a 20-h fermentation on cell wall polysaccharides from the mucilage of pulped coffee beans were examined and compared to those of unfermented beans, on alcohol insoluble residues (AIRs), their hot-water-soluble crude pectic substances (PECTs), and their hot-water-insoluble residues (RESs) . Yields and compositions were very similar: AIRs, which consisted of approximately 30% highly methylated pectic substances, approximately 9% cellulose, and approximately 15% neutral noncellulosic polysaccharides, exhibited no apparent degradation . However, PECTs from fermented beans were shown to have undergone a slight reduction of their intrinsic viscosity and weight-average molecular weight by capillary viscosimetry and high-performance size-exclusion chromatography . After fermentation, hot-water-insoluble pectic substances of RES exhibited partial de-esterification . Removal of coffee bean mucilage by natural fermentation seems to result from a restricted pectolysis, the mechanism of which remains to be elucidated.

J Agric Food Chem, 2001 Nov, 49(11), 5494 - 501
Determination of free and conjugated indole-3-acetic acid, tryptophan, and tryptophan metabolites in grape must and wine; Hoenicke K et al.; Tryptophan (Trp) and its metabolites, especially indole-3-acetic acid (IAA), are considered to be potential precursors of 2-aminoacetophenone (AAP), an aroma compound that causes an "untypical aging off-flavor" (UTA) in Vitis vinifera wines . In this study, RP-HPLC with fluorescence detection was used for the qualitative and quantitative analysis of Trp and Trp metabolites in grape musts and wines to which different viticultural measures had been applied (time of harvest, soil treatment, leaf plucking, vine prune) . An alkaline hydrolysis was developed to release bound IAA and Trp . A sensitive and selective determination of different Trp metabolites was achieved after solid phase extraction using a strong anion exchange material . In the examined grape musts, more than 95% of the total IAA was bound either as ester conjugate or as amide conjugate . Free IAA and other Trp metabolites were below the detection limit (<3 microg/L) or could be determined only in traces . Their amounts increased significantly during fermentation, whereas the amount of Trp decreased . It could be shown that the different viticultural measures applied (except the vine prune) as well as the climatic conditions of the vintage exhibited significant influences on the amounts of Trp and Trp metabolites in grape musts or wines.

J Agric Food Chem, 2001 Nov, 49(11), 5450 - 4
Use of fungal phytase to improve breadmaking performance of whole wheat bread; Haros M et al.; The possible use of phytase as a breadmaking improver has been tested in whole wheat breads by adding different amounts of fungal phytase . The effect of phytase addition on the fermentation stage and the final bread quality was analyzed . The phytase addition shortened the fermentation period, without affecting the bread dough pH . Regarding the whole wheat bread, a considerable increase of the specific bread volume, an improvement of the crumb texture, and the width/height ratio of the bread slice were obtained . An in vitro assay revealed that the improving effect of phytase on breadmaking might be associated with the activation of alpha-amylase, due to the release of calcium ions from calcium-phytate complexes promoted by phytase activity . As a conclusion, phytase offers excellent possibilities as a breadmaking improver, with two main advantages: first, the nutritional improvement produced by decreasing phytate content, and second, all the benefits produced by alpha-amylase addition can be obtained by adding phytase, which promotes the activation of endogenous alpha-amylase.

J Agric Food Chem, 2001 Nov, 49(11), 5331 - 5
Study of soybean seed coat components and their relationship to water absorption; Mullin WJ et al.; The occurrence of hard or "stone" seeds in shipments of food grade soybeans can cause serious problems in processing, particularly in the preparation of fermented soy products . Climatic conditions during the growing season and as the seed matures may trigger the production of hard seeds . Total water absorption of soybeans is also a significant parameter in assessing quality for export markets . The seed coats of six varieties of soybeans, covering a wide range of water absorption and stone seed content, were analyzed for ash and cations, protein, lignin, and complex carbohydrates . The water absorption characteristics and macrochemical constituents of the whole seed were also determined . The results indicated that there was no correlation between the concentration of any of the cations and the occurrence of hard seeds . The results from analysis of the complex carbohydrates indicated there were differences in hemicellulose content of seed coat fractions, particularly xylans, that correlated with the water uptake ratio and the occurrence of hard seeds.

J Agric Food Chem, 2001 Nov, 49(11), 5207 - 9
Enzymatic extraction and transformation of glucovanillin to vanillin from vanilla green pods; Ruiz-Teran F et al.; Glucovanillin was extracted from green pods and simultaneously transformed to vanillin by a combination of enzyme activities involving cell wall degradation and glucovanillin hydrolysis . The reaction is best carried out with 47.5% v/v aqueous ethanol solution during 8 h at 70 degrees C, in a two-step enzymatic reaction using Viscozyme followed by Celluclast, two commercial enzymatic products containing mainly pectinase and cellulase activities, respectively . The extractive reaction proceeded with high efficiency with an amount of extracted vanillin 3.13 times higher than the one obtained with the Soxhlet method . The classical curing/extraction process results in 1.1-1.8 g of vanillin/100 g of dry pods . It is concluded that the enzymatic reaction may substitute the microbial process involved in tissue fermentation previous to vanillin extraction with the simultaneous hydrolysis of glucovanillin.

J Antibiot (Tokyo), 2001 Sep, 54(9), 703 - 9
Novel cytokine production inhibitors produced by a basidiomycete, Marasmiellus sp; Ichikawa K et al.; New cytokine production inhibitors, CJ-14,877 (I) and CJ-14,897 (II), were isolated from the fermentation broth of a basidiomycete, Marasmiellus sp . CL21624 . Their structures were determined to be methyl-(7S,8S)-5-(7,8-dihydroxypropyl)pyridine-2-carboxylate and methyl-(7S,8S)-5-(8-acetoxy-7-hydroxypropyl)pyridine-2-carboxylate {corrected}, respectively, by spectroscopic analyses . These compounds showed inhibitory activities for lipopolysaccharide-induced production of interleukin-1beta and tumor necrosis factor-alpha in human whole blood with IC50 values of the range from 0.059 to 2.6 microM.

J Antibiot (Tokyo), 2001 Sep, 54(9), 697 - 702
Cytokine production inhibitors produced by a fungus, Oidiodendron griseum; Ichikawa K et al.; A series of diterpenes were isolated from the fermentation broth of a fungus, Oidiodendron griseum CL37215 . The diterpenes were identified as LL-Z1271alpha, LL-Z1271gamma, CJ-14,445, PR 1388, CJ-14,604 and a new diterpene, CJ-14,515 . They inhibited both lipopolysaccharide-induced interleukin-1beta and tumor necrosis factor-alpha production in human whole blood with IC50s of the range from 0.049 to 100 microM.

J Vet Med Sci, 2001 Oct, 63(10), 1071 - 5
Postnatal development of glucose transporter proteins in bovine skeletal muscle and adipose tissue; Abe H et al.; Facilitated diffusion of glucose across the plasma membrane is mediated by a family of glucose transporter (GLUT) . GLUT1 is ubiquitously present in all tissues and involved in cellular glucose uptake, while GLUT4 plays a key role in cellular glucose uptake stimulated by insulin in skeletal muscles and adipose tissue . To examine the postnatal change in the GLUTs of ruminants, the protein levels of GLUT1 and GLUT4 were measured by Western blot analysis of skeletal muscles, adipose tissue and brain of Holstein male calves aged from 0 to 12 months . Analysis of rumen short chain volatile fatty acids revealed that rumen fermentation increased around 2-3 months old . The GLUT1 level did not change in all tissues examined during the postnatal period, while the GLUT4 levels in skeletal muscle and subcutaneous adipose tissue decreased gradually, and at 12 month old, it was about 40% of those seen at 0 month old . These results are contrast to those in non-ruminant species, in which GLUT4 increases during postnatal development, and may be related to the insulin-resistance seen in adult ruminants.

Vojnosanit Pregl, 2001 Jul-Aug, 58(4), 415 - 9
{Use of mycophenolate mofetil in kidney transplantation}; Hrvacevic R et al.; Mycophenolate mofetil (MMF) is a new immunosuppressive agent for the prevention of renal allograft rejection . MMF is a prodrug of mycophenolic acid (MPA), a fermentation product of several Penicillium species of fungus . MPA acts at a late stage in T and B lymphocyte proliferation by selective, uncompetitive and reversible inhibition of inosine monophosphate dehydrogenase, a key enzyme in the de novo pathway of purine nucleotide synthesis . The three large studies individually and the combined (pooled) 1-year patient efficacy data have shown that MMF, given in combination with cyclosporine and corticosteroids, significantly reduces the incidence of acute rejection episodes (by 50%), without detectable difference in patient mortality . Analysis of secondary efficacy endpoints revealed that patients treated with MMF required less additional immunosuppressive therapy for treatment of acute rejection episodes and showed better renal function . In another studies, the efficacy of MMF in the treatment of first acute rejection episodes and in the treatment of refractory, acute, cellular renal transplant rejections has been shown . The principal adverse events associated with MMF administration included diarrhea, vomiting, leukopenia and a higher frequency of certain types of infections . The efficacy of MMF for the treatment of chronic allograft nephropathy is controversial . The ability of MMF to reduce the occurrence of acute rejection episodes and improve allograft function may have significant implications for promoting the long-term survival of renal allografts, but we need long-term observations to prove this benefit.

Curr Issues Intest Microbiol, 2000 Mar, 1(1), 25 - 37
Starches, resistant starches, the gut microflora and human health; Bird AR et al.; Starches are important as energy sources for humans and also for their interactions with the gut microflora throughout the digestive tact . Largely, those interactions promote human health . In the mouth, less gelatinised starches may lower risk of cariogensis . In the large bowel, starches which have escaped small intestinal digestion (resistant starch), together with proteins, other undigested carbohydrates and endogenous secretions are fermented by the resident microflora . The resulting short chain fatty acids contribute substantially to the normal physiological functions of the viscera . Specific types of resistant starch (e.g . the chemically modified starches used in the food industry) may be used to manipulate the gut bacteria and their products (including short chain fatty acids) so as to optimise health . In the upper gut, these starches may assist in the transport of probiotic organisms thus promoting the immune response and suppressing potential pathogens . However, it appears unlikely that current probiotic organisms can be used to modulate large bowel short chain fatty acids in adults although resistant starch and other prebiotics can do so . Suggestions that starch may exacerbate certain conditions (such as ulcerative colitis) through stimulating the growth of certain pathogenic organisms appear to be unfounded . Short chain fatty acids may modulate tissue levels and effects of growth factors in the gut and so modify gut development and risk of serious disease, including colo-rectal cancer . However, information on the relationship between starches and the microflora is relatively sparse and substantial opportunities exist both for basic research and food product development.

Bioresour Technol, 2002 Jan, 81(1), 33 - 44
A comparison of liquid hot water and steam pretreatments of sugar cane bagasse for bioconversion to ethanol; Laser M et al.; Sugar cane bagasse was pretreated with either liquid hot water (LHW) or steam using the same 25 l reactor . Solids concentration ranged from 1% to 8% for LHW pretreatment and was > or = 50% for steam pretreatment . Reaction temperature and time ranged from 170 to 230 degrees C and 1 to 46 min, respectively . Key performance metrics included fiber reactivity, xylan recovery, and the extent to which pretreatment hydrolyzate inhibited glucose fermentation . In four cases, LHW pretreatment achieved > or = 80% conversion by simultaneous saccharification and fermentation (SSF) . > or = 80% xylan recovery, and no hydrolyzate inhibition of glucose fermentation yield . Combined effectiveness was not as good for steam pretreatment due to low xylan recovery . SSF conversion increased and xylan recovery decreased as xylan dissolution increased for both modes . SSF conversion, xylan dissolution . hydrolyzate furfural concentration, and hydrolyzate inhibition increased, while xylan recovery and hydrolyzate pH decreased, as a function of increasing LHW pretreatment solids concentration (1-8%) . These results are consistent with the notion that autohydrolysis plays an important . if not exclusive, role in batch hydrothermal pretreatment . Achieving concurrently high (greater than 90%) SSF conversion and xylan recovery will likely require a modified reactor configuration (e.g . continuous percolation or base addition) that better preserves dissolved xylan.

Bioresour Technol, 2002 Jan, 81(1), 19 - 24
Two-stage anaerobic fermentation of organic waste in CSTR and UFAF-reactors; Held C et al.; The mechanically separated liquid fraction of organic waste from households was used as a substrate for anaerobic fermentation . A two-step system consisting of a 2001 continuously stirred tank reactor (CSTR) and a 501 upflow anaerobic filter filled with glass foam pearls was constructed . The CSTR was operated for 5 months with a loading rate of 9.8 kg CSB m(-3) day(-1) . At a resulting hydraulic retention time (HRT) of 24 days, 68% COD was degraded and a gas productivity of 4.0 m3 m(-3) day(-1) was achieved . Further digestion of the CSTR output was separately optimised in a 20 l-UFAF and based on these results a 50 l-UFAF was connected to the CSTR . At a resulting hydraulic retention time (HRT) of 6 days 38% COD was degraded and a gas productivity of 1.8 m3 m(-3) day(-1) was achieved with the 50 l-UFAF . Thus, the overall degradation efficiency of the two-phase system was 80% . The methane content (61%) of the biogas produced in the 50 l-UF

Eur J Cancer B Oral Oncol, 1993 Oct, 29B(4), 299 - 302
Oral mucosal changes related to smokeless tobacco usage: research findings in Scandinavia; Axell TE; Smokeless tobacco is used in all Scandinavian countries . By far the highest consumption is recorded in Sweden, where the highest sales figures in the world can be found . Moist non-fermented snuff with a pH value of 8-9 comprises over 99% of the products . Only a few tons per year of chewing tobacco are sold . Moist snuff as it is used in Scandinavia today gives rise to oral mucosal changes which are reversible after cessation of the habit . The use of portion-bags, and even more so the use of chewing tobacco, seems to be associated with less pronounced changes than the use of loose snuff . The daily amount of snuff used and hours of daily use seem to have a greater impact on the risk for development of more pronounced changes as recorded clinically and histologically than the number of years with the habit and/or age of the subject . Gingival recessions are much more frequently found among users of loose snuff than among users of portion-bag-packed snuff and they seem to be irreversible.

Curr Opin Clin Nutr Metab Care, 2001 Nov, 4(6), 571 - 9
Pre-, pro- and synbiotics; Bengmark S; Approximately 70% of the immune system is localized in the gastrointestinal tract . The saliva and gastrointestinal secretions, as well as flora (probiotics) and supplied fibres (prebiotics), are important for optimal function . Probiotic bacteria have been shown to influence the immune system through several molecular mechanisms . Pre-, pro- and synbiotics (products produced by fermentation) offer both protection against and cure of a variety of endemic and acute diseases . This review summarizes the present experience in various forms of diarrhoea, inflammatory bowel disease, and Helicobacter infections, in intensive care patients and in connection with extensive surgery.

Curr Opin Clin Nutr Metab Care, 2001 Nov, 4(6), 483 - 7
Effects of vitamin K on calcium and bone metabolism; Zittermann A; The K vitamins, a group of napthoquinones, are required for the carboxylation of a limited number of proteins including the bone matrix protein osteocalcin . Vitamin K1 (phylloquinone) and vitamin K2 (menaquinones), differ regarding food source (green vegetables and fermented products, respectively), bioavailability and intermediate metabolism . Epidemiological studies provide evidence for an association between a low vitamin K intake and an enhanced osteoporotic fracture risk . Doses of vitamin K1 up to 15 times the current recommended dietary allowance have successfully been used to reduce the percentage of undercarboxylated osteocalcin in the circulation . Studies demonstrating clear beneficial effects on bone health, however, are still lacking . In contrast, therapy with very high pharmacological doses of the vitamin K2 menatetrenone has impressively been used to prevent further bone mineral loss and fracture risk in osteoporotic patients.

Sheng Wu Gong Cheng Xue Bao, 2001 Jul, 17(4), 441 - 4
{Dynamic variance of intracellular metabolic energies under rhythmical control for dissolved oxygen in PHB mixed cultivation}; Qian ZW et al.; The mixed cultivation using cheaper carbon source-wasted food material contained glucose and lactate at the same time was conducted in 5L fermentor, within which glucose was converted to lactate by L . delbrueckii in anaerobic condition and the lactate was converted to PHB by R . eutropha in aerobic condition . Considering dissolved oxygen concentration may affect the level of intracellular ATP and NADPH of the metabolic pathways for R . eutropha in lactate under autotrophy or heterotrophy, rhythmical oscillated control for DO based on chaos control method was consequently presented . This method was employed to satisfy two strains for opposite oxygen preferences, moreover, excite the intracellular metabolic energy simultaneously . The values examined through spectrophotofluorimetry represented that both ATP and NADPH exhibited fluctuations in accordance with the DO rhythm . By means of this control design, the concentration of PHB can be doubled than the usual under stable DO control.

Arch Microbiol, 2001 Nov, 176(5), 329 - 38
Sugar utilization in the hyperthermophilic, sulfate-reducing archaeon Archaeoglobus fulgidus strain 7324: starch degradation to acetate and CO2 via a modified Embden-Meyerhof pathway and acetyl-CoA synthetase (ADP-forming); Labes A et al.; The hyperthermophilic, sulfate-reducing archaeon Archaeoglobus fulgidus strain 7324, rather than the type strain VC16, was found to grow on starch and sulfate as energy and carbon source . Fermentation products and enzyme activities were determined in starch-grown cells and compared to those of cells grown on lactate and sulfate . During exponential growth on starch, 1 mol of glucose-equivalent was incompletely oxidized with sulfate to approximately 2 mol acetate, 2 mol CO2 and 1 mol H2S . Starch-grown cells did not contain measurable amounts of the deazaflavin factor F420 (<0.03 nmol/mg protein) and thus did not show the F420-specific green-blue fluorescence . In contrast, lactate (1 mol) was completely oxidized with sulfate to 3 mol CO2 by strain 7324, and lactate-grown cells contained high amounts of F420 (0.6 nmol/mg protein) . In extracts of starch-grown cells, the following enzymes of a modified Embden-Meyerhof pathway were detected: ADP-dependent hexokinase (ADP-HK), phosphoglucose isomerase, ADP-dependent 6-phosphofructokinase (ADP-PFK), fructose-1,6-phosphate aldolase, glyceraldehyde-3-phosphate:ferredoxin oxidoreductase (GAP:FdOR), phosphoglycerate mutase, enolase, and pyruvate kinase (PK) . Specific activities of ADP-HK, ADP-PFK, GAP:FdOR, and PK were significantly higher in starch-grown cells than in lactate-grown cells, indicating induction of these enzymes during starch catabolism . Pyruvate conversion to acetate involved pyruvate:ferredoxin oxidoreductase and ADP-forming acetyl-CoA synthetase . The findings indicate that the archaeal sulfate reducer A . fulgidus strain 7324 converts starch to acetate via a modified Embden-Meyerhof pathway and acetyl-CoA synthetase (ADP-forming) . This is the first report of growth of a sulfate reducer on starch, i.e . on a polymeric sugar.

J Dairy Sci, 2001 Oct, 84(10), 2240 - 9
Strategies for increasing energy density of dry cow diets; Rabelo E et al.; The objective of this trial was to compare the effects of increasing dietary energy density from 1.51 to 1.65 Mcal/kg of dry matter (DM) by replacing forage with concentrate or by further increasing concentrate via the substitution of corn silage and alfalfa silage by a mixture of straw, starch, and soybean meal . Our hypothesis was that the latter diet would be more glucogenic while increasing rumen fill and be potentially desirable for transition cows . Nine far-off dry cows (greater than 3 wk before parturition at the end of the trial) were fed three diets: low energy diet, {LE, 1.51 Mcal/kg of DM, 14.0% crude protein (CP) and 35% nonfiber carbohydrates (NFC)}, high energy diet, (HE, 1.65 Mcal/kg of DM, 13.9% CP and 39.5% NFC) and high energy diet, where a portion of alfalfa and corn silage was replaced by straw, soybean meal, and cornstarch (HES, 1.65 Mcal/kg of DM, 13.5% CP and 40.5% NFC) . The experiment was a replicated 3 x 3 Latin square design with 21-d periods . Six cows from two squares were used to examine kinetics of DM disappearance from nylon bags suspended in the rumen . Two contrasts of interest were: LE versus HE, HES (effects of energy density) and HE versus HES (method of increasing energy density) . Increasing energy density increased the potentially degradable (B) and decreased the undergradable (C) DM fractions of the diets . Because HES had greater B and a faster rate of degradation of fraction B (k), effective rumen degradable DM (ERDDM) was higher in HES compared to HE . Cows fed high energy diets had greater DM intake . No differences in DM intake were observed between HE and HES . Rumen volume or DM pool sizes were not affected by treatment . High energy diets increased total ruminal fluid volatile fatty acid concentration compared with LE . Propionate concentration was higher in cows fed high energy diets compared with cows fed LE . The partial replacement of alfalfa and corn silage by straw, soybean meal, and cornstarch further increased propionate concentration . The greatest increase in serum insulin concentration following feeding was observed in cows fed HE . Cows consuming high energy diets had lower plasma nonesterified fatty acids (NEFA) before and after feeding . The HES diet was less effective in decreasing plasma NEFA concentration after feeding compared to HE . In conclusion, increasing diet energy density of far-off dry cows positively affected DMI, ruminal propionate, serum insulin, and plasma NEFA . Increasing energy density with a blend of feeds that represent extremes in rates of carbohydrate fermentation may be a strategy to provide greater amounts of glucogenic precursors . Applicability of this strategy should be examined in transition cows.

J Dairy Sci, 2001 Oct, 84(10), 2227 - 30
Cracked dry or finely ground high moisture shelled corn as a supplement for grazing cows; Wu Z et al.; Feeding shelled corn as the primary supplement in cracked dry form or ground high moisture form to grazing cows was studied in an experiment using 32 cows in late lactation . Each of the two forms of corn accounted for 74.7% of the concentrate supplement, which was fed at 9 kg/d (DM) . The experiment was 13 wk, during which cows grazed permanent native pasture containing mostly grasses and some clover . Milk yield was 2.4 kg/d higher for cows fed ground high moisture shelled corn than for those fed dry cracked shelled corn . Milk fat content was lower (3.28 vs . 3.67%), but protein content was higher (3.26 vs . 3.15%) for the high moisture corn supplement . Results suggest that high moisture corn can serve as a better supplement for grazing cows than dry corn, likely by providing more metabolizable energy and microbial protein due to more fermentable and digestible starch.

J Dairy Sci, 2001 Oct, 84(10), 2203 - 16
Effects of grain processing, forage to concentrate ratio, and forage particle size on rumen pH and digestion by dairy cows; Yang WZ et al.; Dietary factors that alter the intake of effective fiber were evaluated for their effects on rumen fermentation, digestion, and milk production using a double 4 x 4 quasi-Latin square design with a 2(3) factorial arrangement of treatments . The dietary factors were extent of barley grain processing, coarse (1.60 mm) or flat (1.36 mm); forage-to-concentrate (F:C) ratio, low (35:65) or high (55:45) (dry matter basis); and forage particle length, long (7.59 mm) or short (6.08 mm) . Eight lactating cows with ruminal and duodenal cannulas were offered ad libitum access to a total mixed diet and milked twice daily . Dry matter intake was increased by increasing the extent of grain processing . Mean rumen pH was lower for cows fed flatly rolled barley than for cows fed coarsely rolled barley, whereas F:C ratio or forage particle size had no effect on rumen pH . Rumen pH was not correlated with effective NDF intake but tended to be correlated with digestibility of starch in the rumen . Total tract digestibilities of dry matter, organic matter, starch, and neutral detergent fiber were increased by feeding flatly rolled barley or low F:C ratio diets . Milk yield and milk protein content were higher in cows fed flatly rolled barley or low F:C ratio diets . Milk fat content tended to increase with high F:C ratio or long forage particle length but was reduced by feeding flatly rolled barley . In this study, extent of grain processing and intake of ruminal available starch were the most influential factors affecting milk production . Reducing the ratio of F:C improved total digestion and actual milk production . Forage particle length had minimal impact on digestibility and milk production.

Clin Podiatr Med Surg, 2001 Oct, 18(4), 555 - 684; discussion 685-90, v
Podiatric biomechanics . An historical appraisal and discussion of the Root model as a clinical system of approach in the present context of theoretical uncertainty; Lee WE; This article attempts to review comprehensively the development of the established Root Model and to appraise dispassionately its place and role in today's field of clinical podiatric biomechanics . It also discusses several important emergent models (the models of Dananberg, Kirby, Fuller, McPoil, Hunt, and Demp) that have gained increasing popularity among the podiatric and nonpodiatric clinical communities over the last 10 to 15 years . All of these models (the Root model and emergent models) have been analyses against the background of the Kuhnian concepts of "paradigm" and "preparadigm." Discussion has been provided as to whether the domain of podiatric biomechanics presently resides in a paradigm driven normal science phase, or whether it is still functioning within a preparadigm phase with its defining hallmark of community nonconsensus . Suggestions are then made as to possible ways for research to progress within the present ferment of debate and theoretic uncertainty.

J Bacteriol, 2001 Dec, 183(23), 6885 - 97
Ancestral divergence, genome diversification, and phylogeographic variation in subpopulations of sorbitol-negative, beta-glucuronidase-negative enterohemorrhagic Escherichia coli O157; Kim J et al.; The O157:H7 lineage of enterohemorrhagic Escherichia coli is a geographically disseminated complex of highly related genotypes that share common ancestry . The common clone that is found worldwide carries several markers of events in its evolution, including markers for acquisition of virulence genes and loss of physiological characteristics, such as sorbitol fermentation ability and beta-glucuronidase production . Populations of variants that are distinct with respect to motility and the sorbitol and beta-glucuronidase markers appear to have diverged at several points along the inferred evolutionary pathway . In addition to these variants, distinct subpopulations of the contemporary non-sorbitol-fermenting, beta-glucuronidase-negative O157:H7 clone were recently detected among bovine and human clinical isolates in the United States by using high-resolution genome comparison . In order to determine if these recently described subpopulations were derived from a regional or ancestral divergence event, we used octamer-based genome scanning, marker sorting, and DNA sequence analysis to examine their phylogenetic relationship to populations of non-sorbitol-fermenting, beta-glucuronidase negative O157:H7 and O157:H- strains from Australia . The inferred phylogeny is consistent with the hypothesis that subpopulations on each continent resulted from geographic spread of an ancestral divergence event and subsequent expansion of distinct subpopulations . Marker sorting and DNA sequence analyses identified sets of monophyletic markers consistent with the pattern of divergence and demonstrated that phylogeographic variation occurred through emergence of regional subclones and concentration of regional polymorphisms among distinct subpopulations . DNA sequence analysis of representative polyphyletic markers showed that genome diversity accrued through random drift and bacteriophage-mediated events.

J Nutr, 2001 Nov, 131(11 Suppl), 3041S - 6S
Short-chain fatty acids inhibit invasive human colon cancer by modulating uPA, TIMP-1, TIMP-2, mutant p53, Bcl-2, Bax, p21 and PCNA protein expression in an in vitro cell culture model; Emenaker NJ et al.; High intakes of dietary fiber or resistant starches have been associated with a lower incidence of colon cancers . Because short-chain fatty acids (SCFA) such as butyrate are produced in the colonic lumen by the bacterial fermentation of dietary fibers and resistant starches, we hypothesized that SCFA may inhibit the development of invasive human colon cancers . To test this hypothesis, primary human invasive colonocytes were isolated from fresh surgical specimens and treated with 0.01 mol/L acetate, propionate or butyrate; cell invasion, cell adhesion, F-actin polymerization, urokinase plasminogen activator (uPA), tissue inhibitor matrix metalloproteinase (TIMP)-1, TIMP-2 and mutant p53, Bcl-2, Bax, p21 and proliferating cell nuclear antigen (PCNA) protein expression levels were examined . Although each of the SCFA tested significantly reduced primary cell invasion, butyrate was the most potent, inhibiting primary invasive human colon cancer invasion by 54% (P < 0.0001) . The effects of SCFA on primary cell invasion appeared to be independent of cell adhesion and F-actin polymerization but dependent on the inhibition of uPA (P < 0.05) and the stimulation of TIMP-1 and TIMP-2 activities (P < 0.05) . Protein expression levels of mutant p53, p21, Bax, Bcl-2 and PCNA were significantly altered by each of the SCFA tested (P < 0.05) . These data indicate that SCFA inhibit invasive human colon cancer by modulating proteolytic uPA and antiproteolytic TIMP-1 and TIMP-2 activities, but their mechanisms of action on tumor suppression, apoptosis and growth arrest may differ.

Nutr Health, 2001, 15(2), 113 - 20
Development, acceptability and nutritional evaluation of 'Doli Ki Roti'--an indigenously fermented bread; Bhatia A et al.; 'Doli Ki Roti'-an indigenously fermented bread popular among the Indian Punjabi community who migrated from Pakistan during partition, is a wheat based product having spiced chickpea as stuffing . It contains a good blend of cereal and legume protein (14.5 to 17.1%), fat (7.3 to 9.2%) and ash (3.8 to 4.7%) . It is a good source of dietary essential minerals, i.e . calcium (52.7 to 62.6 mg/100 g), iron (8.7 to 10.6 mg/100 g) and phosphorus (313.8 to 346.7 mg/100 g) . The antinutrients like phytic acid and trypsin inhibitors are present in considerable amounts in the unfermented bread but are reduced to the extent of 5 to 18% (phytic acid) and 49 to 70% (trypsin inhibitors) due to the fermentation carried out at 35 and 40 degrees C for varying time periods . The products developed were organoleptically acceptable in terms of colour, taste, texture, flavour, etc.

Appl Biochem Biotechnol, 2001 Aug, 95(2), 103 - 12
Multipulse feed strategy for glycerol fed-batch fermentation: a steady-state nonlinear optimization approach; Xie D et al.; During glycerol fed-batch fermentation, the process could be divided into multiple equal subintervals, and the feed operation was performed in pulse form at the start of each subinterval . Based on the macrokinetic models, the multipulse feed strategy for both glucose and corn steep slurry was determined by a general nonlinear optimization approach to maximize the final glycerol productivity and still control the residual glucose at a low concentration . The experimental results in a 600-mL Airlift Loop Reactor showed that the tested data with this strategy agreed well with the corresponding model prediction, and that the feed mode with nonlinear optimization could improve the glycerol productivity significantly compared with those determined just by limited experimental optimization in previous studies.

Appl Microbiol Biotechnol, 2001 Oct, 57(1-2), 79 - 84
Optimization of stereoselective ketone reduction by the white-rot fungus Merulius tremellosus ono991; Hage A et al.; A recently isolated white-rot fungal strain, Merulius tremellosus ono991, displays high stereoselectivity during the reduction of arylketones . In order to increase the productivity and specific yield of the optically active alcohols, the culture conditions for the reduction of the model ketone compound 1'-acetonaphtone to alpha-methyl-1-naphtalenemethanol were optimized with respect to oxygen supply, choice of primary substrate and arylketone concentration . Alternative electron acceptors were also used to elucidate the role of reduction equivalents in the reduction process . The optimal yields of alpha-methyl-1-naphtalenemethanol were obtained in N2-flushed incubations with glycerol as primary substrate . The specific yield was increased from 57% to 98% compared to incubations under air with glucose . Most of the yield increase was due to N2-flushing and could be attributed to two factors . First, an increased stability of the product, alpha-methyl-1-naphtalenemethanol, in anaerobic compared to aerobic atmosphere was demonstrated . Second, fermentative metabolism increased reduced enzyme cofactors available for the reduction . Diverting reducing equivalents away from fermentation with alternative electron acceptors correlated with a decreased yield of alpha-methyl-1-naphtalenemethanol . Furthermore, the dependency of ketone reductase for common occurring metabolic reducing equivalents, NAD(P)H, was demonstrated by the reduction of 1'-acetonaphtone in cell extracts of M . tremellosus ono991.

Appl Microbiol Biotechnol, 2001 Oct, 57(1-2), 216 - 9
Production of a heterologous proteinase A by Saccharomyces kluyveri; Moller K et al.; In order to evaluate the potential of Saccharomyces kluyveri for heterologous protein production, S . kluyveri Y159 was transformed with a S . cerevisiae-based multi-copy plasmid containing the S . cerevisiae PEP4 gene, which encodes proteinase A, under the control of its native promoter . As a reference, S . cerevisiae CEN.PK 113-5D was transformed with the same plasmid and the two strains were characterised in batch cultivations on glucose . The glucose metabolism was found to be less fermentative in S . kluyveri than in S . cerevisiae . The yield of ethanol on glucose was 0.11 g/g in S . kluyveri, compared to a yield of 0.40 g/g in S . cerevisiae . Overexpression of PEP4 led to the secretion of active proteinase A in both S . kluyveri and S . cerevisiae . The yield of active proteinase A during growth on glucose was found to be 3.6-fold higher in S . kluyveri than in the S . cerevisiae reference strain.

Appl Microbiol Biotechnol, 2001 Oct, 57(1-2), 205 - 11
Nitrogen-removal with protease as a method to improve the selective delignification of hemp stemwood by the white-rot fungus Bjerkandera sp . strain BOS55; Dorado J et al.; Certain white-rot fungi cause selective removal of lignin from woody substrates . Selective delignification can potentially be applied to biopulping and upgrading animal feeds . Nitrogen nutrient limitation is known to enhance the selectivity of lignin degradation . The relatively high N-content of annual fiber crops is an important drawback for utilizing white-rot fungi for their selective delignification . In this study, removal of N from hemp stemwood with protease was explored as a means of improving the selectivity of lignin degradation by the white-rot fungus Bjerkandera sp . strain BOS55 . Various protease treatments followed by hot-water extraction were found to be suitable in lowering the N-content of hemp stemwood by up to 70% . The removal was significantly higher than with hot-water extraction alone, which caused a 39% N-removal . The selectivity of lignin degradation was compared in protease-treated, hot-water treated, untreated and ammonium-spiked hemp stemwood, providing N levels that were, respectively, 0.32-, 0.61-, 1.0- and 5.0-fold relative to the natural N-content in the substrate . Removal of N by hot-water extraction alone or in combination with protease greatly protected the holocellulose fraction from excessive decay during 10 weeks of solid state fermentation . However, the selectivity of lignin decay was only greatly enhanced (three-fold) by the protease treatment, due mostly to a highly improved lignin degradation at the lowest N-level.

Appl Microbiol Biotechnol, 2001 Oct, 57(1-2), 192 - 9
Aflatoxin genes and the aflatoxigenic potential of Koji moulds; van den Broek P et al.; Sixty-four Aspergillus isolates, 54 of which originated from food fermentations, and 18 Aspergillus reference strains were identified and screened for the presence of aflatoxin genes aflR and omt-1 . Among the Koji moulds, not only A . oryzae but also A . flavus strains were found . Furthermore, 27% of A . oryzae and 93% of A . flavus strains lacked either aflR or both aflR- and omt-1 . A selection of 29 strains was also checked for the presence of pksA and nor-1 . This revealed large deletions in the aflatoxin gene cluster of some strains . The hybridisation patterns also suggested a polarity in the deletion events, originating in the vicinity of pksA and extending towards omt-1 . Other strains exhibited BamHI restriction fragment length polymorphisms (RFLPs) for either aflR or for aflR and omt-1 . All aflR and/or omt-1 deletion strains turned out to be unable to produce aflatoxin . The RFLP-carrying strains either produced only traces of aflatoxin or none at all . In 73% of the A . oryzae strains, no apparent deletions were detected with the aflR and omt-1 probes . Nevertheless, after incubation in aflatoxin-inducing media, no aflatoxin B1 production could be detected in those A . oryzae strains.

Appl Microbiol Biotechnol, 2001 Oct, 57(1-2), 186 - 91
Characterization of sugar mixtures utilization by an Escherichia coli mutant devoid of the phosphotransferase system; Hernandez-Montalvo V et al.; Due to catabolite repression in microorganisms, sugar mixtures cannot be metabolized in a rapid and efficient manner . Therefore, the development of mutant strains that avoid this regulatory system is of special interest to fermentation processes . In the present study, the utilization of sugar mixtures by an Escherichia coli mutant strain devoid of the phosphotransferase system (PTS) was characterized . This mutant can transport glucose (PTS- Glucose+ phenotype) by a non-PTS mechanism as rapidly as its wild-type parental strain . In cultures grown in minimal medium supplemented with glucose-xylose or glucose-arabinose mixtures, glucose repressed arabinose- or xylose-utilization in the wild-type strain . However, under the same culture conditions with the PTS- Glucose+ mutant, glucose and arabinose were co-metabolized, but glucose still exerted a partial repressive effect on xylose consumption . In cultures growing with a triple mixture of glucose-arabinose-xylose, the wild-type strain sequentially utilized glucose, arabinose and finally, xylose . In contrast, the PTS- Glucose+ strain co-metabolized glucose and arabinose, whereas xylose was utilized after glucose-arabinose depletion . As a result of glucose-arabinose co-metabolism, the PTS- Glucose+ strain consumed the total amount of sugars contained in the culture medium 16% faster than the wild-type strain . {14C}-Xylose uptake experiments showed that in the PTS- Glucose+ strain, galactose permease increases xylose transport capacity and the observed partial repression of xylose utilization depends on the presence of intracellular glucose.

Appl Microbiol Biotechnol, 2001 Oct, 57(1-2), 167 - 74
Effect of overexpression of Saccharomyces cerevisiae Pad1p on the resistance to phenylacrylic acids and lignocellulose hydrolysates under aerobic and oxygen-limited conditions; Larsson S et al.; Lignocellulose hydrolysates, obtained by acid hydrolysis for production of bioethanol, contain, in addition to fermentable sugars, compounds that inhibit the fermenting micro-organism . One approach to alleviate the inhibition problem is to use genetic engineering to introduce increased tolerance . Phenylacrylic acid decarboxylase (Pad1p) catalyses a decarboxylation step, by which aromatic carboxylic acids are converted to the corresponding vinyl derivatives . Pad1p-overexpressing Saccharomyces cerevisiae was cultivated in synthetic medium in the presence of model compounds, ferulic acid {(2 E)-3-(4-hydroxy-3-methoxyphenyl)prop-2-enoic acid} and cinnamic acid {(2 E)-3-phenylprop-2-enoic acid}, as well as in a dilute acid hydrolysate of spruce to examine the resistance against fermentation inhibitors . Overexpression of S . cerevisiae phenylacrylic acid decarboxylase (Pad1p) resulted in an improved growth rate and ethanol productivity in the presence of ferulic acid, cinnamic acid, and in a dilute acid hydrolysate of spruce . Vinyl guaiacol (2-methoxy-4-vinylphenol) was identified as a major metabolite of ferulic acid, and dihydroferulic acid {3-(4-hydroxy-3-methoxyphenyl)propanoic acid} was detected under oxygen-limited conditions . Styrene (vinylbenzene) and dihydrocinnamic acid (3-phenylpropanoic acid) were identified as metabolites of cinnamic acid . Transformants overexpressing Pad1p had the ability to convert ferulic and cinnamic acid at a faster rate than a control transformant (PAD(C)) not overexpressing Pad1p . This enabled faster growth for Pad1p-overexpressing transformants under both aerobic and oxygen-limited conditions . Pad1p activity was also studied using non-growing cells . The overexpressing transformants showed approximately tenfold higher activity than PAD(C) . The Pad1p overexpressing transformants also showed a 22-25% faster glucose consumption rate, a 40-45% faster mannose consumption rate, and a 24-29% faster ethanol production rate in the dilute acid hydrolysate of spruce.

Analyst, 2001 Oct, 126(10), 1733 - 9
Peroxidase enzyme sensor for on-line monitoring of disinfection processes in the food industry; Moody A et al.; For desirable environmental reasons, peroxides have replaced halogenated substances for disinfection purposes in the food and beverage industry . However, cost issues and the requirement to remove these agents completely after disinfection necessitate simple, low-cost and sensitive test methods with a wide dynamic range and on-line capability . The development and performance of such a method is detailed here . Low-cost peroxide sensors were fabricated using a single deposition procedure, in which horseradish peroxidase enzyme and dimethylferrocene mediator were entrapped within a cellulose acetate membrane, over the working electrode area of a screen-printed three-electrode assembly . Optimum performance was obtained using HRP and DMFc loadings of 25 U and 0.03 micromol per electrode, respectively, and a mean cellulose acetate molecular weight of 37,000 . The device had a detection limit of 49.5 microM hydrogen peroxide and mean RSD values of 21% across the concentration range 49.5-368 microM . In laboratory studies the sensor was shown to have a stability of > or = 4 d in continuous flow-mode maintaining an accuracy of +/- 16% that was considered acceptable for the intended on-line monitoring of the disinfection process . In a field study, it was successfully used on-line within a flow-cell to measure peroxide levels during disinfection of an industrial fermentation vessel.

Fresenius J Anal Chem, 2001 Oct, 371(3), 380 - 4
Separation, identification, and quantification of amino acids in L-lysine fermentation potato juices by gas chromatography-mass spectrometry; Starke I et al.; The amino acid composition of L-lysine fermentation juices from potatoes and cane molasses from a green biorefinery has been determined by gas chromatography-mass spectrometry . N-Methyl-N-tert(butyldimethylsilyl)tri-fluoroacetamide (MTBSTFA) was used as derivatization reagent to prepare the t-butyldimethylsilyl derivatives of the amino acids present in the juices . The amino acids in these derivatives were identified from both their EI and CI mass spectra and their retention times in the gas chromatogram, and they were quantified employing the GC response signals relative to cycloleucine as internal standard.

J Ind Microbiol Biotechnol, 2001 Oct, 27(4), 252 - 8
A moderate amplification of the mecB gene encoding cystathionine-gamma-lyase stimulates cephalosporin biosynthesis in Acremonium chrysogenum; Kosalkova K et al.; L-cysteine is a precursor of the penicillin, cephalosporin and cephamycin families of beta-lactam antibiotics . Cystathionine-gamma-lyase (encoded by the mecB gene), an enzyme that splits cystathionine releasing cysteine, is required for high-level cephalosporin production in methionine-supplemented medium . By amplification of the mecB gene in Acremonium chrysogenum C10, several transformants were obtained that produced 10-40% higher levels of cephalosporin . All selected transformants contained at least two or three copies of the mecB gene as shown by Southern hybridization with a probe internal to mecB . Two of these transformants, A . chrysogenum T27 and A . chrysogenum T58, showed 4- to 10-fold higher cystathionine-gamma-lyase activity than the control strain . Northern hybridizations indicated that the levels of the two mecB transcripts of 1.7 and 1.5 kb were greatly increased in transformants T27 and T58 . Fermentor studies using controlled conditions confirmed that transformant T27 was a cephalosporin overproducer, reaching titers of nearly 2000 microg/ml of cephalosporin in Shen-defined medium that correlated with two- to fourfold higher cystathionine-gamma-lyase levels than in the control strain . Transformant T58 containing five- to sixfold higher levels of cystathionine-gamma-lyase in fermentor cultures showed a reduced growth rate and a slow cephalosporin accumulation rate . In conclusion, moderately increased levels of cystathionine-gamma-lyase stimulated cephalosporin production but very high levels of this enzyme were deleterious for growth and cephalosporin biosynthesis.

J Ind Microbiol Biotechnol, 2001 Oct, 27(4), 199 - 202
Eicosapentaenoic and docosahexaenoic acids production by and okara-utilizing potential of thraustochytrids; Fan KW et al.; Nine thraustochytrid strains isolated from subtropical mangroves were screened for their eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) production potential in a glucose yeast extract medium . Their ability to utilize okara (soymilk residue) for growth and EPA and DHA production was also evaluated . EPA yield was low in most strains, while DHA level was high on glucose yeast extract medium, producing 28.1-41.1% of total fatty acids, for all strains, with the exception of Ulkenia sp . KF13 . The DHA yield of Schizochytrium mangrovei strains ranged from 747.7 to 2778.9 mg/l after 52 h of fermentation at 25 degrees C . All strains utilized okara as a substrate for growth, but DHA yield was lower when compared with fermentation in a glucose yeast extract medium.

J Anim Physiol Anim Nutr (Berl), 2001 Jun, 85(5-6), 124 - 34
Fermentation of liquid coproducts and liquid compound diets: Part 2 . Effects on pH, acid-binding capacity, organic acids and ethanol during a 6-day storage period; Scholten RH et al.; The effects of a 6-day storage period on changes in pH, acid-binding capacity, level of organic acids and ethanol of three liquid coproducts {liquid wheat starch (LWS), mashed potato steam peel (PSP) and cheese whey (CW)} and two liquid compound diets {liquid grower diet (LGD) and liquid finisher diet (LFD)} were studied . All products, except LWS, showed a significant decrease in pH and acid-binding capacity during storage . At the end of the storage period, all products reached a pH of between 3.5 and 3.9 . In general, it can be concluded that the lactic acid content, and to a lesser extent the acetic acid content, increased dramatically during storage . In contrast, the ethanol content increased significantly in the liquid compound diets only . The pattern of changes in pH and organic acids during the 6-day storage period was different between the liquid coproducts and the liquid compound diets . At the start of storage, liquid coproducts are already in the 'middle' of the fermentation process, while liquid compound diets need approximately 24-36 h before fermentation begins . Consequently, in practice a different approach to obtain fermented diets is needed for liquid coproducts and liquid compound diets.

J Anim Physiol Anim Nutr (Berl), 2001 Jun, 85(5-6), 111 - 23
Fermentation of liquid coproducts and liquid compound diets: Part 1 . Effects on chemical composition during a 6-day storage period; Scholten RH et al.; The effects of a 6-day storage period on changes in dry matter, crude ash, crude protein, true protein, crude fat, starch, soluble starch, sugar and lactose of three liquid coproducts and two liquid compound diets were studied . The three liquid coproducts studied were: liquid wheat starch (LWS), mashed potato steam peel (PSP) and cheese whey (CW), and the two liquid compound diets were: liquid grower diet (LGD) and liquid finisher diet (LFD) . The loss of corrected dry matter after a 6-day storage, expressed in relation to the initial content, was 1.9, 6.2, 9.6, 4.6 and 4.2% for LWS, PSP, CW, LGD and LFD, respectively . During storage, the total amount of starch decreased 2.7, 24.0, 28.1 and 33.3% for LWS, PSP, LGD and LFD, respectively . The total amount of lactose decreased 23.5% for CW . The gross energy value of the products did not change remarkably during the 6-day storage period; gross energy losses being less than 3% of the initial gross energy content.

J Am Chem Soc, 2001 Nov 7, 123(44), 10927 - 34
Benzene-free synthesis of hydroquinone; Ran N et al.; All current routes for the synthesis of hydroquinone utilize benzene as the starting material . An alternate route to hydroquinone has now been elaborated from glucose . While benzene is a volatile carcinogen derived from nonrenewable fossil fuel feedstocks, glucose is nonvolatile, nontoxic, and derived from renewable plant polysacharrides . Glucose is first converted into quinic acid using microbial catalysis . Quinic acid is then chemically converted into hydroquinone . Under fermentor-controlled conditions, Escherichia coli QP1.1/pKD12.138 synthesizes 49 g/L of quinic acid from glucose in 20% (mol/mol) yield . Oxidative decarboxylation of quinic acid in clarified, decolorized, ammonium ion-free fermentation broth with NaOCl and subsequent dehydration of the intermediate 3(R),5(R)-trihydroxycyclohexanone afforded purified hydroquinone in 87% yield . Halide-free, oxidative decarboxylation of quinic acid in fermentation broth with stoichiometric quantities of (NH(4))(2)Ce(SO(4))(3) and V(2)O(5) afforded hydroquinone in 91% and 85% yield, respectively . Conditions suitable for oxidative decarboxylation of quinic acid with catalytic amounts of metal oxidant were also identified . Ag(3)PO(4) at 2 mol % relative to quinic acid in fermentation broth catalyzed the formation of hydroquinone in 74% yield with K(2)S(2)O(8) serving as the cooxidant . Beyond establishing a fundamentally new route to an important chemical building block, oxidation of microbe-synthesized quinic acid provides an example of how the toxicity of aromatics toward microbes can be circumvented by interfacing chemical catalysis with biocatalysis.

Can J Microbiol, 2001 Sep, 47(9), 829 - 41
Comparative denaturing gradient gel electrophoresis analysis of fungal communities associated with whole plant corn silage; May LA et al.; Significant portions of grain produced for livestock consumption are convened into ensiled forage . Silage producers have long recognized the positive effects of using an inoculant to insure the proper transformation of forage into a palatable and digestible feedstuff . When silage is fed from a storage structure, exposure to air stimulates the growth of epiphytic aerobes that may result in the loss of up to 50% of the dry matter . Moreover, fungi have been found to be associated with ensiled forage, but their growth is normally suppressed by the anaerobic conditions . However, the introduction of oxygen results in a fungal bloom, and the fungi and the associated metabolites may result in lost productivity in the livestock consuming the contaminated forage . In this study, we report on the diversity of the fungal community associated with whole plant corn silage during the ensiling process, and the effect of two different bacterial inoculants as compared with the uninoculated natural epiphytic fermentation on the distribution of the fungi associated with the silage . The fungal community from duplicate mini-silo packages of the same treatment was analyzed by denaturing gradient gel electrophoresis and direct sequencing of the resulting operational taxonomic units . This method proved useful in analyzing the complex microbial communities associated with the forage in that it was possible to determine that one inoculant dramatically influenced the fungal community associated with whole plant corn silage.

Can J Microbiol, 2001 Sep, 47(9), 801 - 6
Analysis of the relationship between growth, cephalosporin C production, and fragmentation in Acremonium chrysogenum; Sandor E et al.; Mycelial fragmentation in submerged cultures of the cephalosporin C (CPC) producing fungus Acremonium chrysogenum was characterized by image analysis . In both fed-batch and chemostat cultures, the proportion of mycelial clumps seemed to be the most sensitive morphological indicator of fragmentation . In a fed-batch fermentation culture, this declined from roughly 60% at inoculation to less than 10% after 43 h . Subsequent additions of glucose resulted in a sharp increase back to near the initial value, an increase that reversed itself a few hours after glucose exhaustion . Meanwhile CPC production continued to decline steadily . On the other hand, the addition of soybean oil enhanced CPC production, but had no significant effect on the morphology . Although it may sometimes appear that morphology and productivity are related in batch or fed-batch cultures, this study suggests that this is because both respond simultaneously to more fundamental physiological changes, dependent on the availability of carbon . In circumstances, such as supplementary carbon source addition, the relationship is lost . Chemostat cultures supported this belief, as CPC-production rates were hardly affected by the specific growth rate, but the morphology showed significant differences, i.e., lower dilution rates resulted in a lower proportion of clumps and in smaller clumps.

Mol Genet Genomics, 2001 Oct, 266(2), 246 - 53
A defined level of protein disulfide isomerase expression is required for optimal secretion of thaumatin by Aspegillus awamori; Moralejo FJ et al.; Thaumatin, a 22-kDa protein containing eight disulfide bonds, is secreted by the filamentous fungus Aspergillus awamori at levels which are dependent upon the extent of overexpression of protein disulfide isomerase (PDIA) . Additional copies of the PDIA-encoding gene pdiA were introduced into a strain of A . awamori that expresses a cassette encoding thaumatin . Transformants with different levels of pdiA mRNA and measured PDIA levels were chosen for examination of the impact that PDIA levels had on thaumatin secretion . The secretion of two native proteins, alpha-amylase and acid phosphatase, was also examined in relation to varying levels of PDIA . Over a range of PDIA levels of 1-8, relative to the native level in strains with just one copy of the pdiA gene, the fraction of alpha-amylase and acid phosphatase in the total secreted protein was unaffected . In contrast, a peak level of thaumatin, about 5-fold higher than in the strain with one copy of pdiA, was found in strains with a relative PDIA level of between two and four . Improved thaumatin production was confirmed in 5-1 fermenters using a strain of A . awamori with six pdiA gene copies, containing 3.2-fold higher levels of PDIA than wild-type strains.

J Clin Microbiol, 2001 Nov, 39(11), 3955 - 61
Phenotypic identification of Actinomyces and related species isolated from human sources; Sarkonen N et al.; Recent advancements in chemotaxonomic and molecular biology-based identification methods have clarified the taxonomy of the genus Actinomyces and have led to the recognition of several new Actinomyces and related species . Actinomyces-like gram-positive rods have increasingly been isolated from various clinical specimens . Thus, an easily accessible scheme for reliable differentiation at the species level is needed in clinical and oral microbiology laboratories, where bacterial identification is mainly based on conventional biochemical methods . In the present study we designed a two-step protocol that consists of a flowchart that describes rapid, cost-efficient tests for preliminary identification of Actinomyces and closely related species and an updated more comprehensive scheme that also uses fermentation reactions for accurate differentiation of Actinomyces and closely related species.

FEMS Microbiol Lett, 2001 Oct 16, 204(1), 61 - 4
K+ influx by Kup in Escherichia coli is accompanied by a decrease in H+ efflux; Zakharyan E et al.; Escherichia coli accumulates K+ by means of multiple uptake systems of which Kup is the major transport system at acidic pH . In cells grown under fermentative conditions at pH 5.5, K+ influx by a wild-type strain upon hyper-osmotic stress at pH 5.5 was accompanied by a marked decrease in H+ efflux, with a 1:1 ratio of K+ to H+ fluxes . This was observed with cells treated with N,N'-dicyclohexylcarbodiimide . Similar results with a mutant defective in Kdp and TrkA but with a functional Kup system but not in a mutant defective in Kdp and Kup but having an active TrkA system suggest that Kup operates as a H+ -K+ -symporter.

Mol Cell Biochem, 2001 Jul, 223(1-2), 131 - 7
Stimulatory effect of menaquinone-7 (vitamin K2) on osteoblastic bone formation in vitro; Yamaguchi M et al.; Menaquinone-7, which is vitamin K2 (menatetrenone) with seven isoprene units, is highly contained in the fermented soybean . The effect of menaquinone-7 (MK-7) on osteoblastic bone formation was investigated . Femoral-diaphyseal and metaphyseal tissues of young male rats (4 weeks old) were cultured for 48 h in a medium containing either vehicle or MK-7 (10(-7)-10(-5) M) . Calcium content, alkaline phosphatase activity, and deoxyribonuclic acid (DNA) content in the diaphyseal and metaphyseal tissues was significantly increased in the presence of MK-7 (10(-6) and 10(-5) M) . The effect of MK-7 in increasing the diaphyseal and metaphyseal calcium content and alkaline phosphatase activity was completely prevented in the presence of cycloheximide (10(-6) M), an inhibitor of protein synthesis . Moreover, osteoblastic MC3T3-E1 cells after subculture were cultured for 24 h in a serum-free medium containing MK-7 (10(-7)-10(-5) M) . Protein content, alkaline phophatase activity, osteocalcin and DNA content in the cells was significantly increased in the presence of MK-7 (10(-6) and 10(-5) M) . The effect of MK-7 in increasing protein content, alkaline phosphatase activity, and osteocalcin production in the cells was completely blocked by cycloheximide . This study demonstrates that MK-7 has an anabolic effect on bone tissue and osteoblastic MC3T3-E1 cells in vitro, suggesting that the compound can stimulate osteoblastic bone formation.

Rev Med Brux, 2001 Sep, 22(4), A285 - 8
{Dental pain}; Vermeire P; "The extreme variability of toothache is such that a good rule for any examiner is to consider all pains about the mouth and face to be of dental origin until provide otherwise" (Welden E . Bell) . Dental caries is a disease of the calcified tissues of the teeth, characterised by demineralization of the inorganic portion and destruction of the organic substance of the tooth . The acids which affects the primary decalcifications is derived from the fermentation of starches and sugar logged in the retaining centers of the teeth . Dental caries can be classified in relation with the depth of the lesions: caries of the enamel, caries of the dentin, pulp diseases which are the result of dental caries in which bacterial invasion of the dentin and pulp tissue occurs, diseases of the periapical tissues which leads to periapical cyst, or to periapical abcess.

Biosens Bioelectron, 2001 Dec, 16(9-12), 765 - 71
Monitoring of alpha-ketoglutarate in a fermentation process using expanded bed enzyme reactors; Collins A et al.; A bienzyme flow injection system is presented for the monitoring of alpha-ketoglutarate produced in a fermentation process, using glutamate dehydrogenase (GDH) and glutamate oxidase (GlOx) immobilised in two serially connected expanded bed reactors . The use of expanded bed resulted in unhindered passage of the bacterial cells through the columns, and thereby the need of a separate filtering step (e.g . microdialysis) was avoided . In the first reactor, alpha-ketoglutarate was converted to L-glutamate by GDH in the presence of ammonia and NADH . In the following reactor, L-glutamate was converted by GlOx to alpha-ketoglutarate, ammonia and hydrogen peroxide, which was detected in an electrochemical flow-through cell at +650 mV vs . Pt/(0.1 M KCl) . The detection limit of alpha-ketoglutarate in the coupled packed bed reactors was 1 microM (defined as 3 S/N), the linear range 0-100 microM, and the sensitivity 0.80 nA/microM (R(2) 0.99) . In the coupled expanded bed reactors, the detection limit of alpha-ketoglutarate was 7 microM (defined as 3 S/N), the linear range and the sensitivity being 0-500 microM and 0.11 nA/microM (R(2) 1.00), respectively . The response time (defined as the time between peak rise and return to baseline) was 5 min for coupled packed beds (injection of supernatant), and 12 min for coupled expanded beds (injection of sample containing cellular and particulate matter) . Several other parameters, such as reactor stability, flow rate dependency, bed expansion, glutamate interference, etc . were investigated and characterised . When analysing real samples from a fermentation broth, the same results were obtained independent of the nature of the reactor system (packed or expanded bed) . The hereby described system can easily be automatised and controlled from a personal computer.

Org Lett, 2001 Nov 1, 3(22), 3479 - 81
The structure of microcarpalide, a microfilament disrupting agent from an endophytic fungus; Ratnayake AS et al.; {structure: see text} . A new alkyl-substituted nonenolide, microcarpalide 1, has been isolated from fermentation broths of an unidentified endophytic fungus . Microcarpalide is weakly cytotoxic to mammalian cells and acts as a microfilament disrupting agent . The structure of 1 was elucidated by application of spectroscopic methods . The absolute configuration was determined by the exciton chirality method.

Plant Foods Hum Nutr, 2001, 56(4), 365 - 84
Evaluation of pumpkin seed products for bread fortification; El-Soukkary FA; Pumpkin seed products (raw, roasted, autoclaved, germinated, fermented, pumpkin protein concentrate and pumpkin protein isolate) were incorporated into wheat flour to produce blends with protein levels of 15, 17, 19 and 21% . Dough properties were evaluated by a farinograph; loaves of breads were evaluated by a taste panel for crust color, crumb color, crumb texture, flavor, and overall quality . Results indicated that pumpkin seed products can be added to wheat flour up to a 17% protein level for raw, roasted and autoclaved pumpkin meal, 19% level for germinated, fermented and pumpkin protein concentrate and 21% level for pumpkin protein isolate without a detrimental effect on dough or loaf quality . On the other hand, the addition of pumpkin seed proteins resulted in increasing protein, lysine and mineral contents compared to the control . While lysine and tryptophan were the first and second limiting amino acids in the control bread, tryptophan and lysine were the first and second limiting amino acids for raw, roasted, autoclaved, germinated and fermented pumpkin meal; valine and lysine and valine and total sulfur amino acids were the first and second limiting amino acids for pumpkin protein concentrate and isolate, respectively . In vitro protein digestibility improved when the pumpkin seed proteins were added.

Arch Latinoam Nutr, 2001 Jun, 51(2), 199 - 203
{Effect of iron salts addition on the sensory characteristics of soy yogurt}; Umbelino DC et al.; The soy-yogurt was used as food vehicle due to its therapeutic and nutritional properties and lower cost . The aim of this work was to develop an enriched soy-yogurt with 12 mg of elementary iron/l, with suitable sensory and technological properties . Four iron sources were tested: FeSO4.7H2O, NaFeEDTA, Ferrochel and microencapsulated FeSO4.7H2O . The products were evaluated by fermentation time, pH, titratable acidity, viscosity, consistency, iron concentration and sensory properties (difference from the control and acceptance tests) . Viscosity and consistency data were submitted to analysis of variance and Tukey's test . Difference from the control data was evaluated by analysis of variance and Dunnett's test and the acceptance test was evaluated by analysis of variance and Tukey's test . For all iron salts used in the enrichment process, only the FeSO4.7H2O did not work out because of the undesirable sensorial characteristics of the final products . The others sources used in the enrichment process (NaFeEDTA, Ferrochel and microencapsulated FeSO4.7H2O) did not alter the fermentation time, titratable acidity and sensory and reologics properties of the soy-yogurt.

Protein Expr Purif, 2001 Nov, 23(2), 233 - 41
Expression analysis of a modified factor X in stably transformed insect cell lines; Pfeifer TA et al.; A modified Factor X protein was combined with a cellulose-binding domain tag and expressed in insect cell lines . The protein, CBDFX, was expressed and secreted into the medium . Stable, transformed Hi5 and Sf9 insect cell lines were generated and tested for production of secreted CBDFX . The highest Sf9 and Hi5 CBDFX-producing cell lines were scaled up to 2-liter fermentors to evaluate production of this recombinant protein . Secreted protein production levels reached 4 mg/liter for the stable, transformed Hi5 cell line and 18 mg/liter for the stable, transformed Sf9 cell line . The protein was properly processed as determined by amino terminal sequencing and bound well to the cellulose substrate Avicel . In addition the activated recombinant CBDFX(a) was capable of recognizing and efficiently processing a Factor X cleavage site .

Metab Eng, 2001 Oct, 3(4), 301 - 12
Glycerol export and glycerol-3-phosphate dehydrogenase, but not glycerol phosphatase, are rate limiting for glycerol production in Saccharomyces cerevisiae; Remize F et al.; Glycerol, one of the most important by-products of alcoholic fermentation, has positive effects on the sensory properties of fermented beverages . It was recently shown that the most direct approach for increasing glycerol formation is to overexpress GPD1, which encodes the glycerol-3-phosphate dehydrogenase (GPDH) isoform Gpd1p . We aimed to identify other steps in glycerol synthesis or transport that limit glycerol flux during glucose fermentation . We showed that the overexpression of GPD2, encoding the other isoform of glycerol-3-phosphate dehydrogenase (Gpd2p), is equally as effective as the overexpression of GPD1 in increasing glycerol production (3.3-fold increase compared to the wild-type strain) and has similar effects on yeast metabolism . In contrast, overexpression of GPP1, encoding glycerol 3-phosphatase (Gpp1p), did not enhance glycerol production . Strains that simultaneously overexpress GPD1 and GPP1 did not produce higher amounts of glycerol than a GPD1-overexpressing strain . These results demonstrate that GPDH, but not the glycerol 3-phosphatase, is rate-limiting for glycerol production . The channel protein Fps1p mediates glycerol export . It has recently been shown that mutants lacking a region in the N-terminal domain of Fps1p constitutively release glycerol . We showed that cells producing truncated Fps1p constructs during glucose fermentation compensate for glycerol loss by increasing glycerol production . Interestingly, the strain with a deregulated Fps1 glycerol channel had a different phenotype to the strain overexpressing GPD genes and showed poor growth during fermentation . Overexpression of GPD1 in this strain increased the amount of glycerol produced but led to a pronounced growth defect .

Gene, 2001 Aug 22, 274(1-2), 111 - 8
proBA complementation of an auxotrophic E . coli strain improves plasmid stability and expression yield during fermenter production of a recombinant antibody fragment; Fiedler M et al.; The proline-auxotrophic Escherichia coli K12 strain JM83 harbouring an expression vector providing the proBA gene in trans was utilized for the fermenter production of the partially humanized IN-1 antibody F(ab) fragment . Thus, plasmid-mediated complementation of the chromosomal proBA deletion was employed as a second selection mechanism, together with a chloramphenicol resistance, in order to (i) abolish plasmid loss and (ii) benefit from E . coli JM83 as an expression strain with approved periplasmic protein secretion characteristics in the presence of a minimal medium . Starting from the generic vector pASK75, which makes use of the tightly regulated and chemically inducible tet promoter for foreign gene expression, a set of new vectors carrying the entire or part of the proBA operon was constructed and compared concerning their capability of functional Delta proBA complementation as well as recombinant protein yield . As a result, the vector pMF1 was developed, where transcription of the proBA operon is controlled by its own constitutive promoter and terminator sequences, permitting the transformed JM83 strain to grow under glucose/ammonia minimal culture conditions . When pMF1 was used for the fermenter production of the IN-1 F(ab) fragment, no plasmid loss was observed during the growth and induction phases, and the yield of functionally purified recombinant protein was found to be considerably improved.

Phytochemistry, 2001 Nov, 58(5), 751 - 8
Phytotoxic naphthopyranone derivatives from the coprophilous fungus Guanomyces polythrix; Macias M et al.; Reinvestigation of the fermentation broth and mycelium of the coprophilous fungus Guanomyces polythrix, grown in static conditions, led to the isolation of several phytotoxic compounds, including two new naphthopyranone derivatives, namely (2S, 3R)-5-hydroxy-6,8-dimethoxy-2,3-dimethyl-2,3-dihydro-4H-naphtho{2,3-b}-pyran-4-one and (2S, 3R)-5-hydroxy-6,8,10-trimethoxy-2,3-dimethyl-2,3-dihydro-4H-naphtho{2,3-b}-pyran-4-one . The structures of the new compounds were established by spectral and chiroptical methods . In addition, the structure of 8-hydroxy-6-methyl-9-oxo-9H-xanthene-1-carboxylic acid methyl ester was unambiguously determined by X-ray analysis . The isolates caused significant inhibition of radicle growth of two weed seedlings (Amaranthus hypochondriacus and Echinochloa crusgalli) and interacted with both spinach and bovine brain calmodulins.

Phytochemistry, 2001 Nov, 58(5), 709 - 16
Biosynthesis of ochratoxins by Aspergillus ochraceus; Harris JP et al.; Shaken liquid fermentation of an isolate of Aspergillus ochraceus showed growth-associated production of ochratoxins A and B, followed by production of a related polyketide diaporthin . Later, between 150 and 250 h, mellein accumulated transitorily . In contrast, shaken solid substrate (shredded wheat) fermentation over 14 days produced mainly ochratoxins A and B (ratio ca . 5:1) in very high yield (up to 10 mg/g) . In these systems experiments with 14C-labelled precursors and putative intermediates revealed temporal separation of early and late stages of the ochratoxin biosynthetic pathway, but did not support an intermediary role for mellein . The pentaketide intermediate ochratoxin beta was biotransformed very efficiently into both ochratoxins A and B, 14 and 19%, respectively . The already chlorinated ochratoxin alpha was only biotransformed significantly (4.85%) into ochratoxin A, indicating that chlorination is mainly a penultimate biosynthetic step in the biosynthesis of ochratoxin A . This was supported by poor (1.5%) conversion of radiolabelled ochratoxin B into ochratoxin A . Experiments implied that some ochratoxin B may arise by dechlorination of ochratoxin A.

Biosens Bioelectron, 2001 Aug, 16(6), 337 - 53
Microbial biosensors; D'Souza SF; A microbial biosensor consists of a transducer in conjunction with immobilised viable or non-viable microbial cells . Non-viable cells obtained after permeabilisation or whole cells containing periplasmic enzymes have mostly been used as an economical substitute for enzymes . Viable cells make use of the respiratory and metabolic functions of the cell, the analyte to be monitored being either a substrate or an inhibitor of these processes . Bioluminescence-based microbial biosensors have also been developed using genetically engineered microorganisms constructed by fusing the lux gene with an inducible gene promoter for toxicity and bioavailability testing . In this review, some of the recent trends in microbial biosensors with reference to the advantages and limitations are been discussed . Some of the recent applications of microbial biosensors in environmental monitoring and for use in food, fermentation and allied fields have been reviewed . Prospective future microbial biosensor designs have also been identified.

Biochem J, 2001 Nov 1, 359(Pt 3), 517 - 23
PtdIns(4,5)P(2) and phospholipase C-independent Ins(1,4,5)P(3) signals induced by a nitrogen source in nitrogen-starved yeast cells; Bergsma JC et al.; Addition of ammonium sulphate to nitrogen-depleted yeast cells resulted in a transient increase in Ins(1,4,5)P(3), with a maximum concentration reached after 7-8 min, as determined by radioligand assay and confirmed by chromatography . Surprisingly, the transient increase in Ins(1,4,5)P(3) did not trigger an increase in the concentration of intracellular calcium, as determined in vivo using the aequorin method . Similar Ins(1,4,5)P(3) signals were also observed in wild-type cells treated with the phospholipase C inhibitor 3-nitrocoumarin and in cells deleted for the only phospholipase C-encoding gene in yeast, PLC1 . This showed clearly that Ins(1,4,5)P(3) was not generated by phospholipase C-dependent cleavage of PtdIns(4,5)P(2) . Apart from a transient increase in Ins(1,4,5)P(3), we observed a transient increase in PtdIns(4,5)P(2) after the addition of a nitrogen source to nitrogen-starved glucose-repressed cells . Inhibition by wortmannin of the phosphatidylinositol 4-kinase, Stt4, which is involved in PtdIns(4,5)P(2) formation, did not affect the Ins(1,4,5)P(3) signal, but significantly delayed the PtdIns(4,5)P(2) signal . Moreover, wortmannin addition inhibited the nitrogen-induced activation of trehalase and the subsequent mobilization of trehalose, suggesting a role for PtdIns(4,5)P(2) in nitrogen activation of the fermentable-growth-medium-induced signalling pathway.

J Org Chem, 1998 Oct 16, 63(21), 7449 - 7455
Structurally Novel Bioconversion Products of the Marine Natural Product Sarcophine Effectively Inhibit JB6 Cell Transformation; El Sayed KA et al.; Sarcophytol A (1) and B (2) (see Chart 1) are cembrane-type diterpenes known to inhibit tumor promotion . Indicative of this inhibitory response, we currently report sarcophytol A (1) mediates dose-dependent diminution of 12-O-tetradecanoylphorbol 13-acetate (TPA)-induced transformation of JB6 cells . Moreover, a structurally related furanocembrane diterpene, sarcophine (3), isolated in good yield from the Red Sea soft coral Sarcophyton glaucum, was also found to serve as an effective inhibitor of JB6 cell transformation . This compound was subjected to preparative-scale fermentation with Absidia glauca ATCC 22752, Rhizopus arrhizus ATCC 11145, and Rhizopus stolonifer ATCC 24795, resulting in the production of 10 new metabolites (5-14) along with the known compound 7beta,8alpha-dihydroxydeepoxysarcophine (4) . Structures were elucidated primarily on the basis of 2D-NMR spectroscopy, with X-ray crystallography being used to establish the relative stereochemistry of metabolite 5 . When evaluated for potential to inhibit TPA-induced JB6 cell transformation, several of the metabolites mediated inhibitory responses greater than sarcophytol A (1) or sarcophine (3), most notably 7alpha-hydroxy-Delta(8(19))-deepoxysarcophine (6), which was comparable to 13-cis-retinoic acid . These studies provide a basis for further development of novel furanocembranoids as anticancer agents.

J Org Chem, 1998 Aug 21, 63(17), 5831 - 5837
Total Synthesis of Terprenin, a Novel Immunosuppressive p-Terphenyl Derivative; Yonezawa S et al.; We achieved a total synthesis of terprenin, a novel potent immunoglobulin E antibody suppressant which was obtained from the fermentation broth of Aspergillus candidus RF-5672 and has a highly oxygenated p-terphenyl skeleton with a prenyloxy side chain . The key steps relied on the Suzuki reaction to construct the terphenyl skeleton and on regioselective halogenations to selectively combine the aromatic rings . The highly efficient and practical production of this important natural product offers promise for the development of a new type of antiallergic drug.

J Org Chem, 1997 Apr 4, 62(7), 2148 - 2151
Phomacins: Three Novel Antitumor Cytochalasan Constituents Produced by a Phoma sp .
Alvi KA, Nair B, Pu H, Ursino R, Gallo C, Mocek U.
Three novel cytochalasans, phomacins A, B and C, were isolated from a fermentation broth of the fungus Phoma sp . and purified by HSCCC (high speed countercurrent chromatography) followed by HPLC . The structures were determined by 1D and 2D NMR techniques . All three compounds have shown potent inhibitory activity against the HT29 colonic adenocarcinoma cell line.

Zhong Yao Cai, 2001 Jul, 24(7), 469 - 70
{Assay of trace elements and heavy metals in different growth stages of Ganoderma lucidum}; Xing Z et al.; The trace elements and heavy metals in the different growth stages of Ganoderma lucidum were analyzed by ICP-MS, AFS and AAS . The fermented mycelia, fruiting bodies and spore contained all kinds of detected trace elements and heavy metals, the contents of which were higher in spore . The content of Se was same in different growth stages . Ganoderma lucidum had the ability of bio-enrichment of Ge.

Biotechnol Bioeng, 2001 Nov 20, 75(4), 424 - 38
Dynamical model development and parameter identification for an anaerobic wastewater treatment process; Bernard O et al.; This paper deals with the development and the parameter identification of an anaerobic digestion process model . A two-step (acidogenesis-methanization) mass-balance model has been considered . The model incorporates electrochemical equilibria in order to include the alkalinity, which has to play a central role in the related monitoring and control strategy of a treatment plant . The identification is based on a set of dynamical experiments designed to cover a wide spectrum of operating conditions that are likely to take place in the practical operation of the plant . A step by step identification procedure to estimate the model parameters is presented . The results of 70 days of experiments in a 1-m(3) fermenter are then used to validate the model .

Biotechnol Bioeng, 2001 Nov 20, 75(4), 406 - 15
Improved rapid sampling for in vivo kinetics of intracellular metabolites in Saccharomyces cerevisiae; Lange HC et al.; An integrated approach is used to develop a rapid sampling strategy for the quantitative analysis of in vivo kinetic behavior based on measured concentrations of intracellular metabolites in Saccharomyces cerevisiae . Emphasis is laid on small sample sizes during sampling and analysis . Subsecond residence times are accomplished by minimizing the dead volume of the sterile sampling system and by maximizing flow rates through application of vacuum to the sampling tubes in addition to the overpressure in the fermenter . A specially designed sample tube adapter facilitates sampling intervals of 4 to 5 s for various test tube types . Statistical analysis of the results obtained from enzymatic and liquid chromatography mass spectrometry (LC-MSMS) analysis of the metabolite concentrations was used to optimize the sampling protocol . The most notable improvement is reached through the introduction of vacuum drying of the cell extract . The presented system is capable of reliably dealing with fermenter samples as small as 1-g with a variation of less than 3%, and is thus ideally suited for intracellular measurements on small, lab-scale fermenters .

J Org Chem, 1996 Sep 20, 61(19), 6591 - 6593
Arthrichitin . A New Cell Wall Active Metabolite from Arthrinium phaeospermum; Vijayakumar EK et al.; Arthrichitin (1), C(33)H(46)N(4)O(9), is a new cell wall active depsipeptide isolated from the fermentation broth of Arthrinium phaeospermum (HIL Y-903022) . Its structure was elucidated on the basis of spectroscopic and chemical degradation studies . Arthrichitin consists of serine, beta-keto tryptophan, glutamic acid, and 2,4-dimethyl-3-hydroxydodecanoic acid units.

Appl Biochem Biotechnol, 2001 Jul, 95(1), 59 - 67
Bioemulsifier production in batch culture using glucose as carbon source by Candida lipolytica; Sarubbo LA et al.; The yeast Candida lipolytica IA 1055 produced an inducible extracellular emulsification activity while utilizing glucose at different concentrations as carbon source during batch fermentation at 27 degrees C . In all glucose concentrations studied, maximum production of emulsification activity was detected in the stationary phase of growth, after pH reached minimal values . The bioemulsifier isolated was a complex biopolymer constituting proteins, carbohydrates, and lipids . The results obtained in this work show that the biosynthesis of a bioemulsifier is not simply a prerequisite for the degradation of extracellular hydrocarbon.

Appl Biochem Biotechnol, 2001 Jul, 95(1), 45 - 57
Continuous cultivation of dilute-acid hydrolysates to ethanol by immobilized Saccharomyces cerevisiae; Taherzadeh MJ et al.; The continuous cultivation of immobilized Saccharomyces cerevisiae CBS 8066 on dilute-acid hydrolysates of forest residuals was investigated . The yeast cells were immobilized in 2-4% Ca-alginate beads . The 2% beads were not stable . However, the 3 and 4% beads were stable for at least 3 wk when an extra resource of calcium ions was available in the medium . The continuous cultivation of a dilute-acid hydrolysate by the immobilized cells at dilution rates of 0.3, 0.5, and 0.6 h(-1) resulted in 86, 83, and 79% sugar consumption, respectively, and an ethanol yield between 0.45 and 0.48 g/g . The hydrolysate was fermentable at a dilution rate of 0.1 h(-1) in a free-cell system but washed out at a dilution rate of 0.2 h(-1) . The continuous cultivation of a more inhibiting hydrolysate was not successful by either free- or immobilized-cell systems even at a low dilution rate of 0.07 h(-1) . However, when the hydrolysate was overlimed, it was fermentable by the immobilized cells at a dilution rate of 0.2 h(-1).

Food Addit Contam, 2001 Nov, 18(11), 1004 - 10
Effect of fermentation on naturally occurring deoxynivalenol (DON) in Argentinean bread processing technology; Samar MM et al.; The stability of naturally occurring DON was evaluated during the fermentation stage of the bread-making process on a pilot scale . Two different products, French bread and Vienna bread, were prepared with naturally contaminated wheat flour (150 mg kg(-1)) under controlled experimental conditions . Dough was fermented at 30, 40 and 50 degrees C according to standard procedures employed in Argentinean low-technology bakeries . When the dough was fermented at 50 degrees C, the maximum reduction was 56% for the Vienna bread, with French bread being reduced by 41% . DON reduction during bread-making occurs not only in the baker due to thermal decomposition, but also during the fermentation step . The Argentinean traditional bread-making process might reduce DON levels during the fermentation stages if the dough is leavened at temperatures > 30 degrees C.

J Ind Microbiol Biotechnol, 2001 Aug, 27(2), 87 - 93
Application of multistage continuous fermentation for production of fuel alcohol by very-high-gravity fermentation technology; Bayrock DP et al.; A fermentation system to test the merging of very-high-gravity (VHG) and multistage continuous culture fermentation (MCCF) technologies was constructed and evaluated for fuel ethanol production . Simulated mashes ranging from 15% to 32% w/v glucose were fermented by Saccharomyces cerevisiae and the dilution rates were adjusted for each glucose concentration to provide an effluent containing less than 0.3% w/v glucose (greater than 99% consumption of glucose) . The MCCF can be operated with glucose concentrations up to 32% w/v, which indicates that the system can successfully operate under VHG conditions . With 32% w/v glucose in the medium reservoir, a maximum of 16.73% v/v ethanol was produced in the MCCF . The introduction of VHG fermentation into continuous culture technology allows an improvement in ethanol productivity while producing ethanol continuously . In comparing the viability of yeast by methylene blue and plate count procedures, the results in this work indicate that the methylene blue procedure may overestimate the proportion of dead cells in the population . Ethanol productivity (Yps) increased from the first to the last fermentor in the sequence at all glucose concentrations used . This indicated that ethanol is more effectively produced in later fermentors in the MCCF, and that the notion of a constant Yps is not a valid assumption for use in mathematical modeling of MCCFs.

Eur J Clin Nutr, 2001 Nov, 55(11), 1000 - 7
Prospective study on milk products, calcium and cancers of the colon and rectum; Jarvinen R et al.; OBJECTIVE: To study the relationship between consumption of milk and milk products, calcium, lactose and vitamin D and occurrence of colorectal cancers . DESIGN: Prospective cohort study . SUBJECTS: A total of 9959 men and women aged 15 y or older without history of cancer at baseline . During a 24 y follow-up, 72 new cancers of the large bowel (38 in the colon and 34 in the rectum) were detected . RESULTS: Consumption of milk and total milk products was suggested to be inversely related to colon cancer incidence, whereas no similar association was seen for rectal cancer . The relative risk between the highest and lowest quartiles of intake adjusted for potential confounding factors was 0.46 (95% confidence interval 0.14-1.46, P for trend 0.09) for milk and 0.37 (95% CI=0.12-1.39, P for trend 0.06) for total milk products . Lactose intake showed a similar inverse relationship with colon cancer: the relative risk was 0.31 (95% CI=0.08-1.15, P for trend 0.03) . Intake of vitamin D or total dietary calcium was not significantly related to colorectal cancer risk, whereas calcium provided by fermented milk products was associated with increased colorectal cancer incidence; in the highest quartile the multivariate adjusted relative risk for colorectal cancer was 2.07 (95% CI=1.00-4.28) . CONCLUSIONS: Our results indicate that individuals showing high consumption of milk have a potentially reduced risk of colon cancer; however, the association does not appear to be due to intake of calcium, vitamin D, or to specific effects of fermented milk . SPONSORSHIP: This study was supported by a grant from the Swedish Cancer Foundation.

Ann Sci, 1994 Nov, 51(6), 593 - 613
Microbes at work: micro-organisms, the D.S.I.R . and industry in Britain, 1900-1936; Vernon K; The study of micro-organisms in Britain in the early twentieth century was dominated by medical concerns, with little support for non-medical research . This paper examines the way in which microbes came to have a place in industrial contexts in the 1920s and early 1930s . Their industrial capacity was only properly recognized during World War I, with the development of fermentation processes to make required organic chemicals . Post-war research sponsored by chemical and food industries and the D.S.I.R established the industrial significance of microbes . The primary focus here is the D.S.I.R . work which aimed to pull microbes away from medical concerns and promote the role of microbes in British industry.

Rev Soc Venez Hist Med, 1992 Jun, 41(61), 101 - 19
Not Available
Cordero-Moreno R.
This work is a very summarized Louis Pasteur's biography . As a scientist he discovered the dimorphism of the tartric acid cristals, the fermentation of several compounds (biere, wine, vinager, butter) and how to avoid them thru the pasteurization, he also discovered the bacterial cause of many diseases of man and animals, changing the ways of human life . Thru sterilization, since him, the fatal outcome of many patients is avoided and surgery was made safe . He established bacteriology and immunology as branches of medicine and biology.

NTM, 1996, 4(1), 31 - 51
Not Available
Hoxtermann E.
The cultural history of alcoholic fermentation goes back to very early periods of human being . But only in the 19th century the nature of the biological production of alcohol was discovered . In that time chemistry and botany had a different, complementary view to alcoholic fermentation . While the positions of chemists are well-known and much discussed in the historiography of science the contribution of botanists to fermentation research is almost entirely forgotten nowadays . The work of the mycologist Oscar Brefeld, who studied yeast fermentation from 1873 to 1876, illustrates the special botanical view to the ontogenetical side of alcoholic fermentation, to morphlogical and physiological differences between growing and dying, fermenting and fermented yeast cells, and to the energetic and ecological role of fermentation as well as its universality in vegetable kingdom.

Med Nowozytna, 1997, 4(1-2), 63 - 83
{Historian and physician as researchers of the history of medical sciences}; Jeszke J; It can be observed that recently the historiography of medical sciences has anew searched for its own identity and its place among other medical and historical sciences . On the one hand, the researchers in this field are not physicians exclusively any longer but more and more frequently the representatives of other medical professions and professional historians, as well . On the other hand, the major direction of interest to the history of medical sciences, i.e . cultivating the traditions of medical professions and molding the attitudes of environments related with them is not sufficient in the long run . The variety of extra source knowledge, shared in the community of researches, diverse research approaches, hierarchy of problems worth studying and, finally scientific traditions individual research groups derive from have produced a significant ferment in the medical environments . At last disputes have been held, although quite often unofficially during various scientific meetings, on professional qualification of a historian of medical sciences and sometimes on the scope of his or her discipline . The author analyzes in detail the divergence in the features of individual study approaches for both groups and their consequences . The author's standpoint is that it is necessary to be aware of the diverse study approaches and hierarchy of problem eligible for studying to break the distinction and create interdisciplinary units . This will allow an interparadigmatic dialog, a professional division of work and search for the area of common interest, while retaining methodological autonomic features.

Rev Hist Pharm (Paris), 1997, 45(314), 147 - 52
{A brief philatelic evocation of Louis Pasteur and of his disciples}; Jouzier E; Philately is an important source of knowledge on numerous items . Evocation of Louis Pasteur's as well as his disciples life and works throughout stamp collection is a perfect example of this . Born in Dole in 1822, he spent his youth in Arbois . It is at the Ecole normale superieure that he performed his work on cristals which led him to establish molecular dissymetry principles . Later, he studied of the fermentation process, he searched the reason of wines' disease and the means to prevent it (i.e . pasteurisation), he solved the problem of the silkworm disease and discovered agents of numerous infectious diseases . He demonstrated scientifically the vaccination principle . In 1885 he tried with success the first human antirabic vaccination . Three years later, the Pasteur Institute was inaugurated . After his death, his works survived in numerous institutes all over the world . Many pasteurians received the Nobel Prize.

Cuad Complut Hist Med Cienc, 1993, 2, 275 - 94
{Belgian law on the Régime de l'alcool of 1919: from the individual measures to social well-being}; Campos R; There was a tightening up of the fight against alcoholism in various European countries and the United States during the first world war . The individual and private initiatives were relegated to second place in Belgium during the period 1914-1918, and the state took the reins in the fight against alcoholism on behalf of the general interests of the health interests and general well-being of the population . The promulgation of "La loi sur le Regime de l'alcool" and "La loi concernant les debits des Boissons Fermentes" on August 29 1919 was the final step in this change in opinion . There were three factors which coincided during the armed conflict and which played a definitive part in the preparation of these laws: 1) the legislation against alcohol which the Belgian authorities promulgated during the war in order to keep order and discipline in the army; 2) the problems of national reconstruction and 3) the influence that Emile Vandervelde, the leader of the Belgian Workers Party had on his entry into the government of the "Union Sacree".

Cuad Complut Hist Med Cienc, 1993, 1, 239 - 61
{The theory of contagion in French pathology prior to the work of Pasteur}; Garcia Guerra D; The main sources of information used by the author for this study dealing with ideas on contagion prior to the work of Pasteur were French treatises on general pathology . These range from that of Chomel (1817) to those of the 1860, by which time Pasteur was studying the micro-organism which cause fermentations . The main aim is to analize how the conceptual framework which permited the constitution of the microbian theory of infectious disease became established . The authors studies provide a series of responses to the problem of contagious disease which, although different to the old theory or animated contagion, come very close in some aspects to those responses that arose later towards the end of the century.

Ber Wissenschaftsgesch, 1998 Dec, 21(4), 231 - 6
Not Available
Weyer-von Schoultz M.
By studying the etiology and the causalities of the cholera breaking out in the German cities since the 1830s the young scientific discipline "Hygiene" tried to influence urban administrations to prevent the contamination of the soil with human excrements . Most of the Hygienists followed the theory developed by Max von Pettenkofer, the first German professor of Hygiene, that the soiling was the causing factor of most of the intestinal diseases . This theory based on the hypothesis of a prerequisite fermentation of a germ in the soil before being capable to produce disease in a susceptible individual . According to this - never irrefutably proved - theory the cities should be aware of the condition of soil (Bodenbeschaffenheit), whereas the pollution of the running water was not considered to be dangerous by reason of the supposed self-purification of running streams.

Res Microbiol, 2001 Sep, 152(7), 653 - 61
The arcABC gene cluster encoding the arginine deiminase pathway of Oenococcus oeni, and arginine induction of a CRP-like gene; Tonon T et al.; Oenococcus oeni, the main species which induces malolactic fermentation in wine, uses arginine via the arginine deiminase (ADI) pathway . Using degenerated primers, two specific probes, one for ornithine transcarbamoylase (OTC) and the other for carbamate kinase (CK), were synthesized . These made it possible to clone and sequence a cluster containing genes encoding ADI (arcA), OTC (arcB) and CK (arcC) . In addition, sequence analysis upstream of the arcA gene revealed the presence of an open reading frame (orf229) whose 3'-end was only 101 bp-distant from the start codon of the arcA gene and showed similarity with members of the FNR (regulation for fumarate and nitrate reduction) and CRP (cAMP receptor protein) family of transcriptional regulators . Moreover, a putative binding site for such regulators lies in the promoter region of the arcA gene . Induction of the arc cluster by arginine was studied first at the enzymatic level . The activities of the three enzymes strongly increased when cells were grown in the presence of the amino acid . In addition, the influence of arginine on gene transcription was monitored by RT-PCR (reverse transcriptase-polymerase chain reaction) . Expression of the three arc genes, and particularly that of arcA, was positively affected by arginine supplementation and thus confirmed the enzymatic results . Moreover, transcription of the putative CRP-like gene orf229 was also stimulated by arginine . These data suggest that the protein encoded by orf229 could be a CRP-like regulator involved in the metabolism of O . oeni.

Mol Cell Biol, 2001 Nov, 21(22), 7569 - 75
Hsp104 interacts with Hsp90 cochaperones in respiring yeast; Abbas-Terki T et al.; The highly abundant molecular chaperone Hsp90 functions with assistance from auxiliary factors, collectively referred to as Hsp90 cochaperones, and the Hsp70 system . Hsp104, a molecular chaperone required for stress tolerance and for maintenance of {psi(+)} prions in the budding yeast Saccharomyces cerevisiae, appears to collaborate only with the Hsp70 system . We now report that several cochaperones previously thought to be dedicated to Hsp90 are shared with Hsp104 . We show that the Hsp90 cochaperones Sti1, Cpr7, and Cns1, which utilize tetratricopeptide repeat (TPR) domains to interact with a common surface on Hsp90, form complexes with Hsp104 in vivo and that Sti1 and Cpr7 interact with Hsp104 directly in vitro . The interaction is Hsp90 independent, as further emphasized by the fact that two distinct TPR domains of Sti1 are required for binding Hsp90 and Hsp104 . In a striking parallel to the sequence requirements of Hsp90 for binding TPR proteins, binding of Sti1 to Hsp104 requires a related acidic sequence at the C-terminal tail of Hsp104 . While Hsp90 efficiently sequesters the cochaperones during fermentative growth, respiratory conditions induce the interaction of a fraction of Hsp90 cochaperones with Hsp104 . This suggests that cochaperone sharing may favor adaptation to altered metabolic conditions.

Curr Opin Biotechnol, 2001 Oct, 12(5), 493 - 8
Advances in genomics for microbial food fermentations and safety; de Vos WM; The exponentially growing collection of genomic sequence information, the high-throughput analysis of expression products, and the ability to order this information using advanced bioinformatics are expected to affect biotechnology and life sciences in a profound and unprecedented way . These developments offer many possibilities to improve the functionality of fermentations by food-grade microorganisms and to increase the microbial safety of foods . It will be necessary to combine functional studies with comparative genomics approaches to provide effective strategies for improving the functionality and safety of foods.

J Biotechnol, 2001 Dec 14, 92(1), 27 - 35
Multidrug resistance as a dominant molecular marker in transformation of wine yeast; Kozovska Z et al.; Pure wine yeast cultures are increasingly used in winemaking to perform controlled fermentations and produce wine of reproducible quality . For the genetic manipulation of natural wine yeast strains dominant selective markers are obviously useful . Here we demonstrate the successful use of the mutated PDR3 gene as a dominant molecular marker for the selection of transformants of prototrophic wine yeast Saccharomyces cerevisiae . The selected transformants displayed a multidrug resistance phenotype that was resistant to strobilurin derivatives and azoles used to control pathogenic fungi in agriculture and medicine, respectively . Random amplification of DNA sequences and electrophoretic karyotyping of the host and transformed strains after microvinification experiments resulted in the same gel electrophoresis patterns . The chemical and sensory analysis of experimental wines proved that the used transformants preserved all their useful winemaking properties indicating that the pdr3-9 allele does not deteriorate the technological properties of the transformed wine yeast strain.

Surgery, 2001 Oct, 130(4), 570 - 6; discussion 576-7
Thoracoscopic esophagomyotomy for achalasia: preoperative patterns of acid reflux and long-term follow-up; Maher JW et al.; BACKGROUND: The best technique for surgical esophagomyotomy to treat achalasia remains contentious . The controversies include the best approach (thoracoscopic or laparoscopic) and the need for an antireflux procedure . Postoperative pH studies have suggested pathologic gastroesophageal reflux (GER) in many cases; however, control studies of reflux patterns are scarce . This study presents pH studies before esophagomyotomy as well as long-term follow-up of patients undergoing esophagomyotomy . METHODS: Forty-nine patients underwent esophagomyotomy (45 thoracoscopically, 4 laparoscopically) for achalasia . Before treatment, 24-hour pH studies were conducted for 38 patients with achalasia . The patients were evaluated postoperatively for dysphagia and reflux . Results were classified as excellent, good, fair, or poor . RESULTS: The findings of the pretreatment pH studies were abnormal in 15 patients (39%) . Twelve patients (32%) had GER either with esophageal fermentation (6 patients {16%}) or without fermentation (6 patients {16%}) . Eight percent had esophageal fermentation alone . There was no correlation between GER and previous pneumatic dilatation . Twenty-three patients (60%) had normal pH scores; of these, 24% had esophageal fermentation, whereas 29% had neither reflux nor fermentation . Operative results were excellent in 70% of patients, good in 10%, and fair in 20% . All patients considered their conditions improved . Four patients required a subsequent operation because of dysphagia (n = 3) or reflux (n = 1), and their original procedures were classified as failures . Their current status is fair (n = 2), good (n = 1), and excellent (n = 1) . GER was documented before the original operation in 3 of the 4 patients in whom the procedure failed . Fifteen patients were eligible for 5-year follow-up . Their results are excellent or good (n = 11) (73%) and fair (n = 4) (27%) . CONCLUSIONS: A high percentage of patients with achalasia exhibit pathologic GER before surgical therapy and seem to be at higher risk for failed surgical treatment . Thoracoscopic esophagomyotomy resulted in improvement in 92% of patients, and long-term follow-up indicates that these results are durable.

J Biol Chem, 2001 Dec 21, 276(51), 47844 - 52 Epub 2001 Oct 15.
Saccharomyces cerevisiae multidrug resistance gene expression inversely correlates with the status of the F(0) component of the mitochondrial ATPase; Zhang X et al.; Loss of the mitochondrial genome (rho(0) cell) or elimination of the mitochondrial inner membrane protein Oxa1p causes a dramatic increase in expression of the ATP binding cassette transporter-encoding gene PDR5 in the yeast Saccharomyces cerevisiae . This increase in gene expression occurs via activation of the function of the Cys(6)-Zn(II)(2) cluster transcription factor Pdr3p, which in turn autoregulates expression of its structural gene . Surprisingly, the acquisition of PDR5-dependent multidrug resistance occurs at a very high frequency, consistent with the appearance of rho(-) cells in a fermentatively growing culture (approximately 2%) . The degree of activation of Pdr3p target genes was found to vary considerably and to be influenced by the presence of the homologous protein, Pdr1p . Mutagenesis and overexpression studies provided evidence that the control of Pdr3p expression was the major control point of this transcription factor by mitochondrial retrograde signaling . Because both rho(0) and oxa1 mutant cells have multiple defects including loss of normal respiratory chain function and oxidative phosphorylation, a series of mutant strains with more selective defects in mitochondrial function was employed to identify the molecular signal that triggers PDR5 transcriptional activation . Only mutations that influenced the functional status of the F(0) subunit of the mitochondrial ATPase were found to lead to activation of PDR5 expression.

Med Hypotheses, 2001 Oct, 57(4), 429 - 31
Dysfunctional mitochondria, not oxygen insufficiency, cause cancer cells to produce inordinate amounts of lactic acid: the impact of this on the treatment of cancer; John AP; It has been known for decades that cancer cells produce excessive amounts of lactic acid . The fact that most cancers have poor vascular systems has led cancer scientists to assume that such cells are deprived of a normal supply of oxygen . Researchers believe that without sufficient oxygen, cancer cells must revert to fermentation for their energy supply and this is what causes them to produce excessive lactic acid . I challenge this traditional assumption and suggest instead that cancer cells have dysfunctional mitochondria, which prevent their use of the citric acid or Krebs cycle . Consequently, pyruvic acid, the end product of glycolysis, which normally would enter the mitochondria for its total combustion into energy, is instead converted to lactic acid . Evidence exists to support this hypothesis which, when acknowledged, could dynamically impact both cancer research and the treatment of all forms of cancer .

Appl Microbiol Biotechnol, 2001 Sep, 56(5-6), 670 - 5
Effect of exogenous lysine on the expression of early cephamycin C biosynthetic genes and antibiotic production in Nocardia lactamdurans MA4213; Leitao AL et al.; In beta-lactam producing microorganisms, the first step in the biosynthesis of the beta-lactam ring is the condensation of three amino acid precursors: alpha-aminoadipate, L-cysteine and D-valine . In Nocardia lactamdurans and other cephamycin-producing actinomycetes, alpha-aminoadipate is generated from L-lysine by two sequential enzymatic steps . The first step involves a lysine-6-aminotransferase activity (LAT), considered to be one of the rate-limiting steps for antibiotic biosynthesis . Here, we report the effect of exogenous lysine on antibiotic production by N . lactamdurans MA4213 . Lysine-supplemented cultures showed higher titers of cephamycin C, an effect that was more significant at early fermentation times . The increase in cephamycin C production was not quantitatively correlated with specific LAT activity in lysine-supplemented cultures . Observation of a positive effect of lysine on cephamycin C production by N . lactamdurans was dependent on carbon source availability in the culture media . Supplementation of the culture media with exogenous lysine did not affect the mRNA levels of the early biosynthetic genes controlled by the bidirectional promoter . These results indicate that L-lysine is required not only for antibiotic biosynthesis, but particularly as carbon or nitrogen source.

Appl Microbiol Biotechnol, 2001 Sep, 56(5-6), 567 - 76
The use of micro-organisms for L-ascorbic acid production: current status and future perspectives; Hancock RD et al.; L-Ascorbic acid (L-AA) has been industrially produced for around 60 years in a primarily chemical process utilising D-glucose (D-glc) as starting material . Current world production is estimated at approximately 80,000 tonnes per annum with a worldwide market in excess of U.S . $600 million . We present a brief overview of research geared to exploiting micro-organisms for the industrial production of vitamin C, with emphasis on recent approaches using genetically engineered bacterial strains . We also discuss the potential for direct production of L-AA exploiting novel biochemical pathways with particular reference to yeast fermentations . The potential advantages of these novel approaches over current chemical and biotechnological processes are outlined.

Bioresour Technol, 2001 Dec, 80(3), 227 - 31
Effect of iron concentration on hydrogen fermentation; Lee YJ et al.; The effect of the iron concentration in the external environment on hydrogen production was studied using sucrose solution and the mixed microorganisms from a soybean-meal silo . The iron concentration ranged from 0 to 4,000 mg FeCl2 l(-1) . The temperature was maintained at 37 degrees C . The maximum specific hydrogen production rate was found to be 24.0 ml g(-1) VSS h(-1) at 4,000 mg FeCl2 l(-1) . The specific production rate of butyrate increased with increasing iron concentration from 0 to 20 mg FeCl2 l(-1) and decreased with increasing iron concentration from 20 to 4,000 mg FeCl2 l(-1) . The maximum specific production rates of ethanol (682 mg g(-1) VSS h(-1)) and butanol (47.0 mg g(-1) VSS h(-1)) were obtained at iron concentrations of 5 and 3 mg FeCl2 l(-1), respectively . The maximum hydrogen production yield of 131.9 ml g(-1) sucrose was obtained at the iron concentration of 800 mg FeCl2 l(-1) . The maximum yields of acetate (389.3 mg g(-1) sucrose), propionate (37.8 mg g(-1) sucrose), and butyrate (196.5 mg g(-1) sucros) were obtained at iron concentrations of 3, 200 and 200 mg FeCl2 l(-1), respectively . The sucrose degradation efficiencies were close to 1.0 when iron concentrations were between 200 and 800 mg FeCl2 l(-1) . The maximum biomass production yield was 0.283 g VSS g(-1) sucrose at an iron concentration of 3,000 mg FeCl2 l(-1).

J AOAC Int, 2001 Sep-Oct, 84(5), 1509 - 21
Detection of added beet or cane sugar in maple syrup by the site-specific deuterium nuclear magnetic resonance (SNIF-NMR) method: collaborative study; Martin YL; Results of a collaborative study are reported for the detection of added beet or cane sugar in maple syrup by the site-specific natural isotope fractionation-nuclear magnetic resonance (SNIF-NMR) method . The method is based on the fact that the deuterium content at specific positions of the sugar molecules is different in maple syrup from that in beet or cane sugar . The syrup is diluted with pure water and fermented; the alcohol is distilled with a quantitative yield and analyzed with a high-field NMR spectrometer fitted with a deuterium probe and fluorine lock . The proportion of ethanol molecules monodeuterated at the methyl site is recorded . This parameter (D/H)I is decreased when beet sugar is added and increased when cane sugar is added to the maple syrup . The precision of the method for measuring (D/H)I was found to be in good agreement with the values already published for the application of this method to fruit juice concentrates (AOAC Official Method 995.17) . An excellent correlation was found between the percentage of added beet sugar and the (D/H)I isotopic ratio measured in this collaborative study . Consequently, all samples in which exogenous sugars were added were found to have a (D/H)I isotopic ratio significantly different from the normal value for an authentic maple syrup . By extension of what is known about plants having the C4 cycle, the method can be applied to corn sweeteners as well as to cane sugar . One limitation of the method is its reduced sensitivity when applied to specific blends of beet and cane sugars or corn sweeteners . In such case, the C13 ratio measurement (see AOAC Official Method 984.23, Corn Syrup and Cane Sugar in Maple Syrup) may be used in conjunction.

J Agric Food Chem, 2001 Oct, 49(10), 5070 - 4
Protein digestibility-corrected amino acid scores for bean and bean-rice infant weaning food products; Kannan S et al.; Vegetable proteins are an integral part of infant weaning diets in Latin America . Protein quality in plant-based products, however, is constrained by amino acid composition and intrinsically present antinutritional factors . The goal of this study was to improve bean protein quality by utilizing fermentation and germination processing . The objectives were to determine if protein quality, as measured by Food and Agricultural Organization (FAO) approved True Protein Digestibility (TPD) and Protein Digestibility-Corrected Amino Acid Scores (PDCAAS), of formulated bean-based weaning products could be improved upon fermentation and germination and if protein quality could be further improved when processed beans were combined with cooked rice . Results showed that the highest TPD and PDCAAS values were obtained for cooked germinated beans combined with rice . The TPD values for products ranged from 80 to 91%, and the PDCAAS values were 0.38-0.51 . There was no significant increase (P < 0.05) of either TPD or PDCAAS values upon fermentation . Germination increased TPD of cooked bean products; this increase was not, however, accompanied by an increase in PDCAAS . When combined with rice, the PDCAAS values for all bean products improved significantly, thus supporting the concept of cereal-legume complementation . In conclusion, this study showed the range of PDCAAS in processed black bean and bean-rice infant weaning food products . The potential for incorporation of these products into the diets of weaning age Latin American children would, however, be confirmed only after validation with growth or metabolic balance studies in human infants.

J Agric Food Chem, 2001 Oct, 49(10), 5063 - 9
Iron and zinc bioavailability in rats fed intrinsically labeled bean and bean-rice infant weaning food products; Kannan S et al.; Beans are the core of the Latin American diet and contain iron and zinc . However, the bioavailability of these trace minerals from beans is low . The objective of this study was to determine if the bioavailability of iron and zinc could be improved with the use of fermentation and germination processing technologies . Black beans native to Costa Rica were grown hydroponically with either radioactive iron or zinc . The influence of fermentation and germination on iron and zinc bioavailability from intrinsically labeled infant weaning food products based on black beans and beans-rice was determined in rats . Mineral bioavailability was determined using whole-body (59)Fe retention for iron, and whole-body (65)Zn retention and incorporation of radiolabel into bone for zinc . Percent absorption of (59)Fe from fermented products ranged between 48.0 and 58.0 . Percent absorption of (65)Zn ranged from 57.0 to 64.0 . Fermentation did not increase iron bioavailability in rats fed fermented beans without rice . Fermentation of cooked beans significantly increased zinc retention . Germination significantly enhanced iron retention from cooked beans from 46 to 55% and from cooked beans-cooked rice from 34 to 48% . Germination significantly improved zinc absorption and retention from cooked beans without added rice.

J Agric Food Chem, 2001 Oct, 49(10), 4833 - 5
Formation of furfurylthiol exhibiting a strong coffee aroma during oak barrel fermentation from furfural released by toasted staves; Blanchard L et al.; Furfurylthiol (FFT) is formed in white wines during alcoholic fermentation in the barrel from the furfural released by toasted staves . The quantity of furfural released into the must has a decisive effect on the quantity of FFT in the finished wine . Wines fermented in new barrels thus contain larger quantities of FFT than those fermented in used barrels . Fermentation conditions favorable to an excess production of H(2)S (hydrogen sulfide) by the yeast promote the formation of this volatile thiol . The presence of this volatile thiol in white wines is, therefore, closely related to the yeast's sulfur metabolism.

Crit Rev Biotechnol, 2001, 21(3), 155 - 75
Microbial metabolism as an evolutionary response: the cybernetic approach to modeling; Patnaik PR; The growth and metabolic capabilities of microorganisms depend on their interactions with the culture medium . Many media contain two or more key substrates, and an organism may have different preferences for the components . Microorganisms adjust their preferences according to the prevailing conditions so as to favor their own survival . Cybernetic modeling describes this evolutionary strategy by defining a goal that an organism tries to attain optimally at all times . The goal is often, but not always, maximization of growth, and it may require the cells to manipulate their metabolic processes in response to changing environmental conditions . The cybernetic approach overcomes some of the limitations of metabolic control analysis (MCA), but it does not substitute MCA . Here we review the development of the cybernetic modeling of microbial metabolism, how it may be combined with MCA, and what improvements are needed to make it a viable technique for industrial fermentation processes.

J Ind Microbiol Biotechnol, 2001 Jul, 27(1), 58 - 61
Effects of methanol on expression of an anticoagulant hirudin in recombinant Hansenula polymorpha; Kim MD et al.; A series of batch, fed-batch, and continuous cultures was carried out to analyze the effects of methanol on the fermentation characteristics of recombinant Hansenula polymorpha for the production of hirudin, an anticoagulant . Hirudin expression efficiencies were greatly influenced by the methanol concentrations in continuous and fed-batch culture modes . At a steady state of continuous culture, an optimum methanol concentration of 1.7 g l(-1) was determined at a dilution rate of 0.18 h(-1) with 1.8 mg l(-1) h(-1) hirudin productivity.

J Ind Microbiol Biotechnol, 2001 Jul, 27(1), 52 - 7
Ethanol production from starch by immobilized Aspergillus awamori and Saccharomyces pastorianus using cellulose carriers; Fujii N et al.; A simultaneous saccharification and fermentation (SSF) process was investigated to produce ethanol using two kinds of cellulose carriers that were respectively suitable for immobilization of Aspergillus awamori and Saccharomyces pastorianus . The maximum ethanol concentration attained by the batch operation was 25.5 g l(-1) . Under suitable conditions, both cellulose carriers with immobilized cells could be reused efficiently for three cycles . The total amount of ethanol production was 66.0 g (per 1 l working volume) after the repeated operation . Ethanol productivity mainly depends on a saccharification process . There is a limit in durability in the repeated batch operation, and it is important to maintain high activity of the fungus in order to produce ethanol efficiently.

J Ind Microbiol Biotechnol, 2001 Jul, 27(1), 46 - 51
Influence of dimethylsulfoxide on tylosin production in Streptomyces fradiae; Butler AR et al.; The polyketide aglycone, tylactone (protylonolide), does not normally accumulate during tylosin production in Streptomyces fradiae, suggesting that the capacity of the organism to glycosylate tylactone exceeds the capacity for polyketide synthesis . Consistent with this model, tylosin yields were significantly increased (due to bioconversion of the added material) when exogenous tylactone was added to fermentations . However, tylosin yield improvements were also observed (albeit at lower levels) in solvent controls to which dimethylsulfoxide (DMSO) was added . At least in part, the latter effect resulted from stimulation of polyketide metabolism by DMSO . This was revealed when the solvent was added to fermentations containing the tylA mutant, S . fradiae GS14, which normally accumulates copious quantities of tylactone.

J Ind Microbiol Biotechnol, 2001 Jul, 27(1), 34 - 8
Maltotriose fermentation by Saccharomyces cerevisiae; Zastrow CR et al.; Maltotriose, the second most abundant sugar of brewer's wort, is not fermented but is respired by several industrial yeast strains . We have isolated a strain capable of growing on a medium containing maltotriose and the respiratory inhibitor, antimycin A . This strain produced equivalent amounts of ethanol from 20 g l(-1) glucose, maltose, or maltotriose . We performed a detailed analysis of the rates of active transport and intracellular hydrolysis of maltotriose by this strain, and by a strain that does not ferment this sugar . The kinetics of sugar hydrolysis by both strains was similar, and our results also indicated that yeast cells do not synthesize a maltotriose-specific alpha-glucosidase . However, when considering active sugar transport, a different pattern was observed . The maltotriose-fermenting strain showed the same rate of active maltose or maltotriose transport, while the strain that could not ferment maltotriose showed a lower rate of maltotriose transport when compared with the rates of active maltose transport . Thus, our results revealed that transport across the plasma membrane, and not intracellular hydrolysis, is the rate-limiting step for the fermentation of maltotriose by these Saccharomyces cerevisiae cells.

Infect Immun, 2001 Nov, 69(11), 7173 - 7
A 4.1-kilodalton polypeptide in the cultural supernatant of Mycoplasma fermentans is one of the substances responsible for induction of interleukin-6 production by human gingival fibroblasts; Hasebe A et al.; The cultural supernatant of Mycoplasma fermentans induced interleukin-6 production by human gingival fibroblasts . The active entities were divided into hydrophilic and hydrophobic substances . In this study, we purified a 4.1-kilodalton polypeptide from the hydrophilic substances . It reacted with polyclonal antibodies to M . fermentans and activated human macrophages.

Infect Immun, 2001 Nov, 69(11), 6823 - 30
Bordetella pertussis autoregulates pertussis toxin production through the metabolism of cysteine; Bogdan JA et al.; Pertussis toxin (Ptx) expression and secretion in Bordetella pertussis are regulated by a two-component signal transduction system encoded by the bvg regulatory locus . However, it is not known whether the metabolic pathways and growth state of the bacterium influence synthesis and secretion of Ptx and other virulence factors . We have observed a reduction in the concentration of Ptx per optical density unit midway in fermentation . Studies were conducted to identify possible factors causing this reduction and to develop culture conditions that optimize Ptx expression . Medium reconstitution experiments demonstrated that spent medium and a fraction of this medium containing components with a molecular weight of <3,000 inhibited the production of Ptx . A complete flux analysis of the intermediate metabolism of B . pertussis revealed that the sulfur-containing amino acids methionine and cysteine and the organic acid pyruvate accumulated in the media . In fermentation, a large amount of internal sulfate (SO4(2-)) was observed in early stage growth, followed by a rapid decrease as the cells entered into logarithmic growth . This loss was later followed by the accumulation of large quantities of SO4(2-) into the media in late-stage fermentation . Release of SO4(2-) into the media by the cells signaled the decoupling of cell growth and Ptx production . Under conditions that limited cysteine, a fivefold increase in Ptx production was observed . Addition of barium chloride (BaCl2) to the culture further increased Ptx yield . Our results suggest that B . pertussis is capable of autoregulating the activity of the bvg regulon through its metabolism of cysteine . Reduction of the amount of cysteine in the media results in prolonged vir expression due to the absence of the negative inhibitor SO4(2-) . Therefore, the combined presence and metabolism of cysteine may be an important mechanism in the pathogenesis of B . pertussis.

Yao Xue Xue Bao, 1997 Aug, 32(8), 629 - 32
{Stimulatory effect of sodium deoxycholate on alpha-ergocryptine productivity of Claviceps purpurea 94002 (EKPN94002)}; Zhu P et al.; The stimulation of sodium deoxycholate (SDC) on alpha-ergocryptine production of Claviceps purpurea strain 94002 (EKPN94002) was investigated . Preliminary results indicated that SDC, as a stimulator and at appropriate concentrations, could obviously increase the extracellular and the total production levels of the ergot alkaloid . Satisfied results were obtained when 6.0 mg.L-1 of SDC was present in the seed and fermentation media . The possible mechanism was discussed.

Int J Syst Evol Microbiol, 2001 Sep, 51(Pt 5), 1901 - 9
Thermotoga petrophila sp . nov . and Thermotoga naphthophila sp . nov., two hyperthermophilic bacteria from the Kubiki oil reservoir in Niigata, Japan; Takahata Y et al.; Two hyperthermophilic bacteria, strains RKU-1T and RKU-10T, which grew optimally at 80 degrees C, were isolated from the production fluid of the Kubiki oil reservoir in Niigata, Japan . They were strictly anaerobic, rod-shaped fermentative heterotrophs . Based on the presence of an outer sheath-like structure (toga) and 16S rDNA sequences, they were shown to belong to the genus Thermotoga . Cells of strain RKU-1T were 2-7 microm by 0.7-1.0 microm, with flagella . They grew at 47-88 degrees C on yeast extract, peptone, glucose, fructose, ribose, arabinose, sucrose, lactose, maltose, starch and cellulose as sole carbon sources . Cells of strain RKU-10T were 2-7 microm by 0.8-1.2 microm, with flagella . They grew at 48-86 degrees C on yeast extract, peptone, glucose, galactose, fructose, mannitol, ribose, arabinose, sucrose, lactose, maltose and starch as sole carbon sources . While strains RKU-1T and RKU-10T reduced elemental sulfur to hydrogen sulfide, their final cell yields and specific growth rates decreased in the presence of elemental sulfur . Thiosulfate also inhibited growth of strain RKU-1T but not strain RKU-10T . The G+C contents of the DNA from strains RKU-1T and RKU-10T were 46.8 and 46.1 mol% . Phenotypic characteristics and 165 rDNA sequences of the isolates were similar to those of Thermotoga maritima and Thermotoga neapolitana, both being hyperthermophilic bacteria isolated from hydrothermal fields . However, the isolates differed from these species in their minimum growth temperatures, utilization of some sugars, sensitivity to rifampicin and the effects of elemental sulfur and thiosulfate on growth . The low levels (less than 31%) of DNA reassociation between any two of these hyperthermophilic Thermotoga strains indicated that the isolates were novel species . Analysis of the gyrB gene sequences supported the view that the isolates were genotypically different from these reference species . The isolates were named Thermotoga petrophila sp . nov., with type strain RKU-1T (= DSM 13995T = JCM 10881T), and Thermotoga naphthophila sp . nov., with type strain RKU-10T (= DSM 13996T = JCM 10882T).

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