Int J Food Sci Nutr, 1998 Sep, 49(5), 333 - 8 Assessment of cyanogenic glucoside (cyanide) residues in Mbege: an opaque traditional Tanzanian beer; Shayo NB et al.; Levels of cyanide in two varieties of malted millet, spent grain (Machicha) and opaque beer (Mbege) were determined . Protein content and amino acid composition of the malt, Mbege and Machicha were determined . Mbege was made in the laboratory using an improved method . The cyanide content of millet, malt, spent grain and Mbege were 40.6, 513.4, 18.9 and 8.1 ppm, respectively for the Moshi local millet variety . For Sumbawanga-2 millet variety the cyanide content was found to be 41.2, 489.2, 17.8 and 6.8 ppm for the millet, malt, spent grain and Mbege, respectively . The cyanide content increased linearly as the number of days of germination of the millet grain increased and the highest values of cyanide were attained on the third day of germination . Cyanogenic glucosides in the millet were enzymetically hydrolysed to respective cyanohydrins and volatile hydrogen cyanide due to low pH level of the Mbege which was 4 . Malting of the millet increased the protein content by 5% . Lysine, the most limiting amino acid in millet, increased by 20% . It was concluded that the fermentation process of the millet malt into Mbege is efficient in reducing the levels of cyanogenic glucosides below levels considered toxic and therefore rendering the product safe. Nat Immun, 1998, 16(4), 157 - 64 No evidence of IFN-gamma increase in the serum of HIV-positive and healthy subjects after subcutaneous injection of a non-fermented viscum album L . extract; Stoss M et al.; Iscador, an aqueous extract of Viscum album L., has been used for more than 80 years as an anticancer drug . Due to its immunomodulatory potential, since the onset of the AIDS epidemic it has also been applied in the treatment of HIV-positive and AIDS patients in the form of the preparation V . album QuFrF (VaQuFrF; Labor Hiscia, Arlesheim, Switzerland) . In in vitro investigations, incubation of peripheral blood mononuclear cells with V . album L . extracts resulted in stimulation of lymphocyte activity with increased gene expression and release of various cytokines and also of interferon gamma (IFN-gamma) . In the latent phase, HIV positives exhibit only slightly elevated IFN-gamma concentrations in serum in comparison with HIV negatives, but in the acute phase of AIDS, there is an increase in levels of IFN-gamma . As the assay of cytokine levels in serum is a simple method of measuring immune system reactions, the aim of this trial was to determine whether increases in serum IFN-gamma levels in HIV positives and HIV negatives can be detected using this method after repeated injections of VaQuFrF . Five healthy subjects and 13 HIV-positive patients were investigated . IFN-gamma concentrations in serum were assayed using an ELISA test kit (ELISA test; ENDOGEN, Cambridge, Mass., USA) . No drug-related elevation of serum IFN-gamma was observed at any time point during the trial . It can thus be concluded that this method is not suitable for direct investigation of the immunomodulatory effects of VaQuFrF in vivo. Exp Physiol, 1999 May, 84(3), 541 - 8 Inhibition of mucosal glycylsarcosine uptake by acetate in rat distal small intestine; Scharrer E et al.; Acetate deriving from microbial fermentation may occur at considerable concentrations in the distal small intestine, where it appears to be absorbed by two different mechanisms: acetate-HCO3- exchange and non-ionic diffusion . Whether acetate affects absorption of other nutrients at this intestinal site is not known . Therefore the influence of acetate (30 mmol l-1) on oligopeptide absorption was studied using an in vitro mucosal uptake technique allowing measurement of substrate uptake across the brush border membrane (BBM) . Acetate significantly inhibited mucosal uptake of 14C-labelled glycylsarcosine (Gly-Sar) at pH 6 and pH 7 in the presence of sodium . No inhibition occurred in the absence of sodium . Both acetate and the absence of sodium decreased Vmax of mucosal Gly-Sar uptake without substantially affecting the apparent Km value . Since it is well established that Vmax of peptide transport across the intestinal BBM depends on the size of the transmembrane H+ gradient as a driving force the present findings are in accordance with the assumption that acetate inhibits peptide absorption by attenuating the H+ gradient across the BBM, which depends on the presence of sodium. Mol Microbiol, 1999 Jun, 32(5), 1002 - 12 A Saccharomyces cerevisiae G-protein coupled receptor, Gpr1, is specifically required for glucose activation of the cAMP pathway during the transition to growth on glucose; Kraakman L et al.; In the yeast Saccharomyces cerevisiae the accumulation of cAMP is controlled by an elaborate pathway . Only two triggers of the Ras adenylate cyclase pathway are known . Intracellular acidification induces a Ras-mediated long-lasting cAMP increase . Addition of glucose to cells grown on a non-fermentable carbon source or to stationary-phase cells triggers a transient burst in the intracellular cAMP level . This glucose-induced cAMP signal is dependent on the G alpha-protein Gpa2 . We show that the G-protein coupled receptor (GPCR) Gpr1 interacts with Gpa2 and is required for stimulation of cAMP synthesis by glucose . Gpr1 displays sequence homology to GPCRs of higher organisms . The absence of Gpr1 is rescued by the constitutively activated Gpa2Val-132 allele . In addition, we isolated a mutant allele of GPR1, named fil2, in a screen for mutants deficient in glucose-induced loss of heat resistance, which is consistent with its lack of glucose-induced cAMP activation . Apparently, Gpr1 together with Gpa2 constitute a glucose-sensing system for activation of the cAMP pathway . Deletion of Gpr1 and/or Gpa2 affected cAPK-controlled features (levels of trehalose, glycogen, heat resistance, expression of STRE-controlled genes and ribosomal protein genes) specifically during the transition to growth on glucose . Hence, an alternative glucose-sensing system must signal glucose availability for the Sch9-dependent pathway during growth on glucose . This appears to be the first example of a GPCR system activated by a nutrient in eukaryotic cells . Hence, a subfamily of GPCRs might be involved in nutrient sensing. Hum Reprod, 1999 Jun, 14(6), 1470 - 2 Adhesion preventive effect of hyaluronic acid after intraperitoneal surgery in mice; Sawada T et al.; Prevention of intraperitoneal adhesion after gynaecological surgery is essential for maintaining postoperative fertility . In this study, the adhesion prevention effect was examined of a hyaluronic acid (HA) solution obtained from the fermentation method and having a molecular weight of 1.9x10(6) with high viscosity . Laparotomy was conducted on female mice 7 weeks old, whose menstrual periods were synchronized by pregnant mare serum gonadotrophin (PMSG) to injure the uterine horn surface . Intraperitoneal adhesions were favourably formed in 91.7% of cases induced with iodine abrasion, compared with 50% induced by electrosurgery . Intraperitoneal administration of HA was evaluated for its effect on the prevention of adhesions made by iodine abrasion . Adhesion prevention effects of HA were observed at concentrations of 0.3, 0.5, 0.75 and 1.0%, among which the most pronounced effect was with the use of a 0.3% solution (92.3% of cases) . Compared with the control group adhesion score of 2.0 +/- 0 . 8, significant decreases in adhesion scores were observed at all concentrations . HA with a molecular weight of 1.9x10(6) was recognized to have a definitive prevention effect on postoperative adhesions in mice after laparotomy and is considered to be a prospective material for future clinical use. Biotechnol Prog, 1999 May, 15(3), 529 - 39 In situ monitoring of an escherichia coli fermentation using a diamond composition ATR probe and mid-infrared spectroscopy Doak DL, Phillips JA. A diamond composition ATR probe was used in situ to obtain IR spectra on replicate Escherichia coli fermentations involving a complex medium . The probe showed excellent stability over a 6-month operating period and was unaffected by either agitation or aeration . The formation of an unknown was observed from IR spectra obtained during the sterilization; subsequent experiments proved this to be a reaction product between yeast extract and the phosphates used as buffer salts . Partial-least-squares-based calibration/prediction models were developed for both glucose and acetate using in-process samples . The resulting models had prediction errors of +/-0.26 and +/-0.75 g/L for glucose and acetic acid, respectively, errors which were statistically equivalent to the estimated experimental errors in the reference measurements . Relative concentration profiles for the unknown formed during sterilization could be generated either by tracking peak height at an independent wavelength or by self-modeling curve resolution of the spectral region overlapping that of glucose . These profiles indicated that this compound was metabolized simultaneously with glucose; upon depletion of the glucose, when the microorganism switched to consumption of acetic acid, utilization continued but at a lower rate . The data presented provide an extensive characterization of the performance characteristics of this in situ analysis and clearly demonstrate its utility not just in the quantitative measurement of multiple known species but in the qualitative evaluation of unknown species. Int J Food Microbiol, 1999 Mar 1, 47(1-2), 153 - 7 Glucosamine content of tempe mould, Rhizopus oligosporus; Sparringa RA et al.; The glucosamine content of Rhizopus oligosporus NRRL 2710 mycelium grown in different media was determined . In Sabouraud dextrose broth the glucosamine content ranged from 51 g (kg dry biomass)(-1) for mycelial pellets less than 5 mm diameter to 107 g kg(-1) for pellets 16-35 mm diameter . Mycelium grown on Sabouraud dextrose agar contained 111 g glucosamine (kg dry biomass)(-1) while that grown on soymilk agar, used to simulate growth on soybeans in tempe, contained 82 g kg(-1) . The estimation of glucosamine was reproducible, with a mean coefficient of variation of 4% for mycelial pellets and 11% for mycelium from agar media . It is suggested that a conversion factor of 12 g dry biomass (g glucosamine)(-1) is applicable to determine fungal biomass in tempe fermentation. Int J Food Microbiol, 1999 Mar 1, 47(1-2), 133 - 40 Saccharomyces cerevisiae cell fatty acid composition and release during fermentation without aeration and in absence of exogenous lipids; Bardi L et al.; Medium-chain fatty-acids (MCFA) are among the main aroma compounds of fermented beverages . High concentrations of MCFA have been found in sluggish and stuck fermentations . It has been suggested that they arrest cell growth, as they may be toxic, but the causes of sluggish and stuck fermentations are still unclear . The aim of this work was to see whether the production of MCFA is related to fatty acid synthesis in the absence of exogenous lipids and aeration, and whether their increase can be regarded as a consequence, instead of the cause, of sluggish and stuck fermentations . Two possibilities were considered: (i) MCFA are produced to replace unsaturated fatty acids (UFA) for cell membrane fluidity when the lack of oxygen makes desaturation of saturated fatty acids (SFA) impossible; or (ii) MCFA are produced following the release of medium-chain acyl-CoA from the fatty acid synthetase complex (FAS) due to the accumulation of SFA, and their hydrolysis to recycle CoA-SH . In the first hypothesis, MCFA should be active in cell metabolism and be found in cell structures; in the second, MCFA should be a discard and prevalently found outside the cell . We carried out a Saccharomyces cerevisiae fermentation experiment in a synthetic, lipid-free medium without aeration . We measured the fatty acid composition of yeast cells and the amounts of MCFA and their ethyl esters in the medium throughout the fermentation . Cell growth and the oxygen content of the medium were also monitored . We found that MCFA are not immobilized in cell structures, but mainly released into the medium . Cell growth is arrested because fatty acid biosynthesis is prevented by the lack of oxygen . The higher MCFA concentrations found in sluggish and stuck fermentations can be thus regarded as an effect, and not the cause, of this arrest . Some suggestions for the prevention of these events are proposed. Microbiol Res, 1999 May, 154(1), 27 - 34 Co-operative effects of protein engineering and vector optimization on high yield expression of functional bivalent miniantibodies in Escherichia coli; Kujau MJ et al.; The volumetric yield of functional phosphocholine-binding miniantibodies could be increased in E . coli fermentations by the combination of the following approaches: Firstly, miniantibody mutants with amino acid exchanges in the VH chain leading to improved folding were expressed . Secondly, the expression vector was stabilized by an efficient suicide system to prevent plasmid loss . Thirdly, the cells were grown to high cell densities in a stirred tank reactor. Biotechnol Prog, 1999 May-Jun, 15(3), 493 - 9 Aqueous two-phase systems containing urea: influence on phase separation and stabilization of protein conformation by phase components; Ramsch C et al.; During recombinant Escherichia coli fermentation with high expression levels, inclusion bodies are often formed . Aqueous two-phase systems have been used in the presence of urea for the initial recovery steps . To investigate phase behavior of such systems we determined phase diagrams of poly(ethylene glycol) (PEG)/sodium sulfate/urea/water and PEG/dextran T-500 (DEX)/urea/phosphate buffer/water at different concentrations of urea and different molecular weight of PEG . PEG/Na2SO4 aqueous two-phase systems could be obtained including up to 30% w/w urea at 25 degrees C and PEG/dextran T-500 up to 35% w/w urea . The binodial was displaced toward higher concentrations with increasing urea concentrations . The partition coefficient of urea was near unity . An unstable mutant of T4-lysozyme with an amino acid replacement in the core (V149T) was used to analyze the effect of phase components on the conformation of the enzyme . We showed that partitioning of tryptophan was not dependent on the concentration of urea in the phase system. Am J Chin Med, 1999, 27(1), 53 - 62 Antiviral effect of gingyo-san, a traditional Chinese herbal medicine, on influenza A2 virus infection in mice; Kobayashi M et al.; Gingyo-san is a crude drug containing extracts from 7 medicinal plants and fermented soybeans in a specific ratio . It has been used clinically in China as a therapeutic agent for the common cold . In the present study, we examined the antiviral effect of this agent on influenza virus infection in mice . Gingyo-san and its components were administered orally to mice 1 day before, then 1 and 4 days after the inhalation of a mouse-adopted strain of influenza A2 (H2N2) virus . After infection with a 10 LD50 of the virus, 100% of mice treated with 10 mg/kg of the agent survived as compared with a 0% survival of control mice treated with saline . Also, the mean survival days were increased and consolidation scores were decreased in treated mice as compared with those of control mice . Two components contained in the agent, extracts from Glycyrrhizae radix and Arctii fructus, expressed antiviral activities in mice infected with influenza virus . However, in vitro growth of influenza virus in MDCK cells or viability of the virus was not affected by these extracts or Gingyo-san . From these results Gingyo-san was shown to be an antiviral agent in mice infected with a lethal amount of a mouse-adopted strain of influenza A2 virus. Eur J Nutr, 1999 Apr, 38(2), 76 - 83 The carbohydrate crystalean and colonic microflora modulate expression of glutathione S-transferase subunits in colon of rats; Treptow-van Lishaut S et al.; BACKGROUND: Glutathione S-transferases (GSTs)* are an important class of phase II, predominantly detoxifying, enzymes . The supergene family is composed of several isoenzymes, hetero- and homodimers, with tissue specific distribution and levels of expression . The hypothesis is that a higher expression of individual proteins within a specific tissue may be associated with a decreased burden of exposure to reactive carcinogens and ultimately with a decreased cancer risk in this tissue . AIMS OF THE STUDY: Since nutrition is expected to contribute to the gene expression, it was the aim of this study to investigate the impact of dietary factors, especially resistant starch, and of the gut microflora, which may be influenced by diet, on the GSTs in colon cells of rats . METHODS: For this, a technique using high pressure liquid chromatography was established with which for the first time GST isoenzymes were analysed in colon cells and compared to the levels of the corresponding proteins in the liver of the same rat . RESULTS: It was found that colon cells contain mainly GST pi and low amounts of mu but not GST alpha . In contrast, the predominant form of GSTs in the liver was alpha, then mu and hardly and pi Altogether, liver cells had approximately tenfold more total GSTs than colon cells . The feeding of "Crystalean", a retrograded, high amylose starch which alters the fermentation profile and the composition of the microflora, led to higher levels of GST pi in the colon . Furthermore, the comparison of GSTs in colon cells of germ-free rats revealed they were much lower than those observed in rats with conventional microflora . CONCLUSIONS: These findings clearly demonstrate that the gut bacteria, or their metabolic products, enhance GST expression . The studies support the hypothesis that nutrition--by affecting the gut flora--may induce this potentially protective and important class of phase II enzymes in important tumor target cells. Brain Res, 1999 May 22, 829(1-2), 28 - 38 The role of brain cytokines in mediating the behavioral and neuroendocrine effects of intracerebral mycoplasma fermentans; Yirmiya R et al.; Intracerebral administration of Mycoplasma fermentans (MF), a small microorganism that has been found in the brain of some AIDS patients, induces behavioral and neuroendocrine alterations in rats . To examine the role of tumor necrosis factor-alpha (TNFalpha) and interleukin-1 (IL-1) in mediating these effects we measured MF-induced expression of TNFalpha and IL-1beta mRNA in various brain regions, and the effects of TNFalpha synthesis blockers and IL-1 receptor antagonist (IL-1ra) on MF-induced sickness behavior and adrenocortical activation . Intracerebroventricular (i.c.v.) administration of heat-inactivated MF induced the expression of both TNFalpha and IL-1beta mRNA in the cortex, dorsal hippocampus, amygdala, and hypothalamus . Pre-treatment of rats with either TNFalpha synthesis blockers, pentoxifylline or rolipram, or with IL-1ra did not attenuate MF-induced anorexia, body weight loss, and suppression of social behavior . However, simultaneous administration of both pentoxifylline and IL-1ra markedly attenuated MF-induced anorexia and body weight loss, but had no effect on the suppression of social behavior . Pre-treatment with pentoxifylline, but not with IL-1ra, significantly attenuated MF-induced corticosterone (CS) secretion . Together, these findings indicate that both TNFalpha and IL-1 participate, in a complementary manner, in mediating some of the behavioral effects of MF, whereas only TNFalpha, but not IL-1, is involved in mediating MF-induced adrenocortical activation . We suggest that cytokines within the brain are involved in mediating at least some of the neurobehavioral and neuroendocrine abnormalities that may be produced by MF in AIDS patients . Z Naturforsch {C}, 1999 Mar-Apr, 54(3-4), 186 - 90 Effects of trehalose and ethanol on yeast cytosolic pyrophosphatase; Lopes DH et al.; Trehalose has been described to protect several enzymes against destabilizing conditions . This sugar is naturally accumulated by yeast as a stress protectant . A common stress condition that yeast is normally submitted is the presence of ethanol, the by-product of fermentation process of several yeast . In this paper we show the effects of trehalose and ethanol, alone or together, on yeast pyrophosphatase, and the effects of these compounds on inhibition and unfolding of pyrophosphatase promoted by urea . We show that both trehalose and ethanol inhibit pyrophosphatase in a dose-dependent manner, and that the presence of ethanol does not modify the inhibition promoted by trehalose as well as the presence of trehalose does not modify the inhibition promoted by ethanol . The effects of trehalose on pyrophosphatase are completely reversible, but the inhibition caused by ethanol was only partially reversible . Incubation of pyrophosphatase with 10% (v/v) ethanol promoted an inhibition of 15%, and the control activity was completely recovered after removal of ethanol . On the other hand, when pyrophosphatase was incubated with 20% (v/v) ethanol an inhibition of 40% of the control activity was observed which persisted after removal of ethanol . Ethanol also potentiates the inhibition of pyrophosphatase promoted by urea, and contributes for an irreversible inactivation and unfolding of pyrophosphatase in the presence of urea . Trehalose, that protects this enzyme against the inhibition and unfolding promoted by the chaotropic compound urea, was inefficient to protect against the effects of ethanol . Trehalose was also efficient to prevent an irreversible inactivation induced by urea. Z Naturforsch {C}, 1999 Mar-Apr, 54(3-4), 175 - 80 Structure elucidation of a purple peptide found during the purification of a recombinant protein from Escherichia coli; Guzzetta AW et al.; A purple substance (4) partially co-purified with a recombinant human B-type natriuretic peptide (hBNP), following an E . coli fermentation . The structure of the compound was elucidated by NMR, electrospray and FAB mass spectrometry . The chromophore is a 1,4-naphthoquinone condensed with the N-terminal cysteine of a heptapeptide by its NH2- and SH-groups to form a dihydro-thiazine ring . The peptide sequence was determined as Cys-Lys-Val-Leu-Arg-Arg-His by mass spectrometric techniques . CID and data base matching identified it as the C-terminus of the 32-amino-acid recombinant peptide hBNP . This modification of an N-terminal Cys may be a more general phenomenon with implications for the production of heterologous proteins by microorganisms. J Antibiot (Tokyo), 1999 Mar, 52(3), 256 - 62 Novel naphthoquinones from a Streptomyces sp; Kulanthaivel P et al.; Cdc25A assay-guided fractionation of a fermentation broth derived from a Streptomyces sp . resulted in the isolation of four novel naphthoquinones 1-4 . Structures of these compounds were deduced by NMR and mass spectrometry . Two of them, 3 and 4, incorporate a modified cysteine residue which is observed for the first time in this class of natural products . Naphthoquinones 1-4 showed weak activity against cdc25A phosphatase. Appl Environ Microbiol, 1999 Jun, 65(6), 2781 - 3 Mechanism of alanine hyperproduction by arthrobacter oxydans HAP-1: metabolic shift to fermentation under nongrowth aerobic conditions Hashimoto Si, Katsumata R. Arthrobacter oxydans HAP-1 hyperproduces DL-alanine in a non-growth-associated manner . We found that decreased activities of pyruvate dehydrogenase and of the enzyme catalyzing NADH oxidation in the stationary phase are paralleled by a shift of pyruvate metabolism to alanine synthesis by L-alanine dehydrogenase . We propose that this enzyme functions as an electron sink even under aerobic conditions. J Nat Prod, 1999 May, 62(5), 730 - 3 New verticillin and glisoprenin analogues from gliocladium catenulatum, a mycoparasite of aspergillus flavus sclerotia Joshi BK, Gloer JB, Wicklow DT. Four new compounds (1-4) have been isolated from solid-substrate fermentation cultures of the sclerotial mycoparasite Gliocladium catenulatum . The structures of verticillins D (1), E (2), and F (3) were assigned on the basis of MS and NMR data and chemical derivatization . The structure of glisoprenin F (4) was assigned by analysis of MS and NMR results, and comparison of its spectral data to those of the known compound glisoprenin D (6). J Antibiot (Tokyo), 1999 Mar, 52(3), 224 - 30 A novel fungal metabolite NG-061 enhances and mimics neurotrophic effect of nerve growth factor (NGF) on neurite outgrowth in PC12 cells; Ito M et al.; During the course of our screening program for low molecular natural products with their ability to potentiate and/or mimic neurotrophic effect of NGF, a novel fungal metabolite, phenylacetic acid hydrazide derivative NG-061 was isolated from the fermentation broth of Penicillium minioluteum F-4627 . NG-061 enhanced and mimicked neurotrophic effect of NGF on neurite outgrowth in a rat pheochromocytoma cell line PC12. J Antibiot (Tokyo), 1999 Mar, 52(3), 215 - 23 Asterriquinones produced by Aspergillus candidus inhibit binding of the Grb-2 adapter to phosphorylated EGF receptor tyrosine kinase; Alvi KA et al.; Five new asterriquinone analogs (2-4, 6, 7), together with previously identified neoasterriquinone (1) and isoasterriquinone (5), were isolated from a fermentation broth of the fungus Aspergillus candidus and purified by HSCCC (high speed counter current chromatography) followed by HPLC . The structures were determined by 1D and 2D NMR and MS/MS techniques . All seven showed inhibitory activity against the binding of a recombinant protein containing the SH2 protein domain of Grb-2 to the tyrosine phosphorylated form of the EGF receptor tyrosine kinase . Some of these asterriquinones exhibited specific inhibition of Grb-2 binding compared to Grb-7 and PLC-gamma. Can J Microbiol, 1998 Dec, 44(12), 1171 - 6 Esterase activity and release of ethyl esters of medium-chain fatty acids by Saccharomyces cerevisiae during anaerobic growth; Bardi L et al.; During anaerobic fermentation, Saccharomyces cerevisiae releases large amounts of medium-chain fatty acids (MCFAs) and related ethyl esters which are very important for aromatic quality of fermented beverages . The physiological function of ester synthesis is not yet understood . As MCFAs are toxic, their conversion to esters has been proposed to be a detoxification mechanism . Esterases possess ester synthesizing ability . Throughout an anaerobic fermentation of a lipid-free synthetic medium carried out with a S . cerevisiae strain selected for wine making, we have monitored MCFA and ethyl ester production and, at the same time, measured growth and esterasic activity of intact cells . Because no correlation was found between the concentration of each fatty acid and its ethyl ester, there is no evidence that ester synthesis reduces the toxicity of MCFAs . Esterasic activity did not show any correlation with ester synthesis, but it was related to the release of MCFAs . A model is proposed in which ester synthesis is a consequence of the arrest of lipid biosynthesis resulting from a lack of oxygen . Under these conditions, an excess of acyl coenzyme A is produced, and acyl esters are formed as secondary products of reactions aimed at recovering free coenzyme A. Appl Environ Microbiol, 1999 Jun, 65(6), 2710 - 5 The quiescent-cell expression system for protein synthesis in Escherichia coli; Rowe DC et al.; The quiescent-cell expression system is a radical alternative to conventional fermentation for protein overproduction in Escherichia coli . It is dependent on the controlled overexpression of a small RNA called Rcd in hns mutant strains to generate nongrowing, quiescent cells which are not nutrient limited . Quiescent cells no longer produce biomass and have their metabolic resources channelled toward the expression of plasmid-based genes . The biosynthetic capacity of the system is demonstrated by its ability to express chloramphenicol acetyltransferase to more than 40% of total cell protein . Quiescent cells may provide an ideal environment for the expression of toxic as well as benign proteins. Appl Environ Microbiol, 1999 Jun, 65(6), 2333 - 40 Expression of the Escherichia coli pntA and pntB genes, encoding nicotinamide nucleotide transhydrogenase, in Saccharomyces cerevisiae and its effect on product formation during anaerobic glucose fermentation; Anderlund M et al.; We studied the physiological effect of the interconversion between the NAD(H) and NADP(H) coenzyme systems in recombinant Saccharomyces cerevisiae expressing the membrane-bound transhydrogenase from Escherichia coli . Our objective was to determine if the membrane-bound transhydrogenase could work in reoxidation of NADH to NAD+ in S . cerevisiae and thereby reduce glycerol formation during anaerobic fermentation . Membranes isolated from the recombinant strains exhibited reduction of 3-acetylpyridine-NAD+ by NADPH and by NADH in the presence of NADP+, which demonstrated that an active enzyme was present . Unlike the situation in E . coli, however, most of the transhydrogenase activity was not present in the yeast plasma membrane; rather, the enzyme appeared to remain localized in the membrane of the endoplasmic reticulum . During anaerobic glucose fermentation we observed an increase in the formation of 2-oxoglutarate, glycerol, and acetic acid in a strain expressing a high level of transhydrogenase, which indicated that increased NADPH consumption and NADH production occurred . The intracellular concentrations of NADH, NAD+, NADPH, and NADP+ were measured in cells expressing transhydrogenase . The reduction of the NADPH pool indicated that the transhydrogenase transferred reducing equivalents from NADPH to NAD+. Am J Trop Med Hyg, 1999 May, 60(5), 752 - 7 No serologic evidence of an association found between Gulf War service and Mycoplasma fermentans infection; Gray GC et al.; Occult occupational infection with Mycoplasma fermentans has been proposed as a cause for illness among Persian Gulf War veterans . Symptom data and sera from a 1994-1995 cross-sectional survey of Navy Seabees were used to select symptomatic and asymptomatic Gulf War veterans and nondeployed veterans to evaluate this hypothesis . Survey sera from 96 Seabees were matched to prewar (before September 1990) archived sera . Immunoblot serologic analyses were performed for M . fermentans in a controlled, blinded fashion . Both Gulf War veterans and nondeployed veterans had prewar and postwar serologic evidence of M . fermentans infection consistent with natural infection data . Among study subjects collectively, and stratified by Gulf War service, none of the immunoblot banding profiles (prewar or postwar) or their changes over time were associated with postwar symptoms . These serologic data do not support the hypothesis that Gulf War veterans have experienced Gulf War-related morbidity from M . fermentans infection. J Antibiot (Tokyo), 1999 Feb, 52(2), 117 - 26 Biosynthesis of the pyrroindomycins by Streptomyces rugosporus LL-42D005; characterization of nutrient requirements; Abbanat D et al.; Streptomyces rugosporus LL-42D005 was shown to produce the novel pyrroindomycin antibiotics . Production of pyrroindomycin (alpha) and chloro-pyrroindomycin (beta) was characterized in a semi-defined fermentation medium containing glucose, casein, phosphate, vitamins and minerals . Accumulation of pyrroindomycin beta increased with increasing concentrations of glucose, reaching maximum titers at approximately 5g/L glucose . Glucose concentrations greater than 7.5 g/L decreased pyrroindomycin beta yields . Inhibition of pyrroindomycin accumulation at higher glucose concentrations could be reversed by increasing the casein concentration . Ammonium chloride, arginine or glutamine could replace casein as the sole nitrogen source for growth and pyrroindomycin production . Glucose, fructose or mannitol were utilized as the sole carbon source, while sucrose, maltose, glycerol, corn oil and starch were poorly metabolized . Incubation of this isolate in a vitamin-deficient medium resulted in a delay in growth and pyrroindomycin production; this delay was eliminated by the addition of biotin . Addition of L-tryptophan to the medium resulted in the production of pyrroindomycin alpha as the major species. J Dairy Sci, 1999 May, 82(5), 957 - 66 Different techniques to study rumen fermentation characteristics of maturing grass and grass silage; Cone JW et al.; Grass samples were harvested during the 1993 growing season after a precut on April 27, 1993 and were stored frozen or left to ensile in 30-L buckets . Effects on chemical composition and fermentation kinetics of the maturation of the grass and of ensiling were investigated . Chemical composition and fermentation kinetics were determined using the gas production technique, in vitro techniques, and the nylon bag technique . Two silage samples were also investigated in vivo . Maturation caused a decrease in crude protein content and organic matter degradability and an increase in neutral detergent fiber, acid detergent fiber, and lignin contents . Degradation rates were highest for the youngest samples and decreased as grass and silage matured . This result could be observed from the first derivative of the cumulative gas production curves (i.e., the rate of gas production) and from the gas production parameters . The rate of degradation of the nonsoluble fraction of the young samples, determined using the gas production technique, was relatively higher in rumen fluid from a cow fed silage from grass cut at a young stage . More mature samples were degraded relatively faster in rumen fluid from a cow fed mature grass silage, suggesting a specific adaptation of the rumen microorganisms to the grass properties . There was a good relationship among the second phase of gas production (i.e., fermentation of the nonsoluble fraction), maturity of the grass and grass silage samples, degradability determined with the Tilley and Terry technique, and degradability determined after 46 h of incubation in rumen fluid . Results obtained with both of the different in vitro techniques and the nylon bag technique were confirmed by the in vivo experiments involving the two silage samples. Crit Rev Microbiol, 1999, 25(1), 19 - 38 Conventional and molecular methods for understanding probiotic bacteria functionality in gastrointestinal tracts; Ricke SC et al.; The recent successes of probiotic application to limit colonization of foodborne pathogens in the gastrointestinal tracts of food animals ensures continued commercialization and widespread use of such cultures . Given that the the fermentation response and ecological balance of the probiotic consortium appears to be essential for the effectiveness of the cultures, it is essential to develop a methodology to accurately identify and quantitate these organisms during commercial production as well as successful in vivo colonization after administration . However, if further optimization of the effectiveness of defined cultures is to be achieved, methods to assess expression of key metabolic processes occurring during establishment of the probiotic culture as well as its subsequent ability to limit foodborne pathogen colonization are needed . Conventional methods to study individual probiotic gastrointestinal organisms include selective plating to identify specific nutritional groups, but the requirement of strict anaerobiosis for the obligate anaerobic members of these cultures can confound sample handling and preparation . Immunological methods can circumvent some of these problems but are somewhat limited for assessing functionality . The main advantage of using molecular tools is that the genetic diversity of the microflora, as well as their gene activity data are obtainable, both at the community level and at the single species level . Methods are currently available that permit studying individual members of microbial consortia, fluxes in community diversity, spatial distribution of consortia members, and the expression of specific microbial genes within communities . These methods involve the utilization of both DNA- and RNA-targeted probes, gene amplification protocols, and mRNA analysis . The study of mechanisms and functionality can only enhance the potential of probiotic cultures for limiting foodborne pathogen colonization. Br J Nutr, 1999 Jan, 81(1), 59 - 64 Influence of sodium fumarate addition on rumen fermentation in vitro; Lopez S et al.; The influence of sodium fumarate on rumen fermentation was investigated in vitro using batch and semi-continuous cultures of mixed rumen micro-organisms taken from three sheep receiving a basal diet of hay, barley, molasses, fish meal and a mineral-vitamin supplement (500, 299.5, 100, 91 and 9.5 g/kg DM respectively) . Batch cultures consisted of 10 ml strained rumen fluid in 40 ml anaerobic buffer containing 200 mg of the same feed given to the sheep . Sodium fumarate was added to achieve a final concentration of 0, 5 or 10 mmol/l, as a result of the addition of 0, 250 or 500 mumol, equivalent to 0, 200 and 400 g/kg feed . CH4 production at 24 h (360 mumol in the control cultures) fell (P < 0.05) by 18 and 22 mumol respectively (SED 7.5) . Total gas production was increased by the addition of fumarate without significant accumulation of H2 . Substantial increases in acetate production (92 and 194 mumol; SED 26.7, P < 0.01) were accompanied by increases in propionate formation (212 and 396 mumol; SED 13.0, P < 0.001) . Longer-term effects of fumarate supplementation on ruminal fermentation and CH4 production were investigated using the rumen simulation technique (Rusitec) . Eight vessels were given 20 g basal diet/d, and half of them received a supplement of fumarate (disodium salt) over a period of 19 d . The response to the daily addition of 6.25 mmol sodium fumarate was a decrease in CH4 production of 1.2 mmol (SED 0.39, P < 0.05), equivalent to the consumption of 4.8 mmol H2, and an increase in propionate production of 4.9 mmol (from 10.4 to 15.3 (SED 1.05) mmol/d, P < 0.01) . The inhibition of CH4 production did not decline during the period of time that fumarate was added to the vessels . Thus, the decrease in CH4 corresponded well to the fraction of the fumarate that was converted to propionate . Fumarate had no significant (P > 0.05) effect on total bacterial numbers or on the number of methanogenic archaea, but numbers of cellulolytic bacteria were increased (8.8 v . 23.9 (SED 2.49) x 10(5) per ml, P < 0.01) . Fumarate also increased DM digestibility of the basal diet after 48 h incubation (0.476 v . 0.508 (SED 0.0123), P < 0.05) . Thus, it was concluded that sodium fumarate may be a useful dietary additive for ruminants, because it diverts some H2 from CH4 production and because it is able to stimulate proliferation of cellulolytic bacteria and digestion of fibre. Regul Toxicol Pharmacol, 1999 Apr, 29(2 Pt 2), S78 - 82 Comparative gastrointestinal tolerance of sucrose, lactitol, or D-tagatose in chocolate; Lee A et al.; D-tagatose is a potential new sugar substitute . Ingested D-tagatose is incompletely absorbed from the small intestine; unabsorbed D-tagatose reaches the colon where it is completely fermented . In a double-blind, controlled crossover study, the gastrointestinal effects were compared following acute consumption of 40 g plain chocolates containing 20 g of sucrose, lactitol, or D-tagatose by 50 healthy adults ages 18 to 24 years . Consumption of D-tagatose was not associated with a significant increase in the frequency of passing feces, or in the number of subjects passing watery feces . However, lactitol consumption was associated with an increase in both of these occurrences . Consumption of chocolate containing D-tagatose and lactitol resulted in significant increases in colic, flatulence, borborygmi, and bloating compared to consumption of the sucrose-containing chocolate, but the majority of symptoms were described as only "slightly more than usual." D-tagatose-containing chocolate did not provoke significantly more of these symptoms than lactitol-containing chocolate . A significant number of subjects reported nausea following consumption of D-tagatose chocolate compared to the sucrose chocolate control, and multiple symptoms occurred in some subjects . Overall, these results demonstrate that a 20-g dose of D-tagatose is tolerated well in comparison to lactitol . Regul Toxicol Pharmacol, 1999 Apr, 29(2 Pt 2), S66 - 70 Human tolerance to a single, high dose of D-tagatose; Buemann B et al.; The addition of 29 g D-tagatose added as a sweetener to a continental breakfast was tested for the appearance of gastrointestinal side effects in a double-blind randomized cross-over study with 29 g sucrose as a control treatment . The subjects reported the side effects during 72 h following the test meal on a questionnaire grading the symptoms on a five-level scale ranging from "none" to "very strong." Although "rumbling in the stomach," "distention," "nausea," "rumbling in the gut," "flatulence, " and "diarrhea" scored significantly higher with D-tagatose, the sugar otherwise was well tolerated in most of the subjects . Two cases of vomiting after D-tagatose were recorded but in one of the cases its relation to the D-tagatose intake was questionable . Only the "distention" score remained higher with D-tagatose for more than 24 h . Nausea, vomiting, and perceived distension may be due to an osmotic effect in the small intestine of unabsorbed D-tagatose . The increased flatus is caused by D-tagatose being fermented in the large intestine . Diarrhea may be explained by osmotic effects in the colon from nondegraded D-tagatose or nonabsorbed short-chain fatty acids produced by the increased fermentation . Regul Toxicol Pharmacol, 1999 Apr, 29(2 Pt 2), S29 - 35 Developmental toxicity study of D-tagatose in rats; Kruger CL et al.; D-tagatose is a low-calorie sweetener that tastes like sucrose . The developmental toxicity of D-tagatose was investigated in Crl:CD(SD)BR rats administered D-tagatose at three dose levels (4000, 12,000, and 20,000 mg/kg body wt/day) via gastric intubation on days 6-15 of gestation . No compound-related toxicity was seen among any of the maternal groups . No treatment-related clinical effects were seen in the maternal animals at the 4000 mg/kg/day dose level . At the mid- and high-dose levels, most maternal animals had unformed or watery stools; this effect was most prominent early in the treatment period (Gestation Days 6-8) . This effect was attributed to the osmotic effect of the large amount of D-tagatose given to the animals at these doses . Since D-tagatose is not digested or absorbed to a large extent, most of the sugar passes into the colon where it absorbs water and is fermented by colonic bacteria . Mean weight gain for the low- and mid-dose animals was comparable to the control; however, the high-dose group experienced a mean weight loss over the Gestation Day 6-9 interval . Over the entire treatment interval, however, mean weight gain for the high-dose animals was comparable to control . The decreased weight gain in the high-dose animals during the Gestation Day 6-9 interval was considered to be a direct result of laxation . In addition to the effect of laxation on body weight, reduced food consumption also contributed to the decreased weight gain . In the low-dose animals, no effect on food consumption was seen; however, both mid- and high-dose animals had food consumption values that were statistically significantly lower than the control . Food consumption was lowest during the Gestation Day 6-9 interval, the period when laxation was most prominent . Food consumption rebounded and was statistically significantly higher than the control for the mid- and high-dose animals during the posttreatment interval . Maternal liver weight for the low-dose animals was comparable to the control . However, a statistically significant increase in mean maternal liver weight was noted for the mid-and high-dose animals . Based on a lack of any corresponding histopathology, the increased liver weights were not considered toxicologically significant . There were no adverse effects on reproductive performance noted in any treatment group . No adverse treatment-related fetal effects on fetal weight, sex distribution, liver weight, or external, skeletal, or visceral malformations were noted at any dose level . J Anim Sci, 1999 May, 77(5), 1074 - 81 Effect of reconstituting field-dried and early-harvested sorghum grain on the ensiling characteristics of the grain and on growth performance and carcass merit of feedlot heifers; Huck GL et al.; The objective of this study was to determine whether reconstituting field-dried and early-harvested sorghum grain affected the fermentation characteristics and feed value of the ensiled grain when fed to feedlot heifers . In Trial 1, sorghum grain was harvested at 14% moisture, rolled, and reconstituted to 25, 30, or 35% moisture, then ensiled in laboratory-scale silos . Lactic acid concentration increased (d 5 to 90) and pH decreased more rapidly (d 3 to 90) as moisture level increased (P < .05) . Acetic acid concentration increased (P < .05) with moisture and day postfilling . Concentration of ethanol was highest (P < .05) in the 30 and 35% moisture grains from d 1 to 5, but by d 90 the ethanol concentration in the 25% moisture grain exceeded (P < .05) that of the two higher-moisture grains . Ammonia N concentration was lowest (P < .05) in the 25% moisture grain at all sampling times postfilling . In Trial 2, 288 heifers (BW = 286+/-83 kg) were used to compare the feeding value of rolled, ensiled sorghum grain harvested at 25% moisture to the same grain reconstituted to 30 or 35% moisture . A steam-flaked corn (SFC) diet served as the control . Final live weight; ADG; hot carcass weight; backfat depth; marbling score; kidney, pelvic, and heart fat; and liver abscess score were not affected by grain treatment (P > .10) . Dry matter intake was highest (P < .10) for heifers fed the 25 or 30% moisture sorghum grain diets and lowest for those fed the SFC diet; DMI for heifers fed the 35% moisture sorghum grain diet was intermediate . Feeding 35% moisture sorghum grain improved gain efficiency (P < .10) compared with feeding 25 or 30% moisture sorghum grain by 9.0 and 5.7%, respectively . We conclude that reconstituting sorghum grain beyond the typical moisture levels of 25 to 30% would enhance the fermentation characteristics of the ensiled grain and improve gain efficiency in feedlot heifers. Infect Immun, 1999 Jun, 67(6), 3061 - 5 Transcriptional activation of mRNA of intercellular adhesion molecule 1 and induction of its cell surface expression in normal human gingival fibroblasts by Mycoplasma salivarium and Mycoplasma fermentans; Dong L et al.; Lipoproteins in the cell membranes of both Mycoplasma salivarium and Mycoplasma fermentans were demonstrated to trigger the transcription of intercellular adhesion molecule-1 mRNA in normal fibroblasts isolated from human gingival tissue and to induce its cell surface expression by a mechanism distinct from that of Escherichia coli lipopolysaccharide . The lipid moiety of the lipoproteins was suggested to play a key role in the expression of the activity. Arzneimittelforschung, 1999 Apr, 49(4), 366 - 73 Study on local inflammatory reactions and other parameters during subcutaneous mistletoe application in HIV-positive patients and HIV-negative subjects over a period of 18 weeks; Stoss M et al.; Subcutaneous injections of fermented and unfermented aqueous extracts of Viscum album L . result in a local inflammatory reaction at the injection site . In this trial, the symptoms associated with this local reaction were investigated . Furthermore the occurrence of local reactions was tried to correlate with an increase in CD3/25- and CD8/38-positive lymphocyte counts, with eosinophilic granulocyte numbers, and with the formation of mistletoe lectin antibodies . Included in the trial were 30 HIV-antibody-positive patients and 17 healthy non-smokers, aged 24-51 years . The CD4 cell count in the HIV-negative subjects was > 800/microliter, compared with 200-600/microliter in the HIV-positive patients . All study participants had a Karnofsky score > or = 70 . The trial subjects were observed over a period of 18 weeks . With escalation of the dose of a fermented and unfermented extract of Viscum album L . (Iscador Qu Spezial and Viscum album QuFrF), there was an increase in local reactions . Erythema at the injection site was the most frequently reported symptom . Between the doses and the symptoms induration, swelling and pruritus were marked correlations . Effects of the application of mistletoe extracts on the immune system were demonstrated by an increase in CD3/25-positive lymphocyte counts and antibodies against mistletoe-lectins . There were no changes in eosinophilic granulocytes or CD8/38-positive lymphocyte populations . For evaluation of the therapeutic applications of mistletoe extracts in HIV-positive patients it is advisable to assess primarily activation of CD3-positive lymphocytes and the patient response on the basis of the local reaction . The local inflammatory reaction at the injection site is desirable and well tolerated if the reaction is smaller than 5 cm in diameter. Protein Expr Purif, 1999 Jun, 16(1), 109 - 19 Application of fed-batch fermentation to the preparation of isotopically labeled or selenomethionyl-labeled proteins; Studts JM et al.; An increasing demand for isotopically labeled samples for spectroscopic and crystallographic studies has led to a corresponding need for effective and efficient methods for producing these samples . The present work is based on the strategy of using an isotopically labeled compound as the growth-limiting nutrient during protein expression in Escherichia coli (DE3) strains . By using dissolved O2 and agitation rate data, the cell growth, feeding of the isotopic label, induction of protein expression, and the harvest of cells can be coordinated in a feedback controlled fermenter in a simple, easily defined manner . This approach is demonstrated for the nutrient-limited production of {U-15N}- and {U-13C, U-15N}-labeled toluene 4-monooxygenase effector protein in E . coli BL21(DE3) with isotopic abundance identical to that of the labeled precursors . For selective labeling, demonstrated with selenomethionine using methionine auxotroph E . coli B834(DE3), approximately 80-85% incorporation was obtained from methionine-dependent growth of the auxotroph followed by selenomethionine feeding and protein induction upon methionine depletion . This selective labeling is accomplished in a single culture, does not require washing or resuspension, minimizes costly incorporation of label into host cell mass prior to induction, and can be easily adapted to selective labeling with other amino acids . Moreover, cell mass yield from these experiments can be readily optimized to provide the desired level of protein for a given investigation from a single growth and purification . This combination provides an efficient, controllable option for isotopic labeling experiments . J Comp Physiol {B}, 1999 Apr, 169(3), 172 - 8 Mycophagy by small mammals in the coniferous forests of North America: nutritional value of sporocarps of Rhizopogon vinicolor, a common hypogeous fungus; Claridge AW et al.; We evaluated the nutritional value of sporocarps of Rhizopogon vinicolor, a common hypogeous fungus in the coniferous forests of North America, for two small mammal species: the Californian red-backed vole (Clethrionomys californicus) and the northern flying squirrel (Glaucomys sabrinus) . Although the nitrogen concentration of sporocarps was high, much of it was in non-protein form or associated with cell walls, suggesting that it may be of low nutritional value or protected from mammalian digestive enzymes . Sporocarps also had high concentrations of cell wall constituents, indicating low availability of digestible energy . When fed a diet of this fungus alone in a controlled feeding experiment both mammal species lost a small amount of body mass . Digestibilities of dry matter, nitrogen, cell wall constituents and energy from sporocarps by both species were lower than the digestibilities of other food types by other similarly sized small mammals . Red-backed voles digested the various components of sporocarps at least as well as the flying squirrels, even though they were almost six-fold smaller in body mass . This observation supports the notion that red-backed voles, like other microtine rodents, have morphological and physiological adaptations of the digestive system that are postulated to permit greater digestion of fibrous diets than predicted on the basis of body size . Despite this, our results re-affirm previous conclusions that hypogeous fungi are only of moderate nutritional value for most small, hindgut-fermenting mammals . Future studies should focus on the importance of mixed-species of fungi in the diet of small mammalian mycophagists. Adv Exp Med Biol, 1999, 459, 99 - 106 The impact of food processing on the nutritional quality of vitamins and minerals; Reddy MB et al.; Processing (including preparation) makes food healthier, safer, tastier and more shelf-stable . While the benefits are numerous, processing can also be detrimental, affecting the nutritional quality of foods . Blanching, for example, results in leaching losses of vitamins and minerals . Also, milling and extrusion can cause the physical removal of minerals during processing . The nutritional quality of minerals in food depends on their quantity as well as their bioavailability . The bioavailability of key minerals such as iron, zinc and calcium is known to be significantly affected by the fiber, phytic acid, and tannin content of foods . Concentrations of these constituents are altered by various processing methods including milling, fermentation, germination (sprouting), extrusion, and thermal processing . Vitamins, especially ascorbic acid, thiamin and folic acid, are highly sensitive to the same processing methods . The time and temperature of processing, product composition and storage are all factors that substantially impact the vitamin status of our foods. Bioelectromagnetics, 1999, Suppl 4, 46 - 51 Luminescent radio frequency radiation dosimetry; Kiel JL et al.; Thermoluminescent dosimetry has been the industry standard for ionizing radiation dosimetry because it is inexpensive, sensitive, and accurate . No such system exists for radio frequency radiation . This paper describes the state of the art of efforts toward developing such a system . Thermochemiluminescent (TCL) dosimetry, first reported in 1991, is a first step toward achieving this goal . However, it has had problems in the production of TCL materials and in conversion of the luminescent signal into specific absorption rate (SAR) . The former problem has been solved by the development of a genetically engineered Escherichia coli bacterium (JM 109/plC20RNR1.1), described herein, that produces the TCL material in a fermentation process . The latter problem stems from the difficulty in determining the structure of the currently best TCL material diazoluminomelanin . A theoretical approach for the solution of this problem has been achieved by combining equations for delayed fluorescence, temperature determination by TCL, and the free energy equation for equilibrium reactions . It has led to an explanation for the stable display of steady-state energy disposition, illustrated by TCL, in phantoms without the expected disruption by thermal conduction or convection, at frequencies ranging from 2.06 GHz to 35 GHz. Carcinogenesis, 1999 May, 20(5), 915 - 8 Polyethylene-glycol, a potent suppressor of azoxymethane-induced colonic aberrant crypt foci in rats; Corpet DE et al.; Bulking fibers and high water intake may decrease colon carcinogenesis in rats, and the risk of colorectal cancer in humans . We speculated that a non-fermented polymer, polyethylene-glycol (PEG) 8000, which increases stool moisture, might protect rats against colon carcinogenesis . Thirty female F344 rats were given a single injection of azoxymethane (20 mg/kg), and 7 days later randomized to AIN76 diets containing PEG (to provide 3 g/kg body wt/day), or no PEG (control) . Diets were given ad libitum for 105 days, then colon carcinogenesis was assessed by the aberrant crypt foci (ACF) test . ACF were scored blindly by a single observer . Dietary feeding of PEG almost suppressed ACF larger than one crypt, and strikingly decreased the total number of ACF per rat . PEG-fed rats had 100 times less large ACF than controls (0.8 and 83 respectively, P = 0.00001) . PEG-fed rats had 20 times less total ACF than control (six and 107 ACF/rat, respectively; P < 0.0001) . Two treated rats had no detectable ACF . PEG is 10 times more potent than other chemopreventive agents in this model . Since PEG is generally recognized as safe, its cancer-preventive features could be tested in humans. J Am Diet Assoc, 1999 May, 99(5), 558 - 63 Development of a soy food frequency questionnaire to estimate isoflavone consumption in US adults; Kirk P et al.; OBJECTIVE: To develop a dietary assessment instrument to measure soy food consumption and isoflavone intake and test it for reliability . DESIGN: A soy food frequency questionnaire, designed for use in this study, was administered twice to participants, separated by a 2-week interval . The questionnaire was tested for reproducibility of estimates of soy food consumption and isoflavone (genistein and daidzein) intake . SUBJECTS/SETTING: A convenience sample of 51 faculty, staff, and students was recruited from a naturopathic university . STATISTICAL ANALYSES PERFORMED: Intraclass correlation coefficients were used to assess reproducibility of estimates of soy food intake and genistein and daidzein intake . RESULTS: Correlation coefficients comparing mean soy food servings per month between the 2 administrations of the questionnaire ranged from 0.50 for soy yogurt to 0.89 for tempeh . Correlation coefficients for genistein and daidzein intake estimated by the 2 administrations of the questionnaire were the same: 0.89 . Mean intake (+/- standard deviation) of genistein and daidzein was 7 +/- 10 and 4 +/- 6 mg/day, respectively . Fifteen soy foods contributed 95% of the total genistein and daidzein intake: tofu, soy yogurt, tempeh, soy milk, low-fat tofu, soy flour, miso, soy protein isolate, low-fat soy milk, veggie soy burger, textured vegetable protein, miso soup, cooked soybeans, soy hot dogs, and natto (fermented soy beans) . APPLICATIONS: The soy food frequency questionnaire developed in this study provided highly reproducible estimates of soy food consumption and isoflavone intake . This instrument may be a useful tool in studies of the associations between isoflavone exposure and risk for chronic disease. J Anim Sci, 1999 Apr, 77(4), 979 - 87 Influence of sampling site on concentrations and carbohydrate-degrading enzyme activities of protozoa and bacteria in the rumen; Martin C et al.; Four ruminally cannulated cows were used to assess the distribution of the concentrations and carbohydrate-degrading enzyme activities of the liquid-associated protozoa (LAP) and solid-associated bacteria (SAB) in the rumen . The cows were fed diets (7 kg of DM/d) of 100% hay (Diet F) or 60% barley plus 40% hay (Diet C) in a 2 x 2 crossover experimental design . Samples of ruminal digesta were collected successively from the dorsal (DS), ventral (VS), and anterior (AS) sacs 1h before and 3 h after the morning feeding on two sampling days with a 2-d interval . Irrespective of diet and sampling time, the greatest proportion of entodiniomorphs, representing the main population of protozoa, was found in the DS (40% mean; P < .05) . Low pH values observed in the DS (P < .05) indicated higher fermentative activity in this site than in the other parts of the rumen . Protozoa may contribute more than previously thought to the high digestive potential present at the top of the rumen that has classically been attributed to bacteria . The specific activity of plant cell wall polysaccharide-degrading enzymes in the LAP was correspondingly greater (P < .05) for DS than for VS or AS . For the two diets and sampling times, specific activity of fibrolytic enzymes in the SAB tended to be less in the upper than in the lower parts of the rumen, and less in the VS than in the AS . This tendency became significant (P < .05) for total fibrolytic enzyme activity . Differences in bacterial colonization of particles among the three sampling sites may explain such differences in fibrolytic activity of the SAB . Data suggest a spatio-temporal complementary action of the bacteria and protozoa in ruminal plant cell wall degradation, at least with the barley diet, for which the number of protozoa was highest. Reprod Nutr Dev, 1999 Mar-Apr, 39(2), 255 - 68 Effects of minerals on feed degradation and protein synthesis by rumen micro-organisms in a dual effluent fermenter; Broudiscou LP et al.; In dual outflow continuous fermenters on a 75:25 hay/barley diet, feed degradation and protein synthesis by mixed rumen microbes were tested in relation to the concentrations of HPO4(2-), HCO3- and Cl- and Na+/K+ ratio in artificial saliva, by applying a 16-run Franquart design, and by fitting second-order polynomial models . The HPO4(2-), HCO3-, Cl- concentrations and Na+/K+ ratio ranged from 0.1 to 4 g.L-1, from 0.5 to 7 g.L-1, from 0.1 to 0.5 g.L-1 and from 0.5 to 15 g.g-1, respectively . Buffer salts, particularly HPO4(2-), were the major factors while Cl- concentration had negligible effects on microbial metabolism . Maximal neutral detergent fibre, acid detergent fibre and organic matter degradabilities occurred at intermediate values of HPO4(2-) and HCO3- concentrations . The outflow of microbial protein and the efficiency of microbial protein synthesis, which varied from 26.2 to 37.1 g.N.kg-1 of organic matter truly degraded, reached minima at the centre of the experimental domain. Reprod Nutr Dev, 1999 Mar-Apr, 39(2), 223 - 30 Caecal microflora and fermentation pattern in exclusively milk-fed young rabbits; Padilha MT et al.; Thirty-two SPF New Zealand White rabbits of both sexes were used in this experiment . They were sequentially slaughtered at 22, 29, 35 and 42 days of age . The rabbits were only milked by their mother and by foster mothers (no access to solid food) throughout the experiment . They exhibited a caecal fermentation pattern that turned towards a proteolytic metabolic activity (high levels in NH3 and in branched-chain fatty acids and valeric acid: 17 mmol.L-1 and 1 mmol.L-1, on average, respectively) . The absence of caecal cellulolytic microflora and the low concentration of the total volatile fatty acids (tVFA) could be explained by the lack of substrate that would have been brought by a solid feed . From day 29 onwards, the low tVFA (12.5 mmol.L-1) and high NH3 concentrations (16.5 mmol.L-1) explained the high pH value (6.8 on average) . This could be considered as a pathological value in weaned rabbits, but in our case no clinical signs of diarrhoea were observed . The evolution of the colibacilli flora according to age was similar to that usually described and thus was not correlated with pH, tVFA or cellulolytic flora . The evolution of the colibacilli population (from 10(7) bact/g on day 22 to 10(3) on day 42) seemed dependent on ontogenic factors rather than on the composition of the caecal media (pH, etc.). Wei Sheng Yan Jiu, 1997 Sep, 26(5), 330 - 2 {Experimental studies on the fatigue resistance of fermented morel liquid}; Yun J; The fatigue resistant effect of fermented morel liquid is studied in mice . The results show: fermented morel liquid can remarkably promote the reserve of glycogen in muscle and liver, raise the hemoglobin concentration, reduce the content of blood lactic acid, and greatly enhance the sporting endurance. Wei Sheng Yan Jiu, 1997 Jul, 26(4), 287 - 8, back cover {Effect of fermented morel liquid on immunity function in mice}; Yu Q; The experiments studied the effect of fermented morel liquid on immunity function in mice {correction of rats}.The results showed that fermented morel liquid could greatly enhance the non-specific immunity (macrophage's phagocytosis), specific immunity (delayed-type hypersensitivity), humoral immunity (the amount of hemolysin) and the weights of thymus . The author concluded that the fermented morel liquid could effectively regulate the immunity function in mice {correction of rats}. Int J Syst Bacteriol, 1999 Apr, 49 Pt 2, 639 - 43 Isolation and characterization of Desulfovibrio burkinensis sp . nov . from an African ricefield, and phylogeny of Desulfovibrio alcoholivorans; Ouattara AS et al.; A sulfate-reducing bacterium, strain HDvT (T = type strain), was isolated from an anoxic ricefield soil . Cells were Gram-negative, non-sporulating curved rods motile by means of a single polar flagellum . Cytochrome c3 and desulfoviridin were present . In the presence of sulfate, glycerol, 1,2- and 1,3-propanediol, dihydroxyacetone, pyruvate, lactate, fumarate, maleate, malate and succinate were incompletely oxidized mainly to acetate . Sulfite, thiosulfate, elemental sulfur, fumarate, maleate and malate were utilized as alternative electron acceptors . In the absence of added electron acceptors, pyruvate, fumarate, maleate, malate and dihydroxyacetone were fermented . The DNA base composition was 67 mol% G + C . The phylogenetic, phenotypic and physiological characteristics of strain HDvT indicate that it is a new species of the genus Desulfovibrio, for which the name Desulfovibrio burkinensis sp . nov . is proposed; the type strain is HDvT (= DSM 6830T) . Phylogenetic analysis confirmed that Desulfovibrio alcoholivorans was a distinct species supporting the previously published phenotypic data. Plant Physiol, 1999 May, 120(1), 293 - 300 Membrane lipid integrity relies on a threshold of ATP production rate in potato cell cultures submitted to anoxia Rawyler A, Pavelic D, Gianinazzi C, Oberson J, Braendle R. In this paper we report on our study of the changes in biomass, lipid composition, and fermentation end products, as well as in the ATP level and synthesis rate in cultivated potato (Solanum tuberosum) cells submitted to anoxia stress . During the first phase of about 12 h, cells coped with the reduced energy supply brought about by fermentation and their membrane lipids remained intact . The second phase (12-24 h), during which the energy supply dropped down to 1% to 2% of its maximal theoretical normoxic value, was characterized by an extensive hydrolysis of membrane lipids to free fatty acids . This autolytic process was ascribed to the activation of a lipolytic acyl hydrolase . Cells were also treated under normoxia with inhibitors known to interfere with energy metabolism . Carbonyl-cyanide-4-trifluoromethoxyphenylhydrazone did not induce lipid hydrolysis, which was also the case when sodium azide or salicylhydroxamic acid were fed separately . However, the simultaneous use of sodium azide plus salicylhydroxamic acid or 2-deoxy-D-glucose plus iodoacetate with normoxic cells promoted a lipid hydrolysis pattern similar to that seen in anoxic cells . Therefore, a threshold exists in the rate of ATP synthesis (approximately 10 &mgr;mol g-1 fresh weight h-1), below which the integrity of the membranes in anoxic potato cells cannot be preserved. Am J Gastroenterol, 1999 May, 94(5), 1373 - 80 Rarity of colon cancer in Africans is associated with low animal product consumption, not fiber; O'Keefe SJ et al.; OBJECTIVE: To investigate whether the rarity of colon cancer in black Africans (prevalence, < 1:100,000) can be accounted for by dietary factors considered to reduce risk, and by differences in colonic bacterial fermentation . METHODS: Samples of the adult black South African population were drawn from several rural and urban regions . Food consumption was assessed by home visits, food frequency questionnaires, computerized analysis of 72-h dietary recall, and blood sampling . Colonic fermentation was measured by breath H2 and CH4 response to a traditional meal, and to 10-g of lactulose . Cancer risk was estimated by measurement of epithelial proliferation indices (Ki-67 and BrdU) in rectal mucosal biopsies . Results were evaluated by comparison to measurements in high-risk white South Africans (prevalence, 17:100,000) . RESULTS: Epithelial proliferation was significantly lower in rural and urban blacks than whites . The diets of all the black subgroups were characterized by a low animal product and high boiled maize-meal content, whereas whites consumed more fresh animal products, cheese, and wheat products . Blacks consumed below RDA quantities of fiber (43% of RDA), vitamin A (78%), C (62%), folic acid (80%) and calcium (67%), whereas whites consumed more animal protein (177% of RDA) and fat (153%) . Fasting and food-induced breath methane production was two to three times higher in blacks . CONCLUSIONS: The low prevalence of colon cancer in black Africans cannot be explained by dietary "protective" factors, such as, fiber, calcium, vitamins A, C and folic acid, but may be influenced by the absence of "aggressive" factors, such as excess animal protein and fat, and by differences in colonic bacterial fermentation. Am J Physiol, 1999 May, 276(5 Pt 2), R1265 - 75 Magnitude of functional adaptation after intestinal resection; O'Connor TP et al.; Intestinal adaptation after resection has been much studied, but rarely examined in an integrative context . Hence we assessed the effects of resection and subsequent adaptation on the quantitative relationship between dietary glucose load and gut capacity to transport glucose . The ratio of capacity to load is termed the "safety factor." Our objectives were to determine 1) the time course of intestinal adaptation after resection, 2) whether adaptation is quantitatively complete, 3) whether survival requires maintaining a safety factor of at least 1.0 for glucose transport, 4) the effect of altered energy demands on adaptation, and 5) the relationship between the amount of tissue removed and the magnitude of functional adaptation . We performed 80% resection of the small intestine on Sprague-Dawley rats and measured small intestinal glucose uptake capacity, dietary glucose load, and gut gross morphology at 1, 5, and 10 wk postsurgery . Nearly all aspects of adaptation were complete by 1 wk postsurgery . After resection, remnant small intestine mass increased by over fivefold within 1 wk, to reach 50-70% of its preresection value . However, mass-specific glucose uptake activity was reduced, so that intestinal regeneration restored uptake capacity to only 33% of control values . Increased energetic demands had only modest effects on intestinal adaptation . Although the safety factor for small intestinal glucose uptake remained <1.0 (i.e., capacity < load) after adaptation to resection, nearly all rats survived . Hindgut fermentation of nonabsorbed nutrients appeared to contribute to that survival, despite inadequate small intestinal capacity . After less massive resection surgeries (25, 50, and 75% resections), the percent increase in glucose uptake capacity increased with the amount of tissue removed. Alcohol, 1999 Apr, 17(3), 241 - 5 Fatty acid ethyl ester synthesis in the preparation of scotch whiskey; Goss KA et al.; Fatty acid ethyl esters (FAEE), nonoxidative ethanol metabolites present in human organs commonly damaged by ethanol abuse, have been implicated as mediators of organ damage . FAEE are additives in various foods and beverages to provide flavor or fragrance, and therefore are common dietary lipid constituents . We hypothesized that FAEE could be generated during alcoholic beverage production because fatty acids are present within microorganisms and ethanol is generated during the fermentation process . In this report, we demonstrate that FAEE are present in commercially available scotch beverages, and that in the preparation of scotch, FAEE can be produced during the fermentation reaction as a result of FAEE synthase activity in the yeast . Following ingestion of scotch, preformed FAEE are delivered to GI tract . The consequences of ingestion of FAEE in scotch, if any, remain to be determined. Appl Biochem Biotechnol, 1998 Nov-Dec, 75(2-3), 235 - 48 Importance of growth form on production of hybrid antibiotic by Streptomyces lividans TK21 by fed-batch and continuous fermentation; Sarra M et al.; A fermentation strategy, based on the controlled feeding of growth-limiting nutrients in order to maintain metabolic activity for extended periods, has been examined in the case of the production of a hybrid antibiotic by a transformed strain of Streptomyces lividans TK21 . The fed-batch operation did not improve the results obtained with batch operation . Continuous cultures on defined medium showed stable levels of biomass concentration, but antibiotic production ceased when continuous operation was started . The results obtained indicate the critical influence that morphology of the cell aggregates has on metabolic activity . The antibiotic is produced only in culture conditions providing growth in compact mycelial pellets. Appl Biochem Biotechnol, 1998 Nov-Dec, 75(2-3), 205 - 14 Strategies for reducing solvent toxicity in extractive ethanol fermentation; Kapucu H et al.; Extractive fermentation is a widely preferred technique in which the products of fermentation are removed from the fermentation medium by a proper solvent, in order to avoid the inhibitory effects of the products . In this work, decanol, which has a high distribution coefficient with respect to the biocompatible solvents, was used in extractive ethanol fermentation . In order to reduce decanol toxicity, Saccharomyces cerevisiae cells were immobilized in calcium alginate gel . Further, sunflower oil and Al2O3 were added to the immobilization media . Experiments were performed in 250-mL Erlenmeyer flasks that were placed in the constant-temperature bath of a constant stirring-rate shaker . Ethanol concentrations were measured to observe the effect of various parameters on ethanol production . Immobilization media included 10, 20, and 30% sunflower oil, or 5, 10, and 20% Al2O3, or Al2O3 and sunflower oil together . The ratio of the volume of aqueous phase to that of decanol phase ranged from 2:1 to 6:1 . It was observed that protection depends on the oil, Al2O3, and decanol amounts . Utilization of sunflower oil (30%) and Al2O3 (5%) together yielded best results. Res Microbiol, 1999 Apr, 150(3), 199 - 204 On the origins of wine yeast; Mortimer R et al.; There is still a lack of agreement concerning the relative contribution of wine yeast that may originate in the vineyard compared to that which may originate in the cellar . Part of this controversy is due to the extreme difficulty of finding Saccharomyces cerevisiae on the grapes . We estimate that only about one in one-thousand grape berries carries wine yeast . However, we have found that grape berries that are damaged (i.e . the skin is broken) are very rich depositories of microorganisms including S . cerevisiae, and that one in four such berries is S . cerevisiae-positive . These positive berries have between 100,000 and 1,000,000 wine yeast cells on them, and there is evidence that these yeasts are clonal . We believe that the yeasts are brought to the berries by insects such as bees, wasps, and Drosophila and that they multiply in the rich medium of the grape interior . Even though there are many cells of S . cerevisiae on the damaged berries, they are in a definite minority . All the other organisms that are found in wine fermentations are also present on these berries, and their total numbers are in the range of 10 million to 100 million cells per berry. J Anim Sci, 1999 Mar, 77(3), 780 - 4 Influence of malic acid supplementation on ruminal pH, lactic acid utilization, and digestive function in steers fed high-concentrate finishing diets; Montano MF et al.; Two trials were conducted to evaluate the influence of malic acid supplementation on ruminal fermentation . In Trial 1, six Holstein steers (300 kg) with ruminal cannulas were used in a crossover design experiment to study the influence of malic acid (MA) on ruminal metabolism during glucose-induced lactic acidosis . Treatments consisted of a 77% steam-flaked barley-based finishing diet supplemented to provide 0 or 80 g/d of MA . After a 13-d dietary adjustment period, 1 kg of glucose was infused into the rumen 1 h after the morning feeding . Ruminal pH was closely associated (R2 = .70) with ruminal DL-lactate concentration . Malic acid supplementation increased (P < .01) ruminal pH 3 h after the glucose infusion . However, there were no treatment effects (P > .10) on ruminal VFA molar proportions or ruminal and plasma DL-lactate concentrations . In Trial 2, four Holstein steers (150 kg) with cannulas in the rumen and proximal duodenum were used in a crossover design experiment to evaluate the influence of MA supplementation on characteristics of digestion . Treatments consisted of an 81% steam-flaked barley-based finishing diet supplemented to provide 0 or 80 g/d of MA . There were no treatment effects (P > .10) on ruminal and total tract digestion of OM, ADF, starch, and feed N or on ruminal microbial efficiency . Malic acid supplementation increased (P < .05) ruminal pH 2 h after feeding . As with Trial 1, there were no treatment effects (P > .10) on ruminal VFA and DL-lactate concentrations . We conclude that supplementation of high-grain finishing diets with MA may be beneficial in promoting a higher ruminal pH during periods of peak acid production without detrimental effects on ruminal microbial efficiency or starch, fiber, and protein digestion . There were no detectable beneficial effects of MA supplementation on ruminal and plasma lactic acid concentrations in cattle fed high-grain diets. Microbiol Immunol, 1999, 43(2), 127 - 32 Genetic relationships among mycoplasmas based on the 16S-23S rRNA spacer sequence; Harasawa R; The nucleotide sequences of the spacer regions between the 16S and 23S rRNA genes of 20 Mycoplasma species were determined following amplification by PCR . Although the spacer regions lacked spacer tRNA genes, they contained the box B and box A sequences in this order from the 5' terminus . The sequence alignment indicated that the 20 species were divided into four clusters, the M . pneumoniae, M . hominis, M . hyorhinis and M . fermentans clusters, and a single floating species, M . hyopneumoniae. Br Homeopath J, 1999 Jan, 88(1), 28 - 30 The early work of Dr . Edward Bach; Leary B; The work of Edward Bach, prior to his discovery of the Flower remedies, is described . He demonstrated non-lactose-fermenting bacteria in patients' stools . These were later used as the basis of some of the Bowel Nosodes. J Environ Sci Health B, 1999 May, 34(3), 527 - 47 Anaerobic treatment of poultry mortalities in a modified LB-UASB system; Chen TH; The efficiency of a modified LB-UASB system in treating poultry mortalities was tested . The anaerobic digestion system consisted of an upflow anaerobic sludge blanket (UASB) and three leachbeds (LB) . The LBs were batch-loaded with mortality to be treated . The LBs were sequentially connected to the UASB, one at a time . Leachate from a connected LB was fed to the UASB while effluent from the UASB overflowed to the LB to form a closed loop . When the concentrations of leachate from the first LB became so low that it could no longer support accelerated methanogenesis in the UASB, it was replaced by a second LB containing a new batch of mortality . Concentrated leachate from the second LB allowed the UASB to continue operation at higher loading rates (LR), thus, alleviating the problems of lengthy LR build-up and idling time . Meanwhile, the off-lined LB continued to mature independently . The UASB was connected to a third LB when the second LB entered accelerated methanogenesis phase . Operation of the first LB was stopped when CH4 production rate from it became marginal . The remaining solids material was replaced by a new batch of mortality to start the second cycle . The first cycle was completed when fermentation in the third LB was ended . The modified LB-UASB system performed significantly better than the original system . It took an average of only 86 days to treat one batch of mortality, yet, the methane yield was about 40% higher . The average methane yield was 0.28 m3 (kg wet weight)-1 . Strategies to optimize system performances are discussed. J Environ Sci Health B, 1999 May, 34(3), 397 - 411 Herbicide residues in grapes and wine; Ying GG et al.; The persistence of several common herbicides from grapes to wine has been studied . Shiraz, Tarrango and Doradillo grapes were separately sprayed with either norflurazon, oxyfluorfen, oxadiazon or trifluralin-persistent herbicides commonly used for weed control in vineyards . The dissipation of the herbicides from the grapes was followed for 28 days following treatment . Results showed that norflurazon was the most persist herbicide although there were detectable residues of all the herbicides on both red and white grapes at the end of the study period . The penetration of herbicides into the flesh of the grapes was found to be significantly greater for white grapes than for red grapes . Small-lot winemaking experiments showed that norflurazon persisted at levels close to the initial concentration through vinification and into the finished wine . The other herbicides degraded, essentially via first-order kinetics, within the period of "first fermentation" and had largely disappeared after 28 days . The use of charcoal together with filter pads, or with diatomaceous earth was shown to be very effective in removing herbicide residues from the wine . A 5% charcoal filter removed more than 96% of the norflurazon persisting in the treated wine. Biosci Biotechnol Biochem, 1999 Mar, 63(3), 560 - 2 Breeding of yeast strains able to grow at 42 degrees C; Kawamura D; Saccharomyces cerevisiae strain 2-39/10A is able to ferment alcohol at 42 degrees C . The ability of various yeast strains, including 2-39/10A, to grow at high temperatures was compared . The strain 2-39/10A was able to grow at 42 degrees C and the high temperature growth was found to be governed by more than one gene . The yeast strains that can grow at 42 degrees C were bred by crossing the haploid strains, which are inherently unable to grow at high temperatures. Wien Klin Wochenschr, 1999 Mar 12, 111(5), 207 - 14 A novel mammalian cell (Vero) derived influenza virus vaccine: development, characterization and industrial scale production; Kistner O et al.; Influenza virus for vaccine production are presently produced in embryonated chicken eggs . This conventional standard methodology is extremely cumbersome; it requires a huge amount of eggs and an extensive purification to reduce the amount of contaminating egg proteins and to minimize the risk of allergies against egg albumin . The shortage of eggs in a pandemic situation, the selection of egg-adapted variants and the presence of adventitious viruses has emphasized the necessity for production of influenza vaccines on a well characterized stable cell line . Our established Vero cell technology has been successfully adapted to large scale production of a variety of influenza virus strains . The production in 1200 litre fermenter cultures under serum-free conditions gave antigen yields comparable to the conventional embryonated egg technology . The development of a rapid and efficient purification scheme resulted in a safe high purity vaccine which was at least as immunogenic as conventional egg-derived vaccines in a mouse model . This vaccine has been shown to be safe and highly immunogenic in chimpanzees and to be capable of protecting ferrets against challenge with live virus . Clinical trials have now been initiated in the UK and Austria. Appl Environ Microbiol, 1999 May, 65(5), 2260 - 3 Whey fermentation by anaerobiospirillum succiniciproducens for production of a succinate-based animal feed additive Samuelov NS, Datta R, Jain MK, Zeikus JG. Anaerobic fermentation processes for the production of a succinate-rich animal feed supplement from raw whey were investigated with batch, continuous, and variable-volume fed-batch cultures with Anaerobiospirillum succiniciproducens . The highest succinate yield, 90%, was obtained in a variable-volume fed-batch process in comparison to 80% yield in a batch cultivation mode . In continuous culture, succinate productivity was 3 g/liter/h, and the yield was 60% . Under conditions of excess CO2, more than 90% of the whey-lactose was consumed, with an end product ratio of 4 succinate to 1 acetate . Under conditions of limited CO2, lactose was only partially consumed and lactate was the major end product, with lower levels of ethanol, succinate, and acetate . When the succinic acid in this fermentation product was added to rumen fluid, it was completely consumed by a mixed rumen population and was 90% decarboxylated to propionate on a molar basis . The whey fermentation product formed under excess CO2, which contained mainly organic acids and cells, could potentially be used as an animal feed supplement. Appl Environ Microbiol, 1999 May, 65(5), 2209 - 16 Molecular phylogenetic and biogeochemical studies of sulfate-reducing bacteria in the rhizosphere of spartina alterniflora Hines ME, Evans RS, Sharak Genthner BR, Willis SG, Friedman S, Rooney-Varga JN, Devereux R. The population composition and biogeochemistry of sulfate-reducing bacteria (SRB) in the rhizosphere of the marsh grass Spartina alterniflora was investigated over two growing seasons by molecular probing, enumerations of culturable SRB, and measurements of SO42- reduction rates and geochemical parameters . SO42- reduction was rapid in marsh sediments with rates up to 3.5 &mgr;mol ml-1 day-1 . Rates increased greatly when plant growth began in April and decreased again when plants flowered in late July . Results with nucleic acid probes revealed that SRB rRNA accounted for up to 43% of the rRNA from members of the domain Bacteria in marsh sediments, with the highest percentages occurring in bacteria physically associated with root surfaces . The relative abundance (RA) of SRB rRNA in whole-sediment samples compared to that of Bacteria rRNA did not vary greatly throughout the year, despite large temporal changes in SO42- reduction activity . However, the RA of root-associated SRB did increase from <10 to >30% when plants were actively growing . rRNA from members of the family Desulfobacteriaceae comprised the majority of the SRB rRNA at 3 to 34% of Bacteria rRNA, with Desulfobulbus spp . accounting for 1 to 16% . The RA of Desulfovibrio rRNA generally comprised from <1 to 3% of the Bacteria rRNA . The highest Desulfobacteriaceae RA in whole sediments was 26% and was found in the deepest sediment samples (6 to 8 cm) . Culturable SRB abundance, determined by most-probable-number analyses, was high at >10(7) ml-1 . Ethanol utilizers were most abundant, followed by acetate utilizers . The high numbers of culturable SRB and the high RA of SRB rRNA compared to that of Bacteria rRNA may be due to the release of SRB substrates in plant root exudates, creating a microbial food web that circumvents fermentation. Appl Environ Microbiol, 1999 May, 65(5), 1864 - 70 Production of manganese peroxidase and organic acids and mineralization of 14C-labelled lignin (14C-DHP) during solid-state fermentation of wheat straw with the white rot fungus nematoloma frowardii Hofrichter M, Vares T, Kalsi M, Galkin S, Scheibner K, Fritsche W, Hatakka A. The basidiomycetous fungus Nematoloma frowardii produced manganese peroxidase (MnP) as the predominant ligninolytic enzyme during solid-state fermentation (SSF) of wheat straw . The purified enzyme had a molecular mass of 50 kDa and an isoelectric point of 3.2 . In addition to MnP, low levels of laccase and lignin peroxidase were detected . Synthetic 14C-ring-labelled lignin (14C-DHP) was efficiently degraded during SSF . Approximately 75% of the initial radioactivity was released as 14CO2, while only 6% was associated with the residual straw material, including the well-developed fungal biomass . On the basis of this finding we concluded that at least partial extracellular mineralization of lignin may have occurred . This conclusion was supported by the fact that we detected high levels of organic acids in the fermented straw (the maximum concentrations in the water phases of the straw cultures were 45 mM malate, 3.5 mM fumarate, and 10 mM oxalate), which rendered MnP effective and therefore made partial direct mineralization of lignin possible . Experiments performed in a cell-free system, which simulated the conditions in the straw cultures, revealed that MnP in fact converted part of the 14C-DHP to 14CO2 (which accounted for up to 8% of the initial radioactivity added) and 14C-labelled water-soluble products (which accounted for 43% of the initial radioactivity) in the presence of natural levels of organic acids (30 mM malate, 5 mM fumarate). Carcinogenesis, 1999 Apr, 20(4), 651 - 6 A comparison of the effects of dietary cellulose and fermentable galacto-oligosaccharide, in a rat model of colorectal carcinogenesis: fermentable fibre confers greater protection than non-fermentable fibre in both high and low fat backgrounds; Wijnands MV et al.; The objective of this experiment was to compare the effects of diets with either a non-fermentable fibre source (cellulose) or a fermentable fibre source {galacto-oligosaccharide (GOS)}, combined with different levels of dietary fat, on the development of colorectal cancer . Male Wistar rats were fed AIN76-based diets with either a low or high level of cellulose, or a low or high level of GOS, for 9 months . The fat content of the diets was low, medium or high . All rats were treated with 1,2-dimethylhydrazine to induce colorectal tumours . Generally, the tumour incidence increased with increasing fat content in the diet . Despite marked faeces bulking, dietary cellulose either had no effect or an enhancing effect on the formation of colorectal tumours in general, although the development of carcinomas was decreased . GOS appeared to be highly protective against the development of colorectal tumours, as was demonstrated by an inhibitory effect on tumour incidence, multiplicity and size, regardless of the fat content of the diet . Neither fibre source influenced the bromodeoxyuridine labelling index determined in colon crypts or tumours . In animals fed high-GOS diets, the caecal content was significantly increased in weight and significantly decreased in pH . It was concluded that tumorigenesis was enhanced by increased fat content of the diet, and that the diets containing fermentable GOS conferred a greater protection against colorectal cancer than did the diets containing non-fermentable cellulose. Carcinogenesis, 1999 Apr, 20(4), 629 - 34 Potential of short chain fatty acids to modulate the induction of DNA damage and changes in the intracellular calcium concentration by oxidative stress in isolated rat distal colon cells; Abrahamse SL et al.; Short chain fatty acids (SCFA) are considered to be beneficial fermentation products in the gut by exerting trophic effects in non-transformed colon cells and by slowing proliferation and enhancing differentiation in colonic tumour cells . We have studied the further effects of SCFA on cellular events of early carcinogenesis, genotoxicity and cytotoxicity in rat distal colon cells . Cytotoxicity was assessed by measuring trypan blue exclusion and by determining the H2O2-induced changes in intracellular calcium concentration ({Ca2+}i) using a fluorospectrophotometer and the calcium-sensitive fluorescent dye Fura-2 . The microgel electrophoresis technique (COMET assay) was used to assess oxidative DNA damage . Individual SCFA and physiological SCFA mixtures were investigated for their potential to prevent DNA and cell damage induced by H2O2 . For this, freshly isolated colon cells were treated with H2O2 (100-500 microM) and 6.25 mM SCFA . We have found 100-500 microM H2O2 to cause a fast initial increase in {Ca2+}i, whereafter the levels gradually further increased . Addition of SCFA did not affect {Ca2+}i nor did it reduce the H2O2-induced increase in {Ca2+}i . Butyrate and acetate were able to reduce the induction of DNA damage by 100, 200 and 500 microM H2O2, respectively . In contrast, i-butyrate and propionate were ineffective . The degree of reduction of DNA damage for the two protective SCFA was similar . Physiological mixtures containing acetate, propionate and butyrate in ratios of 41:21:38 or 75:15:10 that are expected to arise in the colon after fermentation of resistant starches and pectin, respectively, did not show significant antigenotoxic effects . The major difference between butyrate and acetate, on one hand, and i-butyrate and propionate, on the other hand, is that the former compounds are utilized best as energy sources by the colon cells . Therefore, our results on antigenotoxicity coupled with the findings on {Ca2+}i homeostasis indicate that molecular effects on the energy system render these non-transformed, freshly isolated colon cells to be less susceptible to H2O2. Med Dosw Mikrobiol, 1998, 50(3-4), 179 - 96 {Characteristics of E.coli O157 strains isolated in Poland from clinical material and food samples}; Szych J et al.; E . coli belonging to the O157 serological group are among the organisms isolated most frequently out of all the so called entero-hemorrhagic E . coli strains (EHEC) . Since several years they have been isolated also in Poland . The purpose of the present study was determination on selected phenotypic and genotypic properties of E . coli O157 strains isolated in our country from clinical material samples and from food . The serotype of the strains was determined, together with the following properties regarded as pathogenicity markers of verotoxic E . coli strains such as absence of beta-glucuronidase activity and sorbitol fermentation ability, as well as production of verotoxins SLT I and/or SLT II and entero-hemolysin . Besides that, by the PCR method the fragments of the genes coding for verotoxins, intimin and enterohaemolysin were amplified . The products of PCR were analysed by the restriction enzyme analysis (RFLP) . All verotoxic E . coli O157 strains isolated in Poland were analysed by the pulsed field gel electrophoresis of genomic DNA (PFGE) . The studied group comprised E . coli O157 strains, among them 40 strains were isolated from human faeces and 5 from food . The remaining strains were the reference E . coli O157:H7 EDL 933 and G 5244 strains and strains from NIH collection . The obtained results showed that the tested strains were a very varying population . 21 of them (all isolated from food, 11 from faeces and 5 reference strains) belonged to serotype O157:H7, five were not peritrichous O157:NM and the remaining ones had other ciliary antigen than H7 . All strains isolated from food, reference strains and only 3 O157:NM strains isolated from humans were verotoxic . The strains from food and two reference strains produced only SLT II, 2 of 3 strains isolated from humans and one reference strain also produced only SLT II and the other produced both verotoxins . Apart from these 13 verotoxic strains all remaining strains caused sorbitol fermentation. Appl Microbiol Biotechnol, 1999 Mar, 51(3), 310 - 5 Influence of microbial concentration on the rheology of non-Newtonian fermentation broths; Goudar CT et al.; The objective of this study was to quantify the effect of fungal biomass concentration on the rheology of non-Newtonian fermentation systems . Batch fermentations of Penicillium chrysogenum were carried out with glucose as the sole carbon source . The flow behavior of the system was characterized at various fermentation times and was adequately described by the power-law model . The apparent viscosity of the fermentation broth was significantly affected by biomass concentrations in the fermenter . Fermentation broths containing 17.71 g/l biomass as dry weight were characterized by an apparent viscosity of 0.25 Pa s at a shear rate of 50 s-1 . Microbial concentration also affected the power-law flow-behavior index and the consistency index . The value of the consistency index ranged from 0.002 Pa sn at a biomass concentration of 0.1 g/l to 6.14 Pa sn at a biomass concentration of 17.71 g/l . The flow-behavior index decreased from an initial value of 1 to a final value of 0.17 . Simple empirical correlations have been proposed to quantify the dependence of the power-law parameters on fungal biomass concentration . Experimental data obtained in this study were accurately described by these correlations . The general applicability of these relationships was tested, using previously published rheological data on Aspergillus awamori and Aspergillus niger fermentation broths, and good agreement was seen between experimental data and the predictions from the empirical correlations. J Nutr, 1999 May, 129(5), 942 - 8 Short-chain fatty acids suppress cholesterol synthesis in rat liver and intestine; Hara H et al.; We previously showed that plasma cholesterol levels decreased following ingestion of a short-chain fatty acid (SCFA) mixture composed of sodium salts of acetic, propionic, and butyric acids simulating cecal fermentation products of sugar-beet fiber (SBF) . In the present study, we investigated whether hepatic and small intestinal cholesterol synthesis is involved in the cholesterol-lowering effects of SCFA and SBF . In vitro (expt . 1) and in vivo (expt . 2) cholesterol synthesis rates and the diurnal pattern of SCFA concentrations in portal plasma (expt . 3) were studied in three separate experiments in rats fed diets containing the SCFA mixture, SBF (100 g/kg diet), or the fiber-free control diet . Cholesterol synthesis was measured using 3H2O as a tracer . The in vitro rate of cholesterol synthesis, measured using liver slices, was greater in the SBF group, but not in the SCFA group, than in the fiber-free control group . In contrast, the hepatic cholesterol synthesis rate in vivo was lower in the SCFA group, but not in the SBF group, than in the control group . The mucosal cholesterol synthesis rate for the whole small intestine was <50% of the hepatic rate . The rate in the proximal region was slightly but significantly lower in the SCFA group, and was significantly higher in the SBF group than in the fiber-free group . The rate in the distal small intestines was also significantly greater in the SBF group than in the fiber-free group . Plasma total cholesterol concentrations were lower in the SCFA and SBF groups than in the fiber-free group in both experiments 2 and 3 . Diurnal changes in portal SCFA and cholesterol levels were studied in the experiment 3 . SCFA concentrations increased rapidly after the start of feeding the SCFA diet, and changes in plasma cholesterol were the reciprocal of those observed in SCFA . These results show that a decrease in hepatic cholesterol synthesis rate mainly contributes to the lowering of plasma cholesterol in rats fed the SCFA mixture diet . Changes in portal SCFA and cholesterol concentrations support this conclusion . In SBF-fed rats, SCFA produced by cecal fermentation are possibly involved in lowering plasma cholesterol levels by negating the counteractive induction of hepatic cholesterol synthesis caused by an increase in bile acid excretion. Yeast, 1999 Mar 30, 15(5), 409 - 17 Isolation and characterization of the ATF2 gene encoding alcohol acetyltransferase II in the bottom fermenting yeast Saccharomyces pastorianus; Yoshimoto H et al.; The ATF2 gene encodes alcohol acetyltransferase II, which catalyses the synthesis of isoamyl acetate from acetyl coenzyme A and isoamyl alcohol . To characterize the ATF2 gene from the bottom fermenting yeast Saccharomyces pastorianus, the S . pastorianus ATF2 gene was cloned by colony hybridization using the S . cerevisiae ATF2 gene as a probe . When an atf1 null mutant strain was transformed with a multi-copy plasmid carrying the S . pastorianus ATF2 gene, the AATase activity of this strain was increased by 2.5-fold compared to the control . The S . pastorianus ATF2 gene has 99% nucleic acid homology in the coding region and 100% amino acid homology with the S . cerevisiae ATF2 gene . Southern blot analysis of chromosomes separated by pulse-field gel electrophoresis indicated that the ATF2 gene probe hybridized to chromosome VII in S . cerevisiae and to the 1100 kb chromosome in S . pastorianus . As S . pastorianus is thought to be a hybrid of S . cerevisiae and S . bayanus, the S . bayanus-type gene, which has a relatively low level of homology with the S . cerevisiae-type gene, is also usually detected . Interestingly, an S . bayanus-type ATF2 gene could not be detected . These results suggested that the cloned ATF2 gene was derived from S . cerevisiae . Analysis using an ATF2-lacZ fusion gene in S . pastorianus showed that expression of the ATF2 gene was relatively lower than that of the ATF1 gene and that it is repressed by aeration but activated by the addition of unsaturated fatty acids . The S . pastorianus ATF1, Lg-ATF1 and ATF2 Accession Numbers in the DDBJ Nucleotide Sequence Database are D63449, D63450 and D86480, respectively. Oral Microbiol Immunol, 1999 Apr, 14(2), 98 - 103 Actinobacillus actinomycetemcomitans serotype e--biotypes, genetic diversity and distribution in relation to periodontal status; Dogan B et al.; Actinobacillus actinomycetemcomitans isolates from 356 individuals were screened for identification of serotype e in order to investigate its distribution in relation to periodontal status . From subjects with serotype e, 1-6 isolates per subject (n = 61) were genotyped using arbitrarily primed-polymerase chain reaction (AP-PCR) and apaH gene polymerase chain reaction-restriction fragment-length polymorphism (PCR-RFLP) analysis to determine the genetic heterogeneity within the serotype . Furthermore, one serotype e strain per subject was tested for fermentation of 8 carbohydrates for biotyping . Among patients with adult periodontitis (n = 219), localized juvenile periodontitis (n = 55) and other forms of early-onset periodontitis (n = 18) serotypes b, a and c, respectively, were the most frequently detected serotypes . Non-periodontitis subjects (n = 64) were predominantly colonized with serotype c . Serotype e was found in 30 (14%) adult periodontitis patients, 2 (11%) early-onset periodontitis patients and in 5 (8%) non-periodontitis individuals, but in none of the 55 localized juvenile periodontitis patients . AP-PCR distinguished 3 and apaH gene PCR-RFLP analysis 2 genotypes among the 61 A . actinomycetemcomitans serotype e isolates, one genotype per subject . The AP-PCR genotypes 1 and 3 represented the apaH genotype 1 and the AP-PCR genotype 2 the apaH genotype 2 . On the basis of variable fermentation of galactose and xylose, 3 biotypes among A . actinomycetemcomitans serotype e were established . Contrary to the absence of A . actinomycetemcomitans serotype e in localized juvenile periodontitis patients, its detection frequency was comparable among other forms of periodontitis and periodontal health . Clinical serotype e isolates form at least 2 genetic types and 3 biotypes. J Dairy Sci, 1999 Apr, 82(4), 780 - 7 Effect of the addition of fumarate on methane production by ruminal microorganisms in vitro; Asanuma N et al.; The effect of fumarate used as a feed additive on the reduction of methanogenesis in the rumen was evaluated by in vitro experiments . The addition of fumarate to the culture of mixed ruminal microorganisms that were fermenting hay powder and concentrate reduced methane production . Most fumarate was metabolized to propionate, and a slight increase was noted in other volatile fatty acids . Fumarate was utilized by mixed bacteria but not by mixed protozoa . Fibrobacter succinogenes, Selenomonas ruminantium ssp . ruminantium, Selenomonas ruminantium ssp . lactilytica, Veillonella parvula, and Wollinella succinogenes oxidized H2 by using fumarate as a final electron acceptor, suggesting that these bacteria compete with methanogens for H2, which is the main substrate for methanogenesis in the rumen . However, the affinity of these bacteria to H2 was lower than their affinity to methanogens . These fumarate-utilizing bacteria metabolized malate to products that were similar to those from fumarate, suggesting the possession of fumarate dehydratase . Fibrobacter succinogenes, V . parvula, and W . succinogenes utilized formate, another substrate for methanogenesis, as an electron donor for fumarate reduction . The affinity of these bacteria to formate was higher than the affinity methanogenes have for formate . When methanogens were cocultured with an equal cellular amount of each of the fumarate-utilizing bacteria, methane production was markedly decreased, not only from formate, but also from H2 . These results suggest that the addition of fumarate to ruminant feed reduces methanogenesis and enhances propionate production in the rumen. J Dairy Sci, 1999 Apr, 82(4), 756 - 63 Predicting the effect of proteolysis on ruminal crude protein degradation of legume and grass silages using near-infrared reflectance spectroscopy; Hoffman PC et al.; Two studies were conducted to assess whether routine applications of near infrared reflectance spectroscopy could predict the effects of silage proteolysis on ruminal crude protein (CP) degradation of legume and grass silages . A preliminary study was conducted to assess the effect of laboratory drying method on ruminal CP degradation of silages . Thirty legume and grass silages were freeze-, oven-, or microwave-dried and incubated in situ in the ventral rumen of three ruminally cannulated cows for 24 h . Freeze-drying was considered least likely to alter ruminal CP degradation of the silages; therefore, oven- and microwave-drying were compared using first-order regression with freeze-drying . Oven-drying for 48 h at 55 degrees C compared favorably (R2 = 0.84) with freeze-drying . Microwave-drying resulted in a large bias (2.84 g/10(-1) kg of CP) and was poorly related (R2 = 0.48) to freeze-drying . In a second study, alfalfa and timothy were cut at three maturities and allowed to wilt for 0, 10, 24, 32, 48, and 54 h . Forages were ensiled in triplicate cylindrical mini silos and allowed to ferment for 120 d . After fermentation, silages were oven-dried, ground, and scanned on a near-infrared reflectance spectrophotometer . Duplicate, dried, 2-mm ground silage samples were incubated in the ventral rumen of three ruminally cannulated cows for 24 h . Forage species, maturity, and wilting time significantly affected 24-h ruminal CP degradation of the silages . Near-infrared reflectance spectroscopy accurately predicted (R2 = 0.91) 24-h ruminal CP degradation of silages . Data suggest near-infrared reflectance spectroscopy can accurately assess the effects of forage species, maturity, and wilting time (proteolysis) on 24-h ruminal CP degradation of legume and grass silages. Yeast, 1999 Mar 15, 15(4), 329 - 50 Transcript analysis of 250 novel yeast genes from chromosome XIV; Planta RJ et al.; The European Functional Analysis Network (EUROFAN) is systematically analysing the function of novel Saccharomyces cerevisiae genes revealed by genome sequencing . As part of this effort our consortium has performed a detailed transcript analysis for 250 novel ORFs on chromosome XIV . All transcripts were quantified by Northern analysis under three quasi-steady-state conditions (exponential growth on rich fermentative, rich non-fermentative, and minimal fermentative media) and eight transient conditions (glucose derepression, glucose upshift, stationary phase, nitrogen starvation, osmo-stress, heat-shock, and two control conditions) . Transcripts were detected for 82% of the 250 ORFs, and only one ORF did not yield a transcript of the expected length (YNL285w) . Transcripts ranged from low (62%), moderate (16%) to high abundance (2%) relative to the ACT1 mRNA . The levels of 73% of the 206 chromosome XIV transcripts detected fluctuated in response to the transient states tested . However, only a small number responded strongly to the transients: eight ORFs were induced upon glucose upshift; five were repressed by glucose; six were induced in response to nitrogen starvation; three were induced in stationary phase; five were induced by osmo-stress; four were induced by heat-shock . These data provide useful clues about the general function of these ORFs and add to our understanding of gene regulation on a genome-wide basis. Yeast, 1999 Mar 15, 15(4), 285 - 93 Yeast vitality during cider fermentation: assessment by energy metabolism; Dinsdale MG et al.; In an apple juice-based medium, an ethanol-tolerant Australian wine-yeast used for cider manufacture produced more than 10% ethanol over a 5 week period . Growth of the inoculum (10(6) organisms ml(-1)) occurred to a population of 3.1 x 10(7) ml(-1) during the first few days; at the end of the fermentation only 5 x 10(5) yeasts ml(-1) could be recovered as colony-forming units on plates . Respiratory and fermentative activities were measured by mass spectrometric measurements (O2 consumption and CO2 and ethanol production) of washed yeast suspensions taken from the cider fermentation at intervals . Both endogenous and glucose-supported energy-yielding metabolism declined, especially during the first 20 days . Levels of adenine nucleotides also showed decreases after day 1, as did adenylate energy charge, although in a prolonged (16.5 week) fermentation the lowest value calculated was 0.55 . AMP was released into the medium . 31P-NMR spectra showed that by comparison with aerobically grown yeast, that from the later stages of the cider fermentation showed little polyphosphate . However, as previously concluded from studies of 'acidification power' and fluorescent oxonol dye exclusion (Dinsdale et al., 1995), repitching of yeast indicated little loss of viability despite considerable loss of vitality. Lett Appl Microbiol, 1999 Feb, 28(2), 142 - 4 Improvement of tylosin fermentation by mutation and medium optimization; Lee SH et al.; A tylosin-hyperproducing mutant of Streptomyces fradiae MNU20 was isolated from 3500 strains obtained from either MNNG- or u.v.-treated S . fradiae NRRL2702 . With the optimal medium, S . fradiae MNU20 was able to produce 159 mg tylosin g biomass(-1), indicating the tylosin productivity in S . fradiae NRLL2702 was increased 14-fold by mutation and medium optimization . When the effect of valine, succinate and natural zeolite on tylosin production was investigated sing the optimal medium, these substances essentially enhanced tylosin production up to 349 mg g biomass(-1); their time addition during the culture period appeared to be critical for the increase. Trends Biotechnol, 1999 Apr, 17(4), 155 - 62 Applying neural networks as software sensors for enzyme engineering; Linko S et al.; The on-line control of enzyme-production processes is difficult, owing to the uncertainties typical of biological systems and to the lack of suitable on-line sensors for key process variables . For example, intelligent methods to predict the end point of fermentation could be of great economic value . Computer-assisted control based on artificial-neural-network models offers a novel solution in such situations . Well-trained feedforward-backpropagation neural networks can be used as software sensors in enzyme-process control; their performance can be affected by a number of factors. J Clin Microbiol, 1999 May, 37(5), 1617 - 8 Septicemia caused by dysgonic fermenter 3 in a severely immunocompromised patient and isolation of the same microorganism from a stool specimen; Grob R et al.; Dysgonic fe