Fermentations

Mutat Res, 1995 Feb, 341(4), 255 - 63
A pharmacokinetic study of ethanol inhibition of micronuclei induction by urethane in mouse bone marrow erythrocytes; Choy WN et al.; Urethane (ethyl carbamate) is a genotoxic carcinogen in fermented products and alcoholic beverages . The genotoxicity of urethane requires metabolic activation . Metabolism of urethane is mediated by multiple pathways, and ethanol is known to inhibit the esterase hydrolysis pathway of urethane, which accounts for over 95% of urethane metabolism . This report shows that ethanol also inhibits the induction of micronuclei by urethane in mouse bone marrow erythrocytes, presumably by inhibiting the minor pathway that generates genotoxic metabolite(s) . In this study, male CD-1 mice were administered urethane, ethanol, or urethane co-administered with increasing amounts of ethanol in single intraperitoneal injections . Bone marrow polychromatic erythrocytes (PCE) obtained 24 h after injection were scored for micronuclei . The dose of urethane was 1000 mg/kg, and the doses of ethanol were 0, 625, 1250, 2000, 2250, 2500, 3000 and 3500 mg/kg . The blood ethanol level at each dose was determined . Two pharmacokinetic parameters, Cmax and AUC, were estimated for each dose . The observed Cmax of ethanol at doses of 1250, 2000, 2250, 2500, 3000 and 3500 mg/kg were 1.39, 2.84, 3.15, 3.69, 4.13 and 4.76 mg/ml, with AUCs of 1.37, 4.84, 5.88, 7.28, 10.76 and 13.51 mg.h/ml, respectively . Urethane treatment alone markedly increased the micronucleus frequency from 0.1% in the vehicle control to 2.47% . This magnitude of increase was suppressed when urethane was co-administered with ethanol at ethanol doses of 2500 mg/kg and above . At 2500, 3000 and 3500 mg/kg, the micronucleus frequencies reduced from 2.47% to 0.9, 0.44 and 0.28%, respectively . This study shows that ethanol inhibits the induction of micronuclei by urethane.

J Biotechnol, 1995 Jan 31, 38(3), 229 - 41
Effective production of the hepatitis C virus core antigen having high purity in Escherichia coli; Seki M et al.; The amino-terminal half of putative nucleocapsid (core) protein (amino acids 1-115) of hepatitis C virus (HCV) was directly overproduced in Escherichia coli under the control of the tac promoter . Overproduction of core antigen was achieved by inserting several target genes and by optimizing the culture conditions, whereas a large amount of directly expressed and purified core antigen has not yet been reported . Although the level of expression was comparable to that of the conventional E . coli fused expression system, our recombinant proteins contain only HCV amino acid sequence . Using recombinant E . coli, overproduced large-scale culture system was achieved in jar-fermenter . A highly purified sample of the expressed protein was obtained by ion-exchange and gel permeation column chromatography in the presence of 8 M urea . From a 3.5 l culture, approximately 440 mg of recombinant core protein was obtained after a two-step purification procedure . An enzyme-linked immunosorbent assay developed using the highly purified antigen satisfactorily diagnosed hepatitis C.

Int J Cancer, 1995 Jan 27, 60(3), 400 - 6
Apoptosis in colorectal tumour cells: induction by the short chain fatty acids butyrate, propionate and acetate and by the bile salt deoxycholate; Hague A et al.; The short chain fatty acids acetate, propionate and butyrate are produced when dietary fibre is fermented by the colonic bacteria . We have previously shown that sodium butyrate induces apoptosis in 3 colorectal tumour cell lines . We have extended our study to 3 adenoma and 4 carcinoma cell lines and investigated whether propionate and acetate also induce apoptosis . All 3 short chain fatty acids induced apoptosis at physiological concentrations, but of the 3, butyrate was the most effective . Since these fatty acids are produced as a result of bacterial fermentation of dietary fibre, this may in part explain the correlation between a high-fibre diet and low colorectal cancer incidence . Sodium butyrate induced apoptosis in all 7 of the cell lines studied; however, 2 of the 4 carcinoma cell lines (PC/JW/FI and S/KS/FI) were more resistant to butyrate-induced apoptosis than the 3 adenoma cell lines, suggesting that at least some carcinomas may evolve mechanisms to protect the cells from the induction of apoptosis . The bile acid deoxycholic acid has previously been reported as a possible tumour promoter in the large intestine and its levels are reduced by dietary fibre . Concentrations of between 10 nM and 0.1 mM had no effect on either the proliferation or apoptosis of colonic tumour cells in vitro . However, a significant induction of apoptosis was obtained at a concentration of 0.5 mM . These results may have significance for the aetiology of colorectal cancer.

Eur J Biochem, 1995 Jan 15, 227(1-2), 270 - 6
Disulfide bonds and glycosylation in fungal peroxidases; Limongi P et al.; Four conserved disulfide bonds and N-linked and O-linked glycans of extracellular fungal peroxidases have been identified from studies of a lignin and a manganese peroxidase from Trametes versicolor, and from Coprinus cinereus peroxidase (CIP) and recombinant C . cinereus peroxidase (rCIP) expressed in Aspergillus oryzae . The eight cysteine residues are linked 1-3, 2-7, 4-5 and 6-8, and are located differently from the four conserved disulfide bridges present in the homologous plant peroxidases . CIP and rCIP were identical in their glycosylation pattern, although the extent of glycan chain heterogeneity depended on the fermentation batch . CIP and rCIP have one N-linked glycan composed only of GlcNAc and Man at residue Asn142, and two O-linked glycans near the C-terminus . The major glycoform consists of single Man residues at Thr331 and at Ser338 . T . versicolor lignin isoperoxidase TvLP10 contains a single N-linked glycan composed of (GlcNAc)2Man5 bound to Asn103, whereas (GlcNAc)2Man3 was found in T . versicolor manganese isoperoxidase TvMP2 at the same position . In addition, mass spectrometry of the C-terminal peptide of TvMP2 indicated the presence of five Man residues in O-linked glycans . No phosphate was found in these fungal peroxidases.

Gene, 1995 Jan 11, 152(1), 107 - 12
Gene MRP-L4, encoding mitochondrial ribosomal protein YmL4, is indispensable for proper non-respiratory cell functions in yeast; Graack HR et al.; In order to characterize individual protein components of the mitochondrial (mt) ribosome for regulatory, functional and evolutionary studies, the yeast nuclear gene MRP-L4 (accession No . Z30582), coding for the mt ribosomal protein (MRP) YmL4, has been cloned using oligodeoxyribonucleotides (oligos) deduced from a partial amino acid (aa) sequence {Graack et al., FEBS Lett . 242 (1988) 4-8} as screening probes . MRP-L4 is located on chromosome XII and codes for a slightly basic protein of 319 aa . The first 14 aa have not been found in the mature protein, and putatively form a signal peptide that is cleaved off during or after mt import . YmL4 has an N terminus very rich in Pro residues, and at its C terminus contains four hydrophobic domains . YmL4 shows no significant sequence similarity to any other sequence from the databases . Gene disruption shows the MRP-L4 product to be indispensable for mt function in cells growing on non-fermentable carbon sources . In contrast to nearly all other MRPs investigated so far, gene disruption of MRP-L4 also affects growth of yeast cells on fermentable carbon sources, suggesting additional cytosolic and/or mt functions of YmL4 besides its involvement in mt protein biosynthesis.

FEBS Lett, 1995 Jan 3, 357(2), 145 - 8
Identification of glutamate beta 54 as the covalent-catalytic residue in the active site of glutaconate CoA-transferase from Acidaminococcus fermentans; Mack M et al.; In the course of glutamate fermentation by Acidaminococcus fermentans glutaconate coenzyme A-transferase catalyzes the transfer of CoAS- from acetyl-CoA to (R)-2-hydroxyglutarate, forming (R)-2-hydroxyglutaryl-CoA . Glutamate (E) 54 of the beta-subunit was postulated to be directly involved in catalysis by formation of a CoASH ester intermediate {(1994) Eur . J . Biochem., in press} . In order to prove this preliminary result, the following mutations, beta E54A, beta E64A, beta E54Q and beta E54D, were introduced by mismatch oligonucleotide priming . As expected, beta E54A was inactive (0.02% of the wild-type), whereas beta E64A and beta E54D were active, 30% and > 7%, respectively . However, no CoASH intermediate was detected in the latter mutant, indicating a change in the catalytic mechanism . The activity of the beta E54Q mutant increased from 1% to almost 100% upon incubation with acetyl-CoA and glutaconate at 37 degrees C within 40 h . Hence, the substrates induced the conversion of the mutant glutamine residue into the glutamate residue of the wild-type enzyme.

FEBS Lett, 1995 Jan 2, 357(1), 70 - 4
The high potential iron-sulfur protein (HiPIP) from Rhodoferax fermentans is competent in photosynthetic electron transfer; Hochkoeppler A et al.; The functional role of the High Potential Iron-sulfur Protein (HiPIP) from the photosynthetic bacterium Rhodoferax fermentans was investigated . We demonstrated that the HiPIP increased the rate of light-induced oxygen reduction mediated by the photosynthetic reaction center (RC); this stimulation reached half-saturation at {HiPIP}/{RC} ca . 15 . The capability of the HiPIP in delivering electrons to the reaction center of Rhodoferax fermentans was demonstrated through kinetic spectrophotometry of cytochrome c-556 oxidation in the presence or in the absence of HiPIP . It is concluded that the HiPIP is competent in the photosynthetic electron transfer chain of Rhodoferax fermentans.

J Environ Pathol Toxicol Oncol, 1995, 14(3-4), 133 - 57
Yeasts: from genetics to biotechnology; Russo S et al.; Yeasts have been known and used in food and alcoholic fermentations ever since the Neolithic Age . In more recent times, on the basis of their peculiar features and history, yeasts have become very important experimental models in both microbiological and genetic research, as well as the main characters in many fermentative production processes . In the last 40 years, advances in molecular biology and genetic engineering have made possible not only the genetic selection of organisms, but also the genetic modification of some of them, especially the simplest of them, such as bacteria and yeasts . These discoveries have led to the availability of new yeast strains fit to fulfill requests of industrial production and fermentation . Moreover, genetically modified and transformed yeasts have been constructed that are able to produce large amounts of biologically active proteins and enzymes . Thus, recombinant yeasts make it easier to produce drugs, biologically active products, diagnostics, and vaccines, by inexpensive and relatively simple techniques . Yeasts are going to become more and more important in the "biotechnological revolution" by virtue of both their features and their very long and safe use in human nutrition and industry.

Yi Chuan Xue Bao, 1995, 22(6), 487 - 93
{Analysis of genetic properties of meiotic products from an interspecific triploid fusion-hybrid itself constructed by protoplast fusion in Saccharomvces}; Li T et al.; A genetically stable interspecific triploid fusion-hybrid between a diploid Saccharomyces cerevisiae var . ellopsoideus and a haploid Saccharomyces diastaticus was constracted by protoplast fusion technique . Experimental results indicate that such hybrid can be induced to sporulate as a sexual hybrid . Genetic analysis of the complete and non-complete tetrads demonstrates that the prototrophic interspecific triploid fusion-hybrid HU-KDF-240 selected by nutritional complementation experienced segregation and exchange for the genetic markers, and showed parental ditype and recombination in the meiotic process of sporulation . The results of the tetrad analysis of the hybrid HU-KDF-240 showed a 1:2 segregation ratio for soluble starch fermenting and non-fermenting characters and a 1:1 segregation ratio for genetic markers of the auxotrophic character in 349 complete and non-complete tetrads from 186 asci of the hybrid.

Nucleic Acids Symp Ser, 1995, (34), 49 - 50
Synthesis and NMR applications of isotopically labeled 2'-deoxynucleosides . Stereospecific deuteration of the C2' methylene in {ul-11 C/15N}deoxyadenosine; Kurita J et al.; Stereospecific deuteration of the C2' methylenes of 2'-deoxynucleosides together with 13C label has been found to open up various applications for structural studies of DNA oligomers in solution . Major problems in analyzing the structure and dynamics of larger DNA oligomers by NMR are associated with geminal proton pairs attached to the C2' and C5' of sugar moieties . We have employed, with a minor modification, existing synthetic routes to prepare stereospecific deuteration of the C2' methylene to prepare 13C/2H-doubly labeled nucleosides . For example, {ul-13C/15N} adenosine, which was prepared by microbial fermentation using {13C6}-glucose and {15N}-ammonium salt as precursors, was derived into (2'R)- and (2'S)-{ul-13C/15N;2'-2H1}-2'-deoxy-adenosines . Each of these multiply labeled nucleosides was then incorporated into a DNA dodecamer, 5'-d(CGCG AATTCGCG)-3', which was examined by various NMR techniques in order to evaluate the precision and accuracy of the NMR parameters obtained for the labeled moieties.

Acta Microbiol Immunol Hung, 1995, 42(4), 331 - 8
Lactic acid production from molasses by Sporolactobacillus cellulosolvens; Kanwar SS et al.; Sporolactobacillus cellulosolvens (NCIMB 12173) isolated from an anaerobic digester and characterised biochemically is being reported for homofermentative lactic acid production from molasses in a batch culture . The effect of various process parameters on lactic acid production were optimized . A maximum lactic acid (24.2 g/l) and yield coefficient (0.79) was achieved using 3% (v/v) inoculum of 36 h old culture in molasses medium containing sugars (5%; w/v) supplemented with peptone (2.5 g/l) and (NH4)2SO4 (7.5 g/l), pH 6.5 at 40 degrees C after 72 h of fermentation.

Verh K Acad Geneeskd Belg, 1995, 57(6), 459 - 525
{Louis Pasteur (1822-1895) . A century later}; Janssens PG; An overview of the amazing series of successive and diverse items worked on by the chemist and physicist Pasteur starts with the asymmetry of paratartrates, switches over to the fermentations and ends in the fight against diseases of invertebrates and vertebrates, including man . It is the wonderful story of an exceptional contribution to the advancement of knowledge, which was made possible by his keen observation skill, his rigorous and innovative methods and his careful judgement . A retrospective analysis of the inner man may impair somewhat the fame of Pasteur . He was a lonely man, in need of solitude to be able to make full use of his thinking capacity, foreboding secretiveness and shrewdness , which are contradictory to his careful writing down day after day of all the details of his thinking and research in his notebooks by now available to the scientific community . He was furthermore selfish, domineering, inflexible, impulsive and inclined to engage in endless controversies . But on the contrary his motivation to accept new assignments was subordinate to their public welfare value and as a rule he endeavoured to work on the problems in the field and in association with those concerned . He was courageous when struck by a cerebral hemorrhage at middle age, so that its aftermath hardly hampered his research activities . The dimness cast on his personality is not up to his pioneer role within a general conservative climate among the medical and even scientific profession, antagonistic to innovation . Pasteur has been a founder of stereochemistry, microbiology and its applications, immunology, bacterial vaccines, pasteurisation and a promotor of prevention and hygiene . These overwhelming achievements justify to keep alive the recognition of the outstanding stature of Pasteur.

J Enzyme Inhib, 1995, 9(4), 277 - 84
Belactins A and B, new serine carboxypeptidase inhibitors produced by Actinomycete . II . Physico-chemical properties, structure determinations and enzymatic inhibitory activities compared with other beta-lactone containing inhibitors; Murakami S et al.; Belactins A and B, new inhibitors of serine carboxypeptidase were discovered in the fermentation broth of Saccharopolyspora sp . MK19-42F6 . The structures of belactins A and B were determined to be 4-{3-{(2-amino-5-chlorobenzoyl)amino}-1,1-dimethyl-2-oxobutyl}-3- methyl-2-oxetanone and 4-{3-{{2-(beta-glucopyranosylamino)-5-chlorobenzoyl}amino}-1,1- dimethyl-2-oxobutyl}-3-methyl-2-oxetanone respectively by various spectral analyses . Belactins A and B do not inhibit esterase or lipase at 100 micrograms/ml but have more specific inhibitory activities towards carboxypeptidase Y (CP-Y) compared with other beta-lactone-containing inhibitors, such as ebelactones A, B and esterastin.

Ann Biol Clin (Paris), 1995, 53(6), 339 - 42
{Rapid assay of plasma acetate by gas chromatography: evaluation and comparison with two other methods}; Boussairi A et al.; Human plasma acetate is derived from colonic fermentation of fiber and endogenous metabolism of dextrose and fatty acids . Acetate may have regulatory functions in hepatic carbohydrate metabolism . Intake of dietary fiber is associated with several beneficial effects on carbohydrates and lipids metabolisms . To study theses effects a valid and automated method for routine analysis of acetate in plasma is necessary . After oral administration of lactulose to healthy human volunteers, the concentration of plasma acetate was measured by head space gas chromatography (HS-GC), vacuum distillation gas chromatography (VD-GC) and enzymatic spectrometric method (ES) . The method HS-GC was linear to 0.5 mmol.l-1 (n = 5, r = 0.998), the detection limit is 0.005 mmol.l-1 . Within-day variation (CV) was 3.60% and day-to-day variation was 4.5% (0.1 mmol.l-1) . The coefficients of correlation between CG-ET/CG-DsV and CG-ET/E-M are 0.903 (p = 0.0001) and 0.54 (p = 0.006) respectively, the mean square errors are respectively 0.118 and 0.138 mmol.l-1 . The variation curves of plasma acetate measured by GC versus time show peak concentration of 0.323 to 0.380 mmol.l-1 at 120 min.

Microbios, 1995, 83(336), 191 - 8
Utilization of water hyacinth cellulose for production of cellobiase-rich preparation by Aspergillus niger 1; Ismail AM et al.; Production of a cellobiase-rich preparation by Aspergillus niger 1 was achieved using water hyacinth cellulose as the sole carbon source in the culture medium . Production of cellobiase, carboxymethylcellulase (CMC-ase) and filter paper (FP)-cellulase was favoured by controlling the pH of the culture medium during fermentation at 5.0 . Sodium citrate (0.5%), sodium phytate (0.1%), Tween-80 (0.2%, v/v) and asparagine (0.07%) had stimulating effects on the productivity of cellobiase, CMC-ase and FP-cellulase . Potassium dihydrogen phosphate doubled the yield of CMC-ase but had a slight effect on FP-cellulase and cellobiase . Wheat bran had a pronounced stimulating effect on the production of cellobiase and CMC-ase . The combined effects of these stimulators resulted in an enzyme preparation rich in cellobiase and contained 18.5, 0.29 and 2.21 U/ml of cellobiase, FP-cellulase and CMC-ase, respectively . A high cellobiase/FP-cellulase ratio of 63.8:1 was thus obtained with the fungal enzyme preparation . The cellobiase activity was maximal at pH 5.0 and showed good thermostability.

Caries Res, 1995, 29(6), 470 - 6
An investigation into the ability of soft drinks to adhere to enamel; Ireland AJ et al.; Loss of enamel due to dietary causes, either by acid erosion or the fermentation of dietary sugars, is well known . These processes will be affected by a number of factors, one of which is the ability of the food to adhere to the enamel . The aim of this study was to determine the thermodynamic work of adhesion of a number of soft drinks to enamel . The results indicated significant differences in the ability of various drinks to adhere to enamel in vivo . In addition to obtaining a ranking of the drinks under test, the likelihood of them being displaced by saliva was considered.

Rocz Panstw Zakl Hig, 1995, 46(3), 243 - 6
{Level of histamine and tyramine in ripening cheeses}; Fonberg-Broczek M et al.; Histamine poisoning is a foodborne chemical intoxication resulting from the ingestion of food products containing high levels of histamine . Historically, histamine poisoning has been attributed to the consumption of fish species belonging to the Scomberesocidae and Scombridae families and other sea fish, but histamine poisoning outbreaks may occur after the consumption of cheese, or other types of fermented foods . Also tyramine has been proved as a cause of adverse reactions, involving headache, hypertensive crisis and interactions with antidepressive drugs, which were observed after consumption of ripening cheeses . The formation of high levels of histamine and tyramine in foods is directly correlated to the level of microorganisms, possessing the enzymes: histidine and tyrozyne decarboxylases, and also with the concentration of histidine and tyrosine free substrate . Proteolysis, which takes place during ripening of cheeses may play role in the release of free histidine and tyrosine . This study reports on the levels of histamine and tyramine in ripening cheeses taken from Polish food market . 43 samples of soft and hard cheeses were investigated . Histamine was measured according to the AOAC fluorometric method . Tyramine was measured after column separation and purification, according to the spectrofluorometric technique with 1-nitroso-2-ortophtalate aldehyde, according to Carou with couple of modifications by authors . Histamine levels ranged from 0 to 157 mg/kg and tyramine levels ranged from 3.8 to 575 mg/kg . The very high levels of histamine and tyramine in many samples of cheeses support the opinion, that sometimes the storage temperature has not been sufficient to stop bacterial multiplication and in consequence enzymatic activity of decarboxylases of native amino acids--precursors of biogenic amines in ripening cheeses.

Genetica, 1995, 96(3), 257 - 68
Enzyme polymorphism in Drosophila melanogaster populations collected in two different habitats in Hungary; Pecsenye K et al.; The level of enzyme polymorphism was compared in ten Drosophila melanogaster populations collected in farmyards and distilleries in two regions of Hungary . The total genetic diversity was partitioned into between- and within-population components at each investigated locus using Wright's F-statistics . Population differentiation was studied in two different ways . Genetic distances between pairs of populations were calculated and a hierarchical analysis of gene diversity was performed . Based on the F values gene flow was estimated among the populations at different levels of the hierarchy . The results indicated that our 'farmyard populations' collected within a region could be considered as parallel samples from a panmictic population rather than samples of distinct populations . In distilleries, the flies might be influenced by two different evolutionary forces: (i) selection due to the extremely high concentration of ethanol in the fermenting mash and (ii) genetic drift due to the combination of repeated founder effects and fluctuating population size . Our results suggested that 'distillery populations' could not be regarded as real populations either . They could be considered as peculiar cases: founder individuals taken from the total population (region) established special populations which survived in the distilleries for many generations . Thus the dominating force acting on the 'distillery populations' was genetic drift.

J Antibiot (Tokyo), 1995 Jan, 48(1), 53 - 8
Fudecalone, a new anticoccidial agent produced by Penicillium sp . FO-2030; Tabata N et al.; Penicillium sp . FO-2030, a soil isolate, was found to produce a new anticoccidial compound . The active compound, designated fudecalone, was isolated from the fermentation broth of the producing strain by solvent extraction, silica gel column chromatography and preparative HPLC . The structure of fudecalone was elucidated to be 3,3a,6,6a,7,8,9,10-octahydro-1-hydroxy-4,7,7-trimethyl-1H-naphtho{1,8a- c}furan-6-one mainly by spectroscopic studies including various NMR measurements . The anticoccidial activity using cell systems indicated that schizont formation of monensin-resistant Eimeria tenella was completely inhibited by fudecalone at concentrations more than 16 microM.

FEMS Microbiol Lett, 1995 Jan 1, 125(1), 77 - 82
Isolation and characterization of a new hydrogen-utilizing bacterium from the rumen; Rieu-Lesme F et al.; A new H2/CO2-utilizing acetogenic bacterium was isolated from the rumen of a mature deer . This is the first report of a spore-forming Gram-negative bacterial species from the rumen . The organism was a strictly anaerobic, motile rod and was able to grow autotrophically on hydrogen and carbon dioxide . Acetate was the major product detected . Glucose, fructose and lactate were also fermented heterotrophically . The optimum pH for growth was 7.0-7.5, and the optimum temperature was 37-42 degrees C . Yeast extract was required for growth and rumen fluid was highly stimulatory . The DNA base ratio was 52.9 +/- 0.5 mol% G+C . On the basis of these characteristics and fermentation products, the isolate was considered to be different from acetogenic bacteria described previously.

Br J Nutr, 1995 Jan, 73(1), 111 - 23
Digestion of raw banana starch in the small intestine of healthy humans: structural features of resistant starch; Faisant N et al.; The digestion of freeze-dried green banana flour in the upper gut was studied by an intubation technique in six healthy subjects over a 14 h period . Of alpha-glucans ingested, 83.7% reached the terminal ileum but were almost totally fermented in the colon . Structural study of the resistant fraction showed that a small part of the alpha-glucans which escaped digestion in the small intestine was composed of oligosaccharides from starch hydrolysis, whereas the rest was insoluble starch in granule form with physical characteristics similar to those of raw banana starch . Passage through the small intestine altered granule structure by increasing susceptibility to further alpha-amylase hydrolysis . Compared with resistant starch values in vivo, those obtained with the in vitro methods tested were inadequate to estimate the whole fraction of starch reaching the terminal ileum.

Int J Syst Bacteriol, 1995 Jan, 45(1), 29 - 31
Mycoplasma adleri sp . nov., an isolate from a goat; Del Giudice RA et al.; Mycoplasma sp . strain G145T (T = type strain) was isolated from a goat's abscessed ankle . Strain G145T required cholesterol or serum for growth and possessed characteristics similar to those of other members of the genus Mycoplasma . This strain was serologically distinct from previously described Mycoplasma species and from a group of currently unnamed strains thought to belong to the genus Mycoplasma . Strain G145T hydrolyzed arginine, but did not hydrolyze urea or ferment glucose . The guanine-plus-cytosine content of the DNA was 29.6 mol% . We propose that strain G145 (= ATCC 27948) is the type strain of a new species, for which we propose the name Mycoplasma adleri.

Am J Clin Nutr, 1995 Jan, 61(1), 135 - 40
Mycoprotein reduces glycemia and insulinemia when taken with an oral-glucose-tolerance test; Turnbull WH et al.; This study investigated the effects of mycoprotein, a food produced by the continuous fermentation of Fusarium graminearum (Schwabe), on acute glycemia and insulinemia in normal healthy individuals . Subjects participated in two single-meal study periods in a crossover design . After an overnight fast, subjects were given milkshakes containing mycoprotein or a control substance, which were isoenergetic and nutrient balanced . Each milkshake contained 75 g carbohydrate, equivalent to a standard World Health Organization oral-glucose-tolerance test . Blood samples were taken fasting and at 30, 60, 90, and 120 min postprandially for the measurement of serum glucose and insulin . Glycemia was reduced postmeal after mycoprotein compared with the control and was statistically significant at 60 min (13% reduction) . Insulinemia was reduced postmeal after mycoprotein compared with the control and was statistically significant at 30 min (19% reduction) and 60 min (36% reduction) postmeal . These results may be significant in the dietary treatment of diabetes.

Curr Genet, 1995 Jan, 27(2), 110 - 22
Control of glucose influx into glycolysis and pleiotropic effects studied in different isogenic sets of Saccharomyces cerevisiae mutants in trehalose biosynthesis; Neves MJ et al.; The GGS1/TPS1 gene of the yeast Saccharomyces cerevisiae encodes the trehalose-6-phosphate synthase subunit of the trehalose synthase complex . Mutants defective in GGS1/TPS1 have been isolated repeatedly and they showed variable pleiotropic phenotypes, in particular with respect to trehalose content, ability to grow on fermentable sugars, glucose-induced signaling and sporulation capacity . We have introduced the fdp1, cif1, byp1 and glc6 alleles and the ggs1/tps1 deletion into three different wild-type strains, M5, SP1 and W303-1A . This set of strains will aid further studies on the molecular basis of the complex pleiotropic phenotypes of ggs1/tps1 mutants . The phenotypes conferred by specific alleles were clearly dependent on the genetic background and also differed for some of the alleles . Our results show that the lethality caused by single gene deletion in one genetic background can become undetectable in another background . The sporulation defect of ggs1/tps1 diploids was neither due to a deficiency in G1 arrest, nor to the inability to accumulate trehalose . Ggs1/tps1 delta mutants were very sensitive to glucose and fructose, even in the presence of a 100-fold higher galactose concentration . Fifty-percent inhibition occurred at concentrations similar to the Km values of glucose and fructose transport . The inhibitory effect of glucose in the presence of a large excess of galactose argues against an overactive glycolytic flux as the cause of the growth defect . Deletion of genes of the glucose carrier family shifted the 50% growth inhibition to higher sugar concentrations . This finding allows for a novel approach to estimate the relevance of the many putative glucose carrier genes in S . cerevisiae . We also show that the GGS1/TPS1 gene product is not only required for the transition from respirative to fermentative metabolism but continuously during logarithmic growth on glucose, in spite of the absence of trehalose under such conditions.

Wien Med Wochenschr, 1995, 145(6), 143 - 7
{A case of patient homicide}; Beine KH; The phenomenon of patient homicides committed by health service employees has, in the previous years, repeatedly aroused much attention . The cases made known in Germany, the USA, Holland, Norway, and Austria appear to provide evidence to the effect that we are not only dealing with unique incidents . The scientific investigation of this especially sensitive taboo-topic is, to date, missing . The judicial trials carried out emphatically indicate that culprit motives, colleague behavior, but also to a large extent decisions made by superiors remain unclear . It remains controversial, what effect working conditions, strain of employees, their level of education and personal viewpoints over such criminal acts they possess . Finally, the long latency period between the first internal suspicions and the responsible parties' appropriate reactions requires duplicatable explanation . The following paper presents a German single-case study of patient homicide by a female nurse . The focus on causality rests on the presentation of developments up to the point where the long-fermenting suspicion could no longer be dismissed, and appropriate consequences took place . The account largely avoids the "definite" findings required during the judicial process . It concerns rather above all an open, uncertain, and possibly without external influence course of development which in stages each colleague in the health professions can trace, to the point where the uncertain and horrifying suspicion became a certainty . With this single-case study in hand it is made understandable in which ways personal circumstances and professional conditions at the worksituation can intertwine in such a way that the original motivation to help turns into its abysmal opposite . It is the author's intention to make preventive learning possible through this single case study . Every employee in the health professions should proceed on the assumption that such occurrences could also in his own field of work come to pass . In this respect, it is of considerable importance to differentiate between hasty and untenable incriminations and original increasing early-warning signs.

Rev Latinoam Microbiol, 1995 Jan-Mar, 37(1), 19 - 26
{Gardnerella vaginalis biotypes: modification of a proposed system}; Pedraza-Aviles AG et al.; A modified scheme is proposed for biotyping Gardnerella vaginalis based on detection of hippurate hydrolysis, beta-galactosidase (ONPG) and lipase, and fermentation of arabinose, galactose and xylose . Thirty three biotypes were found among 140 strains from women with and without bacterial vaginosis (non-specific vaginitis) . The distribution of biotypes were found to be significantly different, being more predominant the biotypes 1A; 5G; 7A; 7D and 7G in women with vaginosis and the biotypes 5G and 6H in women without vaginosis . These data suggest that some biotypes of Gardnerella vaginalis are associated with bacterial vaginosis.

Nahrung, 1995, 39(2), 132 - 8
Effect of processing on the composition of dietary fibre and starch in some legumes; Veena A et al.; The effect of processing on the total dietary fibre (TDF) insoluble (IDF) and water-soluble (SDF) fractions as well as total (TS), available (AS) and resistant (RS) starch were studied in three legumes, viz . bengalgram (Cicer arietinum L.), Cowpea (Vigna unguiculata) and greengram (Vigna radiata) . The processes studied were fermentation, germination, pressure-cooking and roasting . The dietary fibre (DF) content and its components were determined using the enzymatic-gravimetric method . The TS content was determined by the enzymatic method after solubilization with KOH . The DF content ranged from 23.2 to 25.6 g/100 g in the raw and 16.0 to 31.5 g/100 g in the processed legumes . All the processing treatments significantly decreased the SDF content and increased the IDF content of all the three legumes . The mean TS, AS and RS content of the raw legumes were similar, 46.9, 36.7 and 10.2 g/100 g respectively . AS content of all the legumes was reduced by the processing treatments, except pressure cooking . Correspondingly, higher amounts of RS were observed in the processed legumes, except pressure cooked, resulting in an increase in the TDF content.

J Basic Microbiol, 1995, 35(2), 117 - 21
Simultaneous raw starch hydrolysis and ethanol fermentation by glucoamylase from Rhizoctonia solani and Saccharomyces cerevisiae; Singh D et al.; Crude glucoamylase preparation from Rhizoctonia solani was used to saccharify raw and cooked starch . Various concentrations of potato starch and wheat flour from 10-40%, w/v were used for mashing but 30% was found to be the optimal and economical . The saccharified mash yielded 5.89%, v/v ethanol in a simultaneous saccharification and fermentation process using a yeast strain Saccharomyces cerevisiae (SC-39) at 35 degrees C for 4 days . Removal of inhibitory substances from the fermenting broth through dialysis caused considerable increase in ethanol production.

Antonie Van Leeuwenhoek, 1995, 67(3), 261 - 79
Physiological and technological aspects of large-scale heterologous-protein production with yeasts; Hensing MC et al.; Commercial production of heterologous proteins by yeasts has gained considerable interest . Expression systems have been developed for Saccharomyces cerevisiae and a number of other yeasts . Generally, much attention is paid to the molecular aspects of heterologous-gene expression . The success of this approach is indicated by the high expression levels that have been obtained in shake-flask cultures . For large-scale production however, possibilities and restrictions related to host-strain physiology and fermentation technology also have to be considered . In this review, these physiological and technological aspects have been evaluated with the aid of numerical simulations . Factors that affect the choice of a carbon substrate for large-scale production involve price, purity and solubility . Since oxygen demand and heat production (which are closely linked) limit the attainable growth rate in large-scale processes, the biomass yield on oxygen is also a key parameter . Large-scale processes impose restrictions on the expression system . Many promoter systems that work well in small-scale systems cannot be implemented in industrial environments . Furthermore, large-scale fed-batch fermentations involve a substantial number of generations . Therefore, even low expression-cassette instability has a profound effect on the overall productivity of the system . Multicopy-integration systems may provide highly stable expression systems for industrial processes . Large-scale fed-batch processes are typically performed at a low growth rate . Therefore, effects of a low growth rate on the physiology and product formation rates of yeasts are of key importance . Due to the low growth rates in the industrial process, a substantial part of the substrate carbon is expended to meet maintenance-energy requirements . Factors that reduce maintenance-energy requirements will therefore have a positive effect on product yield . The relationship between specific growth rate and specific product formation rate (kg product.{kg biomass}-1.h-1) is the main factor influencing production levels in large-scale production processes . Expression systems characterized by a high specific rate of product formation at low specific growth rates are highly favourable for large-scale heterologous-protein production.

Antonie Van Leeuwenhoek, 1995, 67(3), 243 - 53
Effects of growth conditions on mitochondrial morphology in Saccharomyces cerevisiae; Visser W et al.; Effects of growth conditions on mitochondrial morphology were studied in living Saccharomyces cerevisiae cells by vital staining with the fluorescent dye dimethyl-aminostyryl-methylpyridinium iodine (DASPMI), fluorescence microscopy, and confocal-scanning laser microscopy . Cells from respiratory, ethanol-grown batch cultures contained a large number of small mitochondria . Conversely, cells from glucose-grown batch cultures, in which metabolism was respiro-fermentative, contained small numbers of large, branched mitochondria . These changes did not significantly affect the fraction of the cellular volume occupied by the mitochondria . Similar differences in mitochondrial morphology were observed in glucose-limited chemostat cultures . In aerobic chemostat cultures, glucose metabolism was strictly respiratory and cells contained a large number of small mitochondria . Anaerobic, fermentative chemostat cultivation resulted in the large, branched mitochondrial structures also seen in glucose-grown batch cultures . Upon aeration of a previously anaerobic chemostat culture, the maximum respiratory capacity increased from 10 to 70 mumole.min-1.g dry weight-1 within 10 h . This transition resulted in drastic changes of mitochondrial number, morphology and, consequently, mitochondrial surface area . These changes continued for several hours after the respiratory capacity had reached its maximum . Cyanide-insensitive oxygen consumption contributed ca . 50% of the total respiratory capacity in anaerobic cultures, but was virtually absent in aerobic cultures . The response of aerobic cultures to oxygen deprivation was qualitatively the reverse of the response of anaerobic cultures to aeration . The results indicate that mitochondrial morphology in S . cerevisiae is closely linked to the metabolic activity of this yeast: conditions that result in repression of respiratory enzymes generally lead to the mitochondrial morphology observed in anaerobically grown, fermenting cells.

J Ind Microbiol, 1995 Jan, 14(1), 52 - 7
Clarification of animal cell cultures on a large scale by continuous centrifugation; Kempken R et al.; Animal cells from 80-L and 2000-L fed batch fermentations were removed by a prototype disc stack centrifuge in order to achieve a fast and reliable separation of solids from large quantities of cell culture fluids . The clarification capacity was excellent for animal cells but particles remained in the liquid phase and affected further downstream processing of the cell-free harvest fluid . No significant loss of product was observed . A number of parameters were monitored to optimize process conditions for use with animal cells.

Biotechnol Prog, 1995 Jan-Feb, 11(1), 64 - 70
The use of dielectric permittivity for the control of the biomass level during biotransformations of toxic substrates in continuous culture; Markx GH et al.; Since the permittivity signal of a cell suspension measured using dielectric spectroscopy at radio frequencies is essentially determined only by viable (intact) cells, it can be used to monitor the concentration of viable cells in a fermentor in which a large proportion of the cells is nonviable . This could be used to select for organisms that are highly resistant to stress, for example from toxic chemicals used in biotransformations . We sought to control the concentration of viable yeast cells in a fermentor by adding small amounts of benzaldehyde, thus imposing a selection regime for cells highly resistant to benzaldehyde . However, after the addition of benzaldehyde, an increase in the permittivity is seen first followed by a decrease, thus making the control of biomass using a standard on-off controller difficult . It is shown that it is possible effectively to control the level of viable biomass in the fermentor in the presence of a large concentration of necromass using a combination of an inverse response compensator and a PID controller.

Biosci Biotechnol Biochem, 1995 Jan, 59(1), 150 - 1
Measurement of Gly m Bd 30K, a major soybean allergen, in soybean products by a sandwich enzyme-linked immunosorbent assay; Tsuji H et al.; By a sandwich enzyme-linked immunosorbent assay, a soybean major allergen, Gly m Bd 30K, in soybean products was measured . The allergen occurred at high concentrations in soy milk, tofu, kori-dofu, and yuba, but its content in kinako was small . No allergen was found in fermented foods such as miso, shoyu, and natto . The allergen was clearly shown to occur in meat balls, beef croquettes, and fried chicken that contained soybean protein isolate.

Lett Appl Microbiol, 1995 Jan, 20(1), 61 - 4
Interactions between rumen anaerobic fungi and ciliate protozoa in the degradation of rice straw cell walls; Widyastuti Y et al.; Suspensions of mixed rumen protozoa were added to incubations of the anaerobic fungus Neocallimastix patriciarum with rice straw cell walls . The protozoa did not influence the dry matter lost from the straw, or the solubilization of monosaccharides, but they had a marked effect on the fermentation products formed . Studies with 14C-labelled protozoa suggested that the presence of protozoa reduced the fungal carboxymethylcellulase activity to around half of that found in pure cultures of the fungus.

Bioprocess Technol, 1995, 20, 135 - 85
Cell aggregation and sedimentation; Davis RH; The aggregation of cells into clumps or flocs has been exploited for decades in such applications as biological wastewater treatment, beer brewing, antibiotic fermentation, and enhanced sedimentation to aid in cell recovery or retention . More recent research has included the use of cell aggregation and sedimentation to selectively separate subpopulations of cells . Potential biotechnological applications include overcoming contamination, maintaining plasmid-bearing cells in continuous fermentors, and selectively removing nonviable hybridoma cells from perfusion cultures.

Yeast, 1995 Jan, 11(1), 1 - 14
2-micron vectors containing the Saccharomyces cerevisiae metallothionein gene as a selectable marker: excellent stability in complex media, and high-level expression of a recombinant protein from a CUP1-promoter-controlled expression cassette in cis; Hottiger T et al.; We have constructed 2-micron-based yeast expression vectors containing a copy of the metallothionein (CUP1) gene of Saccharomyces cerevisiae as a semi-dominant, selectable marker . When used for the expression of the thrombin inhibitor hirudin, originally derived from the leech Hirudo medicinalis, these vectors displayed the following characteristics . (1) In the presence of copper salts, they were mitotically more stable than similarly designed control vectors lacking the CUP1 gene . In copper-sensitive host strains, the apparent plasmid stability was 100%, even in complex media and during fed-batch fermentation for an extended period of time . (2) Use of the CUP1-stabilized plasmids improved the production of hirudin by both copper-sensitive and copper-resistant hosts . The highest hirudin titers were obtained with a delta CUP1 host . (3) Copper selection resulted in a moderate increase in average plasmid copy numbers (up to two-fold) as assessed by measuring hirudin expression from a constitutive promoter (GAPFL) . This effect was most noticeable if the vector showed an asymmetric segregation pattern (i.e., high rates of plasmid loss in the absence of copper) . (4) The CUP1 marker proved particularly useful in combination with a CUP1-promoter-controlled expression cassette on the same plasmid . In such a set-up, the rates of transcription of the heterologous protein and that of the selectable marker are tightly linked . Therefore, an increase in selective pressure directly provokes an increase in product yields . In a copper-sensitive host strain, this plasmid design allowed for the production of very high amounts of biologically active hirudin . Our results clearly establish the utility of the CUP1 marker in the construction of stable yeast expression vectors.

Food Addit Contam, 1995 Jan-Feb, 12(1), 31 - 40
Fermentation of wort containing added ochratoxin A and fumonisins B1 and B2; Scott PM et al.; Ochratoxin A (OA), fumonisin B1 (FB1) and fumonisin B2 (FB2) were added to wort at levels of 0.19, 0.95 and 0.95 micrograms/ml, respectively, and fermented for up to 8 days by three strains of Saccharomyces cerevisiae . Decreases of OA in the beer over this period were estimated from straight line slopes to be 2-13% . Losses of FB1 and FB2 were estimated to be 3-28% and 9-17% respectively . Some OA was taken up by the yeast, up to 21% in a detailed study with one strain . In contrast, uptake of fumonisins by yeast was negligible (< 1% FB1 and < 2% FB2) . In control experiments, OA, FB1 and FB2 were found to be stable when added to yeast-free wort and kept for up to 8 days at 25 degrees C . In addition, spiking experiments with blank day 0-8 fermenting wort samples showed method recoveries averaging 87-91% . None of the mycotoxins was detected in control fermentations where they were not added to the wort.

Nutrition, 1995 Jan-Feb, 11(1), 37 - 45
Digestive processes in the human colon; Nordgaard I et al.; The presence or absence of a normal small bowel is evidently important for the digestion and absorption of nutrients in humans . The importance, however, of the large intestine as an organ with digestive potential and an ability to salvage energy is much less appreciated . Whereas the bacterial fermentation of plant polysaccharides, with the production and absorption of short-chain fatty acids (SCFAs), contributes 60-90% of all the energy requirements in plant-eating animals, the colonic fermentation in humans is of minor importance for nutrition, with only 5-10% of the energy requirements available from colonic digestion of starch, nonstarch polysaccharides, and protein not absorbed in the small bowel, if the intestine has a normal length and function . In contrast, the digestive resource of the large bowel might be important for people with reduced upper-gut function and with the malabsorption of large amounts of dietary nutrients to the cecum, e.g., in patients with short bowel . The substrates available for bacterial fermentation and for the maintenance of the colonic flora are largely starch and nonstarch polysaccharides (dietary fiber) . Whereas nonstarch polysaccharides are undegradable by amylase in the small intestine, starch is hydrolyzed by amylase, but with very different rates and to very different degrees dependent on the origin and structure of the starches . The unequal susceptibility to amylase explains the different amount of starch that is not absorbed in the small intestine . The rate of colonic fermentation of starch has also been shown to relate to the rate of starch hydrolysis by amylase.(ABSTRACT TRUNCATED AT 250 WORDS)

Antonie Van Leeuwenhoek, 1995, 67(1), 79 - 89
Source separation, selective collection and in reactor digestion of biowaste; Gellens V et al.; Biowaste or the organic fraction of domestic waste, for instance kitchen, fruit and garden waste, is collected selectively in several European communities . The complementary fraction is called the dry or non recyclable fraction . A Dutch study reported that 92% of the participants that have a weekly collection service of both fractions (biowaste and non recyclable fraction) and 80% of the participants in the alternating collection program (one week biowaste and the next week non recyclable fraction) are pleased with separate collection of biowaste . Dominating problems that arise in case of alternating collection are a repulsive odor and an infestation with flies and maggots . By expanding the definition of biowaste to include non recyclable or soiled paper like dirty newspapers, table napkins and paper handkerchiefs, most of these problems can be overcome without changing the way compostable waste is collected and processed . The expanded definition of biowaste was used in this paper . Over a 12 month period a quality survey of the collected biowaste was conducted by the composting facility Intercompost, Hoeselt, Belgium . A special aspect was the fact that in one participating community baby diapers were included in the soiled paper fraction; this is called "biowaste+" . The biowaste+ had a 10% non recyclable paper fraction opposed to only 1-2% of non recyclable paper present in the conventional biowaste . Baby diapers were a rather notable part (more than 80%) of this non recyclable paper fraction of biowaste+ and as a consequence might contribute to a large extent to improve the collection and treatment of biowaste . It was demonstrated that rural districts yielded about 35% more biowaste than more urban districts; resp . +/- 122 kg biowaste/capita . year versus +/- 90 kg biowaste/capita . year . In Hoeselt the biowaste+ yield was about 130 kg/capita.year . Biowaste+ is also separately collected in another Belgium community, namely Brecht . The purity level of the biowaste+ and the amount of non recyclable paper (including diapers) were comparable with the results of Hoeselt . In Hoeselt the biowaste+ fraction is composted aerobically . In Brecht on the other hand, the biowaste+ is processed using the Dry Anaerobic Composting process (DRANCO) . The latter process is discussed in more detail . The biological start-up of the dry anaerobic composting installation at Brecht, Belgium, is reported . The reactor has a total volume of 808 m3 and a design capacity of 730 m3 . After 2 months of start up, the fermentor was at full loading rate, i.e . 8 kg bVS/m3 reactor.day and the installation was working at full capacity, i.e . 40 ton/day.(ABSTRACT TRUNCATED AT 400 WORDS)

Antonie Van Leeuwenhoek, 1995, 67(1), 125 - 30
Acceleration of mass transfer in methane-producing loop reactors; Van den Heuvel JC et al.; Gas bubbles entrapped in methanogenic granules subjected to hydrostatic pressure oscillations during recirculation in loop reactors will induce intraparticle liquid flows, and thereby enhance mass transfer in excess of diffusion . This 'breathing particle' concept was clearly demonstrated in a well defined inorganic model system . The experimental results could be described satisfactory with a structured mathematical model, while a 30% improvement is predicted for methanogenic loop reactors as compared to constant pressure systems . It is concluded that acceleration of mass transfer in gas-producing systems offers challenging perspectives for both heterogeneous catalysis and biological fermentations.

Crit Rev Biotechnol, 1995, 15(1), 1 - 11
Tequila production; Cedeno M; Tequila is obtained from the distillation of fermented juice of agave plant, Agave tequilana, to which up to 49% (w/v) of an adjunct sugar, mainly from cane or corn, could be added . Agave plants require from 8 to 12 years to mature and during all this time cleaning, pest control, and slacken of land are required to produce an initial raw material with the appropriate chemical composition for tequila production . Production process comprises four steps: cooking to hydrolyze inulin into fructose, milling to extract the sugars, fermentation with a strain of Saccharomyces cerevisiae to convert the sugars into ethanol and organoleptic compounds, and, finally, a two-step distillation process . Maturation, if needed, is carried out in white oak barrels to obtain rested or aged tequila in 2 or 12 months, respectively.

Am J Hypertens, 1995 Jan, 8(1), 74 - 9
Effect of green tea rich in gamma-aminobutyric acid on blood pressure of Dahl salt-sensitive rats; Abe Y et al.; gamma-Aminobutyric acid (GABA) is known to be involved in the regulation of blood pressure by modulating the neurotransmitter release in the central and peripheral sympathetic nervous systems . This study investigated the antihypertensive effect of green tea rich in GABA (GABA-rich tea) in young and old Dahl salt-sensitive (S) rats . GABA-rich tea was made by fermenting fresh green tea leaves under nitrogen gas . In experiment 1, 21 11-month-old rats, fed a 4% NaCl diet for 3 weeks, were given water (group W), an ordinary tea solution (group T), or a GABA-rich tea solution (group G) for 4 weeks . The average GABA intake was 4.0 mg/rat per day . After 4 weeks of the treatment, blood pressure was significantly decreased in group G (176 +/- 4; P < .01) compared with group W (207 +/- 9) or group T (193 +/- 5 mm Hg) . Plasma GABA levels were more elevated in group G (111 +/- 54) than in group W (not detectable) or group T (14 +/- 8 ng/mL; P < .01 v G) . In experiment 2, 21 5-week-old rats, fed a 4% NaCl diet, were divided into groups W, T, and G . The average GABA intake was 1.8 mg/rat per day . Body weight or chow and beverage consumption did not differ significantly among the three groups . After 4 weeks of the treatment, although blood pressure was comparable in groups W and T (165 +/- 3 v 164 +/- 5 mm Hg, mean +/- SE), it was significantly lower in group G (142 +/- 3 mm Hg) than in the other groups (P < .01).(ABSTRACT TRUNCATED AT 250 WORDS)

Schweiz Monatsschr Zahnmed, 1995, 105(3), 306 - 10
{Cariogenic carbohydrates in maltodextrin-containing breast milk food substitutes}; Koch H et al.; Ten infant formulas containing maltodextrin were analysed for fermentable carbohydrates using enzymatic analysis test-combinations and a spectrophotometer . Besides lactose, sucrose and fructose an assessment was made of sugars typically contained in maltodextrin and corn syrup, namely maltose, maltotriose and glucose . Total carbohydrate was up to 10.3 g in 100 ml standard sample . Cariogenic sugars were found in concentrations between 4.0 and 7.3 g/100 ml . Declaration of the different types of carbohydrates, especially of maltodextrin/corn syrup proved to be insufficient in some products and consequently the consumer is not able to understand their cariogenic potential.

Peptides, 1995, 16(1), 151 - 64
Bioactive cyclic dipeptides; Prasad C; Cyclic dipeptides are among the simplest peptide derivatives commonly found in nature . Most cyclic dipeptides found to date appear to have emerged as by-products of fermentation and food processing . However, many are endogenous to members of animal and plant kingdoms; these include cyclo(Pro-Leu), cyclo(Pro-Val), cyclo(Pro-Phe), cyclo(Ala-Leu), cyclo(Pro-Tyr), cyclo(Pro-Trp), and cyclo(His-Pro) . Although the five cyclic dipeptides--cyclo(His-Pro), cyclo(Leu-Gly), cyclo(Tyr-Arg), cyclo(Asp-Pro), and cyclo(Pro-Phe)--exhibit interesting physiological and/or pharmacological activities in mammals, only one of these, cyclo(His-Pro), has been conclusively shown to be endogenous to mammals . On the other hand, cyclo(Leu-Gly), cyclo(Tyr-Arg), and cyclo(Asp-Pro) are structurally related to endogenous peptides Pro-Leu-Gly-NH2 (melanocyte-stimulating hormone release inhibiting factor), Tyr-Arg (kyotorphin), and Val-Pro-Asp-Pro-Arg (enterostatin), respectively, which may serve as precursor peptides . It needs to be determined, however, whether these peptides can indeed result from the processing of their respective precursors . In conclusion, it appears that cyclic dipeptides are a relatively unexplored class of bioactive peptides that may hold great promise for the future.

Support Care Cancer, 1995 Jan, 3(1), 81 - 3
Effects of active addition of bacterial cultures in fermented milk to patients with chronic bowel discomfort following irradiation; Henriksson R et al.; Radiotherapy is a cornerstone in the treatment of malignancies in the pelvis . Consequently, there is usually exposure of the intestine and especially the lower colon and rectum, with ensuing disturbances in bowel habits at different times following radiotherapy . The main problem is diarrhoea associated with lactose intolerance, bile salt absorption and fat malabsorption . Bacterial contamination has also been described . In the present study we have evaluated the influence of the active administration of specific bacterial cultures in fermented milk, which inhibit the growth of potentially pathogenic micro-organisms, to 40 consecutive patients with chronic alteration in their bowel habits caused by previous radiotherapy of pelvic malignancies . The results suggest that intake of fermented milk products could be of value in decreasing chronic bowel discomfort following radiotherapy of pelvic malignancies . However, a more extensive study is warranted in order to very the significance of the results and to find the optimal product.

Eur J Pediatr, 1995, 154(7 Suppl 2), S87 - 92
Hidden sources of galactose in the environment; Acosta PB et al.; A galactose-restricted diet free of lactose is lifesaving in patients with galactose-1-phosphate uridyl transferase (GALT) deficiency, but does not prevent long-term complications such as developmental delay, abnormal speech, poor growth and, in females, ovarian failure . Lactose, found in dairy products and as an extender in drugs, has been considered the primary source of galactose in the diet . Two recent publications reported that small amounts of galactose are present in many fruits and vegetables . We report the presence of considerable amounts of free galactose in some legumes (dried beans and peas) and the presence of bound galactose in many food plants . Galactose, in various glycosidic linkages, such as alpha-1,6, beta-1,3 and beta-1,4, and as a component of lipids, is ubiquitous in animals and plants . The bioavailability of alpha-1,6 and beta-1,3 linked galactose in foods is unknown . However, alpha-galactosidases found in plant and animal tissues may release galactose in alpha-1,6 linkage, and from diagalactosyldiacylglycerol . Galactose in beta-1,4 linkage and as monogalactosyldiacylglycerol may be released by beta-galactosidases in animal and plant tissues . Foods fermented by microorganisms for preparation or preservation purposes may contain free galactose . The role of free and bound galactose in cereals, fruits, legumes, nuts, organ meats, seeds, and vegetables in the poor outcome seen in some patients with GALT deficiency is unknown . It is certain that no patients with GALT deficiency have ever ingested a galactose-free diet.

Arch Tierernahr, 1995, 47(3), 295 - 300
Effect of yeast supplementation on health, performance and rumen fermentation in beef bulls; Fiems LO et al.; The effect of 0, 6 or 60 g yeast (Saccharomyces cerevisiae) daily on health and performance was investigated in 90 double-muscled and 48 non-double-muscled Belgian White-blue bulls during 60 and 51 days, respectively, upon arrival at the experimental farm . The yeast was incorporated in the concentrate, which was fed at 2 kg d-1 during the first ten days and at 2.5 kg d-1 afterwards . Besides, maize silage was fed up to 8 kg d-1, while grass hay was offered ad libitum . Feed intake, growth rate and number of sick animals were not affected by the yeast addition . Morbid animals required a similar number of days with antibiotic therapy for each yeast level within each beef strain . Rumen samples taken from 6 non-double-muscled bulls in the last but one week showed a decreased concentration of volatile fatty acids when 6 g yeast was fed daily . Except butyric acid concentration, rumen fermentation parameters were not altered . Yeast supplementation during an adaptation period after purchase did not affect health status and growth performance.

Arch Tierernahr, 1995, 47(3), 271 - 86
{Simulation of nutrient dynamics in the rumen of sheep and cattle considering the feed composition, level of feed intake and feeding frequency . 2 . Model validation}; Grathwol J et al.; A mathematical model of rumen fermentation processes was validated with 65 sheep experiments and 45 cattle experiments, respectively . Further, it was shown how the model reacts when the feed composition, the level of feed intake and the feeding frequency was changed . The model predictions were satisfactory for the digestibility of organic matter and neutral detergent fibre (NDF) in rumen, the production of volatile fatty acids and the non-ammonia-N (NAN) flow to duodenum . The partition of NAN in microbial and feed N was estimated with lower reliability . The effects of variation of feeding level, feeding frequency and roughage quality (crude protein, lignin) on digestion processes have been simulated correctly . On the other hand, the effects of the proportion of roughage to concentrate have not been reproduced sufficiently with the mechanisms included in the model . To make correct predictions in this area too, it is necessary to integrate the rumen pH and its effects on rumen processes into the model . A mechanistic approach for estimation of the velocity constants for passage of substances out of the rumen would improve the model.

Arch Tierernahr, 1995, 47(3), 255 - 70
{Simulation of nutrient dynamics in the rumen of sheep and cattle considering the feed composition, level of feed intake and feeding frequency . 1 . Model description}; Grathwol J et al.; The aim of this work was to develop a dynamic, mechanistic computer-model, which can be used to simulate digestion, outflow and pools of different nutrients in the rumen of sheep and cattle and which reacts on changes of the feed composition, on the level and the frequency of feeding . The model consists of 35 flux- and 17 differential equations and works under cyclic steady-state conditions . The following mechanism are integrated into the model: The three substrates protein, neutral detergent fibre (NDF) and non-fibre-carbohydrates are degraded by three specific groups of microbes . A fourth group degrades NDF and non-fibre-carbohydrates following the principle of competitive inhibition . The fermentation in the rumen serves for supply of energy for growth and for the maintenance of microbes . The rates of degradation are calculated from the turnover-time of the specific substrate and the amount of microbes . Recycling of N occurs through recycling of the microbial protein and the ruminohepatic pathway . If concentration of ammonia in rumen fluid decreases below 50 mg/l then the growth of microbes declines.

Appl Biochem Biotechnol, 1995 Spring, 51-52, 449 - 61
Optimization for a recombinant E . coli fed-batch fermentation; Chen Q et al.; The operating strategy that produces the maximum foreign protein expression for a fed-batch process is desired . This is achieved by using a feasible quadratic programming (FSQP) algorithm with a structured model that describes cell growth and product formation for recombinant E . coli . Optimization calculations for a fed-batch culture have not been performed with a model of this complexity up to this point . A constraint on the maximum cell concentration was included . For a fixed value of batch time, the results show that the optimal time profile of feed flow rate can increase the yield of foreign protein by 12-29% over a constant feed rate policy . Also, it was found that the computation time for the FSQP algorithm can be reduced significantly by considering suboptimal profiles of the feed rate, with a minor effect on calculated protein yield.

Appl Biochem Biotechnol, 1995 Spring, 51-52, 423 - 35
Fermentation of sugars in orange peel hydrolysates to ethanol by recombinant Escherichia coli KO11; Grohmann K et al.; The conversion of monosaccharides in orange peel hydrolysates to ethanol by recombinant Escherichia coli KO11 has been investigated in pH-controlled batch fermentations at 32 and 37 degrees C . pH values and concentration of peel hydrolysate were varied to determine approximate optimal conditions and limitations of these fermentations . Very high yields of ethanol were achieved by this microorganism at reasonable ethanol concentrations (28-48 g/L) . The pH range between 5.8 and 6.2 appears to be optimal . The microorganism can convert all major monosaccharides in orange peel hydrolysates to ethanol and to smaller amounts of acetic and lactic acids . Acetic acid is coproduced in equimolar amounts with ethanol by catabolism of salts of galacturonic acid.

J Comp Physiol {B}, 1995, 165(3), 193 - 202
Digesta passage and functional anatomy of the digestive tract in the desert tortoise (Xerobates agassizii); Barboza PS; The herbivorous tortoise Xerobates agassizii contends with large fluctuations in the quality and abundance of desert pastures . Responses to grass (Schismus barbatus), herbage (Sphaeralcea ambigua) and pelleted diets were studied in captive animals . Digestive anatomy was investigated in wild tortoises . Cornified esophageal epithelia and numerous mucus glands along the digestive tract indicated a resistance to abrasive diets . Gastric contents were acidic whereas hindgut digesta were near neutral pH . The colon was the primary site of fermentation with short-chain fatty acids mainly comprised of acetate (69-84%), propionate (10-15%) and n-butyrate (1-12%) . Fibre digestion was extensive and equivalent to 22-64% of digestible energy intakes . Large particles of grass (25 mm; Cr-mordants) were excreted as a pulse but retained longer than either fluids (Co-EDTA) or fine particles (2 mm; Yb) . Patterns of marker excretion suggested irregular mixing of only the fluid and fine particulate digesta in the stomach and the colon . Mean retention times of Cr-mordants were 14.2-14.8 days on the grass and high-fibre pellets . Intakes of grass were low and accompanied by smaller estimates of digesta fill than for the high-fibre pellets . Digestive capacity was large and estimated at 11-21% of body mass on these diets . The capacious but simple digestive anatomy of the tortoise may provide the greatest flexibility in utilizing a variety of forages in its unreliable habitat.

JPEN J Parenter Enteral Nutr, 1995 Jan-Feb, 19(1), 63 - 8
Influence of three different fiber-supplemented enteral diets on bowel function and short-chain fatty acid production; Kapadia SA et al.; BACKGROUND: Dietary fiber is known to influence bowel habit and gastrointestinal mucosal cell morphology and function . large-bowel function is particularly influenced by insoluble, poorly fermentable fiber sources, whereas mucosal function is affected by fiber sources that are soluble and highly fermentable . The aim of the present study was to compare bowel function during consumption of a self-selected diet, a fiber-free enteral diet, and three polymeric enteral diets, each supplemented with a fiber with different fermentation characteristics . The fiber sources used were oat, soy oligosaccharide, and soy polysaccharide . METHODS: Seven healthy subjects consumed four diets in random order for 4 to 7 days . These were a self-selected diet, a 2-L polymeric enteral diet, and a 2-L polymeric enteral diet supplemented with 15 g of total dietary fiber per liter derived from either soy oligosaccharide fiber (75 g/L) or oat fiber (15 g/L) . An additional six healthy subjects were randomly assigned to three diets (4 to 7 days): a self-selected diet, a 2-L polymeric enteral diet, or the same 2-L polymeric enteral diet supplemented with 20 g of soy polysaccharide fiber per liter (15 g of total dietary fiber per liter) . Bowel function was assessed by measuring whole-gut transit time, mean daily stool wet weights, and bowel movement frequency per day . Fermentation characteristics of the different fiber sources were determined quantitatively and qualitatively by measuring short-chain fatty acids produced during in vitro stool culture . RESULTS: Total short-chain fatty acid and butyric acid production with soy oligosaccharide fiber were significantly higher compared with values observed for soy polysaccharide fiber (p < .003), oat fiber (p < .005), and self-selected (control) diet (p < .003) . Compared with the fiber-free diet, consumption of the soy polysaccharide, oat, and soy oligosaccharide-fiber-supplemented enteral diets did not significantly (p > .05) alter whole-gut transit time or stool wet weight . However, bowel frequency was significantly improved by consumption of the soy polysaccharide-fiber-supplemented diet but not the oat fiber or soy oligosaccharide-fiber-supplemented diets . CONCLUSION: Compared with a fiber-free polymeric enteral diet, the daily consumption of an enteral diet supplemented with 30 g of total dietary fiber per day derived from a poorly fermentable oat fiber, a highly fermentable soy oligosaccharide fiber, or a moderately fermentable soy polysaccharide fiber has little impact, if any, on bowel function.

Biomed Sci Instrum, 1995, 31, 251 - 6
Modeling and optimising dextrose fermentation using a fluorosensor; Sundaram S et al.; Dextrose has been fermented in a Tokyo Rikakikai Fermentor at 32 degree celsius using seven different concentrations of yeast as seeding . The progress of the reaction was followed by measuring the fluorescent signal due to NADH with a Dr . Ingold (Switzerland) fluorosensor which has an excitation wavelength of 360 nm and measurement wavelength of 450 nm . The optimum concentration for this fermentation reaction is 30 percent seeding . At this concentration the biomass growth rate and final biomass concentration are a maximum . The fluorescent voltage vs time data fitted a first order model with an error of less than one percent . Further work on optimising the temperature is in progress.

Rapid Commun Mass Spectrom, 1995, 9(8), 717 - 22
Contribution of mass spectrometry to the structural confirmation of components of the antibiotic GE2270 complex; Colombo L et al.; The GE2270 complex consists mainly of GE2270 A (MW 1289), a thiazolyl peptide antibiotic whose structure originates from the modification of a chain of 14 amino acids in a process which creates six thiazole rings and one pyridine . Together with the main component, a number of structurally related molecules are co-produced in small quantities by fermentation . A preparative high-performance liquid chromatrography method was developed to isolate GE2270 factors B1, B2, C1, C2a, C2b, D1, D2, E and T . Their structures, preliminarily determined by 1H-nuclear magnetic resonance spectroscopy in comparison with GE2270 A, were confirmed by low and high resolution fast-atom bombardment mass spectrometry and studies on the intact molecules and on their main hydrolysis products . Their molecular weights range from 1246 to 1306 Da . The structural differences between the factors lie in the extent of methylation and/or oxidation of thiazole rings (D and E) and asparagine, and in the aromatization of the oxazoline ring.

Crit Rev Food Sci Nutr, 1995 Jan, 35(3), 191 - 229
Huitlacoche (Ustilago maydis) as a food source--biology, composition, and production; Valverde ME et al.; Huitlacoche is the ethnic name applied to the young fruiting bodies (galls) of the fungus Ustilago maydis, which causes common smut of maize (Zea mays L) . Biologists and agronomists have historically used U . maydis as a model to study a wide array of genetic, physiological, ecological, and phytopathological phenomena . In Mexico and other Latin American countries, huitlacoche has been used traditionally as human food, being highly regarded as an interesting dish or condiment . The food potential of huitlacoche is described here in terms of its chemical composition, which includes carbohydrates, proteins, fats, vitamins, and minerals . In addition, essential amino acids (especially lysine) and fatty acids (linoleate) are present in huitlacoche in considerable levels, adding to its nutritional attributes . The feasibility of growing U . maydis in submerged agitated culture has yielded a variety of fermentation products, including essential amino acids, proteins, vitamins, and flavorings, among others . Recent interest in developing huitlacoche as a cash crop has come from increasing acceptance by the North American public, who prize it as a new delicacy . However, research efforts are still needed to determine the biological factors involved in the establishment of U . maydis as a pathogen on the maize plant . This review deals with the role of huitlacoche as a food source, implicating the biological components that will determine the development of technologies for large scale production.

Schweiz Monatsschr Zahnmed, 1995, 105(7), 907 - 12
{Cariogenic carbohydrates in maltodextrins, glucose syrups and maltodextrin-containing infant tea}; Koch H et al.; Five maltodextrins and five corn syrups each, seven instant teas containing maltodextrin and one tea produced on a protein-base were analysed for fermentable carbohydrates using enzymatic analyses test combinations and a spectrophotometer . Analysis of the maltodextrins and glucose syrups demonstrated the heterogenicity of this group of substances and also some incompleteness in the declaration of maltose, maltotriose and glucose, sugars typically contained in these products . In standard samples of the instant teas cariogenic sugars were found in concentrations up to 0.7% . As these sugars were not declared in any of the products, the consumer is not able to assess the cariogenic potential of the ingredient maltodextrin . The intake of products containing maltodextrins or corn syrups must lead to an uncontrolled sugar consumption.

Appl Biochem Biotechnol, 1995 Jan, 50(1), 71 - 8
Solid-state fermentation of agricultural wastes into food through Pleurotus cultivation; Jwanny EW et al.; The technical feasibility of using agricultural wastes (mango and date industry wastes) as a substrate for the cultivation of Pleurotus ostreatus NRRL-0366 is evaluated . When comparing the biological efficiency of mushroom production, the highest yield of fruiting bodies was obtained using a mixture of date waste and rice straw at a ratio (1:1) (11.96%), followed by a mixture 3:1 (11.16%) . The lowest one was the mixture 2:1 (9.19%) . Fungus Pleurotus ostreatus NRRL-0366 can also be cultivated on mango waste supplemented with rice straw at a different ratio . The best one was the 1:1 mixture (10.18%), whereas the lowest was a mixture 3:1 (6.4%) . Comparing the results obtained favored the use of date waste as a substrate for growing Pleurotus ostreatus NRRL-0366 . Spawn was cultured on three different substrates as follows: Date waste alone (I); 1:1 (by wt) date waste and rice straw (II); 1:1:1 date waste, rice straw, and corncobs (III) . Final dry weight and composition of the fruiting bodies are tabulated for the three sets of conditions . Date waste and rice straw mixture (II) is a good source of nonstarchy carbohydrate (67%) and protein (27.44%) containing amounts of essential amino acids, especially lysine and low RNA (3.81%) . Elemental analysis were studied in the fruit bodies of the three media.

Acta Vet Hung, 1995, 43(1), 179 - 90
Effect of hydrothermal treatment of rice straw on its composition and in sacco digestibility and in vitro fermentation by rumen microorganisms; Adya M et al.; Chemical composition, in sacco rumen disappearance of various cell wall constituents (CWC) and in vitro fermentation pattern of hydrothermally treated (1 to 14 kp/cm2 pressure for 5 min) rice straw was examined . At 10 kp/cm2 pressure treatment (maximum effect) the contents of dry matter (DM), organic matter (OM), neutral detergent fibre (NDF), acid detergent fibre (ADF), hemicellulose (HC) and cellulose (CE) were decreased by 32.5, 35.3, 27.8, 10.2, 61.2 and 25.1%, respectively (P < 0.05), over the untreated control . The in sacco rumen disappearance of DM, OM, HC and CE from rice straw treated at 8 kp/cm2 pressure (maximum effect) and incubated for 48 h was increased from 53.2 to 77.7, 52.4 to 80.3, 49.5 to 82.0 and 49.2 to 79.3%, respectively (P < 0.01) . In vitro production of total volatile fatty acids and the content of TCA-insoluble protein was also significantly higher (P < 0.05) on treated compared with untreated straw.

Caries Res, 1995, 29(3), 181 - 7
Effects of chlorhexidine-fluoride mouthrinses on viability, acidogenic potential, and glycolytic profile of established dental plaque; Giertsen E et al.; Inhibition of dental plaque acidogenicity by chlorhexidine (CHX) mouthrinses has been ascribed to a long-lasting bacteriostatic effect due to binding of CHX to oral surface structures combined with a slow release rate from the binding sites . The present aims were to study the effects of CHX-containing mouthrinses on the viability and glycolytic activity of established plaque in order to assess the bactericidal versus the bacteriostatic effects . Following 2 days of plaque accumulation, three groups of 10 students rinsed with either 12.0 mM NaF, 0.55 mM CHX plus NaF, or with 2.2 mM CHX plus NaF . Plaque samples were collected before and 90 min after mouthrinsing . The pH in pooled pre- and post-rinse plaque samples was recorded before and up to 10 min after the addition of D-{U-14C}glucose . Total colony-forming units in each sample were determined . High-performance liquid chromatography analyses showed lactate to be the major extracellular glycolytic metabolite in all samples . CHX-NaF markedly reduced the colony-forming units, the pH fall from fermentation of glucose, as well as glucose consumption and lactate formation, whereas NaF alone exhibited no such effects . The reduction of glucose consumption by the CHX-NaF mouthrinses corresponded to the reduction of colony-forming units, indicating no bacteriostatic effect . The plaque pH in vivo was monitored in each student 90 min after mouthrinsing with the test solutions prior to and up to 1 h after a sucrose mouthrinse using touch microelectrodes . The CHX-NaF mouthrinses reduced the fall in pH significantly (p < 0.05) as compared with the NaF mouthrinse.(ABSTRACT TRUNCATED AT 250 WORDS)

Acta Microbiol Immunol Hung, 1995, 42(1), 71 - 5
Simultaneous saccharification and fermentation of rice straw into ethanol; Chadha BS et al.; The physicochemical pretreatment of ball milled rice straw with different oxidizing agents, peracetic acid, alkali-peroxide, manganese-peroxide compounds under steaming pressure were studied . The pretreatment resulted in major changes in chemical composition of rice straw . The peroxide treated substrates were found to be most susceptible to enzymatic saccharification . A maximum saccharification (77.4%) of alkaline-peroxide treated rice straw (5%, w/v) was achieved using cellulase enzyme produced by mixed cultivation of Trichoderma reesei Rut C-30 and Aspergillus ochraceus containing 1.83 FPU, 1.63 cellobiase and xylanase 2.03 IU/ml . The hydrolysate was fermented using coculture of a temperature resistant strain of Saccharomyces cerevisiae and Pachysolen tannophilus resulting in 1.5% (w/v) ethanol . The SSF of 10.0% (w/v) H2O2-MnSO4 treated straw yielded maximum ethanol (2.9%, w/v) after 72 h at 40 degrees C . As a consequence of the well-balanced cellulase production by mixed fungal culture, the supplementation of cellobiase or xylanase was not necessary in the simultaneous saccharification and fermentation process.

Acta Microbiol Immunol Hung, 1995, 42(1), 53 - 9
Hybrid process for ethanol production from rice straw; Chadha BS et al.; A hybrid process for the fermentation of rice straw hydrolysates into ethanol was designed to simultaneously utilize cellulose and hemicellulose fractions of the agro-residue . The process involved dilute acid hydrolysis (for obtaining C-5 sugars) followed by enzymatic saccharification of cellulose enriched fraction with crude cellulase produced by mixed cultures of Trichoderma reesei Rut C-30 and Aspergillus ochraceus IMI 317911 . The fermentation medium containing acid and enzymatic hydrolysate mixture of pentoses and hexoses monomers was fermented with yeast coculture of Saccharomyces cerevisiae and Pachysolen tannophilus resulting in 295.0 ml ethanol/kg of rice straw . The hybrid process resulted in an efficient utilization of both cellulosic and hemicellulosic components of the rice straw for ethanol production.

Verh K Acad Geneeskd Belg, 1995, 57(1), 51 - 74; discussion 74-7
Laxatives and intestinal epithelial cells: a morphological study of epithelial cell damage and proliferation; Geboes K; Experimental studies indicate that anthranoid laxatives may induce epithelial damage . In addition they induce the release of prostaglandins . Epithelial cell damage and release of prostaglandins are two pathways by which epithelial cell proliferation could be influenced . Other laxatives including fermentable laxatives like lactulose may also influence large intestine cell proliferation by the trophic effect of the fermentation products such as short chain fatty acids . For these reasons an in vitro study was performed on human intestinal epithelial cells in culture to investigate the direct damaging effect of rhein anthrone . Ultrastructural examination showed a dose dependent direct damage . In addition an in vivo study in rats was performed to compare the short and long term effect of sennosides, bisacodyl, sodium picosulphate and lactulose on epithelial cell proliferation in the ileum and large intestine . Cell proliferation was examined by the BrdUrd labeling technique after 2, 6 and 12 weeks of continuous treatment . Studies in control animals show that the Labeling Index (LI) is higher in the caecum compared with other segments of the colon, and higher in the ileum than in the colon . Treatment with sennosides, bisacodyl and sodium picosulphate does not influence the LI in the ileum and induces no statistically significant increase of the LI when the treated groups are compared with the control group at the end of the study . The proliferative pattern along the crypts remains unchanged with all the laxatives throughout the study . It appears therefore that 'contact' laxatives have no major influence on ileal and colonic epithelial cell proliferation.

Reprod Nutr Dev, 1995, 35(3), 267 - 75
Effect of type of lucerne hay on caecal fermentation and nitrogen contribution through caecotrophy in rabbits; Garcia J et al.; Seventy-five New Zealand White x Californian rabbits were used to study the influence of the chemical composition of lucerne hay on caecal and caecotrophy characteristics . Five lucerne hays varying in chemical composition were ground and formed into pellets . These were the sole form of nutrition during the experiment . The type of lucerne hay did not affect caecal volatile fatty acid concentration, pattern of fermentation of pH . However, the caecal ammonia concentration decreased linearly (by 30% between extreme diets, P = 0.002) when dietary fibre proportion increased . The weight of caecum and caecal contents increased linearly (by 12%, P = 0.010, and 35%, P < 0.001, respectively, between extreme diets) with dietary fibre proportion . Soft faeces excretion and contribution of soft faeces to dry matter intake were not influenced by the type of lucerne hay . The proportion of caecal content that appeared daily as soft faeces and the total and microbial nitrogen concentrations in soft faeces were higher (42, 14 and 39%, respectively) for the lucerne hay with the lowest dietary fibre proportion than for the average of the other hays.

J Basic Microbiol, 1995, 35(3), 171 - 7
Effect of acetic acid on xylose fermentation to xylitol by Candida guilliermondii; Felipe MG et al.; The effect of acetic acid concentration on xylose-fermentation to xylitol by Candida guilliermondii FTI 20037 was evaluated in semisynthetic medium containing different concentrations of the acid . Increasing acetic acid concentration up to 1.0 g/l favored xylitol yield and productivity, with maximum values of 0.82 g/g and 0.57 g/l.h, respectively . The presence of acetic acid reduced cell production at all concentration . Furthermore, acetic acid was assimilated by the yeast together with the sugars and was depleted from the medium at concentrations of less than 3.0 g/l . The ability of this yeast to assimilate acetic acid suggests that these cells act as agents of medium detoxification . This behavior may lead to a viable microbiological process of xylitol production by C . guilliermondii FTI 20037 using xylose-rich lignocellulosic hydrolysates in which acetic acid is commonly present, causing inhibition of fermentative activity.

J Basic Microbiol, 1995, 35(3), 147 - 55
Kinetic studies on the yeast Phaffia rhodozyma; Acheampong EA et al.; The yeast Phaffia rhodozyma, a promising microbial producer of the carotenoid astaxanthin, was cultivated in batch and continuous processes in an agitated and aerated fermenter using an acid peat extract based culture medium . For the accelerated growth phase, the mean specific growth rate and doubling time were found to be 0.038 h-1, and 18.24 hours, respectively . The production of astaxanthin was found to be basically growth associated, the maximum concentrations of the pigment produced in batch culture and continuous cultivation being similar.

J Anim Sci, 1995 Jan, 73(1), 250 - 6
Preventing in vitro lactate accumulation in ruminal fermentations by inoculation with Megasphaera elsdenii; Kung L Jr et al.; In vitro fermentations containing a mixed culture of ruminal bacteria (ruminal fluid from a hay-fed steer), buffer, and primarily rapidly degradable substrates (starch, glucose, cellulose, cellobiose, and trypticase) were inoculated with an overnight culture of Megasphaera elsdenii B159 . Triplicate flasks were either uninoculated or inoculated to obtain a final concentration of 8.7 x 10(5) and 8.7 x 10(6) colony forming units of M . elsdenii per milliliter of culture fluid . Inoculation with M . elsdenii prevented an accumulation of lactic acid and excessive drop in pH . Lactate peaked at more than 40 mM in untreated cultures . In cultures inoculated with a low dose of M . elsdenii, lactate concentration peaked at approximately 25 mM at 5 h of fermentation but decreased rapidly to less than 5 mM by 7 h of fermentation . With the addition of the high dose of M . elsdenii, lactate was never greater than 2 mM (P < .05) throughout fermentation . Cultures treated with M . elsdenii had greater amounts (P < .05) of isobutyrate, butyrate, isovalerate, and valerate than untreated cultures . After 24 h of fermentation, one-half of the culture fluid was transferred to an equal volume of fresh buffer with substrate but was not inoculated with further quantities of M . elsdenii . Six hours after transfer, cultures that had been originally treated with M . elsdenii had lower (P < .05) amounts of lactate than untreated cultures . Inoculation with M . elsdenii has potential to prevent lactate accumulation in diets containing readily fermentable carbohydrates.

J Anim Sci, 1995 Jan, 73(1), 128 - 35
In vivo study of circadian variations of the cecal fermentation pattern in postweaned and adult rabbits; Bellier R et al.; Two groups of cecal cannulated rabbits (postweaned and adult, 6 and 16 wk of age, respectively) were used to compare the circadian variations of the fermentation pattern . Rabbits were kept in metabolism cages under a 12:12 light-dark schedule (0700 to 1900) . For each rabbit, a total of 12 samples of cecal material were collected (every 12 h) for six consecutive days to cover a 24-h cycle; feed ingestion and hard feces elimination were recorded . For postweaned and adult rabbits, the period of cecotrophy practice was mainly 0400 to 1200, and also 2200 to 2400 for the former and 0800 to 1400 for the later . Compared with those of adult rabbits, the cecal contents of the postweaned rabbits were characterized by a lower DM level (17.6 vs 20.3%; P < .001), a lower VFA level (65.4 vs 86.1 mM; P < .001), and a higher ammonia N level (7.6 vs 6.1%; P = .02) related to the presence of a double period of cecotrophy (only one in the adult rabbits), and corresponding to the postweaning adaptation of the cecal microflora to a dry feed . A lower butyrate molar proportion was found in postweaned than in adult rabbits (10.5 vs 13.6%; P = .004), whereas molar proportion of acetate and propionate remained similar regardless of the age of the rabbit . In the postweaned rabbits, changes in fermentation pattern were related to circadian rhythm of the cecotrophy practice . During this period, the levels of total VFA, acetate, and butyrate progressively decreased; the minimum was reached at 1200 (e.g., 53.8 44.6, and 4.4 mM, respectively); the corresponding propionate:butyrate ratio was 1.0.

Annu Rev Pharmacol Toxicol, 1995, 35, 369 - 90
Cytochromes P450 expression systems; Gonzalez FJ et al.; Catalytically active cytochrome P450 enzymes have been successfully expressed in bacterial, yeast, and mammalian cells . A variety of expression vectors have been used, resulting in both transient and stable expression . The system of choice depends on the goals of a particular project . Factors such as expense, ease of use, and yields required should govern the decision whether to use bacterial, yeast, insect, or mammalian cDNA expression . High-level expression of mammalian P450s in bacteria usually requires modifications of the amino-terminal region of the enzyme . The Escherichia coli P450-OR fusion proteins may also come of age for use in fermentation-production processes for the chemical industry . Many cytochromes P450 have been expressed in yeast, with variable levels of expression . Baculovirus, albeit somewhat tedious in having to individualize expression conditions, can produce high levels of enzyme . The standard mammalian cell expression systems, both transient and stable, have been of tremendous value to drug metabolism and carcinogenesis research and will continue to play a role in these areas.

Ann Trop Paediatr, 1995, 15(1), 61 - 8
Clinical trial of fermented maize-based oral rehydration solution in the management of acute diarrhoea in children; Yartey J et al.; In an effort to identify appropriate fluids available in the home for oral rehydration therapy in Ghana, a study was designed to investigate the efficacy of fermented maize gruel, a popular Ghanaian traditional food, in the management of acute diarrhoea . Altogether 108 children aged between 4 and 27 months presenting with acute diarrhoea at the Princess Marie Louise Children's Hospital in Accra, with mild to moderately severe dehydration, were randomly assigned to treatment with either WHO/UNICEF oral rehydration solution (ORS) or fermented and unfermented maize solutions . About 35 children were admitted to each of the three treatment groups . Treatment with the rehydration fluid was maintained for 24 h . Efficacy of the various treatments, assessed in terms of fluid intake, stool output, stool frequency, weight gain and duration of diarrhoea, showed no significant variation among the three groups . The results indicate that the maize solutions were as effective as WHO/UNICEF ORS for oral rehydration therapy . However, the fermented maize was more readily accepted by the children than the unfermented solution . Because fermented maize gruel is widely consumed, inexpensive, readily available, and culturally acceptable to most communities in Ghana, it may be recommended as an appropriate home-available fluid for the management of acute diarrhoea in children at the community level.

Stomatologiia (Mosk), 1995, 74(3), 12 - 5
{The nature of the distribution and utilization of saccharose in the oral cavity after carbohydrate loading}; Leont'ev VK et al.; Sucrose content on surface of oral tissues and in the oral fluid following a carbohydrate loading was studied in vivo synchronously and over time . The content of sucrose adsorbed by oral tissues was assessed by its desorption with applications . Sucrose concentrations were the highest in the liquid closest to tissues in comparison with its levels in the saliva in general, this indicating a high cariogenic potential of the buccal mucosa due to intake of easily fermented carbohydrates . Prolonged utilisation of adsorbed sucrose to unavailable concentration provides a sufficiently long contact of mineralized tissues with acidogenic solutions, this promoting the development of a cariogenic situation . Search for means to prevent cariogenic situations should be aimed at search for effective desorbents of sucrose from the oral cavity just after its intake.

Microbiol Immunol, 1995, 39(5), 307 - 13
Identification of phosphocholine-containing glycoglycerolipids purified from Mycoplasma fermentans-infected human helper T-cell culture as components of M . fermentans; Matsuda K et al.; Previously, we have reported the occurrence of novel phosphocholine-containing glycoglycerolipids (GGPLs: GGPL-I and GGPL-III) in human helper T-cell (MT-4 cell line) (Mustuda et al, Glycoconjugate J . 10:340) . However, the GGPLs disappeared from the MT-4 after treatment with an antimycoplasma agent . This disappearance suggested the involvement of microorganisms in the GGPL expression . In this paper, we show that the novel lipids are components of Mycoplasma fermentans itself . The supernatant fluid of the antimycoplasma agent-untreated Mt-4 cell culture produced mycoplasma-like colonies on PPLO agar plates, and PCR and immunological methods revealed the presence of M . fermentans . GGPLs were expressed again in the treated Mt-4 cells after infection with the isolated M . fermentans . The isolated M . fermentans had glycoglycerolipids corresponding to GGPL-I and GGPL-III . Thin-layer chromatography-mass spectrometry and immunological analyses showed that these glycoglycerolipid which were derived from the isolated M . fermentans were identical with GGPL-I and GGPL-III previously obtained . This is the first report that shows mycoplasma has phosphocholine-containing glycoglycerolipids.

J Fr Ophtalmol, 1995, 18(5), 356 - 63
{Comparative prospective study of effects of Biovisc and Healonid on endothelial cell loss and intraocular pressure in cataract surgery}; Colin J et al.; PURPOSE: The goal of this trial was to evaluate the efficacy (protective action on corneal endothelium and ability to facilitate the procedure) as well as safety (effect on intraocular pressure and inflammation) of Biovisc (new viscoelastic agent made of 1% sodium hyaluronate produced by bacterial fermentation) versus Healonid) postcataract surgery (manual or phacoemulsification) . METHODS: 106 patients, 45 males and 61 females (31-94 years) were included in this prospective randomized multicentre trial and followed up for three months . Specular microscopy and intraocular pressure (IOP) measurement were the main evaluation criteria . RESULTS: At D 90, no significant difference was observed between the two viscoelastic agents on the mean endothelial cell loss (group Viovis: -8.6%; group Healonid: -6%) as well as on IOP (early peaks were transitory and resolutive) . CONCLUSION: Biovisc and Healonid were similar in terms of efficacy and tolerance.

Reprod Nutr Dev, 1995, 35(4), 375 - 86
Relationships between microflora and caecal fermentation in rabbits before and after weaning; Padilha MT et al.; Some microbiological and biochemical parameters of caecal content were studied in 15- to 49-d-old rabbits that were slaughtered sequentially . The ammonia level did not differ before weaning (11.5 mmol/L on average) (P = 0.41) or after weaning (7.4 mmol/L on average) (P = 0.19) but decreased by 40% (P < 0.001) between days 29 and 32 . The level of pH decreased linearly (P < 0.001) throughout the period studied . The Escherichia coli counts decreased up to weaning (P < 0.001) and was then not significantly affected by age (P = 0.12) . The total volatile fatty acid (VFA) concentration increased between days 15 (8.2 mmol/L) and 25 (33.9 mmol/L) (P < 0.05) and then levelled off below 40 mmol/L . Molar proportions in propionate and in branched-chain fatty acid (BCFA) and valeric acid were high at day 15 but decreased when the animals began to eat solid feed . The C3/C4 ratio reversed at weaning (3.8 on day 15 and 0.5 on day 49) whereas the acetic acid proportion was not affected by age (P = 0.19) . High counts of anaerobic microflora were found between 15 and 22 d of age (10(11) bacteria/g of caecal content, on average) and did not change significantly according to the age (at about 10(10) bacteria/g), from day 29 until the end of the experiment (P = 0.29) . Amylolytic flora had a similar evolution at a slightly lower level . In contrast, under our breeding conditions cellulolytic microflora slowly colonized the caecum and remained at a low level . The discriminant analysis revealed relationships between ages, intestinal microflora and fermentation parameter; the colibacilli flora was associated with mother-fed animals and amylolytic flora which was linked to BCFA and valeric acid, while the cellulolytic flora was associated with animals older than 4 weeks and linked to the production of C2, C3, C4 and ammonia.

Reprod Nutr Dev, 1995, 35(4), 353 - 65
{Adaptation of rumen fermentation to monensin}; Mbanzamihigo L et al.; Adaptation of rumen fermentation to monensin feeding has been studied with rumen-fistulated sheep receiving a daily dose of 30 mg of monensin for a period of 21 d followed by a 28 d period during which 60 mg doses were administered . The ration consisted of 300 g of hay and 300 g of concentrates, fed at 9.00 h and 16.00 h . Monensin was placed in the rumen as an aqueous suspension, just prior to the morning feeding . Monensin infusion was preceded and followed by a period during which no monensin was infused . The following rumen fermentation parameters were determined: methane production, pH, volatile fatty acids (VFA) molar proportions, total volatile fatty acid concentration, lactate and ammonia concentrations and in sacco degradability of hay . Rumen gas expelled through the fistula was collected for 6 h per day and analysed . Total VFA concentration, molar proportions of individual VFA, pH, lactate and ammonia concentration were determined on rumen contents, sampled just prior the administration of monensin and 2 and 6 h later . In vitro incubations of 3 h were carried out with rumen fluid, sampled 1 h after feeding . In vivo and in vitro methane production was decreased by monensin feeding . The molar proportion of propionate in the rumen was increased, while acetate and butyrate percentages were lowered . The total VFA and ammonia concentrations were also decreased by monensin, but pH values were increased . In vitro production of propionate was stimulated by monensin administration and methanogenesis decreased . The organic matter in sacco degradability was not affected, probably because of the time difference between the introduction of bags and monensin in the rumen . These modifications of rumen fermentation persisted as long as monensin was given, indicating that in this experiment, there was no adaptation to the ionophore.

Reprod Nutr Dev, 1995, 35(2), 121 - 8
{In vitro simulation of rabbit cecal fermentation in a semi- continuous flow fermentor . III . Effect of the quantity of dry matter introduced daily in the fermentor and reproducibility of the method}; Adjiri D et al.; In a preliminary experiment, 3 Rusitec-like fermentors of 1 L capacity were operated under identical conditions . The only difference was the quantity to treated substratum introduced daily into each fermentor: 15 g/d (M15); 40 g/d (M40); and 60 g/d (M60) on a dry matter basis . The fermentation substratum was a rabbit feed that had been digested with amylase and pepsin . The organic matter was lost over 48 h at a significantly higher rate in the M15 fermentor than in M40 and M60: 30.4%, 19.7% and 17.3%, respectively . The pH values observed in M40 and M60 (5.99 and 5.83) were similar to that observed in vivo under ad libitum feeding conditions . The pH was higher in M15 (6.7), as observed in vivo with restricted animals just before the daily meal . The volatile fatty acids (VFA) proportions for C2, C3 and C4 were similar to the in vivo proportion for the 3 fermentors . The daily total VFA production was the largest with M40 but was associated with a poor stability and an excess of minor VFAs . The introduction of 15 g/d was preferred by the authors because of organic matter disappearance rate, pH stability and VFA production . In a second experiment, 4 fermentors were used in the same way as the M15 one, in order to study the reproducibility of the method . Small but significant differences between fermentors were observed for all parameters in relation to a high fermentor stability from 1 day to the next.(ABSTRACT TRUNCATED AT 250 WORDS)

Eur J Morphol, 1995 Jan, 33(1), 59 - 70
Light microscopic studies of the stomach of the lesser mouse deer (Tragulus javanicus); Agungpriyono S et al.; The stomach of the lesser mouse deer was studied at the light microscopic level using histological and immunohistochemical methods . The stomach was clearly differentiated into rumen, reticulum including reticular groove, a small transition zone and abomasum . The mucosal surface of the rumen, reticulum and transition zone was lined with a stratified squamous epithelium and that of the abomasum with a simple columnar type . The epithelial keratinization was weak in the rumen, floor of the reticular groove and transition zone, while it was strong in the reticulum, especially on the tip of the reticulum papillae . Large sinusoidal capillaries were often present in the ruminal papillae . In the ruminal mucosa, a thin layer of alpha-smooth muscle actin immunoreactive cells was demonstrated by immunohistochemistry . The muscularis mucosae of the reticulum was continuous and well-developed . The transition zone appeared as a nonglandular area having many low mucosal folds and two layers of tunica muscularis . The abomasal mucosa consisted of cardiac, proper gastric and pyloric glands . Cells immunoreactive for bovine pepsinogen and bovine prochymosin antisera were demonstrated in the abomasum . It is suggested that the characteristic features observed might be adaptations to a relatively rapid passage and rapid absorption of the fermentation products . There is some evidence that the transition zone is not a part of either the floor of the reticular groove or the abomasum, suggesting a possible reevaluation of the term used for the reticulo-abomasal orifice in the mouse deer.

Acta Vet Hung, 1995, 43(2-3), 229 - 46
Effect of avoparcin on rumen fermentation and duodenal nutrient flow in sheep; Febel H et al.; In a digestive-physiological experiment series, the effect exerted by avoparcin on rumen fermentation and on the ruminal digestion of nutrients was studied in wethers provided with rumen and duodenal cannulas, as a function of the composition of feed as substrate . Three control (I, II, III) groups containing different amounts of rumen degradable protein (RDP) and nonstructural carbohydrate (NSC) were formed (composition of diet: group I, 74% RDP and 38% NSC; group II, 57% RDP and 32% NSC; group III, 48% RDP and 23% NSC) . The feeding of control diets was followed by the administration of experimental diets containing avoparcin (groups I+A, II+A, and III+A) . The dose of avoparcin was 0.75 mg/kg body weight . Irrespective of the RDP and NSC content of the feed, avoparcin reduced the molar ratio of acetic acid and increased that of propionic acid, decreased the acetic acid/propionic acid ratio, and increased the molar ratio of isobutyric acid . Ammonia concentration of the ruminal fluid was significantly lower in group I+A than in the corresponding control group (I) . Avoparcin supplementation of diet III improved the apparent digestibility of organic matter from 52.9% to 56.4% . When added to a ration of high NSC and RDP content (I), avoparcin decreased the true digestibility of organic matter from 77.0 to 72.5% . Compared to diet III as well as to diets II and III, avoparcin significantly increased the ruminal degradation of cellulose and hemicellulose, respectively . Avoparcin supplementation of the diet significantly decreased the microbial N content of the duodenal chymus irrespective of the NSC and RDP content of the diet . In group I+A, the amount of dietary N passed from the rumen into the duodenum in 24 h was significantly higher (7.1 g/day vs . 2.7 g/day) . In wethers fed the diet of the lowest NSC and RDP content (III), avoparcin supplementation (III+A) increased the apparent digestibility of N in the rumen . In contrast, in wethers fed diets of higher RDP and NSC content (I and II) the true ruminal digestibility of N decreased . Irrespective of the RDP and NSC content of the diet, avoparcin supplementation significantly reduced the efficiency of microbial protein synthesis . The enhanced propionic fermentation induced by the administration of avoparcin allows more efficient utilization of the dietary energy . The higher ratio of undergraded, bypass protein reaching the duodenum provides the animal with a protein source degraded and utilized directly in the small intestine . The results support the observation that avoparcin increases the body weight gain of animals during fattening.

Vopr Pitan, 1995, (4), 17 - 9
{The effect of fermented hydrolyzed whey enriched with lactates on the morphological structure of the internal organs in laboratory animals}; Lind AR et al.; Results of pathomorphological investigation of rat organs fed during 1 and 3 months the diet containing 8% of protein as milk whey protein partly hydrolysed by enzymes and enriched by lactates (SGOL-1) are presented . The conducted investigation have not revealed of pathological effect of a product SGOL-1 on morphological structures of investigated internal bodies and tissues of the laboratory animals . A increase of body mass of animals and contents of RNAS in cells of practically all bodies and tissues of the animals were also marked.

Stomatologiia (Mosk), 1995, 74(2), 20 - 2
{The effect of mineral and organic substances on the desorption of sugar from a soft dental deposit}; Leont'ev VK et al.; Effects of the principle mineral and mineralizing components of the saliva, alimentary organic acids-products of carbohydrate metabolism, and of some other substances of various pH on sugar desorption from soft dental deposit were compared in vitro . The desorbing efficacy was assessed from the concentration of sucrose, derived from a sample of lyophilized dental deposit, in a suspension of the tested reagent . The major mineral components of the saliva, calcium and phosphate, were found to promote extraction of sucrose from the deposit in neutral and weakly alkaline media . Acid medium also favors sucrose desorption . Due to the physiological nature and efficacy of sucrose desorption, solutions of alimentary organic acids may be recommended for prevention of cariogenic situations caused by intake of easily fermented carbohydrates.

Nahrung, 1995, 39(4), 282 - 7
Fermentation of rice-bengal gram dhal blends with whey: changes in phytic acid content and in vitro digestibility of starch and protein; Sharma A et al.; Whey fermentation of various rice and bengal gram dhal blends prepared by mixing them in different proportions at 35 degrees C for 18 h brought about a significant decline in phytic acid content . Phytic acid content in various blends decreased to the extent of 23 to 36 per cent over the control values . Whey incorporation as well as fermentation improved the starch and protein digestibility (in vitro) of all the rice-bengal gram dhal mixtures . Improvement in starch and protein digestibility is related to the reduction in phytic acid content, as this antinutrient is known to inhibit amylolysis and proteolysis . A significant negative correlation found between phytic acid and digestibility of starch and protein strengthens our findings.

J Biol Chem, 1994 Dec 30, 269(52), 33123 - 8
Structure of a novel phosphocholine-containing glycoglycerolipid from Mycoplasma fermentans; Matsuda K et al.; Mycoplasma fermentans is thought to be a pathogen of rheumatoid arthritis or cofactor of AIDS . A novel phosphocholine-containing glycoglycerophospholipid named GGPL-I was isolated from a M . fermentans-infected human helper T-cell culture . It was revealed that GGPL-I is a lipid component of the M . fermentans and a major immunological determinant . The GGPL-I was purified by DEAE-Sephadex column chromatography and repeated Iatrobeads column chromatography . The purified glycophospholipid was subjected to structural characterization by thin-layer chromatography, Fourier-transform infrared spectrometry, liquid secondary ion mass spectrometry, and nuclear magnetic resonance spectroscopy . Its structure was determined to be as follows: 6'-O-phosphocholine-alpha-glucopyranosyl-(1'-3)-1,2-diacyl-sn-glycerol . This glycoglycerophospholipid is unique in containing phosphocholine, which is attached to C-6 of glucose . The stereospecific numbering (sn) of naturally occurring GGPL-I was determined through comparison with chemically synthesized compounds.

Proc Natl Acad Sci U S A, 1994 Dec 20, 91(26), 12872 - 6
Determination of the absolute configuration of (+)-neopentyl-1-d alcohol by neutron and x-ray diffraction analysis; Yuan HS et al.; The absolute configuration of (+)-neopentyl-1-d alcohol, prepared by the reduction of 2,2-dimethylpropanal-1-d by actively fermenting yeast, has been determined to be S by neutron diffraction . The neutron study was carried out on the phthalate half ester of neopentyl-1-d alcohol, crystallized as its strychnine salt . The absolute configuration of the (-)-strychninium cation was first determined by an x-ray anomalous dispersion study of its iodide salt . The chiral skeleton of strychnine then served as a reference from which the absolute configuration of the -O-CHD-C(CH3)3 group of neopentyl phthalate was determined . Difference Fourier maps calculated from the neutron data showed unambiguously that the -O-CHD-C(CH3)3 groups of both independent molecules in the unit cell had the S configuration . This work proves conclusively that the yeast system reduces aldehydes by delivering hydrogen to the re face of the carbonyl group . Crystallographic details: (-)-strychninium (+)-neopentyl-1-d phthalate, space group P2(1) (monoclinic), a = 18.564(6) A, b = 7.713(2) A, c = 23.361(8) A, beta = 94.18(4) degrees, V = 3336.0(5) A3, Z = 2 (T = 100 K) . Final agreement factors are R(F) = 0.073 for 2768 reflections collected at room temperature (x-ray analysis) and R(F) = 0.144 for 960 reflections collected at 100 K (neutron analysis).

Arch Latinoam Nutr, 1994 Dec, 44(4), 270 - 3
{Chemical changes in colostrum fermented with sorghum}; Diaz Cruz A et al.; Colostrum from Holstein cows was collected during the first three days post partum . Ground sorghum (7.5%) was added to it . Untreated colostrum used as control, and sorghum treated colostrum samples were allowed to ferment for 0, 8 or 21 days at 18-20 degrees C in glass containers; pH, moisture, crude protein, digestible protein, ammonia, lactic acid and total energy were analyzed in untreated and treated samples . Crude protein was not significantly different (P > 0.01) in control colostrum (7.12, 5.76, 5.70%) and treated colostrum (6.66, 5.71, 5.98%) at 0, 8 and 21 days of fermentation respectively . Digestible protein was higher (P < 0.01) in the untreated (90.0, 93.0%) than in the treated colostrum (89.0, 81.0, 86.0%) . Ammonia content was also higher (P < 0.01) in the control (0.25, 1.31, 1.37%) than in the treated one (0.23, 0.97, 1.20%) . Lactic acid was lower (P < 0.01) in the untreated colostrum (0.82 g/100 ml) than in the treated colostrum (1.24 g/100 ml) after 21 days of fermentation . Total energy values were lower (P < 0.01) at 8 and 21 days of fermentation in the untreated (0.91, 0.84 Kcal/g) than in the treated colostrum (1.16, 0.97 Kcal/g) . The addition of sorghum to colostrum reduced the crude, protein degradation and the ammonia content after 8 and 21 days of fermentation, increasing total energy and lactic acid content after 21 days of fermentation.

J Bacteriol, 1994 Dec, 176(24), 7423 - 9
The mutation DGT1-1 decreases glucose transport and alleviates carbon catabolite repression in Saccharomyces cerevisiae; Gamo FJ et al.; Glucose in ethanol-glycerol mixtures inhibits growth of Saccharomyces cerevisiae mutants lacking phosphoglycerate mutase . A suppressor mutation that relieved glucose inhibition was isolated . This mutation, DGT1-1 (decreasing glucose transport), was dominant and produced pleiotropic effects even in an otherwise wild-type background . Growth of the DGT1-1 mutant in glucose was dependent on respiration, and no ethanol was detected in the medium within 7 h of glucose addition . When grown on glucose, the mutant had a reduced glucose uptake and both the low- and high-affinity transport systems were affected . In galactose-grown cells, only the high-affinity glucose transport system was detected . This system had similar kinetic characteristics in the wild type and in the mutant . Catabolite repression of several enzymes was absent in the mutant during growth in glucose but not during growth in galactose . In contrast with the wild type, the mutant grown in glucose had high transcription of the glucose transporter gene SNF3 and no transcription of HXT1 and HXT3 . Expression of multicopy plasmids carrying the HXT1, HXT2, or HXT3 gene allowed partial recovery of both fermentative capacity and catabolite repression in the mutant . The results suggest that DGT1 codes for a regulator of the expression of glucose transport genes . They also suggest that glucose flux might determine the levels of molecules implicated as signals in catbolite repression.

Dig Dis Sci, 1994 Dec, 39(12 Suppl), 37S - 40S
Feedback regulation and sensation; Read NW; The gut is a long tube; food goes down it and across it . Its purpose is to process the food that is consumed in order to optimize absorption of nutrients . It works rather like the reverse of an assembly line in a manufacturing plant with different regions of the gastrointestinal tube specialized sequentially for storage, acid digestion, alkaline digestion, absorption, fermentation, and disposal of waste products . Like an assembly line, it will only work efficiently if the delivery of material to the next process in coordinated closely with the optimum rate of that process . In the gut, the delivery of material is achieved by the propulsive activity of the gastrointestinal smooth muscle, which is in turn programmed by the enteric nervous system and orchestrated by neurohumoral responses to the content of the digesta . It is a finely tuned system; any disturbance can impair absorption and give rise to abdominal discomfort . The stomach is a key organ in the "gastrointestinal dissembly line," It not only commences the digestive process under highly acidic conditions, it stores the masticated food as in a hopper, delivering the acidic digesta or chyme into the duodenum at a rate that is commensurate with the rate at which it can be digested and the products of digestion can be absorbed . The rate at which material enters the small intestine is crucial to achieving optimum nutrition; too fast, and it overwhelms the functional capacity of the small intestine, causing malabsorption and diarrhoea; too slow, and it inhibits the consumption of another meal . The gastrointestinal tract can normally process three medium-sized meals a day.

Am J Clin Nutr, 1994 Dec, 60(6 Suppl), 1068S - 1070S
Sensory properties of chocolate and their development; Hoskin JC; Sensory attributes of eating chocolate are determined by processing variables and inherent characteristics of the cocoa bean . Flavor precursors develop during fermentation and primarily interact at roasting temperatures . Complex browning reactions occur during roasting . Numerous heterocyclic flavor compounds produced then contribute to the characteristic chocolate flavor . Feel of chocolate in the mouth (mouth feel) and textural properties are determined by the unique properties of cocoa butter . Careful processing and selection of ingredients is necessary to produce desirable attributes.

Indian J Exp Biol, 1994 Dec, 32(12), 865 - 8
Development of a mutant strain of Aspergillus niger and optimization of some physical factors for improved calcium gluconate production; Ray S et al.; In the course of mutation studies of Aspergillus niger strain AB with ethylene imine (1:4000), a mutant A . niger AB 501, produced greater amount of calcium gluconate in the culture broth (88.0 g/lit) as against the parent strain (36.0 g/lit) by the surface culture method of fermentation . This mutant was then exposed to UV-rays and a mutant, A.niger AB 1801, was found to produce high calcium gluconate in the culture broth (120 g/lit) . The optimum cultural conditions for the production of calcium gluconate by A.niger AB 1801 were pH, 6.5; period of incubation, 9 days; volume of medium in 1 litre flask, 150 ml; temperature, 30 degrees C, volume of inoculum, 7.5 ml of cell suspension containing 2.6 x 10(7) spores and age of inoculum, 6 days old spores of A . niger AB 1801 . The maximum yield of calcium gluconate to the above conditions was 168 g/lit . The cultural conditions that support maximum cultural growth did not, however, give optimal yield of calcium gluconate because after having yielded the maximum of calcium gluconate the growth of organism continued to increase further.

Genetics, 1994 Dec, 138(4), 1005 - 13
The yeast CCR4 protein is neither regulated by nor associated with the SPT6 and SPT10 proteins and forms a functionally distinct complex from that of the SNF/SWI transcription factors; Denis CL et al.; The CCR4 protein is specifically required for the increased transcription at the ADH2 locus resulting from mutations in the SPT10 (CRE1) and SPT6 (CRE2) genes and is also required for the expression of ADH2 and other genes under non-fermentative growth conditions . The mechanism by which mutations in CCR4 suppress defects in SPT10 and SPT6 was examined . The SPT10 and SPT6 genes were shown not to control CCR4 mRNA or protein expression nor did SPT10 and SPT6 proteins co-immuneprecipitate with CCR4 . CCR4 association with two other proteins, 195 and 185 kDa in size, was unaffected by either spt10 or spt6 mutations . Also, the ability of CCR4 to activate transcription when fused to the LexA DNA binding domain was not specifically enhanced by defects in either SPT10 or SPT6 . These results suggest that SPT10 and SPT6, in negatively regulating transcription at ADH2, act through a factor that requires CCR4 function, but do not regulate CCR4 expression, control its activity, physically interact with it, or affect its binding to other factors . The relationship of CCR4 to the group of general transcription factors, SNF2, SNF5, SNF6 and SWI1 and SWI3, which comprise a multisubunit complex required for ADH2 and other genes' expression, was also examined . CCR4 protein expression was not controlled by these factors nor did they co-immuneprecipitate or associate with CCR4 . In addition, a ccr4 mutation had little effect on an ADH2 promoter alteration in contrast to the large effects displayed by mutations in SNF2 and SNF5 . These data suggest that CCR4 acts by a separate mechanism from that used by the SNF/SWI general transcription factors in affecting gene expression.

Anal Biochem, 1994 Dec, 223(2), 198 - 204
Capillary electrophoretic analysis of serine hydroxymethyltransferase in Escherichia coli fermentation broth; Strege MA et al.; Serine hydroxymethyltransferase (SHMT) expressed in Escherichia coli was analyzed in fermentation broth through the use of capillary electrophoresis (CE), a method which provided advantages over the traditional techniques of slab gel electrophoresis and chromatography . In addition, via CE the difficult resolution and quantitation of SHMT holoenzyme and apoenzyme were achieved . Using this method, a pyridoxal-5'-phosphate (PLP) cofactor/SHMT dimer molar ratio of 0.65 was estimated to be present in holoenzyme in the absence of excess PLP . This determination correlated well with results obtained by other techniques, including electrospray ionization mass spectrometry (ESI-MS) . CE and ESI-MS analyses both provided evidence for significant differences between the folded conformations of SHMT holoenzyme and apoenzyme.

Poult Sci, 1994 Dec, 73(12), 1881 - 6
Digestibility of water-soluble pectin and organic acid losses in intact or cecectomized adult cockerels; Carre B et al.; Two experimental diets consisting of a basal diet either undiluted or diluted with 1% pectin-based gelling agent were given to intact or cecectomized adult cockerels for a balance experiment . The digestibilities of the water-soluble added pectin were 83.2 and 61.4% in intact and cecectomized birds (P < .05), respectively . Lactic acid excretion varied from 407 to 2,692 mg/kg, acetic acid from 790 to 1,214 mg/kg, propionic acid from 108 to 240 mg/kg, and butyric acid from 50 to 90 mg/kg dry matter intake . Organic acid excretions were the lowest for intact birds fed the basal diet and the highest for cecectomized birds fed the pectin diet . Addition of pectin induced an increase (P < .001) in organic acid excretion, especially for lactic acid in cecectomized birds . Organic acid excretion was greater (P < .001) in cecectomized than in intact cockerels . The increase in organic acid excretion induced by pectin addition amounted to 9 and 62% of the digested fraction of pectin in intact and cecectomized cockerels, respectively . The results showed the water-soluble nonstarch polysaccharides to be digested both in ceca and upper tract . It was also shown that the major part of organic acids produced from fermentation are absorbed in the ceca.

Protein Expr Purif, 1994 Dec, 5(6), 534 - 40
A fermentor culture for production of recombinant phenol hydroxylase; Waters S et al.; Fermentor cultures using the fed-batch technique produced the FAD-containing enzyme phenol hydroxylase (EC 1.14.13.7) originated in the lower eukaryote Trichosporon cutaneum, but expressed in Escherichia coli under the control of the tac promoter . At 30 degrees C and isopropyl beta-D-thiogalactopyranoside (IPTG) concentrations of 0.5-2 mM, the enzyme protein was expressed to high cellular content, but aggregated into inclusion bodies . At 25 degrees C similar levels of enzyme protein were synthesized after induction with 0.05 mM IPTG, but a soluble, active enzyme was obtained . The active enzyme was produced at up to 45% of total protein and constituted more than 50% of soluble protein . The total yield was 5 g x liter-1 . The FAD content of the cells increased after induction at a rate not limiting the formation of active enzyme . The enzyme was purified in two chromatographic steps . The N-terminal amino acid residue and the kinetic properties of the purified recombinant enzyme were similar to those reported for the enzyme from T . cutaneum.

Plant Physiol, 1994 Dec, 106(4), 1575 - 82
Differential induction of mRNAs for the glycolytic and ethanolic fermentative pathways by hypoxia and anoxia in maize seedlings; Andrews DL et al.; Fructose-1,6-biphosphate aldolase (ALD) and enolase (ENO) from the glycolytic pathway and pyruvate decarboxylase (PDC) and alcohol dehydrogenase 2 (ADH2) from the ethanolic fermentative pathway, are enzymes previously identified as among those synthesized selectively in O2-deficient roots of maize (Zea mays L.) . The present study measured levels of transcripts representing these two pathways in 5-mm root tips, root axes (the remainder of the primary seminal root), and shoots of maize seedlings to determine how closely both pathways were co-induced and how they were modulated by changes in O2 concentration . In hypoxic seedlings with the roots in solution sparged with 5% (v/v) O2 (balance N2) and the shoots in the same gaseous atmosphere, mRNAs for Pdc1 and Adh2 in root tips both increased about 15-fold during the first 12 h, followed by a decline toward initial levels by 18 to 24h . Message levels for Ald1 and Eno1 showed only small changes during hypoxia . When expression was examined under anoxia, the extent to which all four mRNAs increased in different tissues depended on whether the seedlings had been previously acclimated to hypoxia or were anoxically shocked . The results show that although all the genes examined increased expression during hypoxia and/or anoxia, they differed in the rapidity and magnitude of the response and in the time to reach maximal message levels: there was no common pattern of change of message levels for the glycolytic or for the fermantative enzymes.

J Antibiot (Tokyo), 1994 Dec, 47(12), 1466 - 72
Berninamycins B, C, and D, minor metabolites from Streptomyces bernensis; Lau RC et al.; Berninamycins B, C, and D were isolated from fermentation of Streptomyces bernensis and their structures were studied with 13C NMR and FAB mass spectrometry . Berninamycin B has a valine unit in its cyclic peptide loop instead of the beta-hydroxyvaline unit found in berninamycin A . Berninamycin D has two fewer dehydroalanine units attached to the carboxyl carbon of the pyridine ring . Based on FAB-MS results, berninamycin C is postulated to have only one dehydroalanine unit attached to the carboxyl carbon of pyridine . The biogenesis of berninamycins B, C, and D is discussed.

J Antibiot (Tokyo), 1994 Dec, 47(12), 1442 - 6
Physiological studies on gentamicin: phosphate repression of antibiotic formation; Obregon AM et al.; The effect of inorganic phosphate on the fermentative production of gentamicin by Micromonospora purpurea has been studied using a chemically defined medium . Phosphate concentrations higher than 5.75 mM (1 g/liter-1) did not inhibit growth but specifically prevented antibiotic formation . Changes in the pH medium and carbon or nitrogen depletion were excluded as the cause of antibiotic underproduction . The use of a phosphate analogue, a protein synthesis inhibitor and the profiles of differential rate of antibiotic production suggested that phosphate itself transiently repressed gentamicin formation . Phosphate affected the formation of 2-deoxystreptamine from 2-deoxyinosose, a none phosphorylated substrate.

J Antibiot (Tokyo), 1994 Dec, 47(12), 1434 - 41
Martinomycin, a new polyether antibiotic produced by Streptomyces salvialis . I . Taxonomy, fermentation and biological activity; Bernan VS et al.; Actinomycete culture LL-D37187 has been found to produce the new polyether antibiotic martinomycin . Taxonomic studies, including morphological, physiological, and cell wall chemistry analyses, revealed that culture LL-D37187 is a novel streptomycete species, and the proposed name is Streptomyces salvialis . Martinomycin exhibits activity against the Southern Army Worm (Spodoptera eridania) and Gram-positive bacteria.

J Antibiot (Tokyo), 1994 Dec, 47(12), 1395 - 401
Isolation and characterization of a new 12-membered macrolide FD-895; Seki-Asano M et al.; During the course of our screening program for natural product drugs effective against multidrug resistant cells by using adriamycin resistant HL-60 cells, we have discovered a new 12 membered macrolide FD-895 in the fermentation broth of Streptomyces hygroscopicus A-9561 isolated from a soil sample collected at Iriomote Island, Okinawa prefecture, Japan . FD-895 showed stronger cytocidal activities against in vitro tumor cell lines than adriamycin . FD-895 had the same IC50 values against parent and adriamycin resistant HL-60 cells.

J Antibiot (Tokyo), 1994 Dec, 47(12), 1369 - 75
Panclicins, novel pancreatic lipase inhibitors . I . Taxonomy, fermentation, isolation and biological activity; Mutoh M et al.; Panclicins A, B, C, D, and E are novel pancreatic lipase inhibitors isolated from Streptomyces sp . NR 0619 . Structurally, panclicins A, B, C, D, and E are analogues of tetrahydrolipstatin (THL), which contains a beta-lactone and a N-formyl leucine ester, and the IC50s of panclicins A, B, C, D, and E for porcine pancreatic lipase are 2.9, 2.6, 0.62, 0.66, and 0.89 microM, respectively . The potency of the inhibitory activity of each compound is attributed to the amino acid moiety of each structure . The panclicins are either glycine-type compounds such as panclicins C, D, E, which are two to threefold more potent than THL, or they are alanine-type compounds such as panclicins A and B, which are less potent than the glycine compounds . The inhibitory profiles of the panclicins for other lipases such as post-heparin plasma lipases and bacterial lipases are similar to those for pancreatic lipase . Panclicins A, B, C, D, and E, in a manner similar to THL, irreversibly inhibit pancreatic lipase . However, the compounds don't irreversibly inhibit the enzyme as strongly as THL does.

J Antibiot (Tokyo), 1994 Dec, 47(12), 1359 - 64
FR901451, a novel inhibitor of human leukocyte elastase from Flexibacter sp . I . Producing organism, fermentation, isolation, physico-chemical and biological properties; Fujita T et al.; A novel human leukocyte elastase (HLE) inhibitor, FR901451 was discovered in the fermentation broth of a bacteria . The bacteria was identified as Flexibacter sp . No . 758 . FR901451 has a molecular weight of 1269 and a molecular formula of C60H79N13O18 . The mode of inhibition against HLE is competitive, with a Ki value of 9.8 x 10(-9) M.

J Cardiovasc Surg (Torino), 1994 Dec, 35(6 Suppl 1), 189 - 91
The mitral valve replacement by the new-type bioprostheses (features of design and long-term results); Dzemeshkevich SL et al.; The BAKS bioprostheses were created in our centre and they have the following features: (1) to reduce immunogenicity they underwent a combined fermentochemical treatment which resulted in the native xenovalve consisting of collagen and elastic fibres only; (2) in cutting out the valve the natural aortic sinuses were preserved; and (3) the xenovalve was fixed on a functional frame of an original design . From 1979, BAKS have been implanted in 243 patients with the isolated mitral valve reumatic injury . The patients age varied from 11 to 59 years; 91 patients (37.5%) were under 35 years . The 12-year survival rate (without hospital lethality) was 65.5 +/- 5.3% . The most serious longterm complications were: infectious endocarditis (3.14 patients/years); spontaneous degeneration of bioprosthetic cusps (2.24% patients/years); thromboembolism (0.6% patients/years) . The morphological examination of bioprostheses removed in reoperations from 10 days to 10 years after implantation was performed in 51 cases . Most often, collagen degeneration occurred in patients under 35 . The pathologic structural changes originated because of the localized saturation of bioprosthetic cusps with the recipient plasma proteins, gradual disintegration of collagen fibres, and further calcification of that area . The indications to the mitral valve replacement by BAKS were: the left atrium thrombosis, thromboembolytic syndrome, contraindications to anticoagulation therapy, and the age over 35 years.

Microbiologia, 1994 Dec, 10(4), 403 - 12
Sibling species of the Saccharomyces sensu stricto complex in Spain; Naumov GI et al.; By genetic hybridization, molecular karyotyping and Southern hybridization with the ADC1 promoter probe three species Saccharomyces cerevisiae, S . paradoxus and S . bayanus were identified among wild Saccharomyces sensu stricto yeast in Spain . Wine strains fermenting melibiose belong to the biological species S . bayanus (syn . S . uvarum) . S . kluyveri has been detected karyotypically.

Biodegradation, 1994 Dec, 5(3-4), 237 - 48
Microbes, enzymes and genes involved in dichloromethane utilization; Leisinger T et al.; Dichloromethane (DCM) is efficiently utilized as a carbon and energy source by aerobic, Gram-negative, facultative methylotrophic bacteria . It also serves as a sole carbon and energy source for a nitrate-respiring Hyphomicrobium sp . and for a strictly anaerobic co-culture of a DCM-fermenting bacterium and an acetogen . The first step of DCM utilization by methylotrophs is catalyzed by DCM dehalogenase which, in a glutathione-dependent substitution reaction, forms inorganic chloride and S-chloromethyl glutathione . This unstable intermediate decomposes to glutathione, inorganic chloride and formaldehyde, a central metabolite of methylotrophic growth . Genetic studies on DCM utilization are beginning to shed some light on questions pertaining to the evolution of DCM dehalogenases and on the regulation of DCM dehalogenase expression . DCM dehalogenase belongs to the glutathione S-transferase supergene family . Analysis of the amino acid sequences of two bacterial DCM dehalogenases reveals 56% identity, and comparison of these sequences to those of glutathione S-transferases indicates a closer relationship to class Theta eukaryotic glutathione S-transferases than to a number of bacterial glutathione S-transferases whose sequences have recently become available . dcmA, the structural gene of the highly substrate-inducible DCM dehalogenase, is carried in most DCM utilizing methylotrophs on large plasmids . In Methylobacterium sp . DM4 its expression is governed by dcmR, a regulatory gene located upstream of dcmA, dcmR encodes a trans-acting factor which negatively controls DCM dehalogenase formation at the transcriptional level . Our working model thus assumes that the dcmR product is a repressor which, in the absence of DCM, binds to the promoter region of dcmA and thereby inhibits initiation of transcription.

Biosci Biotechnol Biochem, 1994 Dec, 58(12), 2164 - 7
Pyruvic acid production by an F1-ATPase-defective mutant of Escherichia coli W1485lip2; Yokota A et al.; An F1-ATPase-defective mutant, TBLA-1, was constructed by the transduction of a defective gene for the alpha subunit of F1-ATPase, atpA401, into Escherichia coli W1485lip2, a lipoic acid-requiring pyruvic acid producer . The pyruvic acid production of the strain TBLA-1 was found to be improved markedly compared with that of strain W1485lip2 . In cultures using a jar fermentor, the strain W1485lip2 consumed 50 g/liter of glucose and produced 25 g/liter of pyruvic acid after culture for 32h, while strain TBLA-1 consumed the same amount of glucose, and produced more than 30 g/liter of pyruvic acid in a 24-h culture . A revertant, No . 63-1, derived from the strain TBLA-1, had a normal level of F1-ATPase activity, and showed a similar pattern of pyruvic acid production to that of strain W1485lip2.

Lett Appl Microbiol, 1994 Dec, 19(6), 486 - 8
Penicillin production by Penicillium nalgiovense; Andersen SJ et al.; A large number of Penicillium nalgiovense strains were found to be as good penicillin producers on optimal production media as strains of Penicillium chrysogenum . It is not known whether penicillin can be produced on fermented sausages, but selection for non-penicillin producing fermenting strains of P . nalgiovense is suggested.

J Anim Sci, 1994 Dec, 72(12), 3238 - 45
Influence of crambe meal as a protein source on intake, site of digestion, ruminal fermentation, and microbial efficiency in beef steers fed grass hay; Caton JS et al.; Four ruminally and duodenally cannulated beef steers (558 +/- 37 kg) were arranged in a 4 x 4 Latin square to evaluate the influence of crambe meal as a protein source on intake, digestion, and microbial efficiency . Steers were offered chopped (10.2 cm) brome hay (6.2% CP) for ad libitum consumption and one of four supplements . Protein sources used were soybean and crambe meals (CM) . Protein sources were blended to provide four levels of supplemental CM protein (0, 33, 67, and 100%) . Protein supplements were fed to provide similar amounts of protein and energy . Amounts of supplements fed were 831, 885, 950, and 996 g of DM/steer daily for 0, 33, 67, and 100% CM treatments, respectively . Crambe meal represented 0, 2.00, 3.83, and 5.88% of the DM intake for respective treatments . Steers were allowed a 21-d adaptation to diets before each collection period . Supplements were offered at 0800 and forage at 0830 . Crambe meal had no influence (P > .10) on forage and total DM intake (grams/kilogram of BW) . Apparent total tract, ruminal, and postruminal digestion of OM, NDF, ADF, and N were unaffected (P > .10) by CM supplementation.(ABSTRACT TRUNCATED AT 250 WORDS)

Minerva Pediatr, 1994 Dec, 46(12), 569 - 74
{Hydrogen breath test in celiac disease: relationship to histological changes in jejunal mucosa}; Ansaldi-Balocco N et al.; Hydrogen concentration in expired breath depends on the fraction of ingested carbohydrates unabsorbed by the small intestinal mucosa which reach the large intestine and are fermented by the colonic flora . The aim of this study is to assess whether in coeliac children breath hydrogen excretion reflects the histological changes in the jejunal mucosa . Hydrogen breath test was performed on 40 children (15 males 25 females) divided into three groups . Group I (controls): 9 children with symptoms suggestive of coeliac disease who, after the appropriate workup, were found to suffer from other gastrointestinal disorders and had abnormal jejunal mucosa . Group II: 14 children who had been diagnosed as coeliacs according to the ESPGAN criteria, were kept on a gluten free diet for a minimum of 6 months and had a normal jejunal mucosa . Group III: 17 coeliac children who ate small quantities of gluten or were on a normal diet . At histology, 10 of them showed a total and 7 a partial atrophy of the jejunal mucosa . Breath hydrogen levels were measured both at baseline and after ingestion of a 2% sorbitol solution in water, at 30 minute intervals for four hours . The peak hydrogen level and the total surface area under the hydrogen excretion curve were also assessed . Coeliac children on a gluten containing diet excrete significantly more H2 than controls or coeliacs on a gluten free diet . Patients with more severe histological lesions had higher peak H2 levels and greater total excretion areas . In coeliac children, sorbitol breath H2 test represents a simple noninvasive technique to detect impaired jejunal function and it should have an important role as a screening test and in assessing dietary compliance.

Int J Parasitol, 1994 Dec, 24(8), 1089 - 97
Ancient biochemistries and the evolution of parasites; Bryant C; The characteristic respiratory metabolism of parasites consists of fermentation to carbon-rich, highly reduced volatile fatty acids which are excreted, and electron transport systems emphasising fumarate reductase and b-type cytochromes . The taxonomic groups that contribute major parasites (the heterogeneous protozoa and the helminths) have their evolutionary origins in environments from which oxygen was absent or present in very low concentrations . The Ediacarian period, about 700 million years ago, contains fossils of the appropriate grade of organisation to be contemporaneous with the ancestors of platyhelminths, nematodes and acanthocephalans . With the oxygen transition, carbon flow in the biosphere resulted in conservative, anoxic environments together with oxygen rich ones . The organisms of the former retained their emphasis on anaerobic energy generation, while cytochrome systems were as much concerned with oxygen detoxification as energy generation . Metabolic pathways in the modern parasitic groups are echoes of such ancient biochemistries.

Drug Saf, 1994 Dec, 11(6), 432 - 44
A risk-benefit appraisal of acarbose in the management of non-insulin-dependent diabetes mellitus; Santeusanio F et al.; Acarbose is an alpha-glucosidase inhibitor proposed for the treatment of diabetic patients . It acts by competitively inhibiting the alpha-glucosidases in the intestinal brush border . The principal action of these enzymes is to convert nonabsorbable dietary starch and sucrose into absorbable monosaccharides (e.g . glucose) . Enzyme inhibitors delay this conversion, slowing the formation and consequently the absorption of monosaccharides, and thus reducing the concentration of postprandial blood glucose . Both starch and sucrose are influenced, whereas lactose and glucose are not . Many studies in experimental animals, healthy volunteers and patients with non-insulin-dependent diabetes mellitus (NIDDM) have shown that acarbose decreases postprandial blood glucose, with a lesser reduction of fasting blood glucose, plasma triglycerides and postprandial insulin levels . In long term studies in NIDDM patients, acarbose significantly reduced glycosylated haemoglobin levels . Acarbose is only minimally absorbed from the gut and no systemic adverse effects have been demonstrated after long term administration . The drug allows undigested carbohydrates to pass into the large bowel where they are fermented causing flatulence, bloating and diarrhoea . These symptoms, which occur in approximately 30 to 60% of patients, tend to decrease with time and seem to be dose-dependent . They are minimised by starting therapy with low doses (such as 50mg 3 times daily) which may be effective in many patients . An increase in serum hepatic transaminases observed in earlier studies in the US, where doses of acarbose up to 900mg daily were used, has been not reported with the lower doses of the drug actually recommended {150 to 300mg (up to 600mg) daily} . In conclusion, acarbose may be useful in patients with NIDDM when diet alone is no longer able to maintain satisfactory blood glucose control . Furthermore, it may be a valid alternative to sulphonylurea or biguanide therapy when these drugs are contraindicated and insulin administration may be delayed . Acarbose seems also to be a useful adjunct to hypoglycaemic oral agents but its precise role in this field has not been fully clarified.

Yeast, 1994 Dec, 10(12), 1569 - 80
Increase in copy number of an integrated vector during continuous culture of Hansenula polymorpha expressing functional human haemoglobin; Gilbert SC et al.; Recombinant human haemoglobin A (rHbA) was produced by a leucine-requiring strain of Hansenula polymorpha which had been transformed with an integration vector containing the Saccharomyces cerevisiae LEU2 gene and cDNAs for the expression of alpha and beta globin each driven by the H . polymorpha MOX promoter . After 40 generations in a chemostat it was found that the integrated vector had become amplified in the host strain . In some cases this led to an increase in LEU2 gene dosage, but a loss of globin expression cassettes . In other cases the globin gene dosage also increased . These changes coincided with an increase in rHbA production in the culture, which was reversed when the dilution rate was increased . Isolates from a chemostat culture producing elevated levels of rHbA were grown in fed-batch fermentations, resulting in higher productivities than when inoculated with the parent strain . The rHbA produced was purified and characterized . Oxygen binding studies and electrospray mass spectrometry showed that the rHbA had been processed and assembled correctly, and behaved as a fully functional co-operative tetramer.

Yeast, 1994 Dec, 10(12), 1543 - 52
Genome renewal: a new phenomenon revealed from a genetic study of 43 strains of Saccharomyces cerevisiae derived from natural fermentation of grape musts; Mortimer RK et al.; We have analyzed by genetic means 43 strains of Saccharomyces that had been isolated from fermenting grape musts in Italy . Twenty eight of these strains were isolated from 28 cellars in the Region of Emilia Romagna . The other 15 strains came from 5 fermentations at four cellars near the city of Arpino, which is located south and east of Rome . We found that 20 of the 28 strains from Emilia Romagna were heterozygous at from one to seven loci . The balance were, within the limits of our detection, completely homozygous . All these strains appeared to be diploid and most were homozygous for the homothallism gene (HO/HO) . Spore viability varied greatly between the different strains and showed an inverse relation with the degree of heterozygosity . Several of the strains, and in particular those from Arpino, yielded asci that came from genetically different cells . These different cells could be interpreted to have arisen from a heterozygote that had sporulated and, because of the HO gene, yielded homozygous diploid spore clones . We propose that natural wine yeast strains can undergo such changes and thereby change a multiple heterozygote into completely homozygous diploids, some of which may replace the original heterozygous diploid . We call this process 'genome renewal'.

Plant Foods Hum Nutr, 1994 Dec, 46(4), 331 - 4
Tannins in utilization of sorghum grains in Burkina Faso; Sereme A et al.; The study of thirty sorghum varieties used for food in Burkina Faso showed a relationship between tannin level and utilization of sorghum grain . High tannin level varieties (more than 0.2%) are generally used for local alcoholic drink, instead low tannin level varieties (under 0.2%) are used for cooking and for non fermented drinks.

Can J Microbiol, 1994 Dec, 40(12), 1051 - 6
Influence of some selected ions on system water activity and on ethanol vapour pressure and its inhibitory action on Saccharomyces cerevisiae; Guerzoni ME et al.; The individual and interactive effects of some ionic species on the ethanol vapour pressure in equilibrium with the system, the water activity, and the fermentative performance of Saccharomyces cerevisiae were investigated . The concentrations of the ions Ca2+, Mg2+, and NH4+ were modulated according to a central composite design, within a range of values that can be individually considered optimal for S . cerevisiae . Although the temperature and ethanol and glucose concentrations were kept constant, the initial water activity and ethanol vapour pressure of the systems were remarkably affected by the interactions between the three ions studied . The data concerning the fermentative activity emphasize the role of the physical state of ethanol . In fact, when the ethanol concentration was kept constant, the highest fermentative performances of yeast were obtained when the ethanol vapour pressure, depending particularly on the Ca2+ and Mg2+ interaction, was the lowest in the matrix of values considered.

Mol Cell Probes, 1994 Dec, 8(6), 497 - 511
DNA probes and PCR in diagnosis of mycoplasma infections; Razin S; Laboratory diagnosis of mycoplasma infections is hampered by the difficulty or total failure to cultivate the organisms in vitro, and by the frequently weak and poorly specific serological response of the host . DNA probes consisting of cloned ribosomal RNA genes, cDNA to mycoplasmal rRNA, synthetic 16S rRNA oligonucleotide sequences, or cloned mycoplasmal protein genes, have been developed and applied as diagnostic tools in a variety of human and animal mycoplasma infections . These included primary atypical pneumonia caused by Mycoplasma pneumoniae, urogenital infections associated with M . genitalium and Ureaplasma urealyticum, and infections with M . fermentans, M . penetrans or M . pirum--mycoplasmas recently incriminated as cofactors in AIDS . DNA probes were also designed to aid in diagnosis of mycoplasma diseases of farm and laboratory animals, and the hard-to-diagnose mycoplasma infections of cell cultures . Sensitivity of mycoplasma detection by the different probes ranged between 10(3) and 10(6) colony-forming units, a level which may not be sufficiently high for use in a clinical laboratory . The introduction of PCR has pushed aside the previously developed DNA probes, by providing faster and much more sensitive tests . The sensitive level of a PCR test can be as low as a single organism, enabling detection of mycoplasmas in patients treated with antibiotics and in asymptomatic patients . PCR becomes positive prior to serological response and is also effective in immunocompromised hosts . PCR was shown to be most valuable in detection and identification of the non-culturable plant and insect mycoplasma-like organisms (MLOs) . Nevertheless, false-negative PCR results are rather common due to inhibitors of the PCR reaction in the clinical specimen, while false-positive results may occur due to contamination of the reagents with target DNA . In conclusion, the PCR procedure is still too complex to be carried out in a routine diagnostic laboratory . PCR prepackaged quality-controlled diagnostic kits are now in the process of rapid development . Once these kits become available, and at a reasonable cost, PCR will certainly take its place as a major diagnostic tool in the routine diagnosis of mycoplasma infections.

J Dairy Sci, 1994 Dec, 77(12), 3666 - 75
Flows of nitrogen and amino acids in dairy cows fed diets containing supplemental feather meal and blood meal; Cunningham KD et al.; Four Holstein cows, fitted with ruminal and duodenal cannulas, were used to determine the effects of supplemental feather meal and blood meal on ruminal fermentation and flows of N and AA to the duodenum . The basal diet contained (DM basis) 9.9% chopped alfalfa hay, 39.7% corn silage, 34.7% cracked corn, 8.2% corn starch, 2.1% vitamins and minerals, 4.4% casein, and 1% urea . A combination of feather meal and blood meal (3:1 on an N basis) was used to replace 0, 33, 67, and 100% of the casein and urea in the basal diet in a Latin square design . Intakes of DM, OM, and N were similar for all diets . Flows of total N, NAN, individual AA, total AA, and total essential AA were unaltered as supplemental feather meal plus blood meal increased . Flows of microbial N tended to decrease, but flow of non-ammonia, nonmicrobial N increased as supplemental feather meal plus blood meal increased . Increased proportions of dietary feather plus blood meal decreased the proportions of Ile, Lys, Met, and Thr in duodenal digesta . Molar percentages of ruminal pH and VFA were unchanged, but concentrations of ruminal NH3 N decreased linearly as supplemental feather meal plus blood meal increased . For the diets fed in this study, inclusion of one-third of the supplemental protein from feather plus blood meal resulted in maximum flows of NAN and microbial N to the small intestine.

J Dairy Sci, 1994 Dec, 77(12), 3655 - 65
Effect of protein source on ruminal fermentation and passage of amino acids to the small intestine of lactating cows; Erasmus LJ et al.; Four lactating Holstein cows, fitted with T-type cannulas in the proximal duodenum, were used in a 4 x 4 Latin square design to determine the effect of protein supplement on production, ruminal digestion, and profile and the quantity of AA available for absorption . Supplemental protein sources were blood meal, corn gluten meal, blood meal plus corn gluten meal, and sunflower meal, which constituted 8, 10.5, 9.3, and 13% of dietary DM, respectively . The DMI and milk production were not influenced by treatment . Ruminal NH3 concentration increased with the sunflower meal diet, and molar percentage of propionate decreased with the blood meal diet . Duodenal flow of NAN was unaffected by protein source, but dietary N flow decreased, and bacterial N flow increased, when cows were fed the sunflower meal diet . Bacterial N flows were 46.0, 45.3, 46.4, and 65.8% of NAN for the respective diets . The AA profiles of isolated ruminal bacteria differed among dietary treatments but were not correlated with the respective supplementary protein sources . The essential AA profiles of duodenal digesta and duodenal flow of individual AA closely reflected AA differences in protein sources, suggesting that the composition of RUP profoundly affected the composition of protein entering the intestine when supplemental protein provided 35% of total CP intake.

Aliment Pharmacol Ther, 1994 Dec, 8(6), 563 - 77
Review article: practical management of the short bowel; Lennard-Jones JE; A shortened small intestine may end at a stoma or be anastomosed to the colon . Patients with a jejunostomy, but not those with a colon, lose large amounts of sodium . The intake and absorption of sodium can be increased by sipping a sodium-glucose solution; stomal loss can be reduced by restricting water or low-sodium drinks . If a stoma is situated less than 100 cm along the jejunum, a constant negative sodium balance may necessitate parenteral saline supplements . Gastric anti-secretory drugs or a somatostatin analogue reduce jejunostomy losses in such patients but do not restore a positive sodium balance . Loperamide or codeine phosphate benefit some patients . Magnesium deficiency can usually be corrected by oral magnesium oxide supplements . An elemental or hydrolysed diet is not beneficial . Patients with a jejunostomy can maintain a normal diet without fat reduction . When the colon is present, unabsorbed carbohydrate is fermented to absorbable short chain fatty acids . Unabsorbed long chain fatty acids and bile salts cause watery diarrhoea and increased colonic oxalate absorption with hyperoxaluria . Such patients benefit from a high carbohydrate, low-fat and low-oxalate diet . Parenteral nutrition is needed only by the few patients unable to maintain health or avoid socially disabling diarrhoea despite these measures.

J Pharm Biomed Anal, 1994 Dec, 12(12), 1483 - 8
Evaluation of tetracycline raw materials and finished products found on the Kenyan market; Muritu JW et al.; Contents of tetracycline, its degradation products (epitetracycline, epianhydrotetracycline, anhydrotetracycline) and a fermentation impurity (2-acetyl-2-decarboxamidotetracycline) were determined in four raw materials, 12 batches of six ointment products, four eye ointment products and nine batches of five capsule products, all sampled from the Kenyan market . The analytical method was liquid chromatography on a column packed with a poly(styrenedivinyl-benzene) material (8-microns PLRP-S 100 A) . All raw materials and finished products had tetracycline contents and impurity levels within the prescribed compendial limits.

Acta Med Port, 1994 Dec, 7 Suppl 1, S51 - 5
Interaction of the constituents of alcoholic beverages in the promotion of liver damage; Peneda J et al.; Little has been studied of the adverse effects of the exposure of the liver to the interaction of ethanol with its congeners and acetaldehyde, coexisting in the contents of alcoholic beverages . Twenty four male Wistar rats were divided into four groups . Two groups (SH/DA; SH/FA) were submitted to daily treatment with synthetic hydroalcoholic solutions containing ethanol, methanol, higher alcohols and acetaldehyde in the same proportions as those found in most common distilled and fermented alcoholic beverages; the third group (SH/EA) was treated with a hydroalcoholic solution of ethanol; the fourth group served as control and received an equivalent volume of an isocaloric solution of dextrose . All the animals were killed at the end of the 9th week of the experiment . The ratio between the liver weight and body weight was found to be lower in the treated animals than in the control group . The histology of the liver was altered in the three groups which were submitted to treatment with the hydroalcoholic solutions, with quantitative and qualitative differences between the groups . These results suggest that the hepatoxicity of ethanol in alcoholic beverages is enhanced by interaction with its congeners and acetaldehyde; they also suggest that alcoholic beverages are not equivalent in their potential to cause liver damage.

Ann N Y Acad Sci, 1994 Nov 30, 745, 222 - 31
Acid precipitation of mammalian cell fermentation broth; Lydersen BK et al.; The broth harvested from the "fermentation" of mammalian cells contains many contaminants produced by the cells, including nucleic acids, proteins, and complex polysaccharides, in addition to the product . These contaminants can foul filtration membranes, precipitate during storage or processing steps, and interfere with the performance of chromatographic separations . Acidification of hybridoma cell fermentation broth at the time of harvest from the fermenter has been investigated as a method of selectively precipitating the major contaminants from the soluble antibody product . Between pH values of 6.0 and 4.5, precipitation of the major contaminants is rapid and independent of the temperature (4-37 degrees C), with less than 10% of the antibody coprecipitating in 4 of 5 cases . Antibody activity and physical characteristics were found to be unaltered above a pH of 3.8 . Recovery of antibody at the stage of concentrated (50 x), diafiltered bulk was improved from 63% to 84% by using the acid precipitation step . An additional benefit is that retrovirus is effectively inactivated by incubation at a pH below 4.2.

Eur J Biochem, 1994 Nov 15, 226(1), 41 - 51
Location of the two genes encoding glutaconate coenzyme A-transferase at the beginning of the hydroxyglutarate operon in Acidaminococcus fermentans; Mack M et al.; Glutaconate coenzyme A-transferase (Gct) from Acidaminococcus fermentans consists of two subunits (GctA, 35725 Da and GctB, 29168 Da) . The N-termini sequences of both subunits were determined . DNA sequencing of a subgenomic fragment of A . fermentans revealed that the genes encoding glutaconate CoA-transferase (gctAB) are located upstream of a gene cluster formed by gcdA, hgdC, hgdA and hgdB in this order . Further upstream of gctA, a DNA sequence was detected showing significant similarities to sigma 70-type promoters from Escherichia coli . Primer-extension analysis revealed that this specific DNA sequence was indeed the location of transcription initiation in A . fermentans . The entire gene cluster, 7.3 kb in length, comprising gctAB, gcdA and hgdCAB, has tentatively been named the hydroxyglutarate operon, since the enzymes encoded by these genes are involved in the conversion of (R)-2-hydroxyglutarate to crotonyl-CoA in the pathway of glutamate fermentation by A . fermentans . The genes gctAB were expressed together in E . coli . Cell-free extracts of a transformant E . coli strain contained glutaconate CoA-transferase at a specific activity of up to 30 U/mg protein . The recombinant enzyme was purified to homogeneity with a specific activity of 130 U/mg protein by ammonium sulfate fractionation and crystallisation . The amino acid residue directly involved in catalysis was tentatively identified as E54 of the small subunit of the enzyme (GctB).

Comp Biochem Physiol A Physiol, 1994 Nov, 109(3), 649 - 53
The gastrointestinal tract of the rock hyrax (Procavia habessinica) . 1 . Morphology and motility patterns of the tract; Bjornhag G et al.; The stomach of the rock hyrax (Procavia habessinica) is divided into a non glandular part with very slow movements, and a glandular part which rapidly mix the digesta . The large intestine has two fermentation chambers, the caecum, which rapidly mixes the digesta, and the colonic sac, which efficiently, but slowly, mixes digesta . Between these chambers runs the connecting colon . No retrograde transport is observed in any part of the large intestine.

J Appl Bacteriol, 1994 Nov, 77(5), 541 - 8
Degradation and utilization of forage hemicellulose by rumen bacteria, singly in coculture or added sequentially; Fondevila M et al.; Procedures for sequential addition experiments were developed to study the mechanisms involved in the synergistic and inhibitory interactions observed in forage hemicellulose digestion by rumen bacterial cocultures . One organism was allowed to ferment a forage substrate, the culture tube was sterilized and then inoculated with a second organism . No differences were found in the extent of degradation or utilization between fermentations sterilized by oxidation or heat, and based on ease of handling, heat was used in all subsequent experiments . Studies were conducted with Fibrobacter succinogenes A3c, Ruminococcus flavefaciens B34b and Prevotella ruminicola H2b, singly and in all possible combinations . Results from the sequential addition studies substantiated earlier suggestions that the increase observed in hemicellulose utilization results from initial solubilization of the hemicellulose from the forage by the non-utilizer and subsequent utilization of subsequent utilization of this solubilized polysaccharide by the utilizing, but non-degrading organism.

J Antibiot (Tokyo), 1994 Nov, 47(11), 1226 - 33
Isolation and characterization of new 18-membered macrolides FD-891 and FD-892; Seki-Asano M et al.; New 18-membered macrolides FD-891 and FD-892 were discovered from the fermentation broth of Streptomyces graminofaciens A-8890 isolated from a soil sample collected at Yamanashi prefecture Japan . They induce morphological changes of HL-60 cells at low concentration below IC50s and have cytocidal activity against in vitro tumor cell lines . FD-891 showed 2 approximately 7 times stronger activity than doxorubicin whereas FD-892 was 20 approximately 100 fold weaker than FD-891 and doxorubicin.

Appl Environ Microbiol, 1994 Nov, 60(11), 3952 - 8
Acetate metabolism by Escherichia coli in high-cell-density fermentation; Kleman GL et al.; Little is known about the cellular physiology of Escherichia coli at high cell densities (e.g., greater than 50 g {dry cell weight} per liter), particularly in relation to the cellular response to different growth conditions . E . coli W3100 cultures were grown under identical physical and nutritional conditions, by using a computer-controlled fermentation system which maintains the glucose concentration at 0.5 g/liter, to high cell densities at pH values of 6.0, 6.5, 7.0, and 7.5 . The data suggest a relationship between the pH of the environment and the amount of acetate excreted by the organism during growth . At pH values of 6.0 and 6.5, the acetate reached a concentration of 6 g/liter, whereas at pH 7.5, the acetate reached a concentration of 12 g/liter . Furthermore, at pH values of 6.0 to 7.0, the E . coli culture undergoes a dramatic metabolic switch in which oxygen and glucose consumption and CO2 evolution all temporarily decreased by 50 to 80%, with a concomitant initiation of acetate utilization . After a 30-min pause in which approximately 50% of the available acetate is consumed, the culture recovers and resumes consuming glucose and oxygen and producing acetate and CO2 at preswitch levels . During the switch period, the specific activity of isocitrate lyase typically increases approximately fourfold.

FEMS Microbiol Lett, 1994 Nov 1, 123(3), 255 - 60
Membrane lipids of Mycoplasma fermentans; Salman M et al.; Membranes of Mycoplasma fermentans, incognitus strain, were isolated by a combination of osmotic lysis and sonication . Analysis of membrane lipids revealed, in addition to free and esterified cholesterol, six major polar lipids dominated by a de novo synthesized compound (compound X), which accounts for 64% of the total lipid phosphorus . Compound X was labeled by palmitate, but not by oleate . Mass spectrometry and gas liquid chromatography analyses of compound X revealed two molecular species with molecular masses of 1048 and 1076 representing, a dipalmitoyl- and a stearoyl-palmitoyl-glycerodiphosphatidylcholine . Compound X has the ability to stimulate human monocytes to secret TNF alpha and to enhance the fusion of small unilamellar vesicles with MOLT-3 lymphocytes.

J Cell Biol, 1994 Nov, 127(3), 751 - 62
Saccharomyces cerevisiae contains four fatty acid activation (FAA) genes: an assessment of their role in regulating protein N-myristoylation and cellular lipid metabolism; Johnson DR et al.; Saccharomyces cerevisiae has been used as a model for studying the regulation of protein N-myristoylation . MyristoylCoA:protein N-myristoyl-transferase (Nmt1p), is essential for vegetative growth and uses myristoylCoA as its substrate . MyristoylCoA is produced by the fatty acid synthetase (Fas) complex and by cellular acylCoA synthetases . We have recently isolated three unlinked Fatty Acid Activation (FAA) genes encoding long chain acylCoA synthetases and have now recovered a fourth by genetic complementation . When Fas is active and NMT1 cells are grown on media containing a fermentable carbon source, none of the FAA genes is required for vegetative growth . When Fas is inactivated by a specific inhibitor (cerulenin), NMT1 cells are not viable unless the media is supplemented with long chain fatty acids . Supplementation of cellular myristoylCoA pools through activation of imported myristate (C14:0) is predominantly a function of Faa1p, although Faa4p contributes to this process . Cells with nmt181p need larger pools of myristoylCoA because of the mutant enzyme's reduced affinity for this substrate . Faa1p and Faa4p are required for maintaining the viability of nmt1-181 strains even when Fas is active . Overexpression of Faa2p can rescue nmt1-181 cells due to activation of an endogenous pool of C14:0 . This pool appears to be derived in part from membrane phospholipids since overexpression of Plb1p, a nonessential lysophospholipase/phospholipase B, suppresses the temperature-sensitive growth arrest and C14:0 auxotrophy produced by nmt1-181 . None of the four known FAAs is exclusively responsible for targeting imported fatty acids to peroxisomal beta-oxidation pathways . Introduction of a peroxisomal assembly mutation, pas1 delta, into isogenic NMT1 and nmt1-181 strains with wild type FAA alleles revealed that when Fas is inhibited, peroxisomes contribute to myristoylCoA pools used by Nmt1p . When Fas is active, a fraction of cellular myristoylCoA is targeted to peroxisomes . A NMT1 strain with deletions of all four FAAs is still viable at 30 degrees C on media containing myristate, palmitate, or oleate as the sole carbon source--indicating that S . cerevisiae contains at least one other FAA which directs fatty acids to beta-oxidation pathways.

Antimicrob Agents Chemother, 1994 Nov, 38(11), 2651 - 4
In vitro antimycoplasmal activities of rufloxacin and its metabolite MF 922; Furneri PM et al.; The in vitro activities of rufloxacin and its metabolite, MF 922, were compared with those of ofloxacin, ciprofloxacin, erythromycin, and minocycline against Mycoplasma pneumoniae, Mycoplasma hominis, Mycoplasma fermentans, and Ureaplasma urealyticum . Rufloxacin, MF 922, and ciprofloxacin shared similar activities against all mycoplasmas tested . (MICs for 90% of isolates tested {MIC90s}, 0.5 to 4 micrograms/ml . Ofloxacin had the lowest MIC90s for U . urealyticum, M . fermentans, and M . hominis (MIC90s, 0.25 to 1 micrograms/ml) and erythromycin had the lowest MIC90 for M . pneumoniae (MIC90, 0.004 micrograms/ml).

Scand J Gastroenterol, 1994 Nov, 29(11), 1009 - 16
Absorption of short-chain fatty acids from the in-situ-perfused caecum and colon of the guinea pig; Oltmer S et al.; BACKGROUND: Short-chain fatty acids (SCFA) originate from microbial fermentation of carbohydrates in the hindgut . Mechanisms involved in SCFA absorption are not fully understood . METHODS: The caecum and proximal and distal colon of the guinea pig were perfused in situ . RESULTS: SCFA absorption per gram mucosal dry weight was highest in the proximal colon and lowest in the caecum . Owing to the large surface, quantitatively SCFA absorption was highest from the caecum . In the distal colon clearance of SCFA increased with chain length (Ac < Pr < Bu); in the caecum and proximal colon only a comparatively small or no such influence was observed . Inhibition of the proton antiport systems in the apical membrane and inhibition of the carbonic anhydrase activity diminished SCFA absorption . The diffusive and carrier components of absorption were calculated for propionate at increasing propionate concentrations . CONCLUSIONS: Marked segmental differences in SCFA absorption are apparent in the large intestine of the guinea pig.

Zh Obshch Biol, 1994 Nov-Dec, 55(6), 737 - 48
{The reciprocal training of Drosophila individuals in a group situation by the trial-and-error method}; Kamyshev NG et al.; In the group situation, fruit flies try to avoid conflicts in which they kick each others . At first they attempt to escape from each other thus increasing run frequency as compared with control solitary individuals, but shortly terminate runs in order to prevent collisions . Motoric activity and conflict frequency during encounters are high in such situations . From the very beginning, probability of transition from activity to direct contact is higher than that from rest to contact or from preening to contact . Therefore, during the first 5 minutes a fly learns to increase interval between runs using the trial-and-error method . Besides abrupt decreasing of number of collisions and activity of flies in group as compared with control, operant training leads to formation of passive aggregations, because closely situated flies avoid to display activity . A new behavior reaction is developed, as well, namely immobile fly initiate preventive touches by legs . Such training is adaptive because in the natural aggregations of flies on fermented fruits it increases aggressive activity decreasing thus raising efficiency of feeding on a common substrate.

Eur J Nucl Med, 1994 Nov, 21(11), 1231 - 3
Experimental biodistribution studies of 99mTc-recombinant human serum albumin (rHSA): a new generation of radiopharmaceutical; Perkins AC et al.; Recombinant human serum albumin (rHSA) produced by cultured fermentation has been prepared in the form of microcapsules nominally 3-5 microns in diameter and radiolabelled with technetium-99m following reduction with stannous chloride . Radiochemical purity was assessed by chromatography on instant thin-layer chromatography and found to be greater than 90% . No evidence of aggregation was seen by microscopic examination . Imaging biodistribution studies in New Zealand white rabbits demonstrated targeting to the liver or lung, respectively, depending upon the size and surfactant properties of the microcapsules . This communication is the first to show scintigraphic studies using 99mTc-labelled rHSA with the potential for lung, liver and cardiovascular imaging and demonstrates that recombinant DNA technology offers an important new source of materials suitable for use as radiopharmaceuticals without the need for pooled human blood products.

J Clin Microbiol, 1994 Nov, 32(11), 2769 - 74
Comparison of six typing methods for Actinobacillus actinomycetemcomitans; van Steenbergen TJ et al.; Actinobacillus actinomycetemcomitans is an important pathogen in the etiology of severe periodontitis . For epidemiological studies on the prevalence of certain pathogenic clones and transmission of this bacterium, adequate typing methods are necessary . The purpose of this study was to compare six different typing methods for A . actinomycetemcomitans . Five reference strains and 27 fresh clinical isolates from periodontitis patients were used . Serotyping showed 12 serotype a strains, 13 type b strains, 6 type c strains, and 1 nontypeable strain . Biotyping on the basis of the fermentation of mannose, mannitol, and xylose resulted in six biotypes . Antibiogram typing was evaluated by measuring the inhibition zones of seven antibiotics in agar diffusion tests . With this method eight main types which could be further differentiated into 15 subtypes were found . Sodium dodecyl sulfate-polyacrylamide gel electrophoresis patterns of outer membrane proteins were similar among all isolates tested . Restriction endonuclease analysis (REA) of whole chromosomal DNA resulted in five main types . These five main types were further differentiated into 24 subtypes on the basis of DNA fragment differences in the high-molecular-weight region . Hybridization of DNA fragments with ribosomal DNA (ribotyping) resulted in 22 to 24 different types, depending on the restriction endonuclease used . Ribotype patterns were easy to interpret and provided an univocal distinction between different strains compared with REA results . When applied to epidemiologically related isolates, all methods were able to discriminate two clonal types among five isolates from five children from one family . We conclude that serotyping, biotyping, and outer membrane patterns were reproducible but had a low discriminatory potential . REA and ribotyping were reproducible and gave the highest number of distinct types . When the DNA typing methodis were compared, all strains tested could be distinguished . These findings confirm the heterogeneity found within the species A . actinomycetemcomitans.

Nutr Hosp, 1994 Nov-Dec, 9(6), 355 - 63
{Enteral nutrition and fiber in intensive care}; Ordonez J et al.; As in other fields of Medicine and Nutrition, the study of Alimentary Fiber or Dietary Fiber is becoming particularly intensive: its use in Intensive Care patients has however scarcely been explored . For comparison, its utility in diarrhea is assumed as main indication . This has not however been demonstrated . The scant research studies have not proven that diarrhea is controlled, particularly taking account of its complexity and multifactorial etiology . However, its utility has been shown in glucose-intolerance which is so common in Intensive Care Units, as in Diabetes . Current research is examining its bacterial fermentation products, short-chain fat acids (acetate, propionate and butyrate) and their importance as an energy source both of the intestinal and systemic mucosa . Short-chain fat acids are the preferred fuel of the colonic mucosa and an additional calorie contribution ought not to be ignored.

Mol Biol Evol, 1994 Nov, 11(6), 921 - 8
Molecular adaptation of a leaf-eating bird: stomach lysozyme of the hoatzin; Kornegay JR et al.; This report describes a lysozyme expressed at high levels in the stomach of the hoatzin, the only known foregut-fermenting bird . Evolutionary comparison places it among the calcium-binding lysozymes rather than among the conventional types . Conventional lysozymes were recruited as digestive enzymes twice in the evolution of mammalian foregut fermenters, and these independently recruited lysozymes share convergent structural changes attributed to selective pressures in the stomach . Biochemical convergence and parallel amino acid replacements are observed in the hoatzin stomach lysozyme even though it has a different genetic origin from the mammalian examples and has undergone more than 300 million years of independent evolution.

J Dairy Sci, 1994 Nov, 77(11), 3432 - 40
Effects of cobalt on in vitro fiber digestion of forages and by-products containing fiber; Hussein HS et al.; Cobalt glucoheptonate as a source of Co to enhance ruminal fiber digestion was evaluated in two in vitro digestibility experiments . In Experiment 1, Co supplementation (0, 5, and 10 ppm) of five substrates (leaf and stem fractions of alfalfa and orchardgrass hays and ground corn) was evaluated under two dietary conditions (ruminal fluid taken from steers fed alfalfa hay or a high concentrate diet) for 24 or 48 h of fermentation in a 3 x 5 x 2 x 2 factorial arrangement . In Experiment 2, four concentrations of Co (0, 10, 20, and 30 ppm) were added to five substrates (alfalfa hay, orchardgrass hay, corn cobs, recycled newsprint treated with HCl, and cellulose casings) and were incubated with ruminal fluid from steers fed alfalfa hay for 24 or 48 h of fermentation in a 4 x 5 x 2 factorial arrangement . No interactions among treatments were observed for digestibilities of DM, OM, or NDF in both experiments or for VFA concentrations in Experiment 1 . Supplementation with Co did not increase digestibilities of DM, OM, or NDF in either experiment or concentrations of VFA in Experiment 1 . In Experiment 1, in vitro digestibilities of DM, OM, and NDF were higher for inoculum from steers fed alfalfa versus concentrate . In Experiment 2, digestibilities of DM, OM, and NDF were highest for alfalfa hay and lowest for recycled newsprint treated with HCl . Cobalt concentrations that were above minimum requirements did not improve digestion of DM, OM, or fiber.

J Dairy Sci, 1994 Nov, 77(11), 3338 - 46
Effects of temperature and oxygen tension on growth of Escherichia coli in milk; Goldberg JJ et al.; An in vitro system was developed to mimic conditions within normal and mastitic mammary glands . The system consisted of a modified batch fermenter that allowed for manipulation of temperature, oxygen tension, and pH . Experiments in tryptose-soy broth and UHT-treated milk were conducted to evaluate growth characteristics of Escherichia coli P4 as physical conditions were manipulated . The effect of bacterial growth on oxygen tension and pH were also evaluated . Growth of E . coli was inhibited as temperature was increased from 37 to 41 degrees C and as oxygen tension was decreased from microaerophilic to anaerobic levels . At bacterial populations > 6 log10 cfu/ml, microaerophilic cultures became anaerobic . The pH followed a similar trend; however, after a significant decrease in pH, mean bacterial populations were 7.1 log10 cfu/ml in tryptosesoy broth and 8.2 log10 cfu/ml in UHT-treated milk . This dynamic model demonstrated potential use in evaluation of growth characteristics of mammary gland pathogens in the lactating mammary gland.

Microbiology, 1994 Nov, 140 ( Pt 11), 3031 - 8
Induction of major heat-shock proteins of Saccharomyces cerevisiae, including plasma membrane Hsp30, by ethanol levels above a critical threshold; Piper PW et al.; Many of the changes induced in yeast by sublethal yet stressful amounts of ethanol are the same as those resulting from sublethal heat stress . They include an inhibition of fermentation, increased induction of petites and stimulation of plasma membrane ATPase activity . Ethanol, at concentrations (4-10%, v/v) that affect growth and fermentation rates, is also a potent inducer of heat-shock proteins including those members of the Hsp70 protein family induced by heat shock . This induction occurs above a threshold level of about 4% ethanol, although different heat-shock proteins and heat-shock gene promoters are optimally induced at different higher ethanol levels . In addition ethanol (6-8%) causes the same two major changes to integral plasma-membrane protein composition that result from a sublethal heat stress, reduction in levels of the plasma membrane ATPase protein and acquisition of the plasma membrane heat-shock protein Hsp30.

Appl Microbiol Biotechnol, 1994 Nov, 42(2-3), 340 - 5
Growth rate influences MF alpha 1 promoter activity in MAT alpha Saccharomyces cerevisiae; Kirk N et al.; The signal sequences of the MF alpha 1 prepro alpha-factor gene are frequently used to direct secretion of heterologous proteins from Saccharomyces cerevisiae . They are often employed together with the MF alpha 1 promoter in secretion vectors, such that this promoter directs the transcription of many heterologous gene cassettes in yeast . Most of the existing literature indicates that the MF alpha 1 promoter is constitutive in MAT alpha cells, although some data suggests that it may be more active in respiratory or late logarithmic fermentative cultures . To identify whether there is a growth rate or medium control over MF alpha 1 promoter activity a strain was constructed with an integrated MF alpha 1 promoter-beta-galactosidase (lacZ) reporter gene fusion . Intracellular beta-galactosidase of this strain during batch culture on glucose, raffinose and acetate showed that MF alpha 1 promoter activity was higher during respiratory growth on acetate as compared to more rapid fermentative growth on glucose or raffinose, a result that might indicate this activity being inversely related to growth rate . Chemostat culture confirmed that growth rate does indeed influence MF alpha 1 promoter activity in glucose-grown cells, the activity of this promoter increasing 2- to 2.5-fold as dilution (growth) rates were reduced from maximal values to 0.2 h-1, but then decreasing with the further decreases in dilution rate needed for fully respiratory growth . Thus a promoter generally thought to be constitutive in MAT alpha cells is nevertheless subject to a complex growth rate control.

Biotechnol Prog, 1994 Nov-Dec, 10(6), 644 - 7
Effect of modulated glucose uptake on high-level recombinant protein production in a dense Escherichia coli culture; Chou CH et al.; Methyl alpha-glucoside (alpha-MG) is a metabolically inert glucose analog sharing the same phosphotransferase system with glucose . The potential of using this compound, which acts as a nontoxic competitive inhibitor, to modulate glucose uptake and subsequently reduce the acetate accumulation rate was investigated . In a complex medium, no significant effect on the growth rate was observed when the alpha-MG to glucose ratio was low . The effect of alpha-MG supplementation on the production of a model recombinant protein, CadA-beta-galactosidase, under the regulation of a pH-inducible promoter in a batch culture was also examined . It was observed that the amount of acetate accumulation was drastically reduced in the presence of alpha-MG . More importantly, recombinant protein productivity was significantly improved . A very high volumetric productivity of approximately 1.6 g/L recombinant protein in a dense culture with an OD600 of 35 was obtained in a simple batch fermentation . Even at this high cell density, the specific protein productivity was maintained at a high level and was estimated to account for about 40% of the total cellular protein.

Biotechnol Prog, 1994 Nov-Dec, 10(6), 621 - 9
Temperature and growth rate effects on the hok/sok killer locus for enhanced plasmid stability; Wu K et al.; The hok/sok locus, isolated from the multiple-resistance plasmid R1 of Escherichia coli, is very efficient at ensuring the stable maintenance of plasmids in Gram-negative systems by killing plasmid-free cells as they arise . To investigate independently the influence of temperature and growth rate on the effectiveness of hok/sok, continuous fermentations have been conducted with the pUC-based, IPTG-induced, beta-galactosidase expression vector pTKW106 . At fixed temperature (37 degrees C), decreasing the dilution rate decreased plasmid stability, and at a fixed, low dilution rate (D = 0.15/h), decreasing the temperature resulted in an increase in plasmid stability . These trends are explained by the specific beta-galactosidase activity of each continuous fermentation: higher, specific, recombinant protein expression led to decreased plasmid stability (due to either segregational or structural instability, as determined by plasmid DNA isolation) . A representative fed-batch medium produced more beta-galactosidase on a volumetric basis than M9C in the chemostat, and addition of the hok/sok locus increased segregational stability by 8-22-fold in continuous fermentations that lacked antibiotic selection pressure and in which beta-galactosidase was constantly expressed a 12% of total cell protein for 60 h (43-47 generations).

J Ind Microbiol, 1994 Nov, 13(6), 372 - 81
Genetic modification of an echinocandin B-producing strain of Aspergillus nidulans to produce mutants blocked in sterigmatocystin biosynthesis; Hodges RL et al.; The production of echinocandin B (ECB), a lipopolypeptide used for chemical manufacture of the anti-Candida agent Cilofungin, was accomplished by fermentation using a strain of Aspergillus nidulans . In addition to ECB, this fermentation also produces a significant amount of sterigmatocystin (ST), a potent carcinogen structurally related to the aflatoxins . Mutants blocked in the ST biosynthetic pathway were created by genetic modification of the polyploid production strain C747 . The following steps were involved: (i) reduction of the genotype to haploid by treatment with the spindle fiber poison methyl 1-(butylcarbamoyl)-2-benzimidazole carbamate (MBC), using colony morphology, conidia size, and the ability to obtain 5-fluoro-orotic acid (5-FOA)-resistant mutants as criteria for ploidy; (ii) mutagenesis of a haploid isolate using UV irradiation; and (iii) screening of mutants for inability to produce ST by thin layer chromatography . Six mutants blocked in ST production were isolated . All six remained capable of producing ECB equivalent in quantity to the haploid strain C747-GR14 . One of the mutants was shown to be the result of a chromosomal translocation.

J Ind Microbiol, 1994 Nov, 13(6), 356 - 60
Large scale production and semi-purification of kedarcidin in a 1000-L fermentor; Lam KS et al.; Actinomycete strain ATCC 53650 was grown in a 1000-L fermentor containing 680 L of medium and the production of kedarcidin was monitored by HPLC . The titers of kedarcidin in the fermentor cultures were 0.49-0.53 mg ml-1 . A quick and efficient purification method involving the use of anion exchange resin DE23 (batch adsorption-desorption) and an ultrafiltration system yielded high recovery (65% yield) of kedarcidin from the fermentor culture . Over 200 grams of lyophilized kedarcidin of 70% purity was recovered from each of two 1000-L fermentor cultures using this process.

J Chem Technol Biotechnol, 1994 Nov, 61(3), 247 - 50
Synergistic extraction of penicillin G with aliphatic alcohols and butyl acetate; Yang ZF et al.; A solvent mixture of 1-hexanol and butyl acetate has been successfully used for the extraction of penicillin G . This solvent mixture may not only synergistically and effectively extract penicillin G, but also inhibit emulsion formation during the extraction of penicillin G from the filtrate of the fermentation broth . The equilibrium constants of the extraction, the molar ratios of 1-hexanol and penicillin G in the extracted species and the synergistic extraction of penicillin G have been studied by chemical analysis and by monitoring the absorbency shift in the FT-IR spectra of the functional groups in the solvents.

Biotechnology (N Y), 1994 Nov, 12(11), 1113 - 7
Large scale, in situ isolation of periplasmic IGF-I from E . coli; Hart RA et al.; Human insulin-like growth factor I (IGF-I) accumulates in both folded and aggregated forms in the fermentation medium and cellular periplasmic space when expressed in E . coli with an endogenous secretory signal sequence . Due to its heterogeneity in form and location, low yield of IGF-I was obtained using a typical refractile body recovery strategy . To enhance recovery yield, a new procedure was developed to solubilize and extract IGF-I from cells while in fermentation broth . This method, called in situ solubilization, involves addition of chaotrope and reductant to alkaline fermentation broth and provides recovery of about 90% of all IGF-I in an isolated supernatant . To further enhance recovery, a new aqueous two-phase extraction procedure was developed which partitions soluble non-native IGF-I and biomass solids into separate liquid phases . This two-phase extraction procedure involves addition of polymer and salt to the solubilization mixture and provides about 90% recovery of solubilized IGF-I in the light phase . The performance of the solubilization and aqueous extraction procedures is reproducible at scales ranging from 10 to 1000 liters and provides a 70% cumulative recovery yield of IGF-I in the isolated light phase . The procedure provides significant initial IGF-I purification since most host proteins remain cell associated during solubilization and are enriched in heavy phase . ELISA analysis for E . coli proteins indicates that 97% of the protein in the light phase is IGF-I . Together, the techniques of in situ solubilization and aqueous two-phase extraction provide a new, high yield approach for isolating recombinant protein which is accumulated in more than one form during fermentation.

Biotechnology (N Y), 1994 Nov, 12(11), 1107 - 10
Construction and characterization of a set of E . coli strains deficient in all known loci affecting the proteolytic stability of secreted recombinant proteins; Meerman HJ et al.; Even though secretion offers numerous advantages for the production of proteins in Escherichia coli, the expression of many heterologous proteins is severely limited by degradation in the periplasmic space . We found that mutations in rpoH, the RNA polymerase sigma factor responsible for heat shock protein synthesis, affect the stability of heterologous secreted proteins . A particularly dramatic increase in expression was further observed in rpoH degP double mutants . To minimize proteolytic degradation, we constructed a family of 25 isogenic strains deficient in all known cell envelope proteases (DegP, Protease III, Tsp(Prc), and OmpT), as well as the rpoH15 mutant allele, and characterized their growth in both shake flasks and fermentors . The availability of this set of strains permits the selection of a suitable host based on the optimal combination between the optimum reduction in protease activity and acceptable growth properties.

J Anim Sci, 1994 Nov, 72(11), 2992 - 3003
Ruminal microbiology, biotechnology, and ruminant nutrition: progress and problems; Wallace RJ; Present methods for manipulating ruminal fermentation that involve microbial biotechnology include dietary ionophores, antibiotics, and microbial feed additives . Developments in recombinant DNA technology mean that future methods will have a much wider scope . It has been suggested that genetically engineered ruminal microorganisms will be used in future to improve ruminal fermentation . Several technical objectives must be achieved before that will be possible . First, methods for inserting foreign or modified genes into ruminal microorganisms and ensuring their efficient expression must be developed . Broad host range plasmids and transposons have been used successfully to introduce new DNA into ruminal bacteria, as have shuttle vectors constructed as chimeras of plasmids from ruminal species and Escherichia coli . Although so far only antibiotic resistance markers have been transferred, the prospects for introducing other genes into selected ruminal bacteria are excellent . Second, the expression of the gene product(s) should be known to be nutritionally useful in vivo . A few examples of this type of benefit have been demonstrated, and many more proposed, including polysaccharidases for improving fiber digestion, methods for improving the amino acid composition of ruminal bacteria, and breakdown of plant toxins . Third, the difficulty that has been examined least, yet may prove most difficult to overcome, is that mechanisms have to be found for introducing and maintaining the new strain in the mixed ruminal population . Factors governing the survival of new strains in vivo are ill-understood, and attempts to select in favor of added new organisms have so far been unsuccessful . Because of the last obstacle, it may be advantageous, at least in the short term, to use nonruminal organisms, such as Saccharomyces cerevisiae, rather than indigenous ruminal species as a vehicle for implementing the benefits of recombinant DNA technology to ruminal fermentation . Yeast is already in widespread use as a feed additive, so no enrichment is necessary; and its genetics are already well known . Alternatively, adding particular enzymes to the diet may achieve some of the objectives described above, with the advantage that the manipulation could be achieved without the release of a recombinant microorganism.

JPEN J Parenter Enteral Nutr, 1994 Nov-Dec, 18(6), 486 - 90
Reduction in diarrhea incidence by soluble fiber in patients receiving total or supplemental enteral nutrition; Homann HH et al.; BACKGROUND: Gastrointestinal side effects, particularly diarrhea, are still the main reasons for discontinuation of enteral nutrition . Although the causes of diarrhea are diverse, the enteral nutrition solution is frequently suspected of playing a leading role in causing diarrhea . METHODS: Our randomized, prospective, double-blind trial with 100 patients assessed the effects of feeding a standard diet (Nutrodrip Standard) vs the same diet supplemented with 20 g of soluble fiber, containing partially hydrolyzed guar gum (Sunfiber), per 1000 mL . Thirty patients received total enteral nutrition postoperatively, and 70 patients received enteral supplementation . RESULTS: The patients receiving total enteral nutrition with soluble fiber had decreased diarrhea but increased flatulence . In none of these patients did enteral feeding have to be discontinued because of gastrointestinal side effects, whereas in four patients who were on a standard diet, enteral feeding had to be interrupted because of diarrhea (p < .05) . Similar observations were made in patients receiving enteral supplementation . In both groups, the incidence of diarrhea decreased significantly with the soluble fiber diet compared with the standard diet (6 vs 15, p < .05) . CONCLUSIONS: Enteral feeding with a formula supplemented with partially hydrolyzed guar gum reduces the incidence of diarrhea in patients receiving total enteral nutrition as well as in those receiving enteral supplementation, regardless of the cause of diarrhea . The increased hydrogen production and the significantly higher rate of flatulence are likely to result from fermentation of the soluble fiber in the colon, with concomitant production of short-chain fatty acids, which leads to increased absorption of short-chain fatty acids, sodium, and water by the colonocytes . This effect, together with the observed cholecystokinin-mediated decrease in colonic transit time with partially hydrolyzed guar gum, may explain the reduction in the incidence of diarrhea in this study.

J Dairy Sci, 1994 Nov, 77(11), 3426 - 31
Effect of aibellin, a peptide antibiotic, on propionate production in the rumen of goats; Hino T et al.; Aibellin was administered in feed to goats (16 to 18 kg of BW) for 12 d . At 80 mg/d, the molar percentage of propionate in rumen fluid increased significantly in 8 d, and the effect lasted for as long as 10 d after administration ceased . Total VFA concentration, protozoa numbers, and NDF digestibility were not depressed significantly at this dosage but were reduced at 100 mg/d with little further increase in the molar percentage of propionate . Therefore, the optimal dosage of aibellin was 80 mg/d under our experimental conditions . In contrast, monensin (30 mg/d) and gramicidin D (60 mg/d) decreased total VFA concentration and protozoa numbers when supplemented to obtain molar percentages of propionate comparable to 80 mg/d of aibellin . From these results, aibellin may be easier and safer to use than monensin and gramicidin D to modify rumen fermentation.

J Antibiot (Tokyo), 1994 Nov, 47(11), 1182 - 7
WIN 66306, a new neurokinin antagonist produced by an Aspergillus species: fermentation, isolation and physico-chemical properties; Barrow CJ et al.; WIN 66306 (1a), a cyclic peptide containing a novel amino acid, was isolated as a neurokinin antagonist from an Aspergillus species, labelled SC230 . Conditions that maximized the production of 1a were developed, leading also to production of the related compound WIN 68577 (2) and rosellichalasin (3) . Both 2 and 3 were more active in the rat NK1 than in the human NK1 receptor binding assay, while 1a was more active at the human receptor with an inhibitor affinity constant of 7 microM.

Curr Microbiol, 1994 Nov, 29(5), 263 - 8
The expression of the penicillin G amidase gene of Escherichia coli by primer extension analysis; Robas N et al.; Escherichia coli ATCC 11105 and JM109, transformed with a multicopy plasmid carrying the penicillin G amidase (PGA) gene, were grown at 26 degrees and 37 degrees C, in the presence or the absence of phenylacetic acid (PAA) or of glucose . A method based on primer extension was developed to quantify in vivo levels of PGA mRNAs . A unique transcription start site was found to be used in all the fermentation conditions tested . This site is located 28 nucleotides upstream of the initiation codon . Its utilization is subjected to catabolic repression and is induced by PAA . This site is used at 37 degrees C, but the PGA mRNA level in E . coli ATCC 11105 is lower at 37 degrees C than at 26 degrees C . Induction of the pga gene by PAA was found to be more efficient in the producer strain . Taking into account the amount of PGA mRNA present in the cells at 37 degrees C, one would expect the production of active PGA at this temperature . This is not the case . Thus, at 37 degrees C, expression is blocked at a step after transcription.

FEMS Microbiol Lett, 1994 Oct 15, 123(1-2), 137 - 44
Nutritional upshift response of ribosomal protein gene transcription in Saccharomyces cerevisiae; Griffioen G et al.; Switching Saccharomyces cerevisiae from non-fermentative to fermentative growth by adding glucose to a medium with glycerol as the sole carbon source, leads to a sudden increase in the rate of ribosomal protein gene transcription . By analyzing the nutritional shift response in a variety of yeast mutants and in the presence of different drugs, evidence was obtained that: (i) no de novo protein synthesis is required for this response; (ii) protein kinase A is essential, though independent of intracellular levels of cAMP, whereas protein kinase C is not involved; (iii) proper regulation of sugar phosphorylation is essential; (iv) glycolysis is required for the long term effect of the nutritional upshift; and (v) pathways leading to glucose-induced activation differ from those leading to gene repression, probably already at the level of glucose transport.

Int J Cancer, 1994 Oct 15, 59(2), 170 - 6
Fermented dairy products, dietary calcium and colon cancer: a case-control study in The Netherlands; Kampman E et al.; To examine whether the consumption of fermented dairy products or the dietary intake of calcium decreases colon cancer risk, a case-control study was conducted in the The Netherlands . Dietary patterns were assessed in detail (for cases before diagnosis or symptoms occurred) using a structured dietary history questionnaire . After adjustment for potential confounding variables, consumption of fermented dairy products, hard cheese and unfermented dairy products was not significantly associated with risk of colon cancer: an odds ratio (OR) of 1.1 was found for individuals consuming more than one serving of fermented dairy products per day as compared to those consuming less than 10% of one serving a day . Adjustment for dietary calcium attenuated the associations . Total dietary calcium was positively but non-significantly associated with colon cancer risk after adjustment for age, gender, urbanization level and total energy intake . Additional adjustment for a positive family history of colorectal cancer, cholecystectomy and energy-adjusted intake of total fat, dietary fibre, vitamin C and alcohol increased the association . No differences were observed between calcium from fermented and from unfermented dairy sources . The observed associations for fermented dairy products and dietary calcium differed between men and women: positive significant associations were observed in men, while in women non-significant inverse associations were found . Our results do not support the hypothesis that an increased intake of commercially available, commonly used fermented dairy products or dietary calcium decreases the risk of colon cancer.

FEMS Microbiol Lett, 1994 Oct 1, 122(3), 217 - 22
Pentose transport by the ruminal bacterium Butyrivibrio fibrisolvens; Strobel HJ; Butyrivibrio fibrisolvens is a fibrolytic ruminal bacterium that degrades hemicellulose and ferments the resulting pentose sugars . Washed cells of strain D1 accumulated radiolabelled xylose (Km = 1.5 microM) and arabinose (Km = 0.2 microM) when the organism was grown on xylose, arabinose, or glucose, but cultures grown on sucrose or cellobiose had little capacity to transport pentose . Glucose and xylose inhibited transport of each other non-competitively . Both sugars were utilized preferentially over arabinose, but since they did not inhibit transport of arabinose, it appeared that the preference was related to an internal metabolic step . Although the protonmotive force was completely abolished by ionophores, cells retained some ability to transport pentose . In contrast, the metabolic inhibitors iodoacetate, arsenate, and fluoride had little effect on protonmotive force but caused a large decrease in intracellular ATP and xylose and arabinose uptake . These results suggested that high-affinity, ATP-dependent mechanisms were responsible for pentose transport and hexose sugars affected the utilization of xylose and arabinose.

Br J Nutr, 1994 Oct, 72(4), 519 - 32
Gastro-jejunal digestion of soya-bean-milk protein in humans; Baglieri A et al.; In order to determine how soya-bean proteins are digested and metabolized in the human intestine before colonic bacterial fermentation and to estimate their true digestibility, the gastro-jejunal behaviour of soya-bean proteins in water and in two other forms (a concentrated soya-bean-protein solution (isolate) and a drink composed of crude soya-bean proteins (soymilk)) was studied in humans . Experiments were carried out in eight healthy volunteers using a double-lumen steady-state intestinal perfusion method with polyethyleneglycol (PEG) as a non-absorbable volume marker . Gastric emptying and N and electrolyte contents of the jejunal digesta were analysed . Gastric half-emptying time (min) of the liquid phase after water ingestion (12.59 (SE 0.12)) was shorter (P < 0.05) than those for soymilk (37.74 (SE 11.57)) and isolate (36.52 (SE 11.23)) . Electrolytic balances showed that for all meals, Na+, Cl- and K+ were secreted when Ca2+ was efficiently absorbed from the jejunal lumen . Gastro-jejunal N absorption for isolate and soymilk were 63 and 49% respectively, and were not significantly different from one another; after water ingestion, endogenous N was estimated to be 21 mmol . An estimate of the exogenous:endogenous values for the effluents was obtained from the amino acid compositions of soymilk and effluents after water or soymilk ingestion, indicating that 70% of the total N was exogenous and 30% endogenous . Under these conditions the endogenous fraction represented 31 mmol after soymilk ingestion and the gastro-jejunal N balance indicated that 54% of the soymilk was absorbed . This finding indicates that the true gastrojejunal digestibility of soya-bean proteins is similar to that of milk proteins.

Biotechnol Appl Biochem, 1994 Oct, 20 ( Pt 2), 185 - 98
Purification and characterization of the endocellular beta-glucosidase of a new strain of Candida entomophila isolated from fermenting agave (Agave sp.) juice; Gueguen Y et al.; A yeast strain isolated in the laboratory from fermenting agave (Agave sp.) juice was studied and classified as Candida entomophila . The beta-glucosidase of this yeast was purified by ion-exchange chromatography and gel filtration . Its molecular mass estimated by gel filtration was 400 kDa . The oligomeric structure was determined following treatment of the purified enzyme with SDS . Its optimum pH was between 5 and 6, and its optimum temperature was 60 degrees C . The enzyme was active against soluble glucosides with (1-->3)-beta, (1-->4)-beta and (1-->4)-alpha linkage configuration, and it possesses (1-->6)-alpha-arabinofuranosidase activity . It is competitively inhibited by glucose and by D-gluconic acid lactone . The enzyme was constitutive and a glucosyltransferase activity is observed in the presence of ethanol . Since the glycosides present in wines and fruit juices represent a potential source of aromatic flavour, the possible use of the yeast glucosidase for the liberation of the bound aroma is discussed.

Appl Environ Microbiol, 1994 Oct, 60(10), 3718 - 23
Effects of ruminal protozoa on cellulose degradation and the growth of an anaerobic ruminal fungus, Piromyces sp . strain OTS1, in vitro; Morgavi DP et al.; An anaerobic rumen fungus, Piromyces sp . strain OTS1, was incubated in the presence or absence of a mixed, A-type, protozoal population obtained from a goat, in a medium containing filter paper cellulose as energy source and antibiotics to suppress bacterial growth . Fermentation end products, cellulose degradation, and chitin as an indicator of fungal biomass were examined . In the presence of protozoa, total volatile fatty acids, notably propionate and butyrate, increased, and lactate decreased . In fungus-protozoan coincubations, formate was not detected at the end of the experiment and the amount of reducing sugars remained low throughout the incubation period . The fungal growth in the coincubations was negatively affected . While protozoal predation on zoospores was one mechanism of inhibition, mature fungal cells were also affected . Total cellulose degradation was greater in fungal monocultures, but the amount of cellulose degraded per unit of fungal biomass was 25% larger in the coincubations . The negative effects that the protozoal predatory activity had on the fungal growth and subsequently on the amount of cellulose degraded by Piromyces sp . strain OTS1 were partially attenuated by the protozoal fibrolytic activity or by an enhanced fungal activity due to a more favorable environment.

Int J Syst Bacteriol, 1994 Oct, 44(4), 641 - 5
Candida caseinolytica sp . nov., a new species of yeast occurring in necrotic tissue of Opuntia and Stenocereus species in the southwestern United States and Baja California, Mexico; Phaff HJ et al.; We describe Candida caseinolytica, a new yeast species which occurs in rotting tissues of opuntias and other cacti in the North American Sonoran Desert and a few other localities . This small-celled, slowly growing yeast does not ferment any sugar and assimilates a limited number of carbon compounds, including 2- and 5-ketogluconic acids . It exhibits strong extracellular proteolytic activity on casein at pH 6.5, but gelatin is not hydrolyzed or is only weakly hydrolyzed by a few strains . The type strain of C . caseinolytica is strain UCD-FST 83-438.3 (= ATCC 90546 = CBS 7781).

Int J Syst Bacteriol, 1994 Oct, 44(4), 599 - 602
Descriptions of Prevotella tannerae sp . nov . and Prevotella enoeca sp . nov . from the human gingival crevice and emendation of the description of Prevotella zoogleoformans; Moore LV et al.; Prevotella tannerae sp . nov . and Prevotella enoeca sp . nov . from the human gingival crevice are described . These organisms are obligately anaerobic, non-spore-forming, nonmotile, gram-negative, rod-shaped bacteria that ferment carbohydrates and produce succinic and acetic acids . Bile inhibits growth . Some strains (38%) of P . tannerae produce colonies with a tan to black pigment when they are grown on rabbit blood agar . The type strains are P . tannerae ATCC 51259 and P . enoeca ATCC 51261 . In addition, the description of Prevotella zoogleoformans is emended to exclude strains now recognized as members of Prevotella heparinolytica.

J Antibiot (Tokyo), 1994 Oct, 47(10), 1136 - 44
Structural elucidation of aibellin, a new peptide antibiotic with efficiency enhancing activity on rumen fermentation; Kumazawa S et al.; A new peptide antibiotic, aibellin, that had the efficiency enhancing activity on rumen fermentation, was isolated from the culture broth of the fungus, Verticimonosporium ellipticum D1528, and its primary structure was elucidated from spectrometric analysis and chemical degradation . Aibellin is a 20-residue peptaibol, and it has a unique structural feature in the novel C-terminal amino alcohol . Moreover, aibellin is the first peptaibol that possesses two acidic amino acids in the C-terminal region and a Phe residue in the middle of the sequence.

J Antibiot (Tokyo), 1994 Oct, 47(10), 1104 - 9
Nisamycin, a new manumycin group antibiotic from Streptomyces sp . K106 . I . Taxonomy, fermentation, isolation, physico-chemical and biological properties; Hayashi K et al.; Nisamycin, a new manumycin group antibiotic, was isolated from the culture broth of Streptomyces sp . K106 . This strain was designated to genus Streptomyces by the taxonomic features . Nisamycin was purified by ethyl acetate extraction, silica gel column chromatography, preparative silica gel TLC, and Sephadex LH-20 column chromatography as a pale yellow powder . Nisamycin is active against Gram-positive bacteria and fungi, and exhibits a cytotoxic activity.

J Antibiot (Tokyo), 1994 Oct, 47(10), 1084 - 91
WF11899A, B and C, novel antifungal lipopeptides . I . Taxonomy, fermentation, isolation and physico-chemical properties; Iwamoto T et al.; WF11899A, B and C, novel antifungal lipopeptide antibiotics were isolated from the culture broth of Coleophoma empetri F-11899 . These compounds belong to the echinocandin type of lipopeptides . Of these compounds, WF11899A showed good solubility in water . These three antibiotics possess potent in vitro antifungal activities against Candida spp.

Comp Biochem Physiol Physiol, 1994 Oct, 109(2), 431 - 6
Fibre utilization by Kalahari dwelling subterranean Damara mole-rats (Cryptomys damarensis) when fed their natural diet of gemsbok cucumber tubers (Acanthosicyos naudinianus); Buffenstein R et al.; Kalahari dwelling Damara mole-rats (Cryptomys damarensis) naturally feed on a high fibre diet of underground gemsbok cucumber tubers, Acanthosicyos naudinianus . We investigated the degree of fibre utilization and fermentation on this diet by measuring caecal characteristics (namely temperature, pH and weight) and in vitro rates of gas and short chain fatty acid (SCFA) production in these underground dwelling hind-gut fermentors . Rectal temperatures (33.8 +/- 0.6 degrees C) were consistently higher than caecal temperatures (33.3 +/- 0.6 degrees C) . Furthermore, a 0.8 degrees C gradient of temperatures existed within the caecum, with the lowest temperature occurring in the corpus caeci . Both rates of gas production (4.74 +/- 0.6 ml/g dry matter/hr) and SCFA production (266.80 +/- 9.251 mumol/caecum per hr) were high, with proportionately more acetic acid produced than any other SCFA . Nevertheless, the initial concentrations of SCFAs present in the caecum were low (52 +/- 17 mM) implying a rapid rate of absorption of these SCFAs . The high rates of fermentation provide a considerable amount of energy that would otherwise be trapped in fibre and thus unavailable to the animal . This highly efficient caecal fermentation enables the Damara mole-rat to maximally exploit the underground food resources in the arid-zone ecotope.

Arch Biochem Biophys, 1994 Oct, 314(1), 50 - 63
Purification of biologically active SPARC expressed in Saccharomyces cerevisiae; Yost JC et al.; SPARC (secreted protein, acidic and rich in cysteine) is a secreted, Ca+2-binding glycoprotein that modulates interactions between cells and their immediate extracellular matrix . Traditional sources of SPARC have been mammalian bone, platelets, a basement membrane tumor, and cultured cells; most if not all preparations, however, contain platelet-derived growth factor and one or more serum proteins that bind specifically to purified SPARC . To avoid these contaminants, as well as the toxic lipid moiety associated with endotoxin, we expressed recombinant wild-type and a mutated murine SPARC in two strains of Saccharomyces cerevisiae: one strain was transfected with an expression vector encoding a proprietory signal peptide that directed the secretion of the recombinant protein . Recombinant SPARC was also purified from cell lysates of a different, nonreverting strain of S . cerevisiae that was optimized for large-scale fermentation runs . A mutant murine SPARC lacking the single glycosylation site was also expressed following substitution of Asn98 with Asp98 in the wild-type sequence . Purification of SPARC was achieved by copper-affinity and hydrophobic-interaction chromatography . Both the wild-type and the glycosylation-defective recombinant proteins exhibited high levels of activity in two bioassays with endothelial cells: inhibition of cell spreading/disruption of actin microfilaments and competition for the binding of nonrecombinant 125I-labeled SPARC to the cell surface . The availability of biologically active, recombinant SPARC will facilitate investigation of the structural and functional properties of this protein, which is expressed at high levels in healing wounds, atherosclerotic plaque, and several cancers and diseases of connective tissue.

Yeast, 1994 Oct, 10(10), 1311 - 9
Detection of polygalacturonase, pectin-lyase and pectin-esterase activities in a Saccharomyces cerevisiae strain; Gainvors A et al.; The catalytic capacity of several excreted pectinolytic enzymes obtained from various yeast strains was examined using in vivo and biochemical techniques . Of the 33 yeast strains studied, 30 were isolated from champagne wine during alcoholic fermentation . Only one yeast strain was found to excrete pectinolytic enzymes and was identified as Saccharomyces cerevisiae and designated SCPP . Pulsed-field gel electrophoresis and the polymerase chain reaction technique were used to characterize further this specific strain . Three types of pectinolytic enzymes were found to be excreted by SCPP: polygalacturonase, pectin-lyase and pectin-esterase . These enzymes allow pectin hydrolysis during cell growth.

Int J Biol Macromol, 1994 Oct, 16(5), 253 - 8
Influence of the method of purification on some solution properties of welan gum; Lopes L et al.; The origin and some consequences of the presence of aggregates and impurities (deriving from the fermentation procedure) on the solution properties of welan gum have been studied . For this purpose, a method of purification was developed for a fermentation welan broth . It was verified that this method is ineffective for the dissociation of aggregates in the commercial product . This demonstrates the irreversible nature of the intermolecular interactions of welan samples isolated by precipitation in the presence of impurities . The purified products were characterized (Mw, {eta}, kH) and the results were compared to those obtained from commercial samples of welan . The influence of the method of purification on the rheological properties was analysed.

J Nutr Sci Vitaminol (Tokyo), 1994 Oct, 40(5), 467 - 77
Antioxidative effects of a processed grain food; Minamiyama Y et al.; Antioxidant biofactor: AOB is a unique processed grain food . It is a yellow-green powder . It contains the following extracts: germ extracts, soybean, rice bran, tear grass, sesame, wheat, citron, green tea, green leaf extract, and malted rice . These materials were slowly roasted under a powdered oure at less than 60 degrees C and fermented with Aspergillus oryzae over 3 days to transform each ingredient into low molecular weight substances . These conditions were different by each material, environmental humidity and temperature . It probably contains a variety of substances having antioxidant activity including flavonoids, alpha-tocopherol, vitamin C, and tannins . We investigated its antioxidative properties using electron spin resonance (ESR) and autoxidation of rat brain homogenates . The superoxide, hydroxyl radical, and the stable free radical, diphenyl-p-picrylhydrazyl (DPPH) radical scavenging activity of AOB was investigated using ESR spectrometry . In an in vitro study, a suspension of AOB was added directly to a superoxide generating system (hypoxanthine-xanthine oxidase; HX/XO) and investigated using 5,5-dimethyl-1-pyrroline-N-oxide (DMPO) as a spin trapping agent . At final concentrations of 0.01, 0.05, and 0.1 mg/ml, AOB dose-dependent scavenging activity was observed as 0.103, 0.619, and 1.369 U/ml, respectively . A concentration of 1.0 mg/ml completely scavenged DMPO-OOH signals; 1.0 mg/ml of AOB inhibited the DMPO-OH signal generated by Fenton's reaction, but its inhibitory effect was not competitive, and was inhibition of the Fenton's reaction . 1.0, 3.0, and 5.0 mg/ml of AOB were significantly inhibited the DPPH radical . In an in vivo study, rats were fed AOB orally at doses of 1 or 5 g/day for 24 h or for 3 days and the superoxide scavenging activity was measured in plasma . With the administration of 1 g/day for 3 days, the superoxide scavenging activity was about 1.8 times that of the control group fed a basal diet; 1.5 times the control with 5 g/day for 1 day, and 2.6 times the control with 5 g/day for 3 days, all of which represented significant increases in superoxide scavenging activity . AOB strongly inhibited the autoxidation of rat brain homogenates in vitro in a dose-dependent manner . However, each ingredient before roast and fermentation little inhibited lipid peroxidation . Roasting and fermentation with A . oryzae way be important to transform each ingredient into low molecular weight substances . Therefore, it was suggested that AOB possesses strong antioxidant and free radical scavenging activities.

Curr Genet, 1994 Oct, 26(4), 295 - 301
The byp1-3 allele of the Saccharomyces cerevisiae GGS1/TPS1 gene and its multi-copy suppressor tRNA(GLN) (CAG): Ggs1/Tps1 protein levels restraining growth on fermentable sugars and trehalose accumulation; Hohmann S et al.; Byp1-3 is an amber nonsense allele of the Saccharomyces cerevisiae GGS1/TPS1 gene which encodes the small subunit of the trehalose synthase complex . Mutations in this gene confer an inability to grow on glucose or fructose but the phenotype of byp1-3 mutants is leaky in a strain-dependent manner . Overexpression of the isolated byp1-3 allele suppressed the growth defect of a ggs1/tps1 delta mutant . Expression of an in-vitro-generated mutant allele of GGS1/TPS1 that lacks all the coding sequences downstream from the byp1-3 mutation led to the production of a shortened protein that did not complement the ggs1/tps1 delta mutant . We have isolated, as an allele-specific multi-copy suppressor of the growth defect of the byp1-3 mutant on fructose, the gene for tRNA(GLN) (CAG) . Thus the leaky phenotype of byp1-3 mutants is due to a low level of read through of the internal nonsense codon by tRNA(GLN) (CAG) . Using overexpression of the isolated byp1-3 allele, as well as of the tRNA(GLN) (CAG) gene, we were able to demonstrate that as little as about 10% of the normal Ggs1/Tps1 protein level is sufficient for slow growth on fructose . We also show a correlation between the level of Ggs1/Tps1, the ability to accumulate trehalose in stationary phase and the ability to grow on fermentable sugars . Sequence analysis of the cloned tRNA(GLN) (CAG) gene showed that it is located 700 bp upstream of URA10 . However, we found considerable differences to the reported sequence of URA10, in particular in the non-coding region.

Clin Investig, 1994 Oct, 72(10), 742 - 8
Colonic fermentation: metabolic and clinical implications; Soergel KH; Colonic SCFA formation from fermentable carbohydrate is important for the maintenance of morphologic and functional integrity of the colonic epithelium . Carbohydrate-induced diarrhea occurs when the amount of carbohydrate entering the colon exceeds its fermentation capacity . Deficient availability or utilization of SCFA, mainly of n-butyrate, is the cause of diversion colitis and may play important roles in colonic carcinogenesis, in starvation and enterotoxigenic diarrhea, and in idiopathic UC.

Plant Foods Hum Nutr, 1994 Oct, 46(3), 201 - 5
Nutritional improvement of lentils, chick pea, rice and wheat by natural fermentation; Shekib LA; Effect of natural fermentation process (4 days) on the non-protein nitrogen, crude and true protein, amino acids content and in vitro digestibility of two kinds of legumes (lentils and chick pea) and two kinds of cereals (rice and wheat) was investigated . Non-protein nitrogen increased significantly (p < 0.001) in the fermented products . Little increase has occurred in the crude protein while no significant change was observed in the fermented true protein samples . It was observed that methionine and cystine which are considered the limiting amino acids in legume seeds were close to those of FAO/WHO patterns . Also, lysine content (the first limiting amino acid in cereals was higher in fermented rice than that of FAO/WHO pattern . Moreover, fermentation process improved significantly, the in vitro digestibility of both legume and cereal products.

J Dairy Sci, 1994 Oct, 77(10), 3209 - 35
Fermentation and utilization of grass silage; Harrison JH et al.; The decision to utilize particular forages in support of dairy production should be based on a number of key factors, such as available land base, type of manure management, soil type and topography, climate, and availability of purchased forages and feeds . Because of the complexity and environmental concerns existing in the dairy industry today, decisions about forage and manure management should include whole farm analysis with the aid of computer software . The chemical composition and digestibility of grass are affected more by stage of maturity than by other management factors, such as species, DM, or type of harvest system . The decline in digestibility of nutrients in first growth forage is approximately .55 to .68%/d and is dependent on the method of estimation . The decline in digestible DMI in first growth is .3 to .5%/d . The use of silage additives has become an integral part of forage management, and improvements in DMI and milk production are documented . Particle size and type of harvest equipment significantly affect eating behavior and efficiency of milk production . Wilting of silage results in an increase in DMI and efficiency of microbial protein production.

J Dairy Sci, 1994 Oct, 77(10), 3081 - 6
Response to various amounts of Aspergillus oryzae fermentation extract on ruminal metabolism in cattle; Varel VH et al.; The objective of this study was to determine whether Aspergillus oryzae fermentation extract stimulated or inhibited ruminal fermentation when fed at higher than recommended doses (3 g/d) . Four dietary treatments of A . oryzae fermentation extract were fed daily to six cows fitted with ruminal cannulas . For each of four periods, bromegrass hay (6% CP) with and without extract was fed for 28 d . Dacron bags containing bromegrass cell walls were ruminally incubated to determine ruminal fiber degradation . The A . oryzae fermentation extract did not affect degradation of cell walls, cellulose, or hemicellulose . Total ruminal anaerobic or cellulolytic bacteria were not different among treatments; neither were the proportions of cellulolytic species, Butyrivibrio sp., Ruminococcus albus, or Ruminococcus flavefaciens . Ruminal ammonia was not different; however, total VFA were higher, and pH tended to be lower, when 27 g/d of A . oryzae fermentation extract was fed . The proportion of VFA was not different among treatments . The A . oryzae fermentation extract fed at nine times the recommended dosage did not produce any stimulatory effects, except for total VFA, and was not inhibitory or toxic to ruminal metabolism and forage fiber degradation.

J Dairy Sci, 1994 Oct, 77(10), 3073 - 80
Effect of yeast cultures on performance of lactating dairy cows: a field study; Swartz DL et al.; Three hundred six lactating Holstein cows in the first 120 d of lactation from seven farms in Pennsylvania were used to evaluate supplementation of two Saccharomyces cerevisiae yeast cultures containing about 10(8) cfu/g viable yeast cells on milk production and composition . Cows were fed individually and grouped into three blocks based on lactation numbers 1, 2, and 3 or greater, and, within block, randomly assigned to one of three treatments for a 14-wk study . The three treatments were 1) control, 2) yeast culture fermented on ground cornmeal and corn gluten meal (5.3 x 10(10) cfu/d per cow), and 3) yeast culture fermented on cornmeal and soybean meal (5.1 x 10(10) cfu/d per cow) . The three treatments were mixed with cornmeal and 114 g per cow was fed daily as a top-dressing . Milk production, milk fat and protein percentage, milk fat and protein production, and 3.5% FCM were not affected by either yeast treatment . There were no significant interactions of farm by treatment, lactation number by treatment, or week by treatment . No differences in performance were significant for early lactation cows that calved during the trial, but FCM tended to be higher for treatment than for the control cows . Daily DMI measured on 39 cows at one location did not differ among treatments . Yeast supplementation was not beneficial for any production parameters under the nutritional management programs of these seven dairy farms.

J Dairy Sci, 1994 Oct, 77(10), 2934 - 9
Determination of organic acids during the fermentation and cold storage of yogurt; Fernandez-Garcia E et al.; The objective of the present study was the separation and quantification of orotic, citric, pyruvic, lactic, uric, formic, acetic, propionic, butyric, and hippuric acids in a single isocratic analysis by HPLC . Two methods of extraction were compared: 1) acetonitrile and water and 2) .01N H2SO4 . Recoveries of orotic, lactic, acetic, and propionic acids were 90% for both methods . Recoveries of citric, pyruvic, uric, butyric, and hippuric acids were not satisfactory with the acetonitrile method, but were acceptable using the H2SO4 extraction procedure . Yogurts were manufactured under laboratory-scale conditions, and samples were analyzed during fermentation and after storage at 4 degrees C . Samples were analyzed for pH and organic acids . All of the organic acids exhibited varying degrees of increases and decreases during fermentation and storage . Formic and butyric acids were not detected under the conditions of this study.

Eur J Clin Nutr, 1994 Oct, 48(10), 692 - 701
Intestinal transport and fermentation of resistant starch evaluated by the hydrogen breath test; Olesen M et al.; OBJECTIVE: To study fermentability of different samples of resistant starch (RS), compared to one another and to lactulose, and to study the effect on gastric emptying of addition of RS to test meal . Finally to study if adaptation to RS results in a measurable change in fermentation pattern, (H2/CH4 production) . Sources of RS: Raw potato starch (RPS), 58% RS; corn flakes (CF), 5% RS; hylon VII high amylomaize starch, extrusion cooked and cooled (HAS) 30% RS; highly retrograded hylon VII high amylomaize starch (HRA) 89% RS . DESIGN: (1) Fermentation: seven healthy volunteers ingested in randomized order 50 g RPS, 100 g CF, 75 g HAS, 25 g HRA . End-expiratory H2/CH4 was measured every 30 min for 12 to 22 hours post-ingestion as a measure of fermentation . A dose-response study of RPS, 5, 10, 25, 50, 75 and 100 g was performed . (2) Adaptation: In five 3-week periods seven volunteers added daily to their usual diet 50 g of either RPS, HAS, oat bran, wheat bran or common maize starch . The polysaccharides were administered in randomized order . The test periods were separated by 1 week's wash out . Basic end-expiratory H2/CH4 was measured once a week prior to and during the test periods . (3) Gastric emptying: The rate of increase in blood glucose was measured after test meals consisting of 50 and 100 g of RPS, 50 g HAS and 50 g glucose dissolved in a gel, alone, and mixed with 25 g of RPS . As controls we chose wheat bran and oat bran . RESULTS: (1) We found that RPS is fermentable, although the cumulated excessive H2 production after 50 g RPS corresponding to 29 g RS was clearly less than after 10 g lactulose . The time from ingestion of RPS to a sustained increase in end-expiratory H2 (apparent transit time; 5-11 h) was longer than lactulose (1-4 h), indicating either a slow passage through the small intestine or a slow fermentation rate . 100 g of corn flakes (4.6 g RS) resulted in a measurable increase in H2 production, equivalent to 10-20 g RPS, whereas neither of the two samples of hylon VII high amylomaize resulted in any significant increase in H2 production . The dose-response study with RPS showed that even 5 g of RPS resulted in a measurable increase in end-expiratory H2, and increasing doses from 5 g to 100 g resulted in a seemingly exponential increase in H2 production . (2) 3 weeks' daily administration of HAS resulted in a slightly elevated increase in basic end-expiratory H2, although the increase did not reach statistical significance . RPS resulted in a sustained increase in basic end-expiratory H2 . Both RS samples increased measurable end-expiratory CH4 in volunteers with measurable CH4 production after a lactulose load, but 3 weeks' daily challenge with these slowly fermentable substrates did not increase measurable CH4 in volunteers, who prior to the study only produced CH4 intermittently . (3) The rate of increase in blood sugar was unaffected by addition of RS or non-starch-polysaccharides to the test meal, indicating that addition of the polysaccharides does not affect gastric emptying . CONCLUSIONS: A fraction of RPS is resistant to digestion in the small intestine, and it is fermentable by the colonic microbial flora . RS from CF, HAS and RPS give very different H2 responses, either due to differences in digestion patterns or fermentation patterns . Short-term adaptation (3 weeks) to HAS or RPS does not change the H2/CH4 response . RS does not affect gastric emptying of a test meal consisting of glucose dissolved in a gel.

Ophthalmologe, 1994 Oct, 91(5), 676 - 9
{No detection of mycoplasma in 205 conjunctival swabs}; Grasbon T et al.; Mycoplasma is known to cause pulmonary and urogenital infections in humans . A pathogenicity for the human eye never has been assessed, although they have been observed in the peripheral eye in a few cases of acute and non-specific conjunctivitis, in patients with Reiter's disease and in newborns . Due to the absence of cell walls, mycoplasma is only sensitive to a few antibiotics . Therefore, we presume that mycoplasma has a role in non-specific and chronic conjunctivitis . It is conceivable that in HIV-positive patients the risk of opportunistic colonization of the conjunctiva by mycoplasma is increased . PATIENTS AND METHODS . Between January and December 1992, 205 conjunctival swabs of 151 patients were prospectively analyzed for mycoplasma . The group contained 51 HIV-infected patients (94 swabs) . A total of 85 swabs were from non-irritated eyes and the remaining (120) from peripherally inflamed eyes, mainly diagnosed as non-specific or chronic conjunctivitis (75 swabs) . Specimen were obtained from the inferior fornix conjunctivae by use of a moistened cotton swab, which was directly immersed in culture broth . For subsequent culture, we used a liquid and a solid mycoplasma medium to differentiate Mycoplasma hominis, Mycoplasma fermentans and Ureaplasma urealyticum . In 77 swabs, a second sample was taken, which was investigated at the Institute for Poultry Diseases of the Ludwig Maximilians University, Munich . OUTCOME . None of 205 swabs, including the 77 samples tested in parallel, gave positive results for mycoplasma . Six cases were positive for bacteria and five cases for fungi . CONCLUSION . In adult patients at the Munich University Eye Hospital with either non-irritated eyes or non-specific and chronic conjunctivitis, no mycoplasma could be detected . With regard to HIV infection, there is no indication that mycoplasma plays a role in opportunistic infections of the conjunctiva.

Appl Microbiol Biotechnol, 1994 Oct, 42(1), 67 - 72
Effects of the amplification of the genes coding for the L-threonine biosynthetic enzymes on the L-threonine production from methanol by a gram-negative obligate methylotroph, Methylobacillus glycogenes; Motoyama H et al.; We constructed recombinant plasmids carrying the genes coding for the L-threonine biosynthetic enzymes, the hom gene, the hom-thrC genes, and the thrB genes, of a gram-negative obligate methylotroph, Methylobacillus glycogenes, and examined the effects of them on the production of L-threonine from methanol . The hom gene, which encodes the homoserine dehydrogenase, and the hom-thrC genes, containing the gene coding for threonine synthase together with the hom gene, were cloned from a wild-type strain, and the thrB gene encoding the desensitized homoserine kinase was cloned from an L-threonine-producing mutant, ATR80 . The recombinant plasmids were transferred into ATR80 and its L-isoleucine auxotroph, A513, by conjugation . Amplification of the genes coding for the L-threonine biosynthetic enzymes elevated the activities of the L-threonine biosynthetic enzymes of the transconjugants 10- to 30-fold over those of the strains containing only vectors . The L-threonine production from methanol in test-tube cultivation was increased about 30% and 40% by the amplification of the hom gene and the hom-thrC gene respectively, and it was slightly increased by that of the thrB gene . The effects of gene amplification were confirmed by the cultivation in 5-1 jar fermentors . The best producer, an A513 transconjugant containing the plasmid carrying the hom-thrC genes, produced 16.3 g/l L-threonine for 72 h.

Appl Microbiol Biotechnol, 1994 Oct, 42(1), 36 - 9
Purification of secreted alpha-amylases by immunoaffinity chromatography with cross-reactive antibody; Katoh S et al.; Two isozymes of rice alpha-amylases expressed and secreted by recombinant yeast were purified by immunoaffinity chromatography by using cross-reactive antibody . Antibodies raised against partially purified barley alpha-amylase adsorbed rice alpha-amylases in fermentation broth by a cross-reaction . By use of these antibodies as ligands, rice alpha-amylases were concentrated and purified to a high degree in one-step immunoaffinity chromatography . Because of the differences in the contaminating impurities between the barley alpha-amylase (antigen) from barley malt and rice alpha-amylases (target protein) secreted from yeast, the high purity of eluted alpha-amylases was attained without the use of highly purified antigen for immunization . Utilization of cross-reactive antibodies in immunoaffinity chromatography is useful for the purification of recombinant proteins in the absence of a sufficient amount and high enough purity of the target proteins to be purified.

AIDS Res Hum Retroviruses, 1994 Oct, 10(10), 1251 - 7
Inhibition of HIV type 1 reverse transcriptase assay by nucleases produced by contaminating mycoplasmas; Quillent C et al.; Mycoplasmal contamination of HIV-1-infected cells has been found to induce reduction of reverse transcriptase (RT) activity; however, the exact mechanism of this phenomenon was not clearly elucidated . Our results indicate that the apparent reduction in RT activity is due to a calcium-dependent nuclease(s) that is (are) produced by contaminating mycoplasmas . The interference with the RT assay was found to be due to the degradation of products of the RT activity . Addition of EGTA at a 1 mM concentration was sufficient to remove the inhibitory effect . The particular HIV-1-producing cell line that was under study was found to be contaminated with Mycoplasma fermentans and Mycoplasma pirum and the latter was isolated in pure culture . Nuclease activity was also observed with pure cultures of mycoplasmas from different species . The activity was found to be of the endonuclease type because it was active with both supercoiled and linear DNAs.

Appl Environ Microbiol, 1994 Oct, 60(10), 3697 - 703
The use of 16S rRNA-targeted oligonucleotide probes to study competition between ruminal fibrolytic bacteria: pure-culture studies with cellulose and alkaline peroxide-treated wheat straw; Odenyo AA et al.; Specific oligonucleotide probes targeted to sites on the 16S rRNA of Ruminococcus albus 8, Ruminococcus flavefaciens FD-1, and Fibrobacter succinogenes S85 and a domain Bacteria probe were used to study bacterial interactions during the fermentation of cellulose and alkaline hydrogen peroxide-treated wheat straw in monocultures, dicultures, and tricultures . Results showed that R . albus 8 inhibited the growth of R . flavefaciens FD-1 when grown as a diculture with cellulose or alkaline hydrogen peroxide-treated wheat straw as the carbon source . In dicultures containing R . albus 8 and F . succinogenes S85 grown on cellulose or alkaline hydrogen peroxide-treated wheat straw, competition was not detected . R . flavefaciens FD-1 outcompeted F . succinogenes S85 when cellulose was used as the carbon source . In tricultures with cellulose as the carbon source, R . flavefaciens FD-1 was inhibited, R . albus 8 appeared to dominate during the early phase of degradation (12 to 48 h), while F . succinogenes S85 became predominant during the later phase of degradation (60 to 70 h) . When alkaline hydrogen peroxide-treated wheat straw was used as a growth substrate, F . succinogenes S85 showed better growth than either R . albus 8 or R . flavefaciens FD-1 . However, R . flavefaciens FD-1 was present in small numbers throughout the incubation period, unlike the growth patterns when cellulose was the carbon source.

Biochem Biophys Res Commun, 1994 Sep 30, 203(3), 1567 - 73
Rescue of yeast defective in mitochondrial ATP synthase subunit 8 by a heterologous gene from Aspergillus nidulans; Straffon AF et al.; Mitochondrial ATP synthase subunit 8 of the yeast Saccharomyces cerevisiae and of the filamentous fungus Aspergillus nidulans have the same length and similar structural motifs . However, the two proteins share only 50% identical residues, with the conserved residues being concentrated in the N- and C-terminal domains . We have investigated whether it is amino acid sequence or overall structural motifs that are required for subunit 8 function . PCR was used to construct a gene encoding A . nidulans subunit 8 fused to an N-terminal cleavable mitochondrial targeting sequence . Following expression in the nucleus of a yeast strain deficient in subunit 8, the chimaeric precursor targeted the subunit 8 protein back to the mitochondrion . The A . nidulans subunit 8 was found to be able to restore growth on non-fermentable substrate at 18 degrees C and 28 degrees C, but not at 36 degrees C . Given the sequence divergence between subunit 8 of A . nidulans and that of S . cerevisiae, this finding suggests that common structural motifs are important for subunit 8 function.

J Med Chem, 1994 Sep 30, 37(20), 3389 - 99
Conformationally locked nucleoside analogues . Synthesis of dideoxycarbocyclic nucleoside analogues structurally related to neplanocin C; Rodriguez JB et al.; The glycon moiety of nucleosides in solution is known to exist in a rapid dynamic equilibrium between extreme northern and southern conformations as defined by the pseudorotation cycle . The concept of preparing rigid nucleoside analogues with the glycon conformation locked in one of these two extremes was tested with the synthesis of some cyclopropane-fused dideoxycarbocyclic nucleosides, similar to the well-known class of anti-HIV active dideoxynucleosides . The new compounds described here are dideoxynucleoside analogues of the fermentation product neplanocin C (6) which exhibits a typical northern geometry for its 6-oxabicyclo{3.1.0}hexane pseudosugar moiety . However, in view of the lability of the epoxide ring in this system, the equivalent cyclopropane-fused bicyclo{3.1.0}hexane system was used instead to prepare the corresponding dideoxynucleoside analogues bearing all the common bases {(+/-)-9-13} . Due to the well-documented preference of unrestricted bicyclo{3.1.0}hexane systems to exist exclusively in a boat conformation, the resulting nucleosides are structurally locked in a typical northern conformation similar to that of neplanocin C . The locked northern conformation in these nucleosides remained unchanged in solution in the 20-80 degrees C temperature range according to variable temperature 1H NMR studies . For the synthesis of these compounds, racemic trans-1-{(benzyloxy)methyl}-4-hydroxybicyclo{3.1.0}hexane {(+/-)-18} was prepared by a samarium-promoted cyclopropanation reaction with the antecedent cyclopentenol . All of the bases were incorporated under Mitsunobu conditions and converted to the desired final products following a standard methodology . Anti-HIV evaluation revealed that only the adenosine analogue (+/-)-9 possessed enough activity to warrant resolution into its optical antipodes . This was realized by chiral HPLC chromatography to give the individual enantiomers (-)-32 and (+)-33 . Adenosine deaminase was used to identify isomer (+)-33 as the enantiomer with the "natural" configuration which was solely responsible for the observed biological activity and toxicity of (+/-)-9 . It is possible that the exclusive northern conformation adopted by these nucleosides reduces their substrate affinity for the various activating kinases, except in the case of the adenosine analogue.

Biochim Biophys Acta, 1994 Sep 28, 1201(1), 41 - 50
Ontogenic and nutritional modifications in the intestinal fucosylation process at the weaning period . Influence of dietary fibers; Tardy F et al.; In the rat small intestine, the glycosylation changes which normally take place at the weaning period are characterized by a shift from sialylation to fucosylation . The introduction of dietary fibers at weaning is one of the more striking nutritional modification so that some authors have suggested that the presence of fibers and the development of colonic fermentation might be important for the development of the small intestine, as for the colon . In order to define the respective contribution of ontogenic and nutritional factors to the intestinal glycosylation changes at this period, some aspects of the intestinal glycosylation were studied in five groups of rats (16-day-old suckling rats, prolonged nursing 23-day-old rats, 23-day-old rats weaned at day 19 with either a fiber-free, a cellulose or a pectin diet) . Intestinal glycoproteins of suckling rats are characterized by a low fucose content and a high proportion of mannose . The amounts of the neutral sugars (fucose, mannose and galactose), expressed either per gram of intestine or for one intestine, are always higher in the fiber-fed groups than in the prolonged-nursing group or the group fed the fiber-free diet . Activities which promote fucosylation process (GDP-fucose production and fucosyltransferase activities) and those which are opposed to fucosylation (endogenous inhibitor of fucosyltransferase and GDP-fucose pyrophosphatase) are strongly modified in opposite ways at day 23 as compared to day 16 . These modifications depend on the age of the animal (ontogenic factors) with additional modifications induced by the dietary factors . In particular, similar sugar contents and patterns are obtained with cellulose and pectin diets though the enzymatic activities of the fucosylation pathway are very different . No correlation was found between the caecal content of short chain fatty acids and any of the parameters under study . Thus, dietary fibers induce metabolic changes in the small intestine glycosylation in short-term experiments independently of colonic fermentation . Besides, these results point out that the consideration of fucosyl-transferase activities alone are not sufficient to predict glycoprotein fucose content and that other regulatory sites are involved . Dietary manipulations at the weaning period could represent a good model for the study of glycosylation regulation.

FEMS Microbiol Lett, 1994 Sep 15, 122(1-2), 27 - 32
Fermentative degradation of acetone by an enrichment culture in membrane-separated culture devices and in cell suspensions; Platen H et al.; A mixed culture, WoAct, growing on acetone, consisted of two dominant morphotypes: a rod-shaped acetone-fermenting bacterium producing acetate, and an acetate-utilizing Methanosaeta species . Dense cell suspensions, largely free of the aceticlastic methanogen and supplemented with bromoethanesulfonate, were able to degrade acetone and grow in small volumes in membrane-separated culture devices in which the acetate produced could diffuse into a large volume of medium . Acetone degradation and growth halted when the acetate concentration reached about 10 to 12 mM . Cell suspensions were able to degrade acetone in the absence of active methanogenesis, but the addition of 10 mM acetate inhibited acetone metabolism . Addition of an active culture of Methanosaeta sp . greatly stimulated the rate of acetone degradation . The results show that acetate removal in the mixed culture is not a prerequisite for growth and acetone degradation by the acetone-fermenting bacterium.

J Ambul Care Manage, 1994 Oct, 17(4), 77 - 81
The equity model: three commentaries; Weis EI et al.; In the current ferment of health care reform, advocates of most proposals agree that one of the goals to be achieved is maintaining an environment in which physicians and other caregivers can be comfortable . One such proposal, the equity model, is evaluated here from the physician's viewpoint by three directors of established health care plans . While all express concern over potential loss of physicians' autonomy and control, they see the threat as coming from different sources.

Gastroenterology, 1994 Sep, 107(3), 637 - 42
Colonic fermentation and nutritional recovery in rats with massive small bowel resection; Aghdassi E et al.; BACKGROUND/AIMS: After massive small bowel resection, malabsorbed carbohydrates reach the colon and undergo fermentation . This study investigates the role of colonic fermentation in rats with 80% small bowel resection on weight gain, nitrogen balance, body composition, and intestinal adaptation . METHODS: Resected or transected rats were fed a liquid diet enterally for 16 days with or without 30 mg/kg metronidazole to reduce fermentation . Weight gain was monitored until the rats were killed . Carcass composition, short-chain fatty acids in cecal content, total nitrogen output, and intestinal mucosal dry weight, protein, and DNA were measured . RESULTS: Resected rats without metronidazole had a significantly better weight gain, carcass protein, nitrogen balance, and mucosal dry weight, protein, and DNA compared with that of resected rats receiving metronidazole . There were no significant differences between the two transected groups . CONCLUSIONS: Decreasing colonic fermentation, measured by short-chain fatty acids in cecal content, reduced intestinal adaptation and nutritional recovery in rats with massive small bowel resection.

J Bacteriol, 1994 Sep, 176(17), 5423 - 8
Anaerobic regulation of the hydrogenase 1 (hya) operon of Escherichia coli; Brondsted L et al.; Using a transcriptional fusion to the lacZ gene, we have analyzed the anaerobic regulation of the hydrogenase 1 (hya) operon in response to different anaerobic growth conditions and to mutations in regulatory genes . We found that the transcription of the hya operon was induced when the growth condition was changed from aerobic to anaerobic and that this induction was independent of Fnr but dependent on regulators AppY and ArcA . Furthermore, we found that the transcription of the hya operon was not regulated by the cyclic AMP-cyclic AMP receptor protein complex . Investigation of the effects of different anaerobic growth conditions on the expression of the hya operon showed that expression was induced by formate and repressed by nitrate . Formate induction was not mediated by the fhlA gene product, and nitrate repression was not mediated by the narL gene product . We found a high level of anaerobic expression of the hya operon in glucose medium supplemented with formate and in glycerol medium supplemented with fumarate, suggesting that hydrogenase isoenzyme 1 has a function during both fermentative growth and anaerobic respiration.

Infect Immun, 1994 Sep, 62(9), 3916 - 21
Induced mouse spleen B-cell proliferation and secretion of immunoglobulin by lipid-associated membrane proteins of Mycoplasma fermentans incognitus and Mycoplasma penetrans; Feng SH et al.; Mycoplasmas have been implicated as a possible cofactor in AIDS pathogenesis . Mycoplasma fermentans and M . penetrans infect human immunodeficiency virus-positive patients at a significantly higher frequency than non-human immunodeficiency virus-infected control subjects . Various mycoplasmal membrane preparations are known to affect the functions of immune cells both in vitro and in vivo . A group of lipid-associated membrane proteins (LAMPs) extracted by Triton X-114 from mycoplasmas are major antigenic targets of human host antibody responses . In this study, LAMPs prepared from both M . fermentans and M . penetrans nonspecifically stimulated spleen cells of CBA/CaH mice to proliferate . LAMPs were also stimulatory to spleen cells from athymic mice . On the other hand, enriched splenic T cells from CBA/CaH mice with or without accessory cells responded poorly . Thus, the mitogenic effect of mycoplasmal LAMPs appeared mainly on B cells . High levels of immunoglobulin (Ig) M and low but detectable amounts of IgG were found in the supernatant of LAMP-treated splenic cell culture . M . penetrans LAMPs had a much more potent effect on murine spleen cells than did M . fermentans incognitus LAMPs in inducing both B-cell proliferation and Ig secretion . In conclusion, the mycoplasmal LAMPs contained an active component(s) with T-independent B-cell mitogenic effect.

Infect Immun, 1994 Sep, 62(9), 3801 - 7
Purification and partial biochemical characterization of a Mycoplasma fermentans-derived substance that activates macrophages to release nitric oxide, tumor necrosis factor, and interleukin-6; Muhlradt PF et al.; Mycoplasmal products may exert a number of diverse in vitro effects on cells of the immune system . A macrophage-activating substance from Mycoplasma fermentans was described in this laboratory and named mycoplasma-derived high-molecular-weight material (MDHM) . Using synthesis of nitric oxide by peritoneal cells from endotoxin low-responder mice as an assay system, MDHM was purified as follows . After freeze-thawing of M . fermentans, MDHM activity was sedimented with the membrane fraction . Membranes were delipidated with chloroform-methanol, and MDHM activity was extracted with octyl glucoside . Coextracted proteins were degraded by proteinase K . MDHM was further purified by reversed-phase high-pressure liquid chromatography and eluted in one major and one minor peak of activity . Neither carbohydrates nor amino acids were found as constituents . MDHM had the following properties: it partitioned into the phenol phase upon phenol-water extraction and into the Triton phase after extraction with Triton X-114 . MDHM was not inactivated by either phospholipase A2 or triglyceride lipases . However, mild periodate treatment led to a > 95% loss of activity . Also, alkaline hydrolysis at 25 degrees C completely abolished MDHM activity with a half-life of 2 min . MDHM activity was spread out over a wide molecular weight range upon sodium dodecyl sulfate-polyacrylamide gel electrophoresis of membranes, whereas after proteinase treatment MDHM activity migrated close to the front . These features of MDHM, taken together, speak in favor of an amphiphilic molecule with a lipid moiety carrying fatty acids in ester linkage and a polyol moiety of unknown character . MDHM was active in the nanogram-per-milliliter range, activating macrophages to release nitric oxide, interleukin-6, and tumor necrosis factor.

J Anim Sci, 1994 Sep, 72(9), 2464 - 74
Influence of non-fibrous carbohydrate and degradable intake protein on fermentation by ruminal microorganisms in continuous culture; Mansfield HR et al.; Four continuous culture fermenters were used in a 4 x 4 Latin square design to evaluate the effects of dietary non-fibrous carbohydrate (NFC) and ruminally degradable intake protein (DIP) on fermentation by ruminal microorganisms . Four diets, arranged in a 2 x 2 factorial, were formulated to contain either 25 or 40% NFC and 50 or 70% of dietary CP as DIP . Dietary DM contained 32% corn silage, 20% alfalfa-grass hay, and 48% concentrate . Solvent-extracted or lignosulfonate-treated soybean meal were used to alter DIP and contributed 40% of dietary CP . Corn or soybean hulls were included at 28% of dietary DM to alter NFC levels . Percentage of true OM digestion was similar (P > .05) among diets but NDF and total nonstructural carbohydrate digestion were inversely related depending on NFC content of the diet . Amylolytic bacterial concentrations (cells/milliliter) were lower (P = .03) in fermenters supplied with 25% NFC diets, resulting in less (P = .0001) total nonstructural carbohydrate digestion . Cellulolytic concentrations were similar (P > .05) among diets despite an increase (P = .002) in NDF digestion with 25% NFC diets . Total viable bacterial concentrations tended to decrease (P = .11) with 50% DIP diets, inducing a decline (P = .03) in total VFA production (millimoles/day) . Reduced degradation of CP in 50% DIP diets (P = .008) increased outflow of total amino acid (P = .07) and individual outflows (P < .05) of glutamic acid, aspartic acid, arginine, histidine, and lysine . Few interactions occurred for the parameters measured despite the controlled nature of the fermentation in the current experiment . The preponderance of significant main effects illustrates that ruminal fermentation may not be improved by synchronization of energy and N release but may more likely be limited by either energy or N alone.

Eur J Clin Nutr, 1994 Sep, 48(9), 617 - 24
Digestibility of carbohydrates from rice-, oat- and wheat-based ready-to-eat breakfast cereals in children; Brighenti F et al.; OBJECTIVE: To study the effect of the presence and quality of dietary fibre in ready-to-eat (RTE) breakfast cereals on completeness of carbohydrate digestion in children and on starch susceptibility to alpha-amylase in vitro . DESIGN: A controlled intervention study . SUBJECTS: Eight 3-8-year-old healthy children . INTERVENTIONS: Completeness of digestion was evaluated by assessing the amount of carbohydrates apparently fermented into the colon using the breath-H2 technique after consumption in random order, of five breakfast tests containing boiled rice (either alone or supplemented with 3 g of lactulose) as reference food, or RTE cereals based on rice (low-fibre), wheat (high insoluble fibre) and oats (high-soluble fibre) . The potential glycaemic impact of the products was estimated in vitro by assessing starch susceptibility to alpha-amylolysis using an enzymatic-dialysis method . RESULTS: Compared to boiled rice and to rice-based RTE cereal, wheat- and oat-based RTE cereals both significantly (P < 0.05) increased the amount of apparently fermented carbohydrates (+1.1 +/- 1.7% of total breakfast carbohydrate fermented for rice, +5.6 +/- 0.9% for wheat and +9.4 +/- 3.7% for oats; mean +/- SEM), calculated using the excess H2 in breath after lactulose as standard . All products showed similar in vitro digestibility, resulting in estimated glycaemic indexes of 117.5 (24.0) for rice, and 105.7 (14.1) for oats-based, 128.4 (17.6) for wheat-based, and 129.8 (16.6) {mean 95% CI)} for rice-based RTE cereals . CONCLUSIONS: Results suggest that the presence of fibre in RTE breakfast cereals, in particular soluble fibre, increases colonic fermentation in children whereas it seems not to affect glucose availability.

J Appl Bacteriol, 1994 Sep, 77(3), 264 - 70
Protease production by Streptomyces thermovulgaris grown on rapemeal-derived media; Yeoman KH et al.; A range of actinomycete species was tested for their ability to grow on particulate and particle-free rapeseed meal-derived media . Streptomycetes grew on both types of medium and produced a number of extracellular enzymes . Highest activities of protease were produced by Streptomyces thermovulgaris and reflected the high available protein content of rapemeal . Enzyme production and growth were analysed in fermentor-grown batch cultures of S . thermovulgaris using the particle-free rapemeal broth termed medium B . Growth was biphasic and the majority of the protease was produced during the second slower phase . Analysis of the protease as azocaseinase activity revealed a high degree of thermostability in the presence of calcium such that approximately 20% of the activity remained after incubation at 70 degrees C for 24 h . Gel filtration suggested that S . thermovulgaris synthesized more than one kind of protease and this was confirmed by using specific peptide substrates and inhibitors which revealed the presence of distinct serine and metallo-type enzymes.

Analyst, 1994 Sep, 119(9), 2037 - 41
Biogenic amines in table olives . Analysis by high-performance liquid chromatography; Hornero-Mendez D et al.; Biogenic amines in fermented vegetables have scarcely been studied . Available data show that in table olives and fermented cucumbers their presence is rare and any determinations made have been restricted mainly to histamine . However, some microorganisms, especially those related to spoilage, found in the fermentation brines of such products may have amino acid decarboxylase activity and give rise to biogenic amines by unusual processes . A method for the simultaneous determination of eight biogenic amines (tryptamine, beta-phenylethylamine, putrescine, cadaverine, histamine, tyramine, spermidine, and spermine) has been developed to study their occurrence in fermented vegetables in more detail . The method consists of extraction of the amines from olive paste with 5% m/v trichloracetic acid and successive transfers into water-saturated n-BuOH and 0.1 mol l-1 HCl . An aliquot of this mixture is dried and derivatized with dansyl chloride . The dansyl derivatives are then analysed by high-performance liquid chromatography . Special emphasis has been given to optimization of the n-BuOH and 0.1 mol l-1 HCl extractions and to the derivatization conditions . By applying this method to the analysis of spoilt olives, the presence of some biogenic amines has been demonstrated . Thus a new method for monitoring the presence of biogenic amines during the fermentation of olives and for detecting anomalous fermentations is envisaged.

Epidemiol Mikrobiol Imunol, 1994 Sep, 43(3), 107 - 10
{Use of the NEFERMtest apparatus for identification of gram-negative non-fermenting rods occurring in clinical material}; Rojickova R et al.; The new identification system NEFERMtest (fy Lachema, Brno) was evaluated . The identification efficacy of two systems, Index (fy Lachema) and computer programme (Czech Collection of Microorganisms, Brno) was compared . A total of 222 bacterial strains including 41 species occurring in clinical material were tested . The Index identified correctly to the species level 38 strains (27.1%) of the reference strains and 32.9% of 82 clinical isolates . The identification efficacy of the computer programme TNW was 48.6% for the reference strains, 95.1% for the strains obtained from clinical specimens.

J Antibiot (Tokyo), 1994 Sep, 47(9), 982 - 91
Eurystatins A and B, new prolyl endopeptidase inhibitors . III . Fermentation and controlled biosynthesis of eurystatin analogs by Streptomyces eurythermus; Suzuki K et al.; Accurate and precise component analysis of eurystatin analogs in fermentation broth was devised by HPLC methods with and without 2,4-dinitrophenylhydrazonation . Detailed optimization of fermentation conditions and strain improvement by HPLC analysis significantly increased the eurystatin productivity of Streptomyces eurythermus . Chemically defined fermentation media which produced eurystatins A and B at fermentation yields comparable to complex media were elaborated for radio-isotope fermentation studies and controlled biosynthesis . Radio-isotope incorporation study using 14C-labeled amino acids in chemically defined medium demonstrated that L-leucine and L-ornithine were the direct precursors for the L-leucine and L-ornithine moieties of eurystatins A and B, respectively . Based on this finding, L-valine and L-isoleucine were supplemented to the growing culture of S . eurythermus in chemically defined medium, which resulted in the controlled biosynthesis of new eurystatin analogs named eurystatins C, D, E and F.

Plant Foods Hum Nutr, 1994 Sep, 46(2), 157 - 65
Nutritive value of baobab milk (gubdi) and mixtures of baobab (Adansonia digitata L.) and hungry rice, acha (Digitaria exilis) flours; Obizoba IC et al.; The baobab milk and fermented baobab/acha flour mixtures were analyzed chemically for their proximate, ascorbate, mineral and antinutrient composition . The dry pulp scraped from baobab fruits was kneaded, made into solution, extracted through cheese-cloth and stored frozen until analyzed . The acha and baobab grains were cleaned, fermented for 24 to 120 hours, dried and hammermilled into fine flours . The unfermented flours served as controls . The standard assay methods of AOAC were selected for use for the analysis of the nutrients and the antinutrients . The mixtures were composed of 70% acha and 30% baobab flours (70:30 protein basis) . The baobab milk contained more protein (1.5%) and minerals (Fe, 17.8 mg; Ca 134.2 mg) than those of human milk (protein, 1.3%, Fe, 0.2 mg, Ca 30 mg) and cow milk (Fe, 0.1 mg; Ca 1.20 mg) and most leading national commercial infant formulas e.g . cerelac (Fe, 10.0 mg) . The composite flours contained more nutrients than the baobab or the acha flour alone . The BF96 had greater advantage over other BF flours as a supplement to acha . The mixtures are within the reach of lower income group and can be incorporated into their diets.

Plant Foods Hum Nutr, 1994 Sep, 46(2), 109 - 16
Traditional production and chemical composition of Ndaleyi, a Nigerian fermented pearl millet food; Nkama I et al.; Ndaleyi, a fermented, sun dried agglomerated powder produced from pearl millet or sorghum is one of the most popular foods consumed in Nigeria, mostly by the Kanuri people of Borno State . Its traditional production is described . The mean yields of ndaleyi (mainly starch), chir ('millet gluten') and 'bran' (overtail or bina) were 30.6, 22.5 and 21.5%, respectively . A mean yield loss of 20% was observed . Chemical analysis revealed that chir and 'bran' have higher protein, fat and ash contents than ndaleyi . The titratable acidities (as percent lactic acid) of ndaleyi and chir were 0.9 and 0.3, while their pH values were 3.3 and 3.5, respectively.

Scand J Gastroenterol, 1994 Sep, 29(9), 826 - 32
Carbohydrate malabsorption: quantification by methane and hydrogen breath tests; Rumessen JJ et al.; BACKGROUND: Previous studies in small series of healthy adults have suggested that parallel measurement of hydrogen and methane resulting from gut fermentation may improve the precision of quantitative estimates of carbohydrate malabsorption . Systematic, controlled studies of the role of simultaneous hydrogen and methane measurements using end-expiratory breath test techniques are not available . METHODS: We studied seven healthy, adult methane and hydrogen producers and seven methane non-producers by means of end-expiratory breath test techniques . Breath gas concentrations and gastrointestinal symptoms were recorded at intervals for 12h after ingestion of 10, 20 and 30 g lactulose . RESULTS: In the seven methane producers the excretion pattern was highly variable; the integrated methane responses were disproportional and not reliably reproducible . However, quantitative estimates of carbohydrate malabsorption on the basis of individual areas under the methane and hydrogen excretion curves (AUCs) tended to improve in methane producers after ingestion of 20 g lactulose by simple addition of AUCs of methane to the AUCs of the hydrogen curves . Estimates were no more precise in methane producers than similar estimates in non-producers . Gastrointestinal symptoms increased significantly with increasing lactulose dose; correlation with total hydrogen and methane excretion was weak . CONCLUSIONS: Our study suggests that in methane producers, simple addition of methane and hydrogen excretion improves the precision of semiquantitative measurements of carbohydrate malabsorption . The status of methane production should, therefore, be known to interpret breath tests semiquantitatively . The weak correlation between hydrogen and methane excretion and gas-related abdominal complaints suggests that other factors than net production of these gases may be responsible for the symptoms.

Exp Physiol, 1994 Sep, 79(5), 823 - 30
Indirect measurement of saliva secretion in sheep fed diets of different structures and the effect of such diets on ruminal fluid kinetics and fermentation pattern; Duric M et al.; Four Suffolk x Dorset sheep were allocated in a 4 x 4 Latin square design and received a hay-barley-molasses diet in one of four different physical structures: (1) pelleted; (2) pelleted:chopped (60:40); (3) chopped:pelleted (60:40); or (4) chopped . The animals were penned individually and the diet was restricted to provide 20 g of dry matter (DM) per kilogram live weight daily . The effects of the diets on rumen fluid kinetics, fermentation pattern and microbial nitrogen (MN) supply were examined . Saliva secretion was estimated using an indirect method based on water balance in the rumen . When the animals were fed the chopped diet, the salivation rate, rumen fluid volume and rumen liquid outflow were all increased significantly (P < 0.05 to P < 0.01) . No consistent effect of dietary structure on rumen fluid dilution rate, purine derivative (PD) excretion or MN supply was observed . Dietary structure had no effect on the rumen fermentation pattern, digestibility of DM or nitrogen.

J Dairy Sci, 1994 Sep, 77(9), 2821 - 36
Metabolic relationships in the supply of nutrients for milk protein synthesis: integrative modeling; Baldwin RL et al.; The objective of research under the NC-185 regional project is to identify the critical chemical transformations in the rumen, digestive tract, gastrointestinal and splanchnic tissues, and adipose and mammary tissues that define patterns of nutrient utilization in lactating dairy cows . This objective includes research on differences in fermentation, digestion, absorption, and tissue utilization of nutrients in sufficiently different situations to permit estimation of parameters defining various nutrient interconversions . The regional project is utilizing dynamic, mechanistic models of metabolism as tools for integrative analyses of experimental data generated by the group . During the early phases of the project emphasized herein, primary emphasis was on development of models of adipose tissue, mammary gland, liver, rumen, and whole animal metabolism . Serious inadequacies exist in the detail and scope of knowledge of rates of chemical transformations across the wide range of milk yields and nutrient intakes found in production situations . Current knowledge, as described in the various equations and parameters in the models, is presented and discussed . Some characteristics of the current models are illustrated, and methods to utilize the models to identify important experiments are discussed . More cooperative efforts are necessary, including experimental designs that focus on quantification of relationships between input and output, physiological mechanisms that alter patterns of nutrient utilization in lactating dairy cows, and yield estimates of the parameters describing the pre- and postabsorptive uses of feed nutrients.

J Dairy Sci, 1994 Sep, 77(9), 2762 - 86
Evaluation of chemical and physical properties of feeds that affect protein metabolism in the rumen; Stern MD et al.; The goal of the NC-185 Cooperative Regional Research Project is to provide the information needed to improve the nutrition and feeding of dairy cattle, a major factor determining composition of milk and cost of milk yield . Emphasis is placed on understanding how energy and protein nutrition of lactating cows can be manipulated to increase the quantity and improve the profile of AA passing to the small intestine and to improve yield of milk and milk protein . To achieve this goal, one of the major objectives of this project has been to evaluate quantitatively the chemical and physical properties of protein and energy sources that determine AA availability to lactating cows . Reliable measurements of microbial protein synthesis and protein degradation in the rumen are critical in the evaluation process . Therefore, one of the ongoing areas of investigation of this research project has been to determine the most appropriate methods for estimating microbial protein synthesis and dietary protein degradation in the rumen . Other areas have been investigated, using continuous culture fermenters and ruminally and duodenally cannulated cows, including factors that alter microbial metabolism of N in the rumen and subsequently protein supply to the small intestine, such as sources of carbohydrate, protein, and fat and interrelationships of protein and carbohydrate . Findings of the NC-185 Cooperative Regional Research Project Committee and other investigators are summarized in this review.

Antimicrob Agents Chemother, 1994 Sep, 38(9), 2008 - 13
Assays to detect and characterize human immunodeficiency virus type 1 (HIV-1) receptor antagonists, compounds that inhibit binding of the HIV-1 surface glycoprotein, gp120, to the CD4 receptor on human T lymphocytes; Clancy J et al.; Human immunodeficiency virus type 1 infects human helper T lymphocytes by an interaction between gp120, the viral coat protein, and the T-cell receptor CD4 . Two microtiter-based immunoassays, an enzyme-linked immunosorbent assay (ELISA) and a particle concentration fluorescence assay, were developed to measure gp120-CD4 binding and were then used to screen a variety of compounds for the inhibition of this interaction . Additional protocols, called "consumption assays," were defined to distinguish inhibitors which functioned by sequestering either gp120 or CD4 to prevent the final effective bimolecular interaction . Monoclonal antibodies of defined specificity and compounds known from other published studies to inhibit gp120-CD4 binding were tested in an attempt to validate the assays used in the study . Once the capacity of these assays to detect known gp120-CD4 inhibitors was confirmed, they were used to screen synthetic agents and fermentation broths for novel compounds that might be used as human immunodeficiency virus receptor antagonists . A 2,4-diaminoquinazoline, CP-101,816-1, was found to inhibit this interaction (50% inhibitory concentration in ELISA, 32.5 micrograms/ml) and to interact more strongly with CD4 than with gp120 in the consumption assays . The identification of a novel inhibitor, a 2,4-diaminoquinazoline, confirmed that such assays are useful for the detection of human immunodeficiency virus type 1 receptor antagonists.

Biotechnol Prog, 1994 Sep-Oct, 10(5), 555 - 60
Cost analysis of ethanol production from willow using recombinant Escherichia coli; von Sivers M et al.; This study comprises a technical and economic analysis of the production of fuel ethanol by fermentation of a pentose-rich hydrolysate with recombinant Escherichia coli, strain KO11 . Hydrolysate from steam-pretreated willow was used as raw material in calculations regarding the fermentation . The calculations were based on a feed capacity of 10 metric tons of dry willow per hour to the pretreatment stage, providing 35 metric tons of hydrolysate per hour, consisting of 45 g of sugars/L, to the pentose fermentation plant . A detoxification step was included, since the hydrolysate has been shown to have an inhibitory effect on the E . coli KO11 . The technical data used in the calculations were based on a kinetic fermentation model, which was developed from laboratory-scale experiments in a previous study . The economic analysis predicted an ethanol production cost of 48/L in the pentose fermentation plant, indicating potentially good economy . The detoxification cost constitutes 22% of this cost . Sensitivity analyses revealed that if the concentration of sugars in the feed to the fermentation was decreased by 40% to 27 g/L, the ethanol production cost was increased to 54/L . The production cost was increased to 50/L ethanol if the cell mass was recirculated to the fermentation stage 5 times instead of 20.

Trends Biotechnol, 1994 Sep, 12(9), 346 - 52
Eosinophilia-myalgia syndrome and tryptophan production: a cautionary tale; Mayeno AN et al.; An epidemic of a new disease, termed eosinophilia-myalgia syndrome, occurred in the USA in 1989 . This syndrome was linked to the consumption of L-tryptophan manufactured by a single company utilizing a fermentation process . All the findings indicate that the illness was probably triggered by an impurity formed when the manufacturing conditions were modified . This outbreak highlights the need for close monitoring of the chemical purity of biotechnology-derived products, and for rigorous testing of such products following any significant changes to the manufacturing process.

Antibiot Khimioter, 1994 Sep-Oct, 39(9-10), 6 - 11
{Biogenesis of 6-aminopenicillanic acid (6-APA) and penicillin in Penicillium chrysogenum: effect of the biocatalyst chrysin}; Bosnic P et al.; The investigations were concerned with the examination of the effect of chrysin, a biocatalyst on the 6-APA and penicillin biogenesis in Penicillium chrysogenum (Thom), Panlabs P-5 strain . Chrysin, a natural plant biocatalyst was used to increase the large scale production of penicillin . The experiments were conducted on chemically defined media under conditions determined for this strain in shake flask fermentations . The production of 6-APA and penicillin G was checked and confirmed by HPLC . The level of free 6-APA in the germinating culture increased 12 hours after the inoculation of the P . chrysogenum conidiospores . With the addition of chrysin to the germinating culture the biogenesis of penicillin started in 14 hours but in the experiments without the chrysin addition it was observed 21 hours after the conidiospore inoculation . The origin of free 6-APA in the fermentation broth could be explained solely by the involvement of an independent metabolic pathway of the 6-APA and penicillin biogenesis i.e . N-acylation of free 6-APA . In the fermentation broth of P . chrysogenum it is necessary to distinguish between the primary 6-APA which is a product of the biosynthesis via L-cystine/D-valine and the secondary 6-APA which originates from isopenicillin N.

Z Naturforsch {C}, 1994 Sep-Oct, 49(9-10), 561 - 70
Hyphodontal, a new antifungal inhibitor of reverse transcriptases from Hyphodontia sp . (Corticiaceae, Basidiomycetes); Erkel G et al.; In a search for inhibitors of RNA-directed DNA polymerases a new isolactarane sesquiterpenoid, hyphodontal (1), was isolated from fermentations of a Canadian Hyphodontia species . Its structure was elucidated by spectroscopic methods . Hyphodontal strongly inhibits the growth of several yeasts and is a non-competitive inhibitor of avian myeloblastosis virus (Ki 346 microM) and Moloney murine leukemia virus (Ki 112 microM) reverse transcriptases . In addition, cytotoxic and antifungal activities were observed.

Infect Immun, 1994 Sep, 62(9), 3793 - 800
A 48-kilodalton Mycoplasma fermentans membrane protein induces cytokine secretion by human monocytes; Kostyal DA et al.; Mycoplasma fermentans is one of several Mycoplasma species that have been reported to stimulate tumor necrosis factor (TNF) secretion from monocytes . This activity has been associated primarily with the mycoplasma membrane fraction . In this article, we have characterized a membrane protein that stimulates TNF and interleukin 1 beta secretion . The TNF-releasing activity partitioned into the Triton X-114 detergent phase, suggesting that the molecules is hydrophobic . The secretion of TNF is elevated in the presence of serum, which suggests that a serum component may play a role in the interaction between this mycoplasma protein and monocytes . Treatment of monocytes with monoclonal anti-CD14 antibody had no effect on the levels of TNF-releasing activity . By using the monocyte Western blot (immunoblot) technique, we have determined the molecular mass of the active molecule to be 48 kDa . This molecule appears to be distinct from the recently described family of variable lipoproteins of M . fermentans . Mycoplasma particulate material treated with proteinase K lost all inducing activity, whereas lipoprotein lipase-treated samples retained some level of activity.

Hindustan Antibiot Bull, 1994 Aug-Nov, 36(3-4), 164 - 72
Expanded bed chromatography and radial flow column chromatography: the approaches for adsorption chromatography of biomolecules on industrial scale; Ambedkar SS et al.; Adsorption of proteins directly from unclarified feed-stocks, has gained importance in the recovery of biomolecules on Industrial scale . Adsorption in expanded beds and radial flow gives significantly better results compared to conventional column chromatography methods for downstream processing of variety of proteins from particulate-containing feed-stocks, such as fermentation broths and cells extracts . The simple operation of these techniques reduces the complexity of downstream processing by eliminating steps such as filtration, centrifugation and concentration . One step purification, with simple equipment, these techniques enable to recover pure protein with 95% yield in biotechnological industry . The principles, operating procedures, adsorbents and applications of these techniques are discussed.

J Nutr, 1994 Aug, 124(8 Suppl), 1377S - 1382S
The role of dietary fats in efficiency of ruminants; Palmquist DL; Fat increases energetic efficiency in lactating cows by increasing total energy intake, by generating ATP more efficiently (ATP/unit energy expended) than volatile fatty acids or protein, by direct incorporation into product, and by promoting nutrient partition toward milk production . Factors that limit utilization of large amounts of fat by ruminants include inhibitory effects on ruminal fermentation, lower intestinal absorption at high intake, low contribution to total oxidation of nutrients, and sensitivity to nutrient imbalance, causing reduced energy intake . Research has resolved many problems associated with effects on ruminal fermentation; research in the future may improve fat digestibility and reduce limits of oxidation . Effect of high fat on regulation of feed intake has received little attention.

Curr Genet, 1994 Aug, 26(2), 166 - 71
Genetic evidence for independence between fermentative metabolism (ethanol accumulation) and yeast-cell development in the dimorphic fungus Mucor rouxii; Torres-Guzman JC et al.; Three allyl-alcohol-resistant mutants were isolated in the dimorphic fungus Mucor rouxii and characterized with regard to their alcohol dehydrogenase (ADH) activity in vitro and in vivo as well as their ability to execute the morphological alternatives of dimorphism under different environmental stimuli, either in the absence or in the presence of oxygen . These studies indicated that fermentation and yeast-cell development are independent events and that ADH activity is essential for growth of the fungus in the absence of oxygen . Heterokaryon construction and analysis indicated that in the three mutant strains the corresponding genetic alterations are recessive nuclear mutations which behave as allelic in complementation tests.

Yeast, 1994 Aug, 10(8), 1049 - 64
Activation of trehalase during growth induction by nitrogen sources in the yeast Saccharomyces cerevisiae depends on the free catalytic subunits of cAMP-dependent protein kinase, but not on functional Ras proteins; Durnez P et al.; Addition of a nitrogen-source to glucose-repressed, nitrogen-starved G0 cells of the yeast Saccharomyces cerevisiae in the presence of a fermentable carbon source induces growth and causes within a few minutes a five-fold, protein-synthesis-independent increase in the activity of trehalase . Nitrogen-activated trehalase could be deactivated in vitro by alkaline phosphatase treatment, supporting the idea that the activation is triggered by phosphorylation . Yeast strains containing only one of the three TPK genes (which encode the catalytic subunit of cAMP-dependent protein kinase) showed different degrees of nitrogen-induced trehalase activation . The order of effectiveness was different from that previously reported for glucose-induced activation of trehalase in glucose-depressed yeast cells . Further reduction of TPK-encoded catalytic subunit activity by partially inactivating point mutations in the remaining TPK gene further diminished nitrogen-induced trehalase activation, while deletion of the BCY1 gene (which encodes the regulatory subunit) in the same strains resulted in an increase in the extent of activation . Deletion of the RAS genes in such a tpkw1 bcy1 strain had no effect . These results are consistent with mediation of nitrogen-induced trehalase activation by the free catalytic subunits alone . They support our previous conclusion that cAMP does not act as second messenger in this nitrogen-induced activation process and our suggestion that a novel nitrogen-induced signaling pathway integrates with the cAMP pathway at the level of the free catalytic subunits of protein kinase A . Western blot experiments showed that the differences in the extent of trehalase activation were not due to differences in trehalase expression . On the other hand, we cannot completely exclude that protein kinase A influences the nitrogen-induced activation mechanism itself rather than acting directly on trehalase . However, any such alternative explanation requires the existence of an additional, yet unknown, mechanism for activation of trehalase besides the well-established regulation by protein kinase A.

J Clin Microbiol, 1994 Aug, 32(8), 1918 - 22
Recognition of Dermabacter hominis, formerly CDC fermentative coryneform group 3 and group 5, as a potential human pathogen; Gruner E et al.; Thirty strains of fermentative coryneform-like bacteria designated CDC fermentative coryneform group 3 and coryneform group 5 were compared biochemically by cellular fatty acid analysis and by DNA relatedness with the type strain of Dermabacter hominis, ATCC 49369 . DNA from 22 strains of both CDC groups showed 69 to 96% relatedness (hydroxyapatite method) to labeled DNA from ATCC 49369 and to DNA from CDC group 3 strain G4964, and the strains are considered to belong to D . hominis . The remaining eight strains were genetically but not phenotypically differentiable from D . hominis . They were genetically heterogeneous, but hybridization results indicated that they probably belong to the genus Dermabacter . Thirteen of the 22 D . hominis strains and all 8 of the other Dermabacter strains had been isolated from blood, which indicates the pathogenic potential of this species and genus.

J Anim Sci, 1994 Aug, 72(8), 2158 - 70
Influence of yeast culture supplementation and advancing season on steers grazing mixed-grass prairie in the northern Great Plains: II . Ruminal fermentation, site of digestion, and microbial efficiency; Olson KC et al.; Twelve ruminally and duodenally cannulated beef steers (initial BW 368 +/- 25.3 kg) and four ruminally cannulated beef heifers (initial BW 559 +/- 79.5 kg) were used to evaluate the effects of yeast culture (YC) and advancing season on ruminal fermentation, microbial protein synthesis, ruminal fluid kinetics, and site of digestion . Treatments were control and YC supplementation (28.4 g.steer-1.d-1 dosed ruminally) . Steers grazed from late June to early November 1991 on mixed-grass prairie . Ruminal pH decreased (P < .10) from late July to early October . Fluid dilution rate decreased (P < .10) as the grazing season advanced, whereas ruminal fluid volume and flow rate increased (P < .10) from late July to early October . Ruminal ammonia concentration (milligrams/deciliter) was lower (P < .10) during late July and late August than during late June and early October at 4, 8, 12, and 16 h after sunrise in YC-supplemented steers . Molar proportions of propionate and butyrate were greater (P < .10) in control than in YC-supplemented steers at 0, 4, 12, and 24 h and 0, 4, and 12 h after sunrise, respectively, during late July . Acetate (mol/100 mol) was greater (P < .10) during late July and late August than in late June and early October for YC-supplemented steers at 0, 4, and 8 h after sunrise . True ruminal OM digestion was greatest (P < .10) in late June, intermediate in late July and late August, and least in early October . Supplementation with YC increased (P < .04) true ruminal OM digestion in late June and late July . Steers receiving YC had greater (P < .07) duodenal bacterial N flow in late July . These data indicate that yeast culture supplementation can increase true OM digestibility early in the grazing season . Advancing season seems to result in increased ruminal fluid volume, lower true ruminal OM digestion, and greater microbial efficiency.

J Anim Sci, 1994 Aug, 72(8), 2113 - 23
Supplemental protein for beef cattle grazing dormant intermediate wheatgrass pasture: effects on nutrient quality, forage intake, digesta kinetics, grazing behavior, ruminal fermentation, and digestion; Hess BW et al.; Sixteen ruminally cannulated yearling beef cattle (British x British; average BW = 295 +/- 25 kg; three steers and one heifer per treatment) grazing dormant intermediate wheatgrass (Thinopyrum intermedium Host) were allotted to four treatments: 1) no supplement (CON); 2) alfalfa hay (ALF; .52% of BW); 3) cottonseed meal (CSM; .22% of BW); and 4) corn gluten meal-wheat bran feed (CGMWBF; .36% of BW) . Supplements were formulated (DM basis) so that intakes were isonitrogenous and were provided once daily (0700) . Sampling periods were in February (FEB; .96% N in masticate), March (MAR; 1.06% N in masticate), and April (APR; 1.12% N in masticate) following an initial 21-d adaptation period . Daily grazing time was 1.1 to 1.5 h longer (P < .05) for CON cattle than for supplemented cattle . Forage OM intake (OMI) was not altered (P > .15) by supplemental protein; however, total OMI was greater (P < .04) for supplemented than for unsupplemented cattle . Harvesting efficiency (grams of OM intake-kilogram of BW-1.minute spent grazing-1) was greater (P < .05) for cattle fed CSM than for those fed CGF or CON; cattle fed ALF were intermediate in harvesting efficiency . Ruminal fluid kinetics, in situ rate and extent of NDF digestion, and total VFA concentration were not influenced (P > .10) by type of supplemental protein . Ruminal NH3 N concentration exhibited a treatment x sampling time interaction (P < .05) . Type of protein supplement did not seem to affect most digestion measures; however, harvesting efficiency was influenced by supplement type.

J Indian Med Assoc, 1994 Aug, 92(8), 255 - 6
Rapid diagnosis of anaerobic gram-positive cocci by salt tolerance; Chatterjee BD et al.; The maximum salt tolerance was 2.5% in cases of Peptostreptococcus anaerobius and Peptococcus prevotii, 3% in Ruminococcus albus, 4% in Acidaminococcus fermentans, Peptococcus niger and Megasphaera elsdenii and 5% in Peptococcus magnus . The biochemical tests being largely inactive and time consuming the findings of salt tolerance if combined with those of morphological data provide clue to the rapid identification of Gram-positive anaerobic cocci.

J Dairy Sci, 1994 Aug, 77(8), 2382 - 92
Influence of pH and rapidly fermentable carbohydrate on mineral release in and flow from the rumen; Emanuele SM et al.; Objectives for this study were to determine the effect of energy supplementation on mineral release in and outflow from the rumen, independent of pH . Nonlactating Holstein cattle with ruminal cannulas were limit-fed chopped alfalfa hay with or without energy supplement . Treatments were 1) control, alfalfa plus ruminal infusion of 3 L/d of distilled water; 2) acid, alfalfa plus infusion of 3 L/d of 1N HCl; 3) energy supplement, alfalfa and ground corn plus infusion of 3 L/d of distilled water; and 4) buffered energy supplement, alfalfa, and ground corn plus infusion of 3 L/d of distilled water containing 90 g of NaHCO3 . Macromineral intake was standardized across treatments by adjustment of infusion solutions with inorganic mineral sources . Dry matter consumed was 5 kg/d on treatments 1 and 2 and 8.4 kg/d on treatments 3 and 4 . Mean ruminal pH was 6.8, 6.1, 5.6, and 6.2 for treatments 1 through 4, respectively . Ruminal pH was more significant than energy supplementation in dispersion of Ca, Mg, and P in ruminal digesta . Only 1, 17, and 27% of dietary K, Mg, and P flowed with solids from the rumen, but 52% of Ca and 41% of Cu remained with the solid phase.

J Antibiot (Tokyo), 1994 Aug, 47(8), 901 - 8
Glycothiohexide alpha, a novel antibiotic produced by "Sebekia" sp., LL-14E605 . III . Structural elucidation; Northcote PT et al.; The chemical structure of a novel thiopeptide antibiotic, glycothiohexide alpha (1), isolated from the fermentation broth of a "Sebekia" species was determined based on extensive 2D NMR studies, as well as, IR, UV, and mass spectral data . The chemical structure of glycothiohexide alpha is closely related to nosiheptide (3) and antibiotic S-54832A.

J Antibiot (Tokyo), 1994 Aug, 47(8), 894 - 900
Glycothiohexide alpha, a novel antibiotic produced by "Sebekia" sp., LL-14E605 . II . Isolation and physical-chemical characterization; Northcote PT et al.; Glycothiohexide alpha was recovered from the fermentation broth of a "Sebekia" sp . by mixed solvent extraction, selective precipitation and adsorption chromatography on Diaion HP-20 . The amount of glycothiohexide alpha present in the crude preparation was enriched by photolysis . Purification of glycothiohexide alpha was accomplished by repetitive countercurrent chromatography.

J Antibiot (Tokyo), 1994 Aug, 47(8), 870 - 4
Dorrigocins: novel antifungal antibiotics that change the morphology of ras-transformed NIH/3T3 cells to that of normal cells . II . Isolation and elucidation of structures; Hochlowski JE et al.; Two novel antifungal antibiotics, named dorrigocin A and B have been isolated from the fermentation broth and mycelium of Streptomyces platensis subsp . rosaceus . These closely related compounds were separated from one another by countercurrent chromatography on an Ito coil planet centrifuge . The structures of the dorrigocins were determined by NMR and IR spectroscopy and mass spectrometry . Each is a putative propionate-acetate derived straight chain fatty acid terminating in cycloheximide . The dorrigocins differ from one another only in their oxidation pattern.

J Antibiot (Tokyo), 1994 Aug, 47(8), 862 - 9
Dorrigocins: novel antifungal antibiotics that change the morphology of ras-transformed NIH/3T3 cells to that of normal cells . I . Taxonomy of the producing organism, fermentation and biological activity; Karwowski JP et al.; The dorrigocins are new secondary metabolites produced by submerged fermentation of a streptomycete which was isolated from a soil sample collected in Australia . The dorrigocins show moderate antifungal activity and reverse the morphology of ras-transformed NIH/3T3 cells from a transformed phenotype to a normal one . The producing culture was identified as Streptomyces platensis subsp . rosaceus strain AB1981F-75.

FEMS Microbiol Rev, 1994 Aug, 14(4), 325 - 32
Improvement of heavy metal biosorption by mycelial dead biomasses (Rhizopus arrhizus, Mucor miehei and Penicillium chrysogenum): pH control and cationic activation; Fourest E et al.; Fungal mycelial by-products from fermentation industries present a considerable affinity for soluble metal ions (e.g . Zn, Cd, Ni, Pb, Cr, Ag) and could be used in biosorption processes for purification of contaminated effluents . In this work the influence of pH on sorption parameters is characterized by measuring the isotherms of five heavy metals (Ni, Zn, Cd, Ag and Pb) with Rhizopus arrhizus biomass under pH-controlled conditions . The maximum sorption capacity for lead was observed at pH 7.0 (200 mg g-1), while silver uptake was weakly affected . The stability of metal-biosorbent complexes is regularly enhanced by pH neutralization, except for lead . A transition in sorption mechanism was observed above pH 6.0 . In addition, comparison of various industrial fungal biomasses (R . arrhizus, Mucor miehei and Penicillium chrysogenum) indicated important variations in zinc-binding and buffering properties (0.24, 0.08 and 0.05 mmol g-1, respectively) . Without control, the equilibrium pH (5.8, 3.9 and 4.0) is shown to be related to the initial calcium content of the biosorbent . pH neutralization during metal adsorption increases zinc sorption in all fungi (0.57, 0.52 and 0.33 mmol g-1) but an improvement was also obtained (0.34, 0.33 and 0.10 mmol g-1) by calcium saturation of the biomass before heavy metal accumulation . Breakthrough curves of fixed bed biosorbent columns demonstrated the capacity of the biosorbent process to purify zinc and lead solutions in continuous-flow systems, and confirmed the necessity for cationic activation of the biosorbent before contact with the heavy-metal solution.

FEMS Microbiol Rev, 1994 Aug, 14(4), 291 - 302
Advances in biosorption of metals: selection of biomass types; Volesky B; Within the past decade, the potential of metal biosorption has been well established . For economic reasons, of particular interest are abundant biomass types either generated as a waste by-product of large-scale industrial fermentations or certain metal-binding algae found in large quantities in the sea . Some of these high metal-sorbing biomass types serve as a basis for newly developed metal biosorption processes foreseen particularly as a very competitive means for detoxification of metal-bearing industrial effluents . Ions of lead and cadmium, for instance, have been found to be bound very efficiently from very dilute solutions by the dried biomass of some ubiquitous brown marine algae such as Ascophyllum and Sargassum which accumulate more than 30% of biomass dry weight in the metal . Mycelia of industrially steroid-transforming fungi Rhizopus and Absidia are excellent biosorbents for lead, cadmium, copper, zinc, and uranium, binding also other heavy metals up to 25% of the biomass dry weight . The common yeast Saccharomyces cerevisiae is a 'mediocre' metal biosorbent . Construction of biosorption isotherm curves serves as a basic technique assisting in evaluation of the metal uptake by different biosorbents . The methodology is based on batch equilibrium sorption experiments extensively used for screening and quantitative comparison of new biosorbent materials . Experimental methodologies used in the study of biosorption and selected recent research results demonstrate the route to novel biosorbent materials some of which can even be repeatedly regenerated for re-use.

Biotechnol Appl Biochem, 1994 Aug, 20 ( Pt 1), 23 - 33
Enzymic preparation of (3R-cis)-3-(acetyloxy)-4-phenyl-2-azetidinone: a taxol side-chain synthon; Patel RN et al.; A key chiral intermediate {(3R-cis)-3-(acetyloxy)-4-phenyl-2-azetidinone (2)} for the semi-synthesis of paclitaxel (taxol; 5), an anti-cancer compound, was prepared by an enzymic process . The stereoselective enzymic hydrolysis of cis-3-(acetyloxy)-4-phenyl-2-azetidinone (1) to the corresponding (S)-(-)-alcohol (3) was carried out using various lipases . Lipase PS-30 (Pseudomonas cepacia) and BMS (Bristol-Myers Squibb) lipase (Pseudomonas sp . SC13856) catalysed hydrolysis of the undesired enantiomer of racemic compound 1, producing the (S)-(-)-alcohol (3) and the desired (R)-(+)-acetate (2) . Reaction yields of > 96% and optical purities of > 99.5% were obtained . For a very efficient enzyme source (BMS lipase), a lipase fermentation using Pseudomonas sp . SC13856 was developed . In a fed-batch process using soybean oil, the fermentation resulted in 1500 units of extracellular lipase activity/ml . Crude BMS lipase (1.7 kg, containing 140,000 units/g) was recovered from the filtrate by ethanol precipitation . BMS lipase and commercially available lipase PS-30 were independently immobilized on Accurel polypropylene . These immobilized lipases were re-used (ten cycles) without loss of enzyme activity, productivity or optical purity of the product . The enzymic reaction process was scaled up to 75 and 150 litres using immobilized BMS lipase and lipase PS-30 respectively . From the reaction mixture, compound 2 was isolated in 88-90 mol% yield and 99.5% optical purity . A purity of 99.9 (area %) was demonstrated by g.c . for isolated compound 2.

Microb Pathog, 1994 Aug, 17(2), 131 - 5
Detection of Mycoplasma fermentans DNA from lymph nodes of acquired immunodeficiency syndrome patients; Sasaki Y et al.; Biopsy samples from seven patients with acquired immunodeficiency syndrome were screened for Mycoplasma fermentans, M . pneumoniae and M . genitalium infection by the polymerase chain reaction . M . fermentans DNA was detected in four patients . Various tissues were evaluated and the mycoplasma were mainly detected from lymph nodes . Moreover, mycoplasma genus-specific DNA was isolated from peripheral blood mononuclear cells of asymptomatic human immunodeficiency virus(HIV)-infected individuals (two of 31 HIV-infected individuals) . These data suggest that mycoplasma infection in AIDS patients is not uncommon.

Zh Mikrobiol Epidemiol Immunobiol, 1994 Aug-Sep, Suppl 1, 60 - 4
{The use of an amplification test system for detecting persistent mycoplasmas}; Solov'eva SV et al.; A DNA amplification test system for the detection of Mycoplasma fermentans in clinical specimens was developed . The system was used for the analysis of biological specimens obtained from experimentally infected animals . The infective agent could be detected during the whole period of observation (6 months) . High sensitivity of the polymerase chain reaction made it possible to detect M.fermentans in much greater number of cases than with the use of serological techniques.

Eur J Clin Chem Clin Biochem, 1994 Aug, 32(8), 599 - 608
{Long-functioning beta-D-glucose and L-lactate biosensors for continuous flow-through measurements for "fouling"-resistant and selectivity-optimized serum- and hemoanalysis}; Schindler JG et al.; Bioelectrochemical membrane-electrodes for O2-sensitive enzymatic flow-through analysis of beta-D-glucose and L-lactate are described . The enzyme-membranes of the biosensors consist of glucose-oxidase or lactate-oxidase molecules cross-linked with glutardialdehyde between two dialysis membranes . The accuracy of the biosensors is demonstrated by electroanalysis of diluted control serum and compared with redox-mediator-free H2O2 detection and photometric methods . Continuous haemoanalysis of uncoagulated blood was carried out, using an intermediate carrier stream with additive systems . Tangential streaming to the miniaturized dialysis chamber with a circular channel minimizes blockage of the pores of the dialysis membrane by erythrocytes, leukocytes or protein . An oxygenator pump for the exchange of gases between the buffered solution of the intermediate carrier and the surrounding atmosphere guarantees a constant oxygen partial pressure within the carrier stream . The pulsations produced by the oxygenator pump are dampened by a miniature pressure balance chamber with an unsignificant dead space volume for protecting the enzyme membrane of the sensor . Glutardialdehyde inhibits growth of microorganisms and any resulting oxygen consumption, so that even in protein-containing measuring solutions enzyme electrodes can be used without interference from microbial contamination . The bioelectrochemical measuring system can therefore also be employed for the electroanalysis of fermentation solutions . For continuous flow-through measurements, it is necessary to change the glucose-oxidase membranes after 100-150 days, and the lactate-oxidase membranes after 3-6 weeks.

Eur J Surg, 1994 Aug, 160(8), 409 - 16
The lactulose hydrogen breath test as a measure of orocaecal transit time; Jorge JM et al.; OBJECTIVE: To establish normal values and assess the reproducibility of the lactulose hydrogen breath test in measuring orocaecal transit time in control subjects, and to report results in a group of patients with chronic constipation as a result of colonic inertia . DESIGN: Open study . SETTING: Academic clinic . SUBJECTS: 42 Control subjects (29 women and 13 men) in 25 of whom the test was repeated within 2-4 weeks, and 19 patients . INTERVENTIONS: Lactulose hydrogen breath test . MAIN OUTCOME MEASURES: Sustained increase in hydrogen production of 3 ppm or more . RESULTS: Coefficient of variation within subjects was 8% compared with 38% between subjects; 3 of the control subjects (7%) and 3 of the patients (16%) did not ferment lactulose, the the incidence was similar in men (1/13, 8%) and women (2/29, 7%) . Mean (SD) orocaecal transit time was significantly shorter among the 29 women (60 (27) minutes) than among the 11 men (89 (24) minutes) (p < 0.005) . There were no significant differences between men in the control group and those with constipation . CONCLUSIONS: The lactulose hydrogen breath test is valuable to assess orocaecal transit time . It is simple, non-invasive, and reproducible, and may be of value in differentiating between generalised hypomotility and colonic inertia.

Mol Biochem Parasitol, 1994 Aug, 66(2), 273 - 81
Differential expression of two succinate dehydrogenase subunit-B genes and a transition in energy metabolism during the development of the parasitic nematode Haemonchus contortus; Roos MH et al.; The carbohydrate metabolism of free-living and parasitic stages of the sheep nematode Haemonchus contortus was studied, and it was demonstrated that during development a switch occurred from Krebs-cycle activity towards a more fermentative metabolism . During this switch a transition might take place in complex II of the respiratory chain . In the free-living (L3) and early parasitic (XL3) stages, complex II catalyses the oxidation of succinate to fumarate via the Krebs cycle, whereas in adults complex II functions in the reverse reaction, the reduction of fumarate to succinate . L3 and XL3 were shown to already possess a large anaerobic capacity . They survived well in the absence of oxygen or in the presence of cyanide, which completely blocked respiration . Krebs-cycle activity, however, was only partially inhibited by cyanide; the XL3s in particular produced in the presence of cyanide large amounts of propanol, the production of which probably functions as an alternative electron sink . For further investigation of the observed metabolic switch, complex II of the respiratory chain, a key enzyme involved in this switch, was studied . The B subunit of complex II was cloned and sequenced . These clones all showed sequences similar to the B subunit of succinate dehydrogenase from other species, and included the amino-terminal signal sequence for importation into mitochondria . Two genes were identified, types 1 and 2, based on the DNA and amino acid sequences and on the lack of cross-reaction to each other when used as probes on Southern blots . On Northern blots, the two genes showed a different expression pattern during the development of the parasite.(ABSTRACT TRUNCATED AT 250 WORDS)

Trends Biotechnol, 1994 Aug, 12(8), 296 - 303
Purification of proteins by adsorption chromatography in expanded beds; Chase HA; Adsorption in stable expanded beds enables proteins to be recovered directly from particulate-containing feedstocks, such as fermentation broths and preparations of disrupted cells, without the need for prior removal of the suspended solids, which would normally result in the blockage of packed beds . The adoption of this technique will greatly reduce the complexity of downstream processing by eliminating certain filtration, centrifugation and concentration steps . Factors that are critical to the success of the procedure include the correct choice of adsorbent, together with careful design of the apparatus in which the separation is performed . The design, optimization and scale-up of appropriate operating protocols for expanded-bed procedures are very similar to those used for the operation of packed beds.

Gastroenterology, 1994 Aug, 107(2), 410 - 9
Butyrate is a potent inhibitor of urokinase secretion by normal colonic epithelium in vitro; Gibson PR et al.; BACKGROUND/AIMS: Because the neutral protease urokinase is important in control of cell adhesion and migration, the effects of the physiologically relevant fermentation product butyrate on urokinase secretion by colonic epithelium were examined . METHODS: Secreted and cell-associated levels of urokinase and plasminogen activator inhibitor 1 were measured in colonic crypt cells within 24 hours of isolation from macroscopically normal mucosa of normal or cancer-bearing colons . RESULTS: Butyrate caused a concentration-dependent inhibition of both secreted (56% +/- 4% inhibition after 24-hour exposure to 1 mmol/L butyrate; n = 20; mean +/- SEM; P < 0.001) and cell-associated urokinase content (35% +/- 6%; P = 0.003) . Acetate and propionate had minimal effects . Butyrate also stimulated plasminogen activator inhibitor 1 secretion by 25% +/- 7% (P = 0.013) . Net urokinase activities were suppressed in supernates and cell homogenates by butyrate . Levels of transcripts for urokinase and the inhibitor changed with butyrate exposure in parallel to the levels of secretion of the respective proteins . Cells from the cancer group showed significantly reduced inhibitor secretion and abnormal responses to butyrate (greater inhibition of urokinase secretion and no stimulation of inhibitor secretion), probably reflecting the diffuse disturbance of colonic epithelial biology associated with colorectal cancer . CONCLUSIONS: Butyrate has dual effects in markedly reducing colonic epithelial urokinase activity, and these may have important implications to understanding colonic epithelial physiology and the pathogenesis and treatment of colonic diseases.

Oral Microbiol Immunol, 1994 Aug, 9(4), 218 - 23
The role of the succinate pathway in sorbitol fermentation by oral Actinomyces viscosus and Actinomyces naeslundii; Takahashi N et al.; The sorbitol fermentation by Actinomyces viscosus and Actinomyces naeslundii was studied with washed sorbitol-grown cells . The fermentation was followed by titration of acids produced at pH 7.0 under anaerobic conditions . Metabolic end-products and intracellular levels of NAD, NADH and glycolytic intermediates during the fermentation were also analyzed . Cell extracts were examined for certain enzyme activities . Bicarbonate was required for acid production from sorbitol and from a mixture of glucose and sorbitol . Malate and fumarate could also support the acid production of A . viscosus . The main end-products were succinate and lactate but not ethanol . Cell extracts showed no activities of alcohol and aldehyde dehydrogenases, but they had activities of malate dehydrogenase and fumarate reductase . In the absence of bicarbonate, malate or fumarate, the intracellular NADH/NAD ratio increased and the levels of 3- and 2-phosphoglycerate and phosphoenolpyruvate decreased . The results indicate that oral sorbitol-fermenting actinomyces lack the ethanol pathway that can contribute to NADH oxidation . To maintain intracellular redox balance during anaerobic sorbitol fermentation, these bacteria can oxidize surplus NADH through a succinate pathway.

J Chromatogr A, 1994 Jul 22, 675(1-2), 101 - 12
Preparative isolation of recombinant human insulin-like growth factor 1 by reversed-phase high-performance liquid chromatography; Olson CV et al.; The isolation of recombinant human insulin-like growth factor 1 (rhIGF-1) is complicated by the presence of several rhIGF-1 variants which co-purify using conventional chromatographic media . These species consist primarily of a methionine-sulfoxide variant of the properly folded molecule and a misfolded form and its respective methionine-sulfoxide variant . An analytical reversed-phase high-performance liquid chromatography procedure using a 5-micron C18 column, an acetonitrile-trifluoroacetic acid (TFA) isocratic elution, and elevated temperature gives baseline resolution of the four species . Using this analytical method as a development tool, a process-scale chromatography step was established . The 5-micron analytical packing material was replaced with a larger-size particle to reduce back-pressure and cost . Since the TFA counter-ion binds tightly to proteins and is difficult to subsequently dissociate, a combination of acetic acid and NaCl was substituted . Isocratic separations are not good process options due to problems with reproducibility and control . A shallow gradient elution using premixed mobile phase buffers at the same linear velocity was found to give an equivalent separation at low load levels and minimized solvent degassing . However, at higher loading there was a loss of resolution . A matrix of various buffers was evaluated for their effects on separation . Elevated pH resulted in a significant shift in both the elution order and relative retention times of the principal rh-IGF-1 variants, resulting in a substantial increase in effective capacity . An increase in the ionic strength further improved resolution . Several different media were evaluated with regard to particle size, shape and pore diameter using the improved mobile phase . The new conditions were scaled up 1305-fold and resulted in superimposable chromatograms, 96% recovery and > 99% purity . Thus, by optimizing the pH, ionic strength and temperature, a high-capacity preparative separation of rhIGF-1 from its related fermentation variants was obtained.

J Biol Chem, 1994 Jul 8, 269(27), 18192 - 200
Cloning and disruption of CKB2, the gene encoding the 32-kDa regulatory beta'-subunit of Saccharomyces cerevisiae casein kinase II; Reed JC et al.; Casein kinase II of Saccharomyces cerevisiae is composed of two distinct catalytic subunits, alpha and alpha', and two distinct regulatory subunits, beta and beta' (Padmanabha, R . and Glover, C . V . C . (1987) J . Biol . Chem . 262, 1829-1835; Bidwai, A . P., Reed, J . C., and Glover, C . V . C . (1994) Arch . Biochem . Biophys . 309, 348-355) . We report here the cloning, sequencing, and disruption of the CKB2 gene encoding the beta'-subunit . The deduced amino acid sequence of Ckb2 displays only 40-45% identity to other beta-subunit sequences reported to date, allowing a better definition of conserved features of this protein . Most notable is the conservation of a cysteine-containing sequence, CPX3C-X22-CPXC, which may constitute a novel metal-binding motif . The degree of sequence divergence of Ckb2 is comparable to that of the Drosophila Stellate protein, a testis-specific protein of unknown function, suggesting that the latter may function as a second beta-subunit in Drosophila . CKB2 is located on the right arm of chromosome XV between the HIR2 and WHI2 loci and has not been previously identified genetically . Haploid and homozygous diploid cells harboring a ckb2 null allele are viable, demonstrating that the beta'-subunit does not have an essential function distinct from that of beta . Strains lacking a functional CKB2 gene appear to grow normally on both fermentable and non-fermentable carbon sources, mate and sporulate normally, and display normal resistance to nitrogen starvation and heat shock . However, haploid strains harboring disruptions of both the beta' gene and either of the catalytic subunit genes exhibit a synthetic phenotype consisting of slow growth and flocculation in rich glucose medium . The occurrence of this synthetic phenotype implies that the beta'-subunit interacts physically and/or functionally with both the alpha- and alpha'-subunits in vivo.

Biochim Biophys Acta, 1994 Jul 6, 1200(2), 155 - 60
Differential changes in the activity of cytosolic and vacuolar trehalases along the growth cycle of Saccharomyces cerevisiae; San Miguel PF et al.; Saccharomyces cerevisiae cells contain two intracellular and soluble trehalases with distinct subcellular location (cytosol and vacuoles, respectively) . Both enzymes showed an opposite pattern of activity along the growth cycle . Activity of the cytosolic trehalase was high in cells growing exponentially on fermentable sugars (glucose, mannose or galactose) and sharply decayed as the cultures enter stationary phase coinciding with the beginning of trehalose biosynthesis . By contrast, vacuolar trehalase was only detectable in glucose-grown resting cells or in cultures growing on respiratory substrates (glycerol or ethanol) . This enzyme was partially derepressed in the mutant hex2, which is deficient in glucose repression . Addition of fresh YPD medium to stationary-phase cultures induced the sudden reactivation of cytosolic trehalase with the concomitant slower inactivation of vacuolar trehalase . However, addition of glucose or various nitrogen sources alone had only a minor effect on both activities . The presence of cycloheximide had no effect on cytosolic trehalase, whereas completely blocked the appearance of vacuolar trehalase suggesting the requirement of protein synthesis 'de novo'.

ASAIO J, 1994 Jul-Sep, 40(3), M743 - 6
Feasibility studies for a photosynthetic artificial lung . Optimization of parameters affecting photosynthesis; Basu S et al.; As an alternative to conventional extracorporeal membrane oxygenation (ECMO) hardware, preliminary studies were conducted toward the development of a life support system based on biologic processes for the direct generation of O2 and removal of CO2 by the action of a photosynthetic organism . A high temperature strain of Chlorella pyrenoidosa, which functions optimally at 37 degrees C and pH 7.4, was cultured in a 3 I fermenter with artificial lighting provided with Hg-metal halide lights . The pH, total CO2 and partial pressure of oxygen (PO2) of the system were monitored at regular intervals using flow-through microelectrodes . The degree of importance of light intensity, substrate concentration, and cell density in the photosynthetic ability of Chlorella in batch culture were assessed over a 2 hour period . At high light intensities, the O2 production, CO2 removal, and pH changes were significantly greater than those at low irradiance levels . Over the range of HCO3- concentrations used in these experiments, the initial HCO3- levels did not appear to have a significant effect on the rates of O2 production/CO2 removal . The total amount of O2 produced/CO2 removed and pH changes were found to be greater with higher cell densities . Under more optimal culture conditions, it may be feasible to eventually interface this photobioreactor with blood across a semipermeable membrane and catalytically convert blood CO2 to O2 directly, needing only an adequate light source.

Microbiology, 1994 Jul, 140 ( Pt 7), 1723 - 9
Is the Kluyver effect in yeasts caused by product inhibition?
Weusthuis RA, Luttik MA, Scheffers WA, van Dijken JP, Pronk JT.
Candida utilis CBS 621 exhibits the Kluyver effect for maltose, i.e . this yeast can respire maltose and is able to ferment glucose, but is unable to ferment maltose . When glucose was pulsed to a maltose-grown, oxygen-limited chemostat culture of C . utilis, ethanol formation from glucose started almost instantaneously, indicating that the enzymes needed for alcoholic fermentation are expressed in maltose-grown cells . However, the addition of glucose inhibited maltose metabolism . To eliminate a possible catabolite inhibition and/or repression of enzyme activities involved in maltose metabolism, the effect of simultaneously feeding glucose and maltose to an oxygen-limited, maltose-grown chemostat culture was studied . In this case, the glucose concentration in the culture remained below 0.1 mM, which makes glucose catabolite repression unlikely . Nevertheless, maltose metabolism appeared to cease when the culture was switched to the mixed feed . Based on the outcome of the mixed-substrate studies, it was postulated that the Kluyver effect may be caused by feedback inhibition of maltose utilization by ethanol, the product of fermentative maltose metabolism . If ethanol suppresses the utilization of non-fermentable disaccharides, this would provide a phenomenological explanation for the occurrence of the Kluyver effect: accumulation would then not occur and the rate of maltose metabolism would be tuned to the culture's respiratory capacity . This hypothesis was tested by studying growth of C . utilis CBS 621 and Debaryomyces castellii CBS 2923 in aerobic batch cultures on mixtures of sugars and ethanol.(ABSTRACT TRUNCATED AT 250 WORDS)

Appl Environ Microbiol, 1994 Jul, 60(7), 2657 - 60
Cloning of the macrolide antibiotic biosynthesis gene acyA, which encodes 3-O-acyltransferase, from Streptomyces thermotolerans and its use for direct fermentative production of a hybrid macrolide antibiotic; Arisawa A et al.; A gene encoding the macrolide modification enzyme 3-O-acyltransferase (acyA) was cloned by chromosome walking onto the carbomycin biosynthetic region in Streptomyces thermotolerans TH475, with the 3' region of the gene encoding the macrolide modification enzyme 4"-O-acyltransferase (acyB1) as a probe . A shortened fragment (1.8 kb) containing acyA was subcloned with pIJ350 . A high-level tylosin producer, Streptomyces fradiae MBBF, transformed with the plasmid could produce a hybrid macrolide, 3-O-acetyltylosin, most efficiently.

Appl Environ Microbiol, 1994 Jul, 60(7), 2533 - 7
Ability of Acidaminococcus fermentans to oxidize trans-aconitate and decrease the accumulation of tricarballylate, a toxic end product of ruminal fermentation; Cook GM et al.; Mixed ruminal bacteria convert trans-aconitate to tricarballylate, a tricarboxylic acid which chelates blood divalent cations and decreases their availability (J . B . Russell and P . J . Van Soest, Appl . Environ . Microbiol . 47:155-159, 1984) . Decreases in blood magnesium in turn cause a potentially fatal disease known as grass tetany . trans-Aconitate was stoichiometrically reduced to tricarballylate by Selenomonas ruminantium, a common ruminal bacterium in grass-fed ruminants (J . B . Russell, Appl . Environ . Microbiol . 49:120-126, 1985) . When mixed ruminal bacteria were enriched with trans-aconitate, a trans-aconitate-oxidizing bacterium was also isolated (G . M . Cook, F . A . Rainey, G . Chen, E . Stackebrandt, and J . B . Russell, Int . J . Syst . Bacteriol . 44:576-578, 1994) . The trans-aconitate-oxidizing bacterium was identified as Acidaminococcus fermentans, and it converted trans-aconitate to acetate, a nontoxic end product of ruminal fermentation . When S . ruminantium and A . fermentans were cocultured with trans-aconitate and glucose, tricarballylate never accumulated and all the trans-aconitate was converted to acetate . Continuous-culture studies (dilution rate, 0.1 h-1) likewise indicated that A . fermentans could outcompete S . ruminantium for trans-aconitate . When mixed ruminal bacteria were incubated in vitro with 10 mM trans-aconitate for 24 h, 45% of the trans-aconitate was converted to tricarballylate . Tricarballylate production decreased 50% if even small amounts of A . fermentans were added to the incubation mixes (0.01 mg of protein per mg of mixed bacterial protein) . When A . fermentans (2 g of bacterial protein) was added directly to the rumen, the subsequent conversion of trans-aconitate to tricarballylate decreased 50%, but this effect did not persist for more than 18 h.(ABSTRACT TRUNCATED AT 250 WORDS)

Appl Environ Microbiol, 1994 Jul, 60(7), 2248 - 51
Variability among atoxigenic Aspergillus flavus strains in ability to prevent aflatoxin contamination and production of aflatoxin biosynthetic pathway enzymes; Cotty PJ et al.; Five strains of Aspergillus flavus lacking the ability to produce aflatoxins were examined in greenhouse tests for the ability to prevent a toxigenic strain from contaminating developing cottonseed with aflatoxins . All atoxigenic strains reduced contamination when inoculated into developing bolls 24 h prior to the toxigenic strain . However, only one strain, AF36, was highly effective when inoculated simultaneously with the toxigenic strain . All five strains were able to inhibit aflatoxin production by the toxigenic strain in liquid fermentation . Thus, in vitro activity did not predict the ability of an atoxigenic strain to prevent contamination of developing bolls . Therefore, strain selection for competitive exclusion to prevent aflatoxin contamination should include evaluation of efficacy in developing crops prior to field release . Atoxigenic strains were also characterized by the ability to convert several aflatoxin precursors into aflatoxin B1 . Four atoxigenic strains failed to convert any of the aflatoxin biosynthetic precursors to aflatoxins . However, the strain (AF36) most effective in preventing aflatoxin contamination in developing bolls converted all tested precursors into aflatoxin B1, indicating that this strain made enzymes in the aflatoxin biosynthetic pathway.

J Antibiot (Tokyo), 1994 Jul, 47(7), 774 - 81
Cytosaminomycins, new anticoccidial agents produced by Streptomyces sp . KO-8119 . I . Taxonomy, production, isolation and physico-chemical and biological properties; Haneda K et al.; Streptomyces amakusaensis KO-8119, a soil isolate, was found to produce a series of new anticoccidial compounds . Four active compounds, designated as cytosaminomycins A, B, C and D, were isolated from the fermentation broth of the producing strain by solvent extraction, silica gel column chromatography and preparative HPLC . Cytosaminomycins inhibited the growth of Eimeria tenella in an in vitro assay system using primary chicken embryonic cells as a host . No schizont in the cells was observed at concentrations ranging from 0.3 to 0.6 microgram/ml for cytosaminomycins A, B and C, and at 2.5 micrograms/ml for cytosaminomycin D.

J Antibiot (Tokyo), 1994 Jul, 47(7), 755 - 64
Pneumocandin D0, a new antifungal agent and potent inhibitor of Pneumocystis carinii; Morris SA et al.; Pneumocandin D0 (9), a new member of the echinocandin class of antifungal agents, has been isolated as a minor constituent from fermentation broths of the filamentous fungi Zalerion arboricola (ATCC 20957) . The structure of 9 has been determined mainly on the basis of spectroscopic analysis and by comparison with published data for similar compounds . To date, pneumocandin D0 has been found to be the most potent inhibitor of Pneumocystis carinii development in vivo within the natural-occurring echinocandin family of antifungal agents.

Biol Mass Spectrom, 1994 Jul, 23(7), 430 - 3
Measurement of whole body acetate turnover in healthy subjects with stable isotopes; Simoneau C et al.; Colonic fermentation of dietary fibres produces short-chain fatty acids (e.g . acetate, propionate) . Measurements of whole body acetate turnover was used in order to estimate the production of colonic short-chain fatty acids in human subjects . However, higher flux rates for acetate have been reported in human studies with stable isotopes as compared to radioactive tracers . The reasons for this discrepancy are unclear . In this study, the stable isotope (1-13C)acetate was used and a method was developed to measure its enrichment in plasma . Variations between and within assays were less than 5% . The standard curve was linear from 0.5% to 10% enrichment . When this tracer was infused for 160 min in six healthy volunteers, acetate turnover was found to be 7.5 +/- 1 mumol kg-1 min-1, which is similar to data reported with radioactive tracers . We assumed that the higher flux rate previously observed with stable isotope tracers was related to differences in the physiological status of the subjects involved in these studies.

Int J Syst Bacteriol, 1994 Jul, 44(3), 576 - 8
Emendation of the description of Acidaminococcus fermentans, a trans-aconitate- and citrate-oxidizing bacterium; Cook GM et al.; Ruminal fluid which was enriched with trans-aconitate yielded a gram-negative diplococcus (strain AO) which was identified by 16S ribosomal DNA sequence analysis as Acidaminococcus fermentans . In contrast to the original description, the A . fermentans type strain and strain AO were found to utilize citrate as an energy source and to produce hydrogen and hydrogen sulfide . The descriptions of the genus and species are emended accordingly.

FEMS Microbiol Lett, 1994 Jul 1, 120(1-2), 87 - 91
Induction of respiration-deficient mutants in Saccharomyces cerevisiae by chelerythrine; Krivjansky V et al.; Chelerythrine and sanguinarine, two structurally related benzo/c/phenanthridine alkaloids, prevented growth of yeast cells in medium containing either glucose or non-fermentable carbon sources . At concentrations permitting growth of the yeast Saccharomyces cerevisiae, chelerythrine, but not sanquinarine, induced cytoplasmic respiration-deficient mutants . The petite clones that were analysed exhibited suppressiveness and contained different fragments of the wild-type mitochondrial genome.

J Biol Chem, 1994 Jul 1, 269(26), 17537 - 41
Evidence for the operation of a novel Embden-Meyerhof pathway that involves ADP-dependent kinases during sugar fermentation by Pyrococcus furiosus; Kengen SW et al.; The main pathway for the fermentation of maltose or cellobiose by the hyperthermophile Pyrococcus furiosus was investigated by in vivo NMR and by enzyme measurements . Addition of {1-13C}glucose to cell suspensions resulted in the formation of C2-labeled acetate and C3-labeled alanine . No label was recovered in CO2 or HCO3- . In the presence of {3-13C}glucose, the label ended up in the C1 atom of alanine and in HCO3- and CO2 . These labeling patterns indicate that glucose is converted along an Embden-Meyerhof pathway, and they disagree with the previously proposed nonphosphorylated Entner-Doudoroff pathway (pyroglycolysis) . The NMR data were supported by enzyme measurements . Hexokinase (8.7 units/mg), phosphoglucose isomerase (6.8 units/mg), phosphofructokinase (0.81 unit/mg), and aldolase (0.26 unit/mg) were present in cell-free extracts (specific activities at 90 degrees C) . Remarkably, the two kinases required ADP as the phosphoryl group donor instead of ATP . No activity was found with pyrophosphate . These are the first descriptions of ADP-dependent (AMP-forming) kinases to date . Since P . furiosus is a phylogenetically ancient organism, these enzymes may represent an ancestral kind of metabolism.

Zh Mikrobiol Epidemiol Immunobiol, 1994 Jul-Aug, (4), 81 - 4
{The preventive properties and therapeutic efficacy of an antitetanus immunoglobulin for experimental intravenous administration}; Sapozhnikova VS et al.; The new preparation of antitetanus immunoglobulin for intravenous injection has been developed at the Kirov Research Institute of Hematology and Blood Transfusion . The technology for obtaining this preparation is based on the method of acidic fermentative hydrolysis . The preparation has high specific potency: one dose contains at least 1,500 I.U . of tetanus antitoxin . As demonstrated in the experimental study of the preparation on mice, its intravenous injection 0.5 hours after challenge completely neutralizes the action of tetanus toxin, its use 24 hours after challenge protects all animals from death, while eliminating the clinical signs of the disease in 50% of them . The intramuscular injection of the preparation has proved to be considerably less effective.

Zh Mikrobiol Epidemiol Immunobiol, 1994 Jul-Aug, (4), 13 - 6
{The physicochemical characteristics of a chick embryo hydrolysate-based nutrient broth}; Migunov AI et al.; The composition of dried nutrient broth, prepared on the basis of the fermentative hydrolysate of waste chick embryos, has been studied with the use of physicochemical analytical methods . The parameters of total and amino nitrogen, the content of amino acids, peptides, lipids, carbohydrates and microelements have been determined . The qualitative analysis of the peptide composition of the broth has been made . The heterogeneity of peptides with respect to their molecular weights (200--15,000 D and over) has been noted . As regards its physico-chemical composition, the broth is a valid medium, suitable for the cultivation of a wide spectrum of microorganisms.

Mol Microbiol, 1994 Jul, 13(2), 172 - 82
The energetics of bacterial growth: a reassessment; Neijssel OM et al.; The growth yield of microbial cultures can be used to estimate the efficiency of energy generation during a fermentation or respiration . In the past, the assessment of this efficiency in organisms carrying out a respiration has been the subject of many heated debates . This has partly been caused by the complexity of microbial respiratory chains . Strains of Escherichia coli specifically modified in their respiratory chain have been used recently to re-evaluate the energetic efficiency of the bacterial respiration using chemostat cultures . The different strains indeed show different growth efficiencies . The physiological significance of energetically less-efficient branches of the respiratory chain is discussed.

Curr Genet, 1994 Jul, 26(1), 8 - 14
The yeast nuclear gene MRP-L13 codes for a protein of the large subunit of the mitochondrial ribosome; Grohmann L et al.; The nuclear gene MRP-L13 of Saccharomyces cerevisiae, which codes for the mitochondrial ribosomal protein YmL13, has been cloned and characterized . It is a single-copy gene residing on chromosome XI . Its nucleotide sequence was found to be identical to that of the previously reported ORF YK105 . A comparison of the predicted protein sequence of the MRP-L13 gene product and the actual N-terminal amino-acid sequence of the isolated YmL13 protein indicated that the mature protein is preceded by a mitochondrial signal peptide of 86 amino-acid residues, which is the longest among all known mitochondrial ribosomal proteins of S . cerevisiae . No sequence similarity was found to any other ribosomal protein in the current databases . The transcription of MRP-L13 was found to be repressed in the presence of glucose . Its protein product is not strictly essential for mitochondrial functions, but disruption of the gene by insertion of LEU2 noticeably affected cellular growth on non-fermentable carbon sources.

Zentralbl Pathol, 1994 Jul, 140(2), 143 - 8
Autolysosomes in Alzheimer's disease and their possible role in its pathogenesis . An ultrastructural study; Soustek Z; In 10 cases of senile dementia of Alzheimer's type (AD) a systematic post-mortem ultrastructural analysis was performed . Attention was paid mainly to the presence of autolysosomes in the neuropil of the brain cortex . Autolysosomes appeared as osmiophilic dense bodies (DB) which originated in synaptic terminals and peripheral nerve-cell processes . DBs contained sequestrated cellular material wrapped by pinched off, invaginated cell membrane . DB were very frequent also in fields where no senile plaques (SP) and/or nerve-cell processes with paired helical filaments (PHF) were present . Abnormal fermentative degradation of DBs and their possible negative influence on the plasmatic flow in nerve-cell processes is discussed.

Pharm Res, 1994 Jul, 11(7), 990 - 4
Microbial and mammalian metabolism studies of the semisynthetic antimalarial, anhydrodihydroartemisinin; Khalifa SI et al.; Microbial metabolism studies of the semisynthetic antimalarial anhydrodihydroartemisinin (1), have shown that it is metabolized by a number of microorganisms . Large scale fermentation with Streptomyces lavendulae L-105 and Rhizopogon species (ATCC 36060) have resulted in the isolation of four microbial metabolites . These metabolites have been identified as a 14-carbon rearranged product (2), 9 beta-hydroxyanhydrodihydroartemisinin (3), 11-epi-deoxydihydroartemisinin (4), and 3 alpha-hydroxydeoxyanhydrodihydroartemisinin (5) . Microbial metabolites were completely characterized by spectral methods, including 1H-NMR and 13C-NMR spectroscopy . The structure and stereochemistry of metabolite 2 were unequivocally established by X-ray crystallographic analysis . Thermospray mass spectroscopy/high-performance liquid chromatographic analyses of plasma from rats used in mammalian metabolism studies of 1 have shown microbial metabolite 3 to be the major mammalian metabolite . In vitro antimalarial testing has shown metabolite 3 to possess antimalarial activity.

J Dairy Sci, 1994 Jul, 77(7), 2031 - 43
Protein systems for feeding ruminant livestock: a European assessment; Beever DE et al.; The metabolizable protein system for ruminants, published recently in the United Kingdom (2), was based upon earlier proposals (3, 4) . The system includes a number of changes designed to represent the extent of protein degradation in the rumen and the synthesis of microbial protein as variable functions . The system also provides a more rational description of the energy available for microbial growth (fermentable metabolizable energy) by discounting the energy content of dietary lipids and fermentation end products (silages), which are considered to make a relatively insignificant contribution or none to microbial metabolism . The assessment of availability of undegraded dietary protein in the small intestine is revised also, and variable efficiencies of utilization of absorbed AA in relation to the nature of the synthetic process (e.g., meat and milk) are proposed . This paper considers these changes and assesses the adequacy of current laboratory techniques for determining the protein value of feedstuffs for ruminants . A number of conceptual and technical problems are identified, and ways of overcoming them are discussed . We conclude that such systems must be used in practice with guarded enthusiasm and suggest that mechanistic models, which provide a more appropriate representation of the biological processes, be encouraged as the basis of the next generation of feeding systems.

J Clin Microbiol, 1994 Jul, 32(7), 1654 - 7
Biotypes of Arcanobacterium haemolyticum; Carlson P et al.; Colony morphology, beta hemolysis on horse blood agar, beta-glucuronidase activity, and ability to ferment sucrose and/or trehalose defined two biotypes of Arcanobacterium haemolyticum . One, the smooth type, grew as smooth, beta-hemolytic colonies and was beta-glucuronidase negative but often fermented sucrose and/or trehalose, while the other, the rough type, grew as rough colonies and was nonhemolytic, beta-glucuronidase positive, and negative for sucrose and trehalose fermentation . About 75% of the A . haemolyticum strains studied (n = 138) were of the smooth type . The smooth type predominated in wound infections, while the rough type was isolated almost exclusively from respiratory tract specimens; thus, 84% of the smooth-type strains were derived from wounds and 91% of the rough-type strains were isolated from respiratory tracts.

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