Fermentations

Ukr Biokhim Zh, 1994 Jul-Aug, 66(4), 43 - 51
{Formate metabolism by lactate-producing and lactate-utilizing rumen bacteria}; Kalachniuk GI et al.; Physiological concentrations {< 11 mM} of formate do not violate the metabolism of S . bovis and M . elsdenii . A significant inhibition is caused by concentrations of 22 and 44 mM . In this case the process of ammonia formation in S . bovis is inhibited more pronouncedly . Peculiar effects of formate (11 mM) on LDH, FDH, aconitase, isocitrate dehydrogenase, fumarase, L-MDH and malic-enzyme have been stated . The changes show that it enhances assimilation of sugars fermented to lactate in S . bovis, in contrast to M . elsdenii, where it activates the utilization of lactic acid . During the log-phase S . bovis utilized only 11.5% of {14C} H2O2, whereas M . elsdenii uses 33.4% of it . The major amount of the label is transferred from intracellular inclusions to nucleic acids (in S . bovis--74.7%, in M . elsdenii--87%) and then incorporated into low molecular substances (23.5 and 11.9%, respectively), the rest being incorporated into proteins and lipids.

Adv Dent Res, 1994 Jul, 8(2), 239 - 45
Saliva stimulation and caries prevention; Edgar WM et al.; The protective role of saliva is demonstrated by the rampant caries seen in human subjects with marked salivary hypofunction, and in desalivated animals . In normal cases, however, the relationship between saliva flow and coronal or root caries experience is doubtful, and to examine the concept that stimulation of saliva might have protective effects against caries, one must look beyond a simple correlation between caries and flow rate . Protective properties of saliva which increase on stimulation include salivary clearance, buffering power, and degree of saturation with respect to tooth mineral . These benefits are maximized when saliva is stimulated after the consumption of fermentable carbohydrates, by reducing the fall in plaque pH leading to demineralization and by increasing the potential for remineralization . Plaque acid production is neutralized, and experimental lesions in enamel are remineralized, when gum is chewed to stimulate saliva after a carbohydrate intake . The pH-raising effects are more easily explained by the buffering action of the stimulated saliva than by clearance of carbohydrates . The remineralization action depends upon the presence of fluoride . These findings suggest that the protective actions of saliva can be mobilized by appropriate salivary stimulation, and that in addition to established procedures such as tooth cleaning and fluoride regimens, eating patterns which lead to saliva stimulation to increase the potential for saliva protection might be included in recommendations for caries prevention . Confirmation of this concept in clinical tests is required.

Adv Dent Res, 1994 Jul, 8(2), 221 - 4
Diet patterns and caries; Geddes DA; Few dietary studies have been designed to investigate the effects of intake patterns of food items upon the environment of the teeth . This brief review considers evidence about the effects of choice, combination, and sequence of ingested food and drink upon the pH of human dental plaque in vivo . A series of three studies, which were designed to investigate some of the intra-oral biological events associated with cariogenicity during various eating patterns, are discussed . The principal findings show that if a "meal" includes an item which contains carbohydrate such as sucrose, glucose, or fructose which is rapidly fermented by the acidogenic microorganisms in dental plaque, there will be rapid acid production and the plaque pH will fall . However, other items eaten immediately before, during, or after the consumption of the sugary item can influence the plaque pH . If the non-sugary item stimulates saliva, it will have a pH-raising effect . The remineralizing potential may be enhanced if, for instance, calcium or fluoride is released from the food . However, if one sugary item is followed by another, the demineralizing potential may be enhanced . The results of these experiments are discussed in the context of our current understanding of the dynamics of the carious process . Recent preliminary experiments suggest that other factors, such as the individual subject's speed of consumption, may also affect the cariogenic potential of the oral environment.

Biotechnol Prog, 1994 Jul-Aug, 10(4), 428 - 32
A novel ultrasonic resonance field device for the retention of animal cells; Doblhoff-Dier O et al.; This article describes two types of flow-through cell retention devices based on the concept of layered piezoelectric resonators . A single-chamber device is compared to a novel optimized steam-sterilizable prototype ultrasonic cell separator with improved acoustic design and an integrated cooling circuit, eliminating the problem of local temperature increase caused by the high amplitudes necessary to achieve the separation of animal cells with low acoustic contrast . This setup yields highly reproducible results and is ideal for studying the long-term effects of ultrasonic sound fields and separation efficiency . The novel two-chamber system has the potential for scaleability due to the reduction in thermal and acoustic flow, increased field stability, and separation efficiency . Finally, the effect of power input on separation and cell viability is reported . Such flow-through cell retention systems could be used as systems to retain biomass within the fermentor or as a substitute for centrifugation, with the major advantage of eliminating high-speed rotational motion.

J Ind Microbiol, 1994 Jul, 13(4), 225 - 32
Glucose and acetate influences on the behavior of the recombinant strain Escherichia coli HB 101 (GAPDH); Gschaedler A et al.; This study highlights data about the production of a recombinant protein (glyceraldehyde-3-phosphate dehydrogenase) by E . coli HB 101 (GAPDH) during batch and fed-batch fermentations in a complex medium . From a small number of experiments, this strain has been characterized in terms of protein production performance and glucose and acetate influences on growth and recombinant protein production . The present results show that this strain is suitable for recombinant protein production, in fed-batch culture 55 g L-1 of biomass and 6 g L-1 of GAPDH are obtained . However this strain, and especially GAPDH overproduction is sensitive to glucose availability . During fermentations, maximum yields of GAPDH production have been obtained in batch experiments for glucose concentration of 10 g L-1, and in fed-batch experiments for glucose availability of 10 g h-1 (initial volume 1.5 L) . The growth of the strain and GAPDH overproduction are also inhibited by acetate . Moreover acetate has been noted as an activator of its own formation.

Rev Latinoam Microbiol, 1994 Jul-Sep, 36(3), 177 - 81
{Moraxella bovis biomass production in a bench-top fermentor}; Gonzalez RD et al.; A Moraxella bovis strain was isolated from a kerato-conjunctivities lesion of a calf in Villa Valeria (Cordoba); it was used to establish improved cultural conditions, such as nature and concentration of carbon and nitrogen sources, and pH control in shaken flasks . The selected conditions were assayed for biomass production in a bench-top fermentor . The strain is used by the pharmaceutical industry to produce vaccines and adjuvants . In the initial condition (48 h culture on blood agar) 0.019 g biomass/l.h-1 was obtained . With the use of liquid defined medium with pH control, productivity was increased to 0.153g/l.h-1, with optimum harvest time of 32 h.

Mycopathologia, 1994 Jul, 127(1), 19 - 27
Secondary metabolites of Penicillium bilaii strain PB-50; Savard ME et al.; A phosphate-solubilizing strain of Penicillium bilaii was tested for the production of gliotoxin and other toxic compounds . The strain was fermented under five different conditions to allow the expression of various metabolites, including gliotoxin . These included Czapek-yeast extract medium under both shaken and still conditions as well as Czapek-yeast extract/malt extract/peptone medium and sucrose/glycerol medium in shake flasks . In addition, culture filtrate from an industrial fermentation of the fungus was examined . No gliotoxin was produced in any of the media . No other expected P . bilaii metabolites were found . Three compounds were identified in all samples: dibutyl phthalate, 1-(4-hydroxy-phenyl)ethanone and 4-hydroxy-3,6-dimethyl-2H-pyran-2-one . The production of other metabolites was dependent on the culture conditions . Two hyalodendrin derivatives were found in some fermentations and two related compounds were tentatively identified . None of the compounds found have been reported as toxic . The identity of the culture was confirmed by comparison with the ex-type culture of P . bilaii.

J Biol Chem, 1994 Jun 17, 269(24), 16726 - 32
Indolepyruvate ferredoxin oxidoreductase from the hyperthermophilic archaeon Pyrococcus furiosus . A new enzyme involved in peptide fermentation; Mai X et al.; Pyrococcus furiosus is a strictly anaerobic archaeon that grows optimally at 100 degrees C by a fermentative-type metabolism in which complex peptide mixtures such as yeast extract and Tryptone, and also certain sugars, are oxidized to organic acids, H2 and CO2 . Enzymes involved in the utilization of peptides such as proteases, aromatic amino transferases, and glutamate dehydrogenase have been previously purified from this organism . It is shown here that P . furiosus also contains significant cytoplasmic concentrations of a new enzyme termed indolepyruvate ferredoxin oxidoreductase (IOR) . This catalyzes the oxidative decarboxylation of aryl pyruvates, which are generated by the transamination of aromatic amino acids, to the corresponding aryl acetyl-CoA . IOR is a tetramer (alpha 2 beta 2) of two identical subunits (66,000 and 23,000 Da) with a molecular weight of 180,000 . The enzyme contains one molecule of thiamine pyrophosphate and four {4Fe-4S}2+,1+ and one {3Fe-4S}0,1+ cluster, as determined by iron analyses and EPR spectroscopy . Significant amounts of other metals such as copper and zinc were not detected . IOR was virtually inactive at 25 degrees C and exhibited optimal activity above 90 degrees C (at pH 8.0) and at pH 8.5-10.5 (at 80 degrees C) . The enzyme was sensitive to inactivation by O2, losing 50% of its activity after exposure to air for 20 min at 23 degrees C, and was quite thermostable, with a half-life of activity at 80 degrees C (under anaerobic conditions) of about 80 min . The Km values (in microM) for indolepyruvate, p-hydroxyphenylpyruvate, phenylpyruvate, CoASH, and P . furiosus ferredoxin, the physiological electron carrier, were 250, 110, 90, 17, and 48, respectively . IOR was inhibited by KCN (apparent Ki = 7.5 mM), but not by CO (1 atm) . An enzyme analogous to IOR has not been reported previously . Curiously, it has few properties in common with the pyruvate ferredoxin oxidoreductase of P . furiosus, even though the two enzymes catalyze virtually identical reactions . In fact, of known ketoacid oxidoreductases, the catalytic mechanism of IOR appears to be most similar to that of the pyruvate ferredoxin oxidoreductase from the hyperthermophilic bacterium Thermotoga maritima.

Cancer Res, 1994 Jun 15, 54(12), 3186 - 90
Fermented dairy products, calcium, and colorectal cancer in The Netherlands Cohort Study; Kampman E et al.; Experimental studies suggest that an increased consumption of fermented dairy products and calcium might decrease the risk of colorectal cancer . The associations between fermented dairy products, dietary calcium, and colorectal cancer risk were investigated in a population with a wide variation in intake of dairy products . The Netherlands Cohort Study of diet and cancer started in 1986 when 120,852 Dutch men and women, ages 55-69, filled out a questionnaire concerning dietary patterns and lifestyle . The present analysis is based on 3.3 years of follow-up and includes 215 incident cases of colon cancer and 111 incident cases of rectal cancer, excluding cases diagnosed in the first year of follow-up . After adjustment for potential confounding variables, colorectal cancer risk was weakly inversely associated with the consumption of fermented milk {relative rate (RR) in the highest category of intake compared to nonusers, 0.89; 95% confidence interval (CI), 0.60, 1.33}, unfermented milk (RR, 0.86; 95% CI, 0.57, 1.29), and cheese (RR, 0.88; 95% CI, 0.59, 1.33) . However, category-specific relative rates and tests for trends were not statistically significant . For fermented milk, the inverse association was limited to colon cancer (RR, 0.70; 95% CI, 0.43, 1.15; trend, P = 0.33) . In crude and multivariate models, total dietary calcium intake (highest versus lowest quintile, RR, 0.92; 95% CI, 0.64, 1.34) and calcium from fermented dairy products (RR, 1.14; 95% CI, 0.77, 1.68) were not significantly associated with colorectal cancer risk . Calcium from unfermented dairy products was inversely associated with rectal cancer risk (RR, 0.55; 95% CI, 0.30, 1.04; trend, P = 0.03) . After 3.3 years of follow-up, these data are not consistent with a substantially decreased risk of colorectal cancer with increased intake of fermented dairy products and dietary calcium.

J Biol Chem, 1994 Jun 3, 269(22), 15469 - 72
Structure and regulation of SDH3, the yeast gene encoding the cytochrome b560 subunit of respiratory complex II; Daignan-Fornier B et al.; Using an expression library, we have isolated yeast genes activated in the presence of the yeast CCAAT box-binding protein HAP2 . One of these genes, SDH3, encodes the cytochrome b560 subunit of respiratory complex II . The SDH3 protein contains three potential transmembrane domains and is more than 30% identical to bovine cytochrome b560 and to a mitochondrially encoded protein from Marchantia polymorpha . Disruption of SDH3 shows that this gene is required for growth on non-fermentable carbon sources . Expression of SDH1, SDH3, and SDH4 is activated in the presence of the HAP2 transcriptional activator.

J Chromatogr B Biomed Appl, 1994 Jun 3, 656(1), 81 - 5
Rapid assay of dinitrophenyl derivative of taurine by high-performance liquid chromatography; Polanuer B et al.; A rapid and simple method for the determination of taurine (2-aminoethanesulphonic acid) in complex samples is described . It is based on the HPLC separation of the dinitrophenyl (DNP) derivative of taurine . The reaction conditions are selected to allow complete derivatization of taurine within 15 min . DNP-taurine samples are stable for at least 3 days . DNP-taurine was separated by reversed-phase liquid chromatography within 12 s . The recovery of taurine was 102 +/- 3% (S.D . = 2.5%, n = 6) and the detection limit was 10 pmol for taurine (signal-to-noise ratio of 10) . The method was applied to the determination of taurine levels in different samples including marine products, infant formulas and fermentation media of different bacterial species.

Metabolism, 1994 Jun, 43(6), 728 - 34
Effect of propionate on in vivo carbohydrate metabolism in streptozocin-induced diabetic rats; Cameron-Smith D et al.; Undigested carbohydrates and some dietary fibers are fermented in the large intestine to form short-chain fatty acids (SCFA), including acetate, propionate, and butyrate . It has been suggested that some of the beneficial effects of high-carbohydrate, high-fiber diets on carbohydrate and lipid metabolism are mediated by the metabolism of SCFA in the liver . Propionate has been shown in vitro to decrease glucose production in rat hepatocytes . The aim of the present study was to investigate the effects of propionate on carbohydrate metabolism in normal and streptozocin (STZ)-induced diabetic male Sprague-Dawley rats . Rats were fed a high-fat diet with or without sodium propionate supplementation (either 0.5% or 5% wt/wt) for 4 weeks . At the completion of the feeding period, body weight and liver glycogen concentrations were significantly decreased in STZ-diabetic rats and were unaffected by propionate supplementation . Although STZ-diabetic animals had elevated fasting plasma glucose, cholesterol, and triglyceride levels relative to nondiabetic rats, propionate supplementation had no significant effect on these parameters in either group . Basal and insulin-stimulated carbohydrate metabolism were assessed using the euglycemic clamp technique in overnight-fasted animals with 3(H)-6-glucose infusion . As expected, basal hepatic glucose production (HGP) was higher and the metabolic clearance rate of glucose (MCR) was lower in STZ-diabetic rats . High-dose insulin infusion (3 mU.kg-1.min-1) suppressed HGP in nondiabetic and diabetic animals and increased the MCR in nondiabetic animals . However, propionate supplementation did not alter basal or insulin-stimulated HGP or the MCR in either nondiabetic or diabetic animals.(ABSTRACT TRUNCATED AT 250 WORDS)

J Bacteriol, 1994 Jun, 176(11), 3250 - 6
Phosphoenolpyruvate-dependent maltose:phosphotransferase activity in Fusobacterium mortiferum ATCC 25557: specificity, inducibility, and product analysis; Robrish SA et al.; Phosphoenolypyruvate-dependent maltose:phosphotransferase activity was induced in cells of Fusobacterium mortiferum ATCC 25557 during growth on maltose . The disaccharide was rapidly metabolized by washed cells maintained under anaerobic conditions, but fermentation ceased immediately upon exposure of the cell suspension to air . Coincidentally, high levels of a phosphorylated derivative accumulated within the cells . Chemical and enzymatic analyses, in conjunction with data from 1H, 13C, and 31P nuclear magnetic resonance spectroscopy, established the structure of the purified compound as 6-O-phosphoryl-alpha-D-glucopyranosyl-(1-4)-D-glucose (maltose 6-phosphate) . A method for the preparation of substrate amounts of this commercially unavailable disaccharide phosphate is described . Permeabilized cells of F . mortiferum catalyzed the phosphoenolpyruvate-dependent phosphorylation of maltose under aerobic conditions . However, the hydrolysis of maltose 6-phosphate (to glucose 6-phosphate and glucose) by permeabilized cells or cell-free preparations required either an anaerobic environment or addition of dithiothreitol to aerobic reaction mixtures . The first step in dissimilation of the phosphorylated disaccharide appears to be catalyzed by an oxygen-sensitive maltose 6-phosphate hydrolase . Cells of F . mortiferum, grown previously on maltose, fermented a variety of alpha-linked glucosides, including maltose, turanose, palatinose, maltitol, alpha-methylglucoside, trehalose, and isomaltose . Conversely, cells grown on the separate alpha-glucosides also metabolized maltose . For this anaerobic pathogen, we suggest that the maltose:phosphotransferase and maltose 6-phosphate hydrolase catalyze the phosphorylative translocation and cleavage not only of maltose but also of structurally analogous alpha-linked glucosides.

J Dairy Sci, 1994 Jun, 77(6), 1630 - 43
Blood and hydrolyzed feather meals as sources of undegradable protein in high fat diets for cows in early lactation; Palmquist DL et al.; Thirty-six cows were in a 2 x 3 factorial study during the first 2 mo of lactation to examine effects on milk yield and composition of added fat (5% of feed DM) and percentage of ruminally undegradable protein (100, 120, or 140% of recommended intake) in the diet . The main source of added undegradable protein was a 1:1 (wt/wt) mixture of blood meal:hydrolyzed feather meal . Diets were low in ADF (ca . 14%) and were highly fermentable in the rumen . The amount of intermediate dietary protein reduced feed intake . Milk yield was high (40 to 44 kg/d), similar among treatment groups, and was sustained for the entire 60-d trail . All cows yielded milk of low fat content (2.1 to 3.2%); supplemental fat decreased proportions of C6 to C14, C18:2, and C18:3 in milk fat and increased C4, C16:0, C18:0, and C18:1 . Higher dietary protein had a positive linear effect on milk fat percentage and increased C16:0 and decreased trans-C18:1 and C18:2 contents of milk fat . Added fat did not change total milk N but increased NPN as a percentage of total milk N . Percentage of total N in milk and yield of whey N was reduced when the intermediate protein diet was fed, associated with the lower DMI of this diet . A requirement for ruminally undegradable protein intake higher than recommended by NRC was not demonstrated with the highly fermentable diets fed in this study; however, ruminal acetate: propionate ratio and milk fat percentage were low.

J Dairy Sci, 1994 Jun, 77(6), 1618 - 29
Effects of amount of protein and ruminally protected amino acids in the diet of dairy cows fed supplemental fat; Christensen RA et al.; The objectives of this experiment were to investigate the effects of amount of dietary CP and ruminally protected AA supplementation on production of milk and milk components, ruminal fermentation, and nutrient digestibilities by cows fed diets containing high oil corn and tallow . Holstein cows in midlactation producing 22 to 25 kg/d of milk were used in a 5 x 5 Latin square design . Treatments were 1) control (16.8% CP, no added fat); 2) 14.2% CP, no AA; 3) 14.2% CP, with AA; 4) 17.5% CP, no AA; and 5) 17.5% CP, with AA . Diets 2 to 5 contained supplemental fat from high oil corn and tallow . Diets consisted of 33% alfalfa haylage, 17% corn silage, and 50% concentrate DM . Intake of DM was not different among treatments . Dietary fat increased yields of milk, fat, SNF, and total solids and percentages of fat and total solids . Increasing CP from 14.2 to 17.5% did not alter production or composition of milk . Supplemental AA increased yields of 4% FCM, milk fat, milk CP, true protein, and casein protein and percentages of CP, true protein, and casein protein in milk when either 14.2 or 17.5% CP was in the diet . Supplemental fat did not alter ruminal fermentation, but increases in dietary CP increased total VFA concentration in the rumen without affecting proportions of individual VFA . Apparent digestibilities of DM, OM, CP, starch, and energy in the total tract were greater for cows fed the 17.5% CP diets . Addition of AA to the 14.2% CP diet increased apparent digestibilities of DM, OM, ADF, NDF, and energy in the total tract but decreased digestibilities for cows fed the 17.5% CP diets . Feeding AA to midlactation cows in diets containing supplemental fat may alleviate the decrease in milk protein percentage associated with fat supplementation; this response was similar for cows fed diets that contained either 14.2 or 17.5% CP.

J Dairy Sci, 1994 Jun, 77(6), 1589 - 97
Effects of extruded soybeans and forage source on fermentation by rumen microorganisms in continuous culture; Illg DJ et al.; Continuous culture fermenters were used to evaluate effects of extrusion of whole soybeans and changes in forage composition of diets on microbial fermentation . Treatments were arranged in a 2 x 4 factorial design with soybeans (raw or extruded) and dietary treatment (ratio of alfalfa hay to corn silage; 82:18, 61:39, 43:57, and 27:73 of dietary forage) as main effects . Soybeans constituted 9.6, 14.4, 19.2, and 23.9% of DM for each of the respective dietary treatments . True digestion of DM, ADF, and NDF was unaffected by processing of soybeans or dietary treatment, but true digestion of OM decreased as concentration of corn silage and soybeans increased . Total VFA concentration was unaffected by source of soybeans or dietary treatments; however, molar concentration of butyrate decreased in fermenters supplied with diets containing extruded soybeans . Degradation of CP was not influenced by soybean source but decreased as the concentration of corn silage and soybeans increased . Bacterial N output decreased, and dietary N flow from the fermenters increased, as concentration of corn silage and soybeans increased . Changes in the ratio of alfalfa hay to corn silage and alteration of dietary soybean concentration affected true OM digestion and dietary CP degradation, but extrusion of whole soybeans had little effect on fermentation.

J Dairy Sci, 1994 Jun, 77(6), 1563 - 9
Influence of corn and sorghum starch on the in vitro kinetics of forage fiber digestion; Grant RJ; In vitro digestion experiments were conducted to examine the interactions of starch source and pH on kinetics and apparent extent of ruminal NDF digestion . Alfalfa hay, bromegrass hay, and each hay with either raw sorghum, raw corn, or pure corn starch in ratios to simulate a 28% NDF diet were incubated at pH 5.5, 6.2, or 6.8 . Ash-free NDF was measured at 0, 6, 12, 18, 24, 30, 36, 48, 72, and 96 h of fermentation; logarithmic transformation and linear regression were used to estimate digestion parameters . Significant forage by starch interactions on lag and rate of NDF digestion and significant forage and starch by pH interactions on rate and potential extent of NDF digestion indicated that forage type must be considered when the effect of pH and starch source on NDF digestion is predicted . For both forages, raw or pure corn starch increased lag more than sorghum starch, especially at low pH . Raw sorghum starch decreased the rate of NDF digestion more for bromegrass hay than for alfalfa hay, and pure corn starch had the largest negative impact on fiber digestion, especially at low pH . Sources of starch influenced lag and rate of NDF digestion differently at pH from 6.8 to 5.5, which led to dramatic differences in apparent extent of ruminal NDF digestion.

J Dairy Sci, 1994 Jun, 77(6), 1509 - 14
Quaternary ammonium compounds in milk: detection by reverse-phase high performance liquid chromatography and their effect on starter growth; Valladao M et al.; A reverse-phase HPLC method is described that permits detection of quaternary ammonium sanitizers in milk . The commercial mixture of quaternary ammonium sanitizer used, n-alkyl (50% C14, 40% C12, and 10% C16) dimethyl benzyl ammonium chloride, was extracted from raw and homogenized milks by the Mojonnier milk fat extraction protocol, selectively eluted from the reverse-phase column in the presence of organic solvent and ion-pairing agent, and then analyzed by diode array detection at 217 and 280 nm . Quaternary ammonium sanitizer concentrations in augmented milk samples in the range of 1.0 to 60 micrograms/ml were analyzed with high precision as indicated by a small variance around the mean . Starter culture strains currently in use for manufacture of various fermented milk products available in the Department of Microbiology Culture Collection were examined for their sensitivity to quaternary ammonium sanitizer . All strains were greatly inhibited by as little as 20 micrograms/ml in milk; some were inhibited by only 10 micrograms/ml.

J Anim Sci, 1994 Jun, 72(6), 1608 - 15
The influence of intake level and corn processing on digestibility and ruminal metabolism in steers fed all-concentrate diets; Murphy TA et al.; The effects of intake (ad libitum and 70% of ad libitum) and corn processing (whole or rolled) on digestion, ruminal metabolism, and blood metabolites were determined in a 2 x 2 factorial experiment using eight ruminally fistulated steers . All-concentrate diets were fed with adjustments to dietary concentrations of N, vitamins, and minerals to ensure equal daily intake of these nutrients . Digestion of DM, OM, and starch were affected by an intake x processing interaction (P < .03) . Starch digestion for the low-intake, whole-corn diet was much lower than that for the other three diets . This decrease in starch digestion was the major reason for the interaction . Nitrogen digestion was improved (P < .03) with limited intake but was not affected by processing . Ruminal volume and ruminal turnover (percentage/hour) were both reduced (P < .03) on the low-intake diet . Molar proportion of acetate was reduced and propionate was increased (P < .01) for steers receiving high intake of rolled corn compared with the other three diets . Butyrate concentrations were increased (P < .01) when corn was rolled before feeding . Ruminal pH was higher immediately before feeding for steers receiving whole corn than for those receiving rolled corn . Decreases in pH were observed for rolled corn 2 to 9 h after feeding, suggesting a faster rate of fermentation of rolled corn than of whole corn . Concentrations of blood glucose and insulin were not affected by intake or processing . It was concluded that processing corn can improve DM and OM digestibility if intake is restricted and that N digestion is improved with restricted feeding.(ABSTRACT TRUNCATED AT 250 WORDS)

Genetics, 1994 Jun, 137(2), 369 - 79
Reduced dosage of genes encoding ribosomal protein S18 suppresses a mitochondrial initiation codon mutation in Saccharomyces cerevisiae; Folley LS et al.; A yeast mitochondrial translation initiation codon mutation affecting the gene for cytochrome oxidase subunit III (COX3) was partially suppressed by a spontaneous nuclear mutation . The suppressor mutation also caused cold-sensitive fermentative growth on glucose medium . Suppression and cold sensitivity resulted from inactivation of the gene product of RPS18A, one of two unlinked genes that code the essential cytoplasmic small subunit ribosomal protein termed S18 in yeast . The two S18 genes differ only by 21 silent substitutions in their exons; both are interrupted by a single intron after the 15th codon . Yeast S18 is homologous to the human S11 (70% identical) and the Escherichia coli S17 (35% identical) ribosomal proteins . This highly conserved family of ribosomal proteins has been implicated in maintenance of translational accuracy and is essential for assembly of the small ribosomal subunit . Characterization of the original rps18a-1 missense mutant and rps18a delta and rps18b delta null mutants revealed that levels of suppression, cold sensitivity and paromomycin sensitivity all varied directly with a limitation of small ribosomal subunits . The rps18a-1 mutant was most affected, followed by rps18a delta then rps18b delta . Mitochondrial mutations that decreased COX3 expression without altering the initiation codon were not suppressed . This allele specificity implicates mitochondrial translation in the mechanism of suppression . We could not detect an epitope-tagged variant of S18 in mitochondria . Thus, it appears that suppression of the mitochondrial translation initiation defect is caused indirectly by reduced levels of cytoplasmic small ribosomal subunits, leading to changes in either cytoplasmic translational accuracy or the relative levels of cytoplasmic translation products.

Dtsch Tierarztl Wochenschr, 1994 Jun, 101(6), 237 - 40
{Relationships between postpartum mobilization of body substances and rumen digestion in dairy cows}; Zust J et al.; Relationships between body tissue mobilisation during the postpartal period, and rumen fermentation were studied in 105 high yielding Holstein-Friesian dairy cows . A strongly positive correlation (p < 0.001) between the molar proportion of ruminal acetic acid, and a negative correlation (p < 0.001) between the molar percentage of ruminal propionic and butyric acid (on one hand), and body tissue mobilisation as well as blood plasma concentrations of free fatty acids, beta-hydroxybutyrate, and total bilirubin (on the other hand) were found . These results indicate that in animals with higher postpartal loss of body weight, ruminobacterial fermentation activity is lower, probably secondary to metabolic disturbances.

Z Lebensm Unters Forsch, 1994 Jun, 198(6), 480 - 5
Stability of sulphadimidine during raw fermented sausage preparation; Smit LA et al.; The transformation of sulphadimidine (SDM) during raw fermented sausage preparation was studied to elucidate the SDM decrease found in an earlier study . The raw fermented sausages were prepared from batters containing 1 and 10 mg {14C}-SCM kg-1 . The sausages and the brines were analysed using methods based on solid-phase extraction followed by HPLC combined with liquid scintillation counting . It can be concluded that the decrease in SDM level is mainly caused by (i) leaching into the brine (approx . 25%), (ii) transformation of SDM, possibly by reactions with components in the sausage or the brine, as the presence of five reaction products from SDM could be demonstrated, and (iii) formation of bound residues (approx . 20%).

J Antibiot (Tokyo), 1994 Jun, 47(6), 639 - 47
Fusarium merismoides Corda NR 6356, the source of the protein kinase C inhibitor, azepinostatin . Taxonomy, yield improvement, fermentation and biological activity; Ohshima S et al.; Fungal strain NR 6356, Fusarium merismoides Corda, was discovered as the source of the protein kinase C (PKC) inhibitor, azepinostatin . The strain was identified based on its growth on potato sucrose agar, slender conidial shape, characteristic polyphialide and production of abundant chlamydospores . Fusarium aquaeductuum Lagh . IMI 103658 and Fusarium sp . NR 7222 were also found to produce the same inhibitor . After single colony isolation and medium optimization trials, a more than 30-fold increase in the production of azepinostatin over the original culture was achieved . Azepinostatin selectively and potently inhibited rat brain PKC with an IC50 value of 70 nM . Other enzymes utilizing ATP, including hexokinase, were not affected . The Ki of azepinostatin for PKC was 0.5 nM . The inhibition of PKC was competitive with ATP and uncompetitive with histone.

J Antibiot (Tokyo), 1994 Jun, 47(6), 619 - 30
WS79089A, B and C, new endothelin converting enzyme inhibitors isolated from Streptosporangium roseum . No . 79089 . Taxonomy, fermentation, isolation, physico-chemical properties and biological activities; Tsurumi Y et al.; WS79089A, B and C, which are novel endothelin converting enzyme (ECE) inhibitors have been isolated from the fermentation broth of Streptosporangium roseum No . 79089 . These inhibitors were purified from an acetone extract of whole culture broth followed by Silicar CC-4 column chromatography and HPLC . WS79089A, B and C showed highly selective ECE inhibition activity with IC50 values of 0.73 microM 0.14 microM and 3.42 microM, respectively . On the basis of spectroscopic and chemical evidence, the tentative structures of WS79089A, B and C have been proposed, they have benzo{a}naphtacen chromophores.

Rev Sci Tech, 1994 Jun, 13(2), 599 - 614
Traditional methods used for controlling animal diseases in Iran; Tadjbakhsh H; In ancient times in Iran, infectious diseases of animals and human beings were referred to as choleraic diseases . Rhazes (9th century), followed by Avicenna (10th century), Jorjani (11th century) and others, had specific opinions on the cause and effect relationship in these diseases, which recall the fermentation theory of Louis Pasteur . In ancient Iran, the methods adopted for veterinary procedures were those of general theoretical and practical medicine, including the humoral theory, accurate diagnosis, signs and symptoms, and the prescription of herbal and mineral medicines or substances of animal origin . If herbal treatment failed, cauterisation and surgery were used . When refractory and contagious infectious diseases occurred, animals were evacuated from the infected region, in order to preserve their health, with resort to the mercy of Allah (God) as a final remedy . Iranian scientists of ancient times had interesting views on rabies . A kind of serotherapy was used for treating persons bitten by rabid dogs . Vaccination was performed many centuries ago by using dried smallpox lesions . In Baluchistan (Iran), infants were encouraged to play with and touch the teats of cows affected with cowpox, in order to immunise the children against smallpox, and this was centuries before the discovery of smallpox vaccine by Edward Jenner . Camelpox was also used for human immunisation . In the case of caprine pleuropneumonia, an extract or juice was obtained from the lungs of affected animals and was inactivated by treatment with certain herbal medicines which had a disinfectant effect . A thread coated with this extract was passed through the ear of healthy goats to render them immune . The author lists various diseases and their treatment . This work forms part of detailed research by the author with reference to some 2,200 books and many ancient manuscripts on the history of veterinary science in Iran.

Br J Nutr, 1994 Jun, 71(6), 871 - 86
Effect of baked beans (Phaseolus vulgaris) on steroid metabolism and non-starch polysaccharide output of hypercholesterolaemic pigs with or without an ileo-rectal anastomosis; Costa NM et al.; The plasma-cholesterol-lowering effects of some dietary legumes are now well established from animal and human studies, but the mechanism is not completely understood . The present study investigated the effect of baked beans (Phaseolus vulgaris) on steroid metabolism of hypercholesterolaemic pigs . Three groups of four pigs were studied: baseline (BL), normal pigs (NP) and those previously prepared with an ileo-rectal anastomosis to nullify the function of the large intestine (IR) . All three groups were given a semi-purified control diet, with about 40% energy as fat (polyunsaturated:saturated fatty acid (P:S) ratio 0.3), supplemented with 10 g cholesterol/kg, for 14 d . Then IR and NP pigs were fed for 28 d on a diet supplemented with 10 g cholesterol/kg and 300 g baked beans/kg (dry-matter basis), so that the 40% contribution to energy from fat was maintained (P:S ratio 0.3) . Group BL was fed on the control diet throughout . The intact pigs (NP) fed on baked beans showed considerable differences compared with the other groups, as follows: (a) reduced plasma cholesterol (NS); (b) higher concentration of cholesterol in bile (NS); (c) higher concentration of bile acids, especially secondary bile acids, in bile (P < 0.05); (d) reduced elimination of bile acids in faeces, especially secondary bile acids (P < 0.05); (e) higher excretion of coprostanol and lower elimination of cholesterol in faeces (P < 0.05) . From these findings it is proposed that a baked-bean-enriched diet potentiates bacterial fermentation and steroid degradation in the large intestine and enhances conservation of bile acids and cholesterol within the enterohepatic circulation . The high concentration of bile acids and cholesterol in bile may thus promote feedback inhibition of hepatic cholesterol synthesis, and hence, reduce plasma cholesterol.

Eur J Biochem, 1994 Jun 1, 222(2), 615 - 23
Construction, expression and characterization of a plasmid-encoded Na(+)-specific ATPase hybrid consisting of Propionigenium modestum F0-ATPase and Escherichia coli F1-ATPase; Kaim G et al.; The Escherichia coli strain DK8, a deletion mutant lacking the complete unc operon, was transformed with a plasmid containing the genes encoding the a, b, c, delta and part of the alpha subunit of the Na(+)-dependent ATPase of Propionigenium modestum and the genes encoding the alpha, gamma, beta and epsilon subunits of the H(+)-dependent E . coli ATPase . The transformants showed Na(+)-dependent growth on succinate as non-fermentable carbon source . The functionally expressed hybrid ATPase was activated 13-fold at pH 7.5 by the addition of Na+ and inhibited by 1,3-dicyclohexylcarbodiimide, azide and tributyltin chloride . At pH 7.5 and pH 9.0, the hybrid enzyme was protected from inhibition by 1,3-dicyclohexylcarbodiimide in the presence of 50 mM NaCl and 5 mM NaCl, respectively . The hybrid ATPase was reconstituted into proteoliposomes and catalyzed the transport of Na+ upon ATP addition . ATP-dependent fluorescence quenching of 9-amino-6-chloro-2-methoxyacridine proved that the ATPase hybrid was able to pump protons in the absence of Na+ . Furthermore, ATP synthesis could be measured under conditions where a valinomycin-mediated K+ diffusion potential (delta psi) and a Na+ concentration gradient (delta p Na+) were imposed.

Yeast, 1994 Jun, 10(6), 719 - 31
A new nuclear suppressor system for a mitochondrial RNA polymerase mutant identifies an unusual zinc-finger protein and a polyglutamine domain protein in Saccharomyces cerevisiae; Brohl S et al.; A yeast strain with a point mutation in the nuclear gene for the core subunit of mitochondrial RNA polymerase was used to isolate new extragenic suppressors . Spontaneously occurring phenotypical revertants were analysed by crosses with the wild-type and tetrad dissection . One of the new nuclear suppressor mutants was characterized by temperature-sensitive growth on non-fermentable carbon sources . This mutant was transformed with a genomic yeast library . Two independent types of DNA clones were isolated which both complemented the temperature-sensitive defect . Subcloning and DNA sequencing identified two novel yeast genes which code for proteins with the characteristic features of transcription factors . Both factors exhibit highly structured protein domains consisting of runs and clusters of asparagine and glutamine residues . One of the proteins contains in addition zinc-finger domains of the C2H2-type . Therefore the genes are proposed to be named AZF1 (asparagine-rich zinc-finger protein) and PGD1 (polyglutamine domain protein) . Gene disruption of both reading frames has no detectable influence on the vegetative growth on complete glucose or glycerol media, indicating that the genes may act as high copy number suppressors of the mutant defect . Additional transformation experiments showed that AZF1 is also an efficient suppressor for the original defect in the core subunit of mitochondrial RNA polymerase.

Voen Med Zh, 1994 Jun, (6), 44 - 5, 80
{The hepatitis C problem in transfusions in military medicine}; Danil'chenko VV et al.; The article contains data on viral hepatitis C, its etiological factor, epidemiology, methods of diagnosis and prophylaxis . It's high time to conduct 100% screening control of donors for viral hepatitis C antibody, using national test system of fermental analysis . The authors worked out the method of "dry drop" to study the serum for hepatitis C virus antibody.

Eur J Clin Nutr, 1994 Jun, 48(6), 386 - 96
Dose-response effects of boiled carrots and effects of carrots in lactic acid in mixed meals on glycaemic response and satiety; Gustafsson K et al.; OBJECTIVE: To evaluate the effect of dosage on the metabolic response to vegetables added to a mixed lunch meal, and to relate the amounts to the tripartite plate model . Carrots were chosen as an example, and the carrots were blanched, frozen and boiled to include possible effects of processing and cooking . The effects of carrots steeped in lactic acid, as produced at fermentation, were also studied . DESIGN: The test meals with carrots, and the control meal without vegetables, were balanced regarding energy (2000 kJ) and digestible carbohydrates (60 g) and similar in fat (17 g) and protein (16-19 g) content . The carrot portions of 100, 200 and 300 g contained 2.9, 5.8 and 8.7 g dietary fibre respectively . The meals were served in the morning after an overnight fast and in random order . Blood samples for the analysis of blood glucose, plasma insulin and C-peptide were collected and satiety was graded until 210 min postprandially . SETTING: The study was performed at the research laboratory, Dalby Health Sciences Centre (primary care) . SUBJECTS: The 10 healthy, male volunteers, around 40 years of age, were recruited at random from the district's population list . None dropped out . RESULTS: The larger the carrot portion the lower were the glucose and insulin/C-peptide responses and the higher the satiety scores . The minimum amount causing significant effects was 200 g . According to the plate model, 200 g of boiled carrots was the most that could be included on half the plate . Addition of lactic acid to 200 g carrots augmented the effects on satiety scores and hormonal response . CONCLUSIONS: The addition of generous amounts of vegetables to a mixed meal improves the metabolic response.

Clin Invest Med, 1994 Jun, 17(3), 218 - 25
Effect of acute lactulose administration on serum acetate levels in cirrhosis; Fernandes J et al.; Lactulose has been used successfully in the treatment of portal-systemic encephalopathy but its exact mechanism of action is not known . The aim of this study was to observe the systemic effects of the colonic fermentation of an acute lactulose dose in cirrhotics and normal subjects . Six cirrhotic patients and 6 normal subjects were placed on 2 identical 2-d metabolic diets, 1 of which was supplemented with lactulose (1 g/100 kcals to a maximum of 28 g/d) . Lactulose increased colonic fermentation in cirrhotic and normal subjects as evidenced by higher breath hydrogen and serum acetate levels . The increase in serum acetate levels after lactulose compared to control was similar in cirrhotic compared to normal subjects . However, the mean serum acetate concentration in the cirrhotics was significantly greater than that in the control subjects (p = 0.039), indicating increased endogenous production, or decreased peripheral utilization of acetate by the cirrhotic liver, or both . No change was observed in blood ammonia, glucose, insulin, or free fatty acid levels with lactulose.

Appl Microbiol Biotechnol, 1994 Jun, 41(4), 373 - 7
Influence of increased dissolved oxygen concentration on productivity and selectivity in cultures of a colabomycin-producing strain of Streptomyces griseoflavus; Dick O et al.; The influence of enhanced O2 concentration on growth and formation of secondary metabolites by Streptomyces griseoflavus (strain Tu 2880) was investigated in a stirred tank and in an air-lift fermentor . At a partial pressure of O2 Po2 = 1880 mbar the growth was lowered by 50% compared to Po2 = 210 mbar, whilst substrate consumption and O2 uptake rate increased markedly . Production of the colabomycin complex reached maximum values at Po2 = 630 mbar . A similar increase of secondary metabolite formation was obtained when glycerol or acetate were fed at Po2 = 220 mbar . The portion of the derivate colabomycin A in the product mixture rose from 43% at Po2 = 210 mbar to 73% at Po2 = 1260 mbar . Since dissolved O2 concentration has a significant influence on productivity and selectivity it may be used to regulate aerobic fermentation processes.

Yakugaku Zasshi, 1994 Jun, 114(6), 401 - 13
{Development of bioactive functions in hydrangeae dulcis folium . II . Antiulcer, antiallergy, and cholagoic effects of the extract from hydrangeae dulcis folium}; Yamahara J et al.; In order to develop new bioactive functions of Hydrangeae Dulcis Folium, the fermented and dried leaves of Hydrangea macrophylla Seringe var . thunbergii Makino, effects of the methanolic extract from the crude drug on antiucler, antiallergic, cholagoic, and various pharmacological actions were investigated . Consequently, the methanolic extract was found to exhibit potent antiulcer, antiallergic, and cholagoic activities . By monitoring with these activities, it was found that the active constituents were contained in the lipophilic portion of the methanolic extract . Furthermore, the known lipophilic constituents such as phyllodulcin and hydrangenol were found to show little antiulcer and cholagoic activities, while it was also found that they showed antiallergic activity on Schultz-Dale reactions.

Arch Biochem Biophys, 1994 May 15, 311(1), 62 - 71
Regulation of pyruvate carboxylase isozyme (PYC1, PYC2) gene expression in Saccharomyces cerevisiae during fermentative and nonfermentative growth; Brewster NK et al.; In Saccharomyces cerevisiae there are two isoenzymes of pyruvate carboxylase (Pyc) encoded by separate genes, designated PYC1 and PYC2 . In the wild type yeast, the expression of both genes is influenced by both the growth phase and the type of carbon source, indicating discrete regulatory mechanisms and metabolic roles for PYC1 and PYC2 . On glucose minimal medium PYC1 and PYC2 are differentially regulated as shown by a constant level of PYC1 expression throughout the main growth phase compared to a high level of PYC2 expression only in the early growth phase . On ethanol minimal medium, the growth-related pattern of PYC1 and PYC2 expression was similar as shown by a 3.6-fold decline from early to mid log phase . PYC1 expression, however, was activated 10-fold above PYC2 mRNA levels during this period of growth . To further investigate the roles of the two PYC genes we determined the growth phenotypes and expression levels of PYC in pyc1 and pyc2 single null mutants . During fermentative growth, the lack of either PYC gene had little effect on the level and pattern of expression of the other PYC gene, indicating further their separate regulation . In comparison to the pyc2 null, the pyc1 null strain showed a 3- to 4-fold lower level of Pyc activity and Pyc protein concentration . Moreover, the pyc1 null showed a strong requirement for L-aspartate for efficient growth, indicating the importance of PYC1 expression for the synthesis of C4 intermediates . DV6.2 (PYC1, pyc2 delta) showed a 3.2-fold higher level of activity on ethanol minimal medium when compared to growth on glucose minimal medium, and supported growth in the absence of L-aspartate . The pyc1 null, MW21.3 (pyc1 delta, PYC2), on the other hand, did not support growth on ethanol in the absence of aspartate . This study represents the first report on the characterisation of expression of the PYC genes in yeast throughout growth . Their metabolic roles for both fermentative and gluconeogenic growth are considered.

FEMS Microbiol Lett, 1994 May 15, 118(3), 213 - 8
Acetaldehyde production in Saccharomyces cerevisiae wine yeasts; Romano P et al.; Eighty-six strains of Saccharomyces cerevisiae were investigated for their ability to produce acetaldehyde in synthetic medium and in grape must . Acetaldehyde production did not differ significantly between the two media, ranging from a few mg/l to about 60 mg/l, and was found to be a strain characteristic . The fermentation temperature of 30 degrees C considerably increased the acetaldehyde produced . This study allowed us to assign the strains to different phenotypes: low, medium and high acetaldehyde producers . The low and high phenotypes differed considerably also in the production of acetic acid, acetoin and higher alcohols and can be useful for studying acetaldehyde production in S . cerevisiae, both from the technological and genetic point of view.

Mol Gen Genet, 1994 May 10, 243(3), 358 - 62
Polyubiquitin gene expression contributes to oxidative stress resistance in respiratory yeast (Saccharomyces cerevisiae); Cheng L et al.; UBI4, the polyubiquitin gene of Saccharomyces cerevisiae, is expressed at a low level in vegetative cells, yet induced strongly in response to starvation, cadmium, DNA-damaging agents and heat shock . UBI4 is also expressed at a higher basal level in cells growing by respiration as compared to glucose-repressed cells growing by fermentation . This higher UBI4 expression of respiratory cultures probably helps to counteract the greater oxidative stress of respiratory growth . The effects of inactivating UBI4 on high temperature viability are more marked with respiratory cultures . Also loss of UBI4 leads to a considerably increased rate of killing of respiring cells by hydrogen peroxide, whereas the same gene inactivation has relatively little effect on the peroxide sensitivity of cells in which mitochondrial functions are repressed . This is the first study to reveal that ubiquitin levels in cells can influence their ability to withstand oxidative stress.

Leuk Res, 1994 May, 18(5), 319 - 25
Induction of proto-oncogene and cytokine expression in human peripheral blood monocytes and the monocytic cell line THP-1 after stimulation with mycoplasma-derived material MDHM; Quentmeier H et al.; Mycoplasma fermentans-derived high-molecular-weight material (MDHM) was originally described to induce differentiation of murine thymocytes to cytolytic effector T-cells by stimulating IL-6 release from adherent cells . This study shows that human peripheral blood monocytes (PBMo) also respond to MDHM with increases in IL-1 beta, IL-6 and TNF alpha expression, both at the mRNA and protein level . The induced expression of IL-1 beta and TNF alpha mRNA in the monocytic THP-1 cell line increased as quickly as in primary cells . In contrast to PBMo, THP-1 and 14 other monocytic/myeloid leukemia-derived cell lines did not secrete measurable amounts of the cytokines upon treatment with MDHM . IL-1 beta and IL-6 genes contain AP-1 binding sites as regulatory elements, the AP-1 protein being composed of c-jun and c-fos gene products . In THP-1 cells c-jun mRNA expression increased after incubation with MDHM while positive c-fos expression remained unaffected . Although these data suggest AP-1 regulated cytokine mRNA expression, results from PBMo are not in accordance with this notion . In the primary cells MDHM-induced elevation of cytokine mRNA levels was preceded by a downregulation of c-fos expression while positive c-jun expression was not modulated . c-myc mRNA expression, constitutively high in THP-1 cells, was induced in MDHM-stimulated PBMo . In conclusion, MDHM-stimulated induction of cytokine mRNA expression was accompanied by different proto-oncogene responses in PBMo and THP-1 cells . These differences may represent different regulatory pathways of the two cell systems . Alternatively, these data support the notion that neither AP-1 nor the c-myc protein are involved in the MDHM-induced increase in IL-1 beta, IL-6 or TNF alpha mRNA levels . Furthermore, the present results demonstrate clearly that mycoplasma products can have a profound impact on the activation status of eukaryotic cells.

Br J Cancer, 1994 May, 69(5), 937 - 42
Starch intake and colorectal cancer risk: an international comparison; Cassidy A et al.; Intakes of starch, non-starch polysaccharides (NSPs), protein and fat have been compared with colorectal cancer incidence in 12 populations worldwide . There were strong inverse associations between starch consumption and large bowel cancer incidence (large bowel r = -0.70, colon r = -0.76) . There was no significant relation with NSPs, although the association with large bowel cancer incidence was still significant when NSP was combined with resistant starch (RS) to give an estimate of fermentable carbohydrate (large bowel r = -0.52, colon r = -0.60) . The relationships between starch, RS and NSPs and cancer incidence remained statistically significant after adjusting for fat and protein intakes . The strong inverse associations found here suggest a potentially important role for starch in protection against colorectal cancer and correspond with the hypothesis that fermentation in the colon is the mechanism for preventing colorectal cancer . Measures of both starch and NSPs need to be included in future epidemiological studies of diet and bowel cancer.

Antimicrob Agents Chemother, 1994 May, 38(5), 1123 - 8
Effects of pentamidine isethionate on Saccharomyces cerevisiae; Ludewig G et al.; We used Saccharomyces cerevisiae as a model system in which to examine the mechanism of action of the anti-Pneumocystis drug pentamidine . Pentamidine at low concentrations inhibited S . cerevisiae growth on nonfermentable carbon sources (50% inhibitory concentration {IC50} of 1.25 micrograms/ml in glycerol) . Pentamidine inhibited growth on fermentable energy sources only at much higher concentrations (IC50 of 250 micrograms/ml in glucose) . Inhibition at low pentamidine concentrations in glycerol was due to cytostatic activity rather than cytotoxic or mutagenic activity . Pentamidine also rapidly inhibited respiration by intact yeast cells, although inhibitory concentrations were much higher than those inhibitory to growth (IC50 of 100 micrograms/ml for respiration) . Pentamidine also induced petite mutations, although only at concentrations much higher than those required for growth inhibition . These results suggest that a function essential for respiratory growth is inhibited by pentamidine and that pentamidine affects mitochondrial processes . We propose the hypothesis that the primary cellular target of pentamidine in S . cerevisiae is the mitochondrion.

J Anim Sci, 1994 May, 72(5), 1362 - 74
Ruminal digestion and glycosyl linkage patterns of cell wall components from leaf and stem fractions of alfalfa, orchardgrass, and wheat straw; Bourquin LD et al.; Samples of alfalfa, orchardgrass, and wheat straw were hand-separated into leaf and stem fractions that were subjected to in situ ruminal fermentation for various lengths of time to assess the rate and extent of degradation of cell wall neutral monosaccharides, uronic acids, acetyl groups, and hydroxycinnamic acids . A second objective was to measure the glycosyl linkage patterns of leaf and stem fractions of substrates before and after ruminal fermentation . Samples were fermented for 0, 6, 12, 24, 48, 96, and 192 h in each of two ruminally cannulated steers . In situ disappearance data were fitted to a first-order exponential equation to estimate the following substrate parameters: insoluble, potentially digestible fraction (fd), indigestible fraction (fi), and fractional rate constant of degradation of the potentially digestible fraction (k) . Leaves contained larger concentrations of crude protein and smaller concentrations of cell wall components than did stem fractions . Estimates of fi were 7.3, 39.2, 22.1, 49.3, 27.7, and 36.3 for dry matter disappearances for alfalfa leaf, alfalfa stem, orchardgrass leaf, orchardgrass stem, wheat straw leaf, and wheat straw stem, respectively . Averaged across substrates, estimates of fi for arabinose, galactose, glucose, xylose, uronic acids, acetyl groups, and p-coumaric acid were 16.5, 11.4, 14.8, 31.2, 12.8, 25.3, and 22.6% in leaf fractions and 29.5, 19.9, 37.5, 56.2, 35.0, 52.4, and 44.6% in stem fractions . Rates of digestion of all monomeric components except galactose and xylose were greater (P < .05) for alfalfa than for orchardgrass or wheat straw . Differences in digestibility of cell wall components from leaf and stem fractions were greater in alfalfa and orchardgrass than in wheat straw . Glycosyl linkage analysis indicated that xylans in leaf and stem fractions of alfalfa, orchardgrass leaf, and wheat straw stem that resisted degradation had a lower degree of substitution with acid-labile constituents (i.e., other monosaccharides) than was found in original substrates . Different rates and extents of digestion of leaf and stem fractions of forages explain part, but not all, of the observed differences in digestibilities of cell wall monomers by ruminants.

Br J Nutr, 1994 May, 71(5), 731 - 7
Breath hydrogen after ingestion of the bulk sweeteners sorbitol, isomalt and sucrose in chocolate; Lee A et al.; The effect of eating chocolate containing sugar alcohols as sweetening agents on colonic fermentation has been investigated by monitoring breath H2 levels . Levels were compared with those occurring after the consumption of normal, sugar-containing chocolate . Ten healthy volunteers aged 19 to 21 years ingested equal amounts of either sorbitol, isomalt or sucrose incorporated into standard chocolate bars . Breath H2 levels after consumption of chocolate containing either sorbitol or isomalt were significantly higher than those after consumption of chocolate containing sucrose (P < 0.001) . After consumption of chocolate containing sorbitol, double the mean estimated volume of breath H2 was produced over 6 h compared with that produced after eating chocolate containing isomalt . Taken together with results relating to the incidence of intolerance symptoms, these findings demonstrate that sorbitol is associated with greater colonic fermentation compared with isomalt.

Nutr Rev, 1994 May, 52(5), 176 - 8
Hydroxypropylmethylcellulose, viscosity, and plasma cholesterol control; Topping D; The mechanism for the lowering of plasma cholesterol by water-soluble nonstarch polysaccharides (NSP) could involve alteration of intestinal viscosity leading to attenuated fat and steroid digestion and absorption . Alternatively, there may be direct inhibition of hepatic cholesterol synthesis by short-chain fatty acids produced by large bowel bacterial fermentation . A synthetic NSP, hydroxypropylmethylcellulose (HPMC), has been shown to lower plasma low-density lipoprotein (LDL) cholesterol in humans . This polysaccharide is not fermented by the large bowel microflora and has been shown to lower the plasma and liver cholesterol in hamsters, with no change noted in hepatic sterol synthesis . In further studies with hamsters, a linear relationship has been identified between plasma cholesterol and the logarithm of hydroxymethylcellulose viscosity . Only a relatively small increment in viscosity was necessary to achieve a maximal effect, suggesting that intestinal digestion may be quite sensitive to increased NSP intake.

J Clin Microbiol, 1994 May, 32(5), 1387 - 9
Isolation of Mycoplasma species from bronchoalveolar lavages of patients positive and negative for human immunodeficiency virus; Teel LD et al.; The rates of isolation of Mycoplasma species from bronchoalveolar lavages of human immunodeficiency virus (HIV)-infected patients and HIV-negative patients were compared . Mycoplasma species were more frequently isolated from HIV-positive patients . In most cases, a known pulmonary pathogen was also identified . All samples tested negative for Mycoplasma fermentans by PCR.

J Dairy Sci, 1994 May, 77(5), 1386 - 98
Comparison of three methods for incorporation of liquid fat into diets for lactating dairy cows; Drackley JK et al.; Two experiments were conducted to determine whether method of incorporation of tallow (iodine value = 57.7) into a TMR for lactating dairy cows affected DMI, milk production or composition, ruminal characteristics, or nutrient digestibilities . In Experiment 1, 8 Holstein and 8 Jersey cows were fed diets containing 1) control, no fat; 2) fat (5% of DM) added first to the concentrate; 3) fat added first to the haylage; and 4) fat added as the last ingredient in the TMR . The DMI was lower when fat was added last to the TMR; DMI was decreased for Jerseys, but not Holsteins, when fat was added first to the concentrate . Milk production was increased, and milk fat percentage decreased, by fat supplementation, but neither differed among application methods . Milk protein percentage was decreased by fat supplementation but was decreased less when fat was added last to the TMR . Production of milk CP, true protein, and casein protein was greater when fat was first mixed with haylage or added last to the TMR . In Experiment 2, four Holstein cows with ruminal cannulas were fed the same diets . Ruminal fermentation characteristics and apparent total tract digestibilities of DM, OM, CP, NDF, ADF, and ash were not different among diets . Digestibility of total fatty acids was decreased when fat was added first to haylage or last to the TMR . Incorporation method had relatively minor effects on variables.

J Dairy Sci, 1994 May, 77(5), 1340 - 53
Influence of supplemental protein source and feeding frequency on rumen fermentation and performance in dairy cows; Robinson PH et al.; Multiparous Holstein cows in early lactation were fed a basal mixed ration of 47% (DM) alfalfa and timothy silage and 53% barley and corn concentrate twice daily for ad libitum intake at 1630 and 0600 h . Two supplemental protein sources that differed in their resistance to rumen proteolysis were fed at 9% of total DMI in either two meals per day at 1730 and 0700 h or five meals per day at 1730, 2130, 0200, 0700, and 1200 h . The study was a 4 x 4 Latin square design with six blocks of 4 cows in which one block of cows was fitted with rumen cannulas . Intakes of DM, OM, NDF, and CP were not influenced by treatments . However, cows supplemented with five meals a day tended to consume the mixed ration more rapidly after both the p.m . and a.m . feedings . Milk yield and its content of protein, fat, and lactose also were not influenced by treatments . Average rumen pH was higher, and propionate concentrations were lower, for cows supplemented with five meals, but diurnal patterns were not influenced . Propionate and rumen ammonia N concentrations were lower for cows supplemented with the more resistant protein source; however, rumen VFA, as well as soluble and peptide N concentrations, were not influenced by the type of supplemental protein . Results do not support benefits of synchronized rumen release of energy and N to overall cow production, but rather support previous research that soluble protein or peptide N, or both, may act as a pool to provide N for microbial growth at times of the day when ammonia N concentrations are very low.

J Dairy Sci, 1994 May, 77(5), 1167 - 75
A cell culture model to identify biologically active peptides generated by bacterial hydrolysis of casein; MacDonald RS et al.; Consumption of fermented dairy foods has been linked to reduced incidence of colon cancer in population groups . Recently, biologically active compounds have been isolated from these products . Bacterial proteinases, produced by dairy starter cultures, generate a variety of peptides from casein . Some of these casein-derived peptides are likely to alter intestinal cell kinetics . Effects on colon cell kinetics because of the presence of casein-derived peptides may be a mechanism through which fermented dairy foods reduce the risk of colon cancer . We have used two intestinal cell lines (IEC-6 cells, derived from normal rat intestine, and Caco-2 cells, derived from human colon adenocarcinoma) to identify casein peptides that affect intestinal cell kinetics . Cell culture media containing casein were inoculated with three commercial starter cultures and incubated for 4, 8, or 24 h . The bacteria-conditioned media were then filter-sterilized and incubated with the intestinal cells for 6 or 24 h . Rates of {3H}thymidine incorporation and cell cycle kinetics determined by flow cytometry were affected by the culture-modified media in both cell lines . The IEC-6 cells tended to reduce, and Caco-2 cells to increase, rates of cell division after exposure to the media . Intestinal cell response varied among the starter cultures . The results support the use of intestinal cell cultures to identify casein peptides generated by dairy starter cultures, which affect intestinal cell kinetics.

J Antibiot (Tokyo), 1994 May, 47(5), 536 - 40
Cytostatin, a novel inhibitor of cell adhesion to components of extracellular matrix produced by Streptomyces sp . MJ654-NF4 . I . Taxonomy, fermentation, isolation and biological activities; Amemiya M et al.; Cytostatin has been identified as a novel inhibitor of cell adhesion to components of extracellular matrix (ECM) in cultured broth of Streptomyces sp . MJ654-NF4 . Though cytostatin did not inhibit EL-4 cell adhesion to ECM components such as laminin and fibronectin; it inhibited the adhesion of B16 melanoma cells to laminin and collagen type IV but not to fibronectin . It exhibited antimetastatic activity on B16 melanoma cells in mice . The cytotoxicity of cytostatin are also reported.

J Antibiot (Tokyo), 1994 May, 47(5), 523 - 7
Aselacins, novel compounds that inhibit binding of endothelin to its receptor . I . The producing organism, fermentation and biological activity; Jackson M et al.; A radioligand test to detect inhibitors of endothelin-1 binding to its receptors in bovine atrial and porcine cerebral membranes was used to screen fungal metabolites from stationary fermentations . Inhibitory activity, observed in culture extracts of two Acremonium species, led to the discovery of aselacins A, B and C . Aselacin A inhibits binding to both membrane fractions with IC50s of approximately 20 micrograms/ml.

Appl Environ Microbiol, 1994 May, 60(5), 1687 - 9
Degradation of pyrene at low defined oxygen concentrations by a Mycobacterium sp; Fritzsche C; In a fermentor, a Mycobacterium sp . was grown on pyrene at defined oxygen concentrations in a range from 11.4 to 227 microM . The maximal growth rate (mumax = 0.057 h-1) and the dissolved oxygen half-saturation constant (KDO = 5.9 microM) were calculated . At 3.4 microM, the growth rate (mu = 0.011 h-1) was only half of what was expected from the kinetic data . Apparently, this was due to limitation of an oxygenase of pyrene degradation.

Appl Environ Microbiol, 1994 May, 60(5), 1519 - 24
Effects of particulate materials and osmoprotectants on very-high-gravity ethanolic fermentation by Saccharomyces cerevisiae; Thomas KC et al.; The effects of osmoprotectants (such as glycine betaine and proline) and particulate materials on the fermentation of very high concentrations of glucose by the brewing strain Saccharomyces cerevisiae (uvarum) NCYC 1324 were studied . The yeast growing at 20 degrees C consumed only 15 g of the sugar per 100 ml from a minimal medium which initially contained 35% (wt/vol) glucose . Supplementing the medium with a mixture of glycine betaine, glycine, and proline increased the amount of sugar fermented to 30.5 g/100 ml . With such supplementation, the viability of the yeast cells was maintained above 80% throughout the fermentation, while it dropped to less than 12% in the unsupplemented controls . Among single additives, glycine was more effective than proline or glycine betaine . On incubating the cultures for 10 days, the viability decreased to only 55% with glycine, while it dropped to 36 and 27%, respectively, with glycine betaine and proline . It is suggested that glycine and proline, known to be poor nitrogen sources for growth, may serve directly or indirectly as osmoprotectants . Nutrients such as tryptone, yeast extract, and a mixture of purine and pyrimidine bases increased the sugar uptake and ethanol production but did not allow the population to maintain the high level of cell viability . While only 43% of the sugar was fermented in unsupplemented medium, the presence of particulate materials such as wheat bran, wheat mash insolubles, alumina, and soy flour increased sugar utilization to 68, 75, 81, and 82%, respectively.

FEMS Microbiol Rev, 1994 May, 14(1), 99 - 102
Efficient use of lactose for the lac promoter-controlled overexpression of the main antigenic protein of the foot and mouth disease virus in Escherichia coli under fed-batch fermentation conditions; Neubauer P et al.; Derivatives of the lac promoter (tac, pac, rac) belong to the strongest bacterial promoters which are frequently used for the induced overexpression of foreign genes in Escherichia coli . However, their use in fermentation processes is strongly restricted because of the high cost of the inducer iso-propyl-beta-D-thiogalactopyranoside (IPTG) . The aim of this work was to investigate the possibility of using lac-derived promoters in high cell density processes resulting in a high yield of the induced recombinant protein if glucose is the main carbon and energy source . Lactose is tested as inducer of the main antigenic coat protein (VP1) of the foot and mouth disease (FMD) virus in a T7-RNA polymerase expression system . It was shown that lactose is able to induce the expression of the recombinant gene to an amount of the VP1 protein corresponding to 20% of the total cell protein.

FEMS Microbiol Rev, 1994 May, 14(1), 89 - 91
Perfusion systems for hybridoma cells based on sedimentation in chambers and Erlenmeyer flasks; Lassen KM et al.; An inclined sedimentation chamber and a modified 250-ml Erlenmeyer flask have been used as separation devices for perfusion fermentations with hybridoma cells . The maximum cell density is increased 2-16-fold compared to batch fermentations when the separation units are used . When the sedimentation chamber is used, IgG is continuously produced and the daily production is increased by a factor 3.7 compared to batch fermentation.

Bull Tokyo Dent Coll, 1994 May, 35(2), 61 - 6
pH response of human dental plaque to chewing gum supplemented with low molecular chitosan; Shibasaki K et al.; The effects of low molecular chitosan (LMCS) on pH responses of human dental plaque following exposure to fermentable carbohydrates were investigated by an ion-sensitive field-effect transistor electrode system . After the plaque pH values were minimized by direct application of 5% glucose solution or consumption of sugared caramel, the subjects started chewing the test gums containing 0 (control), 1 or 3% (w/w) LMCS for three minutes . The pH response was monitored until it recovered to over pH5.5 . In the case of the glucose solution, chewing 3% LMCS gum caused significantly more rapid pH recovery toward the resting level than did the control gum . Initial pH rising rate during gum chewing was faster with either of the two LMCS gums than with the control gum . In the case of caramel, additional effects of LMCS were observed numerically as LMCS content increased . The findings indicated that LMCS had a potential to promote recovery of plaque pH after acidogenic challenge and to maintain the plaque pH around neutrality.

Zh Mikrobiol Epidemiol Immunobiol, 1994 May-Jun, (3), 23 - 6
{The heterogeneity of populations of the Escherichia coli recombinant strain KS 1561--a producer of thermolabile enterotoxin during stab cultivation}; Martynenko LD et al.; In the process of the submerged cultivation of E . coli gene engineering strain KS 1561 carrying hybridization plasmid controlling the synthesis of thermolabile enterotoxin LT . The dissociation of the initial strain with the formation of two populations with different properties was observed . One population was characterized by the capacity of fermenting lactose and had decreased activity on the production of LT; the other population, which was lactose-negative, was capable of its increased synthesis.

Food Addit Contam, 1994 May-Jun, 11(3), 397 - 402
Investigation of the presence of biogenic amines and ethyl carbamate in kenkey made with maize and maize-cowpea mixtures as influenced by process conditions; Nout MJ et al.; Kenkey is a fermented and cooked maize dough from Ghana . The effect of manufacturing conditions, i.e . fermentation and cooking, and of protein-enrichment by cowpea addition (20% of total weight) on the occurrence of toxic microbial products, namely biogenic amines and ethyl carbamate, were investigated . The levels of biogenic amines in all-maize kenkey were very low (total amines < 60 ppm), but were significantly increased by addition of red cowpea (total amines < 200 ppm, mainly cadaverine and tyramine), and even more by white cowpea (total amines < 500 ppm, mainly putrescine and tyramine) . Histamine was absent (< 5 ppm) in all samples . The effects of fermentation and cooking were less pronounced than the influence of cowpea addition . Prolonged cooking of kenkey resulted in lower levels of putrescine, but did not significantly reduce tyramine levels . Ethyl carbamate levels were negligible (< 11 ppb) in all treatments.

Appl Microbiol Biotechnol, 1994 May, 41(3), 317 - 23
Continuous insect cell (Sf-9) culture with aeration through sparging; Wang MY et al.; The continuous growth of Spodoptera frugiperda Sf-9 cells in a 250-ml blown-glass jacketed spinner flask under a direct air sparging environment was investigated . Even at 220 ml working volume (about 90% of total volume), this spinner flask provided good mixing and oxygenation as demonstrated by a higher cell density compared with fermentor cultures . This eliminates a common limitation of the traditional spinner flask, namely much lower cell density at high working volume . Furthermore, this spinner flask has been run with Sf-9 cell culture at five different dilution rates and two different air sparging rates at steady state, demonstrating its utility in research applications where cell size, metabolic activity and environmental conditions can be constantly maintained . In addition to demonstrating the utility of the reactor, three novel points are made in this report . First, cell density in continuous cultures is increased significantly due to a high agitation rate and, especially, air sparging rate, which is seldom used in animal cell or insect cell culture . Second, there is no apparent difference in the specific death rate at two different sparging rates (0.0093 vvm and 0.0125 vvm) . Finally, we have maintained Sf-9 cells for more than 4 months in a continuous culture using a serum-free medium without loss of recombinant protein expression in infected cells.

Appl Microbiol Biotechnol, 1994 May, 41(3), 309 - 12
Influence of increased dissolved oxygen concentration on the formation of secondary metabolites by manumycin-producing Streptomyces parvulus; Kaiser D et al.; The influence of increased dissolved O2 concentrations (DOC) on cell growth and production of the secondary metabolite manumycin by a strain of Streptomyces parvulus (Tu 64) was investigated in a stirred tank fermentor . DOC is given as the O2 partial pressure (po2) in the gas phase in an equilibrium state with the liquid phase . Growth of S . parvulus was not influenced up to DOC equivalent to po2 = 1260 mbar . At po2 = 2205 mbar the maximum biomass concentration was lowered by 40% . Production of manumycin was markedly influenced by DOC and reached the maximal concentration at po2 = 315 mbar . At increased DOC three new metabolites were observed . Two of them, 64p-A and 64p-B, were identified as carboxamides, which represent the branched side chain of the manumycin molecule and a derivative with a shorter chain length . The third metabolite, 64p-C, was a manumycin derivative containing an aromatic ring system . Feeding of glycerol during the production phase increased the total yield and showed a similar effect of DOC . Since DOC has significant regulation effects on product formation and selectivity, it should be used as a major parameter in development strategies of aerobic microbial processes.

Biotechnol Prog, 1994 May-Jun, 10(3), 308 - 13
Intracellular expression of Vitreoscilla hemoglobin alters the aerobic metabolism of Saccharomyces cerevisiae; Chen W et al.; Vitreoscilla hemoglobin (VHb) has been expressed in Saccharomyces cerevisiae, and its influence on yeast aerobic metabolism has been investigated . New expression vectors were constructed to express VHb constitutively under the control of the ADH-1 promoter . The presence of VHb was shown by Western blot analysis . VHb has been shown to localize predominantly in the cytoplasm . Batch fermentation results indicated that the wild-type strain expressing VHb exhibited a shift in the carbon flux toward ethanol production, with no significant alteration in the specific growth rate . This effect was not observed if cells were grown under respiration inhibition, indicating that the metabolic effect of VHb is likely linked to respiration . Expression of VHb in the adh degrees strain MC65-2A, which produces ethanol only via a respiration-coupled pathway, revealed that ethanol production was decreased and cells reached a higher final cell density in a culture of the VHb-expressing strain . Growth enhancement due to expression of VHb was observed only during the final stage of culture growth when the acetaldehyde produced during the first growth phase was used as a substrate . This metabolic effect of intracellular VHb was seen more clearly in an acetaldehyde fed-batch fermentation in which VHb-expressing cells grew to at least 3-fold higher final cell density . These results suggest that the action of VHb is likely linked to electron transfer.

Biotechnology (N Y), 1994 May, 12(5), 494 - 9
Production, purification and immunogenicity of a malaria transmission-blocking vaccine candidate: TBV25H expressed in yeast and purified using nickel-NTA agarose; Kaslow DC et al.; We have constructed a second generation malaria transmission-blocking vaccine candidate based on Pfs25, the predominate surface protein of Plasmodium falciparum zygotes, to overcome potential production problems with the original construct . Four modifications were made: (1) addition of the last cysteine residue of the fourth epidermal growth factor like-domain of Pfs25; (2) mutagenesis of asparagine-linked glycosylation sites with glutamine rather than alanine; (3) addition of a six histidine tag at the carboxy-terminus for highly efficient purification of recombinant protein on nickel-NTA agarose; and (4) fermentation that combines continuous glucose fed-batch methodology with pH-controlled glucose addition and a terminal ethanol feed . The resulting product, TBV25H (Transmission-Blocking Vaccine based on Pfs25 with a Histidine tag), appears to be a more potent antigen and immunogen than the original construct, and the fermentation and post-fermentation processing methodology easily lend themselves to technology transfer to the ultimate users, newly industrialized countries.

J Dairy Sci, 1994 Apr, 77(4), 1070 - 83
Effects of soybean hulls and lignosulfonate-treated soybean meal on ruminal fermentation in lactating dairy cows; Mansfield HR et al.; Four Holstein cows were used in a 4 x 4 Latin square design to investigate the effects of soybean hulls and lignosulfonate-treated soybean meal on ruminal fermentation and nutrient passage to the duodenum . Diets contained 32% corn silage, 19.8% alfalfa-grass hay, and 48.2% concentrate (DM basis) . Treatments, arranged in a 2 x 2 factorial, were concentrate mixes based on 1) corn and soybean meal, 2) corn and treated soybean meal, 3) soybean hulls and soybean meal, and 4) soybean hulls and treated soybean meal . Individual protein supplements supplied 40% of dietary CP, and corn or soybean hulls constituted 28% of dietary DM . Intake of OM (mean 18.9 kg/d) was similar among treatments, but intake of NDF was 42% greater, and intake of nonstructural carbohydrate was 55% less, for cows fed soybean hulls . Passage of OM to the duodenum was similar among diets, but flow of NDF was 43% greater, and flow of nonstructural carbohydrate was 56% less, for cows fed soybean hulls . Ruminal pH was similar, but total concentrations of VFA increased 7% when soybean hulls replaced corn . Ruminal digestion of dietary CP was 15% less for cows fed treated soybean meal, but bacterial N flows were similar among treatments . Soybean hulls were digested to a similar extent as corn, but few interactions occurred between supplemental carbohydrate and protein sources.

Int J Syst Bacteriol, 1994 Apr, 44(2), 348 - 56
Luteococcus japonicus gen . nov., sp . nov., a new gram-positive coccus with LL-diaminopimelic acid in the cell wall; Tamura T et al.; A new gram-positive, nonmotile coccus is described . Strains IFO 12422T (T = type strain) and IFO 15385 in the Institute for Fermentation, Osaka, culture collection, which were isolated from soil and water, respectively, have the following chemotaxonomic characteristics: menaquinone MK-9(H4); G + C content of DNA of 67 mol%; and LL-diaminopimelic acid, alanine, glycine, and glutamic acid in a molar ratio of ca . 1:2:1:1 (type A3 gamma) . Mycolic acids are not present . The taxonomic characteristics of these organisms are different from those of previously described gram-positive, high-G + C-content cocci . The partial 16S rRNA sequence indicated that IFO 12422T represents a distinct line of descent among gram-positive bacteria with a high G + C content . The name Luteococcus japonicus gen . nov., sp . nov . is proposed . The type strain is strain IFO 12422.

Int J Syst Bacteriol, 1994 Apr, 44(2), 324 - 9
Capnocytophaga haemolytica sp . nov . and Capnocytophaga granulosa sp . nov., from human dental plaque; Yamamoto T et al.; Two new Capnocytophaga species, for which we propose the names Capnocytophaga haemolytica and Capnocytophaga granulosa, were isolated from supragingival dental plaque of adults . The phenotypic characteristics of these organisms were the same as those of the genus Capnocytophaga: gram-negative rods; CO2 requirement; gliding motility; catalase negative; oxidase negative; acids produced from D-glucose, D-maltose, D-mannose, and D-sucrose; and acetate and succinate are the major end products of glucose fermentation . In addition, the cellular fatty acid contents and menaquinones of both species were similar to the cellular fatty acid contents and menaquinones of other Capnocytophaga species . Nevertheless, the levels of DNA-DNA relatedness of the two new species to each other and to other Capnocytophaga species were less than 20% . Two notable characteristics of C . haemolytica are the presence of hemolytic activity and the lack of aminopeptidase activity . C . granulosa has granular inclusions in its cells and grows aerobically . The type strains of C . haemolytica and C . granulosa are A0404 (= JCM 8565) and B0611 (= JCM 8566), respectively.

FEMS Microbiol Lett, 1994 Apr 1, 117(2), 163 - 8
Pyruvate formate-lyase is not essential for nitrate respiration by Escherichia coli; Kaiser M et al.; Defined deletion mutants of Escherichia coli defective for the synthesis of pyruvate formate-lyase (PFL) or pyruvate dehydrogenase (PDH) were analysed in regards their growth in batch culture and their enzyme levels under fermentative and nitrate respiratory conditions . A pfl mutant proved not to be completely auxotrophic for acetate when grown anaerobically in glucose minimal medium . In contrast, a pfl aceEF double mutant exhibited an absolute requirement for acetate, indicating that PDH is the source of acetyl-CoA in the pfl mutant . Growth of both pfl and aceEF single mutants under nitrate respiratory conditions was essentially indistinguishable from the wild-type . Thus, either PFL or PDH can be used to catabolize pyruvate in nitrate-respiring cells . The activities of PFL and PDH measured after growth with nitrate are commensurate with this proposal.

Mol Gen Genet, 1994 Apr, 243(2), 207 - 14
The yeast co-activator GAL11 positively influences transcription of the phosphoglycerate kinase gene, but only when RAP1 is bound to its upstream activation sequence; Stanway CA et al.; Transcription of the yeast phosphoglycerate kinase gene (PGK) is activated by an array of nuclear factors including the multifunctional protein RAP1 . We have demonstrated that the transcriptional co-activator GAL11, which was identified as an auxiliary factor to GAL4 and which is believed to interact with the zinc finger of the trans-activator, positively influences the level of PGK transcription on both fermentable and non-fermentable carbon sources . This positive effect is only observed when the RAP1 site in the upstream activation sequence (UAS) is present, implying that GAL11 acts through RAP1 . Expression of the RAP1 gene is not reduced in the gal11 background, and in vivo footprinting shows that GAL11 does not influence RAP1 DNA-binding activity . Therefore the effect of GAL11 on PGK transcription must be mediated at the PGK UAS, presumably as part of the activation complex . It has been proposed that RAP1 may act as a facilitator of GCR1 binding at the PGK UAS and therefore it is conceivable that the target for GAL11 may in fact be GCR1 . A further implication of this study is that GAL11 can interact with proteins such as RAP1 or GCR1 that are apparently structurally dissimilar from GAL4 and other zinc finger DNA-binding proteins.

Am J Clin Nutr, 1994 Apr, 59(4), 879 - 83
Comparative study of the acute effects of resistant starch and dietary fibers on metabolic indexes in men; Ranganathan S et al.; The effect of ingestion of the same amount (30 g) of a resistant starch (lintner) and cellulose on energy expenditure (EE), colonic fermentation (breath-hydrogen test), and blood glucose, insulin, and free fatty acid (FFA) concentrations were compared in seven healthy volunteers in a first experiment . In a second experiment the same indexes were measured in six healthy volunteers after the ingestion of diets composed of 50 g glucose alone or mixed with 30 g lintner, or cellulose, or pectin . In the first experiment no differences between lintner and cellulose were observed on the measured indexes . The notable difference was the increased apparent colonic fermentation with lintner after 6 h . In experiment 2, although insulin response was significantly lower in the pectin-added diet, the results obtained with the four different diets were not significantly different . The metabolic characteristics of lintner were closer to cellulose than to pectin . In conclusion, the acute effect of the ingestion of a resistant starch (lintner) on the measured metabolic indexes is similar to that of a known insoluble fiber--cellulose.

Mol Cell Biol, 1994 Apr, 14(4), 2740 - 54
Identification and characterization of a novel yeast gene: the YGP1 gene product is a highly glycosylated secreted protein that is synthesized in response to nutrient limitation; Destruelle M et al.; Nutrient starvation in the yeast Saccharomyces cerevisiae leads to a number of physiological changes that accompany entry into stationary phase . The expression of genes whose products play a role in stress adaptation is regulated in a manner that allows the cell to sense and respond to changing environmental conditions . We have identified a novel yeast gene, YGP1, that displays homology to the sporulation-specific SPS100 gene . The expression of YGP1 is regulated by nutrient availability . The gene is expressed at a basal level during "respiro-fermentative" (logarithmic) growth . When the glucose concentration in the medium falls below 1%, the YGP1 gene is derepressed and the gene product, gp37, is synthesized at levels up to 50-fold above the basal level . The glucose-sensing mechanism is independent of the SNF1 pathway and does not operate when cells are directly shifted to a low glucose concentration . The expression of YGP1 also responds to the depletion of nitrogen and phosphate, indicating a general response to nutrient deprivation . These results suggest that the YGP1 gene product may be involved in cellular adaptations prior to stationary phase and may be a useful marker protein for monitoring early events associated with the stress response.

J Bioenerg Biomembr, 1994 Apr, 26(2), 157 - 65
Intermediate metabolism in Trypanosoma cruzi; Cazzulo JJ; Epimastigotes of Trypanosoma cruzi, the causative agent of Chagas disease, catabolize proteins and amino acids with production of MH3, and glucose with production of reduced catabolites, chiefly succinate and L-alanine, even under aerobic conditions . This "aerobic fermentation of glucose" is probably due to both the presence of low levels of some cytochromes, causing a relative inefficiency of the respiratory chain for NADH, reoxidation during active glucose catabolism, and the lack of NADH dehydrogenase and phosphorylation site I, resulting in the entry of reduction equivalents into the chain mostly as succinate . Phosphoenol pyruvate carboxykinase and pyruvate kinase may play an essential role in diverting glucose carbon to succinate or L-alanine, and L-malate seems to be the major metabolite for the transport of glucose carbon and reduction equivalents between glycosome and mitochondrion . The parasite contains proteinase and peptidase activities . The major lysosomal cysteine proteinase, cruzipain, has been characterized in considerable detail, and might be involved in the host/parasite relationship, in addition to its obvious role in parasite nutrition . Among the enzymes of amino acid catabolism, two glutamate dehydrogenases (one NADP- and the other NAD-linked), alanine aminotransferase, and the major enzymes of aromatic amino acid catabolism (tyrosine aminotransferase and aromatic alpha-hydroxy acid dehydrogenase), have been characterized and proposed to be involved in the reoxidation of glycolytic NADH.

Protein Expr Purif, 1994 Apr, 5(2), 192 - 7
Expression of human placental alkaline phosphatase in Escherichia coli; Beck R et al.; The human placental alkaline phosphatase gene was subcloned for expression in Escherichia coli . A shortened form of the alkaline phosphatase, lacking 29 C-terminal amino acids which constitute a membrane anchoring domain, is expressed to about 5% of total protein . Most of the enzyme is present in an insoluble form; however, soluble enzyme can be detected in Western blots and activity tests . The protein is located in the periplasm since its signal peptide is cleaved off . Like the wild-type enzyme, recombinant, shortened placental alkaline phosphatase is inhibited by L-phenylalanine . The amount of active enzyme can be increased by addition of magnesium but not zinc to the medium . Using optimized fermentation conditions, 11 kU of soluble and active alkaline phosphatase are produced per liter . Coexpression of potential folding aids like peptidyl-prolyl cis-trans isomerase or disulfide isomerase does not lead to an increase of soluble enzyme, either when overexpressed separately or from an operon.

Protein Expr Purif, 1994 Apr, 5(2), 105 - 11
Preparative scale culture of Escherichia coli cells expressing the human immunodeficiency virus type 1 Tat protein; McKenna MC et al.; A procedure leading to a 100-liter fermentor culture of Escherichia coli cells expressing the human immunodeficiency virus type 1 (HIV-1) trans-activator (Tat) protein is described . The effects of growth temperature and of cell density at the time of induction on the yield of Tat were investigated . Tat was identified by SDS-gel electrophoresis and Western blot . Tat represents approximately 10% of the soluble protein in the cell lysate.

Scand J Gastroenterol, 1994 Apr, 29(4), 309 - 12
Acetaldehyde and ethanol production by Helicobacter pylori; Salmela KS et al.; By virtue of possessing alcohol dehydrogenase activity, cytosol prepared from Helicobacter pylori produces toxic acetaldehyde from ethanol in vitro . To approach the in vivo situation in the stomach, we have now investigation whether intact H . pylori--without addition of exogenous nicotinamide adenine dinucleotide--also forms acetaldehyde . Furthermore, to assess the energy metabolism of H . pylori, we determined whether the alcohol dehydrogenase-catalyzed reaction can run in the opposite direction with ethanol as the end-product and thereby yield energy for the organism . Intact H . pylori formed acetaldehyde already at low ethanol concentrations (at 0.5% ethanol, acetaldehyde, 64 +/- 21 and 75 +/- 9 mumol/l (mean +/- SEM) for strains NCTC 11637 and NCTC 11638, respectively) . H . pylori produced ethanol in concentrations that can be significant for the energy metabolism of the organism . Acetaldehyde production by H . pylori may be an important factor in the pathogenesis of gastroduodenal diseases associated with the organism . The primary function of H . pylori alcohol dehydrogenase may, however, be alcoholic fermentation and consequent energy production under microaerobic conditions.

J Clin Microbiol, 1994 Apr, 32(4), 897 - 902
Hybridization of strains of Escherichia coli O157 with probes derived from the eaeA gene of enteropathogenic E . coli and the eaeA homolog from a Vero cytotoxin-producing strain of E . coli O157; Willshaw GA et al.; A total of 375 Escherichia coli O157 strains were tested by colony hybridization with the eae probe from the central portion of the eaeA gene of the classical enteropathogenic E . coli strain E2348/69 . They were also tested with a probe, eaeO157, from the C-terminal end of the eae gene homolog from a Vero cytotoxin (VT)-producing strain of E . coli (VTEC) of serotype O157:H7 . Both probes hybridized with all 246 O157:H7 or H- VTEC strains tested . The majority were from human infections, and the remainder were from cattle . A further 10 strains (H7 or H-) hybridized with both eae and eaeO157 sequences but not with VT probes . They resembled O157 VTEC and were probably naturally occurring derivatives that had lost VT genes . The remaining 119 strains of O157 were from human, animal, and food sources and belonged to 16 H types other than H7 or were H- . They were VT negative and differed in their properties from O157 VTEC: generally they fermented sorbitol in 1 day, produced beta-glucuronidase, and could not be phage typed by the scheme for O157 VTEC . The eae probe but not the eaeO157 sequence hybridized with 18 H8 or H39 strains, predominantly from human diarrhea . The remaining 101 VT-negative strains hybridized with neither probe . However, 16 strains of O157:H45 hybridized with a probe for diffusely adherent E . coli and attached to HEp-2 cells in a diffuse pattern . Serogroup O157 comprises strains with heterogeneous properties . The eaeO157 probe is a valuable addition to the VT probes used to differentiate O157 strains.

J Clin Microbiol, 1994 Apr, 32(4), 1101 - 3
Antibiotic susceptibilities of AIDS-associated mycoplasmas; Poulin SA et al.; Because mycoplasmas may be a cofactor in the progression of human immunodeficiency virus infection to AIDS, their susceptibilities to antibiotics need to be known in the event that appropriate therapy is required . The mycoplasmas studied were a stock culture strain of Mycoplasma fermentans, two strains of M . fermentans isolated from patients with AIDS, M . fermentans var . incognitus, Mycoplasma penetrans, and Mycoplasma pirum . The antibiotics tested were doxycycline, tetracycline, clindamycin, ofloxacin, erythromycin, azithromycin, and clarithromycin at levels consistent with the attainable levels in serum . By the macrodilution metabolic inhibition method, all six mycoplasma strains were susceptible to doxycycline, tetracycline, clindamycin, ofloxacin, azithromycin, and clarithromycin . M . penetrans was susceptible to erythromycin . The M . fermentans strains and M . pirum were resistant to erythromycin . The macrodilution metabolic inhibition method results showed agreement with the Sensititre Gram Positive MIC Panel results for tetracycline, clindamycin, and erythromycin . MICs of clarithromycin for all six mycoplasma isolates tested were low, indicating susceptibility.

J Nat Prod, 1994 Apr, 57(4), 541 - 4
Secondary metabolites by chemical screening, 26.1 7-O-beta-D-galactosyl-brefeldin A via transglycosylation with Penicillium brefeldianum; Grabley S et al.; A lactose-containing fermentation medium initiated the formation of 7-O-beta-D-galactosyl-brefeldin A {1} in the brefeldin A-producing organism, Penicillium brefeldianum . The detection, isolation, and physicochemical properties of 1, which has been produced by biological derivatization via transglycosylation, are described . Compound 1 is the first glycosylated brefeldin A derivative to have been prepared.

Appl Environ Microbiol, 1994 Apr, 60(4), 1087 - 92
Pentose utilization by the ruminal bacterium Ruminococcus albus; Thurston B et al.; Ruminococcus albus is an important fibrolytic ruminal bacteria which degrades hemicellulose and ferments the resulting pentose sugars . However, little information is available on the utilization of pentoses by this organism or the effect of hexose sugars on pentose metabolism . Enzymatic studies indicated that R . albus metabolized pentoses via the pentose phosphate pathway and possessed constitutive transketolase activity . Cellobiose was preferred over xylose and arabinose, and it appeared that the disaccharide decreased pentose metabolism by repression of transport activity and catabolic enzymes (isomerases and kinases) . Glucose and xylose were co-utilized, and transport studies suggested that there was a common transport system for both sugars . In contrast, glucose was preferred over arabinose and the hexose noncompetitively inhibited the transport of arabinose . Since R . albus lacks a glucose phosphotransferase system, the inhibition of arabinose uptake could not be explained by previously described models of inducer exclusion involving such a system . Because accumulation of radiolabeled xylose, arabinose, and glucose proceeded in the absence of a proton motive force and since transport was correlated with the intracellular ATP concentration, it appeared that monosaccharide uptake was driven by ATP hydrolysis.

J Anim Sci, 1994 Apr, 72(4), 1038 - 42
Influence of yucca extract on ruminal metabolism in cows; Wu Z et al.; Two trials were conducted to determine the influence of yucca extract on ruminal digestion, fermentation, and ammonia patterns using ruminally and duodenally cannulated dairy cows . In Trial 1, urea at 0 or 1% of the diet and yucca extract at 0 or 4 g/d formed four dietary treatments in a 2 x 2 factorial arrangement . The experimental design was a 4 x 4 Latin square with 15-d periods . Duodenal digesta were sampled every 6 h during the last 4 d of each period to determine OM and ADF digestibilities and bacterial protein synthesis in the rumen using Cr2O3 and 15N markers . Ruminal digestibilities were (percentage): OM 46.3 vs 43.0%, and ADF 35.9 vs 41.4%, with or without Deodorase . Microbial protein entering the duodenum averaged 2.7 vs 3.1 kg/d for the respective treatments . Ruminal measurements were not affected by treatment (P > .10) . In Trial 2, five cows were used in a 5 x 5 Latin square with 7-d periods . Treatments were 0, 2, 4, 6, and 8 g/d of yucca extract administered via ruminal cannulas . Ruminal fluid was sampled 0, 1, 2, 4, 7, 11, 16, and 22 h after feeding during the last 2 d of each period . Average ruminal NH3 N ranged from 31.4 to 35.4 mg/dL, pH 5.99 to 6.18, and total VFA from 120 to 129 mM, and all did not differ among treatments (P > .10) . Yucca extract administered at 4 g/d did not significantly affect ruminal digestibilities of OM and ADF, and up to 8 g/d did not affect ruminal NH3, pH, or VFA.

Mol Biochem Parasitol, 1994 Apr, 64(2), 253 - 60
Entamoeba histolytica has an alcohol dehydrogenase homologous to the multifunctional adhE gene product of Escherichia coli; Yang W et al.; Entamoeba histolytica ferments glucose to ethanol under the anaerobic conditions of the human colon . There is special interest in this metabolic pathway because it provides an opportunity for parasite-specific chemotherapy . Peptide sequences from a 97-kDa E . histolytica protein, which was originally isolated because of extracellular matrix binding properties, were used to clone and sequence a gene that was found to encode an E . histolytica alcohol dehydrogenase and acetaldehyde dehydrogenase (EhADH2) . The EhADH2 cDNA clone had an open reading frame encoding 870 amino acids with a predicted molecular weight of 95,758 . The EhADH2 cDNA clone was identical in 48% of its amino acids to the multifunctional enzyme (alcohol dehydrogenase, acetyl-CoA reductase, and pyruvate-formate-lyase-deactivase) encoded by the Escherichia coli adhE gene . The isolation of the EhADH2 protein helps define a new family of ADH enzymes that may be specific to anaerobic and facultatively anaerobic organisms.

Antibiot Khimioter, 1994 Apr, 39(4), 16 - 22
{Sorption of aminoglycoside antibiotics from unfiltered culture fluid}; Bulycheva MS et al.; Sorption of aminoglycosides such as sisomicin, gentamicin, kanamycin and streptomycin from the non-filtrated fermentation broth by carboxylic cation exchange resins under the static conditions was studied . The optimal conditions for the sorption of the aminoglycosides and their subsequent desorption were determined (the ratio of the volumes of the sorbent and fermentation broth and the time of the sorption and desorption).

Bioseparation, 1994 Apr, 4(2), 89 - 99
E . coli penicillin acylase isolation by selective release, aqueous two-phase partitioning and ultrafiltration; Guan Y et al.; A procedure has been developed for the purification of penicillin acylase from E . coli fermentation broths . The method described is based primarily on selective release from biomass, charge-directed partitioning in an aqueous two-phase system, and the use of ultrafiltration membranes to recycle the modified polyethylene glycol required and to further purify the enzyme . Each step has been discussed and comparisons have been made with other approaches, where possible . Suggestions have been made for optimisation in process engineering . The approach developed may be applicable to other beta-lactam antibiotic acylases or more generally to some of the other E . coli periplasmic proteins.

Biosci Biotechnol Biochem, 1994 Apr, 58(4), 627 - 30
High level expression of Fusarium alkaline protease gene in Acremonium chrysogenum; Morita S et al.; We transformed Acremonium chrysogenum with the genomic DNA of the alkaline protease (Alp) from Fusarium sp . S-19-5 including its promoter . Most of the transformants thus obtained produced a large amount of Alp . PCR and Southern hybridization analysis of genomic DNAs from these transformants showed chromosomal integration of the full-length Alp gene . SDS-PAGE analysis of the supernatant from the transformants showed the presence of Fusarium Alp . The amino terminus of the Alp produced in A . chrysogenum was identical to that of native Fusarium Alp . These results indicate that the Alp promoter, signal sequence, and introns functioned correctly in A . chrysogenum . One of the transformants produced more than 4 g of the Alp per liter in a jar fermentor.

J Antibiot (Tokyo), 1994 Apr, 47(4), 391 - 8
WIN 64821, a novel neurokinin antagonist produced by an Aspergillus sp . I . Fermentation and isolation; Sedlock DM et al.; WIN 64821, a nonpeptide neurokinin antagonist, was isolated from a strain of Aspergillus sp., SC319 . The compound was produced in different fermentation media with greatest yields observed when the culture was grown in a synthetic medium supplemented with L-tryptophan and L-phenylalanine . After 6 days fermentation, yields greater than 600 mg/liter were obtained . Two analogs of WIN 64821 were also identified in the culture extracts and subsequently tested for biological activity . WIN 64821 was the most potent compound isolated from this culture and exhibited activity as a substance P-binding inhibitor with submicromolar potency against the human neurokinin 1 receptor.

Brain Res, 1994 Mar 28, 641(1), 51 - 6
Mycoplasma triggering of nitric oxide production by central nervous system glial cells and its inhibition by glucocorticoids; Brenner T et al.; The same cytokines that have been implicated in the pathology of central nervous system (CNS) inflammatory diseases and demyelinating diseases are also associated with the induction of nitric oxide (NO) production by macrophages and other somatic cells . Recently we have showed that mycoplasma can trigger the production of tumor necrosis factor (TNF)alpha and eicosanoids in rat astrocytes . In the present study, the effect of mycoplasma on NO production in rat glial cells was assessed . The addition of 10 micrograms/ml of membranes derived from M . capricolum (sheep isolate), M . fermentans (human isolate), or lipopolysaccharide (LPS) led to a 15- to 20-fold increase in NO production . The glucocorticoids dexamethasone and corticosterone, but not progesterone, markedly inhibited NO production . The addition of glucocorticoid prior or conjointly with the activator prevented large amounts of NO from being formed . Even when glucocorticoids were added 5 or 24 h after activation, effective inhibition of NO production was obtained . Thus, it is likely that glucocorticoids exert some of their ameliorating effects in neurological diseases by reducing the production of NO, cytokines and prostaglandins in the CNS.

J Biol Chem, 1994 Mar 25, 269(12), 9045 - 51
Deletion of the receptor MOM19 strongly impairs import of cleavable preproteins into Saccharomyces cerevisiae mitochondria; Moczko M et al.; The mitochondrial outer membrane proteins MOM19 and MOM72 are thought to function as import receptors for nuclear encoded preproteins . Different views exist about the importance of each receptor in the import of cleavable and noncleavable preproteins into mitochondria . Here we cloned and sequenced MOM19 from Saccharomyces cerevisiae and constructed a gene disruption mutant . Yeast cells lacking MOM19 were unable to grow on nonfermentable carbon sources and were slow in growing on a fermentable medium, while the growth of yeast cells lacking MOM72 (Mas70p) was much less impaired . delta MOM19 cells accumulated considerable amounts of mitochondrial preproteins in vivo . The import of cleavable preproteins into isolated delta MOM19 mitochondria was strongly inhibited, while import of the noncleavable ADP/ATP carrier and phosphate carrier was only slightly inhibited . The reciprocal situation was found for protein import into delta MOM72 mitochondria . In particular, import of the cleavable precursor of cytochrome c1 into delta MOM72 mitochondria was, in agreement with a previous report (Hines, V., and Schatz, G . (1993) J . Biol . Chem . 268, 449-454), found to be partially inhibited, yet a much stronger inhibition of import was seen into delta MOM19 mitochondria . The direct comparison of protein import into yeast mutants of either receptor yields a unifying hypothesis on mitochondrial preprotein targeting; both receptors have an overlapping specificity, and MOM19 plays a major role for cleavable preproteins . Interestingly, the primary sequence of MOM19 predicts the presence of a tetratricopeptide motif that was also found in MOM72, in the peroxisomal membrane protein PAS8/PAS10, and in several proteins involved in RNA synthesis or mitosis.

Biochem J, 1994 Mar 15, 298 Pt 3, 719 - 25
Periplasmic expression of human interferon-alpha 2c in Escherichia coli results in a correctly folded molecule; Voss T et al.; Human interferon-alpha 2c (IFN-alpha 2c) was produced in Escherichia coli under the control of the alkaline phosphatase promoter using a periplasmic expression system . Compared with other leader sequences, the heat-stable enterotoxin II leader of E . coli (STII) resulted in the highest rate of correct processing as judged by Western-blot analysis . The fermentation was designed as a batch-fed process in order to obtain a high yield of biomass . The processing rate of IFN-alpha 2c could be increased from 25% to more than 50% by shifting the fermentation pH from 7.0 to 6.7 . IFN-alpha 2c extracted from the periplasm was purified by a new four-step chromatographic procedure . Whereas cytoplasmically produced IFN-alpha 2c does not have its full native structure, IFN-alpha 2c extracted from the periplasm was found to be correctly folded, as shown by c.d . spectroscopy . Peptide-map analysis in combination with m.s . revealed the correct formation of disulphide bridges . N-terminal sequence analysis showed complete removal of the leader sequence, creating the authentic N-terminus starting with cysteine.

J Biol Chem, 1994 Mar 4, 269(9), 6664 - 70
Transcriptional modulation by n-butyric acid of beta 1-, beta 2-, and beta 3-adrenergic receptor balance in 3T3-F442A adipocytes; Krief S et al.; 3T3-F442A adipocytes, which express major beta 3-adrenergic receptors (beta 3-AR) (90%) and minor beta 1-AR (< 10%) and beta 2-AR (< 1%) populations, were used to investigate regulation by n-butyric acid of beta-AR subtype expression . Following butyrate treatment, EC50 values of beta 1- and beta 2-selective agonists, dobutamine and fenoterol, were decreased, whereas that of the beta 3-selective agonist BRL37344 was increased . Direct binding and competition of (-)-{125I}iodocyanopindolol binding by selective beta 1- and beta 2-AR antagonists, CGP20712A and ICI118551, and by the beta 3-AR agonist, BRL37344, revealed that both beta 1- and beta 2-AR were increased in butyrate-treated adipocytes, whereas beta 3-AR almost totally disappeared . In control adipocytes, beta 1-, beta 2-, and beta 3-AR transcripts (quantitated by a polymerase chain reaction assay) represented 6.5, 0.5, and 93% of total beta-AR mRNA, respectively . In butyrate-exposed cells, proportions of beta-AR proteins and mRNAs were, respectively, 87 and 94% for beta 1 and 9 and 1% for beta 2-AR . beta 3-ARs were barely detectable in binding assays and accounted for 4.5% of beta-AR transcripts . Variations of beta-AR protein and mRNA levels were accompanied by parallel changes in the transcription rates of the corresponding genes . The differential regulation of the three beta-ARs by n-butyric acid, a dietary factor produced from colonic fermentation, may have significant nutritional and energetic consequences.

Blutalkohol, 1994 Mar, 31(2), 76 - 9
{Ethanol content of Kefir water}; Rabl W et al.; The question of the influence of kefir on blood-alcohol-level has been asked in a legal proceeding . The questioned recipe consisted of 21 water, 6 soup-spoons of kefir granules (about 120 g), 150 g sugar, 2 figs and one lemon . The consumption took place after two days of fermentation . Experimentally we found, that one liter of this kefir product may contain up to 38 g/l ethanol after 7 to 10 days . On the second day we measured up to 16 g/l ethanol . Our results may be import for expert appraisements concerning unability of driving.

J Nat Prod, 1994 Mar, 57(3), 363 - 8
New teleocidin-related metabolites, (-)-7-geranylindolactam V and blastmycetin F, from Streptoverticillium blastmyceticum; Irie K et al.; Two new teleocidin-related metabolites, (-)-7-geranylindolactam-V {2} and blastmycetin F {3}, were isolated from fermentation broths of the actinomycete Streptoverticillium blastmyceticum NA34-17, and their structures were determined by spectroscopic methods . Compound 2 bound strongly to phorbol ester receptors in a mouse epidermal particulate fraction, suggesting that it is a potent in vivo tumor promoter comparable to teleocidins A-1 {4} and B-4 {5}.

Appl Biochem Biotechnol, 1994 Mar, 44(3), 231 - 42
Xylanolytic enzyme production by an Aspergillus niger isolate; Costa-Ferreira M et al.; Production of xylanolytic enzymes by an Aspergillus niger CCMI 850 isolate was investigated in batch cultures . The effect of the composition of a fermentation medium that did not include chemical inducers, on beta-xylanase, beta-xylosidase, alpha-L-arabinofuranosidase, and total cellulase activity was studied . With 4% xylan as the carbon source, about 65 U/mL of beta-xylanase was obtained, whereas the total cellulase activity was undetectable, under the specified conditions . This beta-xylanase activity represents the highest reported for a wild-type strain of A . niger . The effect of pH and temperature on the activity of beta-xylanase was studied . Partial characterization of the beta-xylanase showed that with insoluble birchwood as substrate the Km and Vmax were 0.3 mM and 19 mumol/min, respectively . Aspects of using the crude beta-xylanase preparation for applications in the pulp and paper industry were discussed.

Eur J Clin Nutr, 1994 Mar, 48(3), 151 - 63
Bioavailability of starch in bread products . Postprandial glucose and insulin responses in healthy subjects and in vitro resistant starch content; Liljeberg H et al.; Attempts to reduce glycaemia to bread were evaluated in healthy subjects . The contents of in vitro resistant starch (RS) were also measured in the bread products . The potential of including intact barley kernels at different concentrations (80% and 40%) was tested in two products (SCB-80 and SCB-40) . Three variants of barley bread made from wholemeal were also studied: ordinary (WMB), sourdough fermented (WMB-s) and one made from scalded flour (SWMB) . A commercial pumpernickel bread (PB) based on sourdough fermented rye kernels was included for comparison and a white wheat bread (WWB) used as reference for calculation of glycaemic index . The glycaemic and insulinaemic indices for SCB-80 were 33 and 39, and for PB 69 and 61, respectively . The glycaemic index was lowered also in case of SCB-40 (66) . No differences in indices were found between the WMB products or versus WWB . A high content of RS (8% starch basis) was found in the PB product, compared with the remaining bread products (0.8-1.7%).

Jpn J Cancer Res, 1994 Mar, 85(3), 298 - 305
Development and characterization of chimeric anti-carcinoembryonic antigen monoclonal antibodies and their Fab fragments; Kamigaki T et al.; In an attempt to reduce the immunogenicity of two different murine anti-carcinoembryonic antigen (CEA) monoclonal antibodies (MAbs), KM10 and A10, we produced recombinant mouse/human chimeric MAbs and the respective Fab fragments carrying the variable regions of the murine MAbs . Chimeric A10 Fab fragment was expressed in Escherichia coli, and produced in large quantities in a mini-jar fermentation system . In competitive binding assays, chimeric MAbs and their Fab fragments showed identical specificity to human CEA epitopes, as compared to the parental MAbs or Fab fragments . Both chimeric Fab fragments exhibited strong immunohistochemical reactivity with various gastrointestinal carcinomas and no reactivity with CEA-related antigens, such as NCA (nonspecific cross-reacting antigen) or BGPI (biliary glycoprotein I) . Furthermore, chimeric KM10 MAb elicited substantially higher antibody-dependent cellular cytotoxicity than the murine MAb . Complement-dependent cytotoxicity in vitro was much weaker with chimeric KM10 MAb . These results indicate that chimeric MAbs or Fab fragments could potentially replace the parental murine antibodies or their Fab fragments in therapy or diagnosis of human gastrointestinal carcinomas.

J Anim Sci, 1994 Mar, 72(3), 759 - 67
Forage level and particle size effects on orchardgrass digestion by steers: II . Ruminal digestion kinetics of cell wall components; Bourquin LD et al.; Four steers (502 +/- 49 kg) with ruminal cannulas were used in a 4 x 4 Latin square experimental design with a 2 x 2 factorial arrangement of treatments to determine the effects of the dietary forage:concentrate ratio (96:4 and 60:40) and forage particle size (long hay and coarsely ground hay) on in situ ruminal digestion kinetics of orchardgrass hay DM and cell wall neutral monosaccharides, uronic acids, acetyl groups, and hydroxycinnamic acids . Dacron in situ bags containing orchardgrass hay were fermented for 0, 4, 8, 12, 18, 24, 48, and 96 h . Digestion profiles of DM and cell wall monomers in undigested residues recovered from the rumen were analyzed using a first-order, exponential equation to estimate the indigestible fraction (fi), the insoluble, potentially digestible fraction (fd), and the fractional rate constant (kd) of digestion of fd . Initial results indicated that fi was not consistently influenced by diet fed to the steers; thus, in situ digestion profiles were analyzed to estimate single fi and fd values common to all steers and diets and different estimates of kd for each steer x diet combination (16 total) . Estimates of fi (percentage of original) for cell wall components were ranked in the following order: galactose (12.6), ferulic acid (13.9), arabinose (14.5), total uronic acids (15.4), glucose (19.8), xylose (28.4), p-coumaric acid (34.6), and acetyl groups (35.8).(ABSTRACT TRUNCATED AT 250 WORDS)

Microbiol Rev, 1994 Mar, 58(1), 56 - 70
Control of meiotic gene expression in Saccharomyces cerevisiae; Mitchell AP; Sporulation of the yeast Saccharomyces cerevisiae is restricted to one type of cell, the a/alpha cell, and is initiated after starvation for nitrogen in the absence of a fermentable carbon source . More than 25 characterized genes are expressed only during sporulation and are referred to as meiotic genes or sporulation-specific genes . These genes are in the early, middle, and late expression classes . Most early genes have a 5' regulatory site, URS1, and one of two additional sequences, UASH or a T4C site . URS1 is required both to repress meiotic genes during vegetative growth and to activate these genes during meiosis . UASH and the T4C site also contribute to meiotic expression . A different type of site, the NRE, is found in at least two late genes . The NRE behaves as a repression site in vegetative cells and is neutral in meiotic cells . Many regulatory genes that either repress or activate meiotic genes have been identified . One group of regulators affects the expression of IME1, which specifies a positive regulator of meiotic genes and is expressed at the highest levels in meiotic cells . A second group of regulators acts in parallel with or downstream of IME1 to influence meiotic gene expression . This group includes UME6, which is required both for repression through the URS1 site in vegetative cells and for IME1-dependent activation of an upstream region containing URS1 and T4C sites . IME1 may activate meiotic genes by modifying a UME6-dependent repression complex at a URS1 site . Several additional mechanisms restrict functional expression of some genes to meiotic cells . Translation of IME1 has been proposed to occur only in meiotic cells; several meiotic transcripts are more stable in acetate medium than in glucose medium; and splicing of MER2 RNA depends on a meiosis-specific gene, MER1.

J Antibiot (Tokyo), 1994 Mar, 47(3), 342 - 8
167-A, a new antibiotic produced by a mutant of an inactive wild strain of Amycolata autotrophica; Malkina ND et al.; Two related antibiotics, 167-A and 167-B, were isolated from the fermentation broth of a mutant of an inactive wild strain of Amycolata autotrophica . Antibiotic 167-B was found to be cervinomycin A2; antibiotic 167-A is a new representative of the same group and has the structure of 18-O-demethyl cervinomycin A2.

J Antibiot (Tokyo), 1994 Mar, 47(3), 289 - 93
BE-23372M, a novel protein tyrosine kinase inhibitor . I . Producing organism, fermentation, isolation and biological activities; Okabe T et al.; BE-23372M, a novel protein tyrosine kinase inhibitor, was isolated from the culture broth of a fungus . The producing strain, F23372, was identified as Rhizoctonia solani, based on the cultural and morphological characteristics . The active principle was extracted from the mycelium with acetone and purified by solvent extraction, silica gel column chromatography and Sephadex LH-20 column chromatography . BE-23372M showed strong inhibitory activity against EGF receptor kinase with IC50 values of 0.02 and 0.03 microM on two different substrates, whereas IC50 values against protein kinase C and cAMP-dependent protein kinase were 4.5 and > 20 microM, respectively . The compound inhibited the growth of A431 human epidermoid carcinoma and MKN-7 human stomach cancer cell lines with IC50 values of 8 and 24 microM, respectively.

J Antibiot (Tokyo), 1994 Mar, 47(3), 269 - 75
RES-701-1, a novel and selective endothelin type B receptor antagonist produced by Streptomyces sp . RE-701 . I . Characterization of producing strain, fermentation, isolation, physico-chemical and biological properties; Morishita Y et al.; RES-701-1, a novel cyclic peptide endothelin antagonist, was isolated from the culture broth of Streptomyces sp . RE-701 . RES-701-1 selectively inhibited the ET-1 binding to type B endothelin receptor (ETB receptor) with an IC50 of 10 nM expressed in CHO cells and blocked the ET-1-induced elevation of intracellular free Ca2+ concentration in ETB receptor-expressing COS-7 cells . Characterization of producing strain, fermentation, isolation, structure, physico-chemical and biological properties of RES-701-1 are described.

Br J Nutr, 1994 Mar, 71(3), 389 - 400
Effects of feeding restriction and meal pattern of a sugar beet-containing diet and control diet on nutrient digestibility, plasma lipid concentrations and postprandial triacylglycerol response in broiler chickens; Razdan A et al.; Broiler chickens were fed on a control diet based on maize or a diet containing sugar-beet-pulp fibre (Beetfiber) at an inclusion level of 46 g/kg . Diets were provided ad lib . or at a restricted level either once daily or three times daily . On days 13 and 20, chickens fed on the ad lib . control and sugar-beet-pulp-containing diets generally weighed more and had poorer feed conversion ratios than chickens given the restricted control and sugar-beet-pulp-containing diets respectively . Furthermore, chickens given the restricted diets once daily had greater body weights and generally improved feed conversion efficiencies compared with chickens given the restricted diets three times daily . Generally, elevated plasma lipid concentrations were observed amongst chickens given the restricted diets once daily compared with chickens fed ad lib . as well as the restricted diets three times daily, while chickens fed on restricted diets three times daily had plasma lipid concentrations intermediate between those fed ad lib . and once daily . In a plasma triacyglycerol response study on day 22, feeding of sugar-beet-pulp-containing diets generally reduced postprandial triacylglycerol concentrations and delayed triacylglycerol response relative to chickens given the control diets either ad lib . or restricted, which may indicate gastrointestinal adaptation to feeding of a fibre-rich diet . Postprandial triacylglycerol concentrations observed for chickens receiving restricted diets were increased compared with chickens given the respective ad lib . diets, indicating adaptation of chickens to reduced feed frequency . On day 25, feeding of sugar-beet-pulp-containing diets decreased digesta dry matter content and ileal organic matter digestibility . Chickens given sugar-beet-pulp-containing diets generally had, on day 25, increased caecal short-chain fatty acid (SCFA) concentrations in comparison with chickens given the ad lib . control diet, indicating increased fermentation of dietary components . It is also noteworthy that the greatest SCFA concentrations were observed amongst chickens given the control diet once daily, suggesting enhanced caecal fermentation capacity . This may have been a consequence of increased bacterial activity and caecal hypertrophy due to infrequent feeding of a low-fibre diet.

J Dairy Sci, 1994 Mar, 77(3), 789 - 98
Digestibility and effects of three forms of mostly saturated fatty acids; Elliott JP et al.; Four nonlactating Holstein cows fitted with ruminal cannulas were used in a 4 x 4 Latin square design with 14-d periods . Treatments were 1) control, no added fat; 2) 5.0% prilled fatty acids (iodine value = 14); 3) 5.6% prilled hydrogenated tallow (iodine value = 8); and 4) 5.0% flaked fatty acids (iodine value = 14) . Diets consisted of alfalfa haylage, corn silage, and concentrate (40:20:40, DM basis) . Intake of the TMR (16.4% CP and 25.4% ADF) was restricted to 1.5% of BW so that DMI was similar among diets (9.2 kg/d) . Total fatty acid intakes averaged 293, 749, 747, and 686 g/d for treatments 1 to 4, respectively . Digestibilities of total C16, total C18, and total fatty acids were greater for prilled fatty acids than for prilled hydrogenated tallow . Total tract apparent digestibilities of DM, OM, CP, ADF, and NDF did not differ among treatments . Treatments did not affect concentration of total VFA or acetate:propionate ratio in ruminal fluid . Concentration of cholesterol in plasma was lowest when cows were fed the control diet and was greater when cows were fed prilled fatty acids than when they were fed prilled hydrogenated tallow or flaked fatty acids . The three forms of saturated fatty acids did not affect nutrient digestibilities or ruminal fermentation characteristics, but the digestibility of fatty acids in prilled hydrogenated tallow was lower than in prilled fatty acids . Digestibilities of fatty acids and other nutrient fractions and characteristics of ruminal fluid generally were similar between flaked and prilled fatty acids, despite the larger particle size of flaked fatty acids.

Appl Environ Microbiol, 1994 Mar, 60(3), 953 - 9
Rapid, sensitive PCR-based detection of mycoplasmas in simulated samples of animal sera; Dussurget O et al.; A fast and simple method to detect mycoplasmal contamination in simulated samples of animal sera by using a PCR was developed . The following five mycoplasma species that are major cell culture contaminants belonging to the class Mollicutes were investigated: Mycoplasma arginini, Acholeplasma laidlawii, Mycoplasma hyorhinis, Mycoplasma orale, and Mycoplasma fermentans . After a concentration step involving seeded sera, genus-specific primers were used to amplify a 717-bp DNA fragment within the 16S rRNA gene of mycoplasmas . In a second step, the universal PCR was followed by amplification of variable regions of the 16S rRNA gene by using species-specific primers, which allowed identification of contaminant mycoplasmas . With this method, 10 fg of purified DNA and 1 to 10 color-changing units of mycoplasmas could be detected . Since the sensitivity of the assay was increased 10-fold when the amplification products were hybridized with an internal mycoplasma-specific 32P-labelled oligonucleotide probe, a detection limit of 1 to 10 genome copies per PCR sample was obtained . This highly sensitive, specific, and simple assay may be a useful alternative to methods currently used to detect mycoplasmas in animal sera.

J Appl Bacteriol, 1994 Mar, 76(3), 282 - 7
Interactions between rumen bacterial strains during the degradation and utilization of the monosaccharides of barley straw cell-walls; Miron J et al.; Pure cultures and pair-combinations of strains representative of the rumen cellulolytic species Ruminococcus flavefaciens, Fibrobacter succinogenes and Butyrivibrio fibrisolvens were grown on cell-wall materials from barley straw . Of the pure cultures, R . flavefaciens solubilized straw most rapidly . The presence of B . fibrisolvens, which was unable to degrade straw extensively in pure culture, increased the solubilization of dry matter by R . flavefaciens and the solubilization of cell-wall carbohydrates by both R . flavefaciens and F . succinogenes . During fermentation, both R . flavefaciens and F . succinogenes released bound glucose and free and bound arabinose and xylose into solution . The accumulation of these sugars, especially arabinose and xylose, was greatly reduced in co-cultures containing B . fibrisolvens, suggesting that significant interspecies cross feeding of the products of hemicellulose hydrolysis (particularly soluble bound xylose released by F . succinogenes) occurs during straw degradation by mixed cultures containing this species.

Acta Chem Scand, 1994 Mar, 48(3), 240 - 51
Malonofungin: an antifungal aminomalonic acid from Phaeoramularia fusimaculans; Berova N et al.; In screening for antifungal metabolites, a novel compound, malonofungin, exhibiting growth inhibitory activity against Botrytis cinerea (grey mould), has been isolated from fermentations of Phaeoramularia fusimaculans CBS 616.87 . Its structure is established as (E)-(3R,4S,5S)-5-acetoxy-2-amino-2-carboxy-3,4-dihydroxy-14-oxoicos++ +-6-enoic acid, representing an addition to the rare class of naturally occurring aminomalonic acids . 1H NMR data and extensive use of CD spectroscopy have been utilized to establish the absolute stereochemistry of malonofungin . The structural and biological relationship of malonofungin to previously reported fungal metabolites is discussed.

J Gen Virol, 1994 Mar, 75 ( Pt 3), 651 - 5
Large-scale production and characterization of recombinant human immunodeficiency virus type 1 Nef; Azad AA et al.; Sequences encoding the 27K and 25K nef gene products (Nef 27 and Nef 25) were amplified by PCR from a human immunodeficiency virus type 1 infectious clone and subcloned directly into Escherichia coli, yeast and baculovirus expression vectors . The yeast- and baculovirus-derived Nef had native N termini but the expression levels were low . The expression levels of the E . coli-derived glutathione S-transferase-Nef fusion proteins were very high and a major portion was soluble . Large-scale production of E . coli-derived Nef 27 and Nef 25 was carried out by growing recombinant cells in a fermenter under fed-batch conditions followed by affinity purification on glutathione-Sepharose before and after thrombin cleavage . Large quantities of highly purified recombinant Nef proteins have been produced for functional and structural studies . Under non-reducing conditions both Nef 27 and Nef 25 existed as a mixture of monomers, dimers and small amounts of higher oligomers, but when reduced were monomeric . The highly purified Nef proteins had no G protein activities, however Nef 27 was biologically active . When electroporated into uninfected CD4+ T lymphocytes both E . coli-derived Nef 27 and yeast-derived myristylated Nef 27 down-regulated the surface expression of CD4, demonstrating that this method can be used to assess the biological activity of purified recombinant Nef.

Eur J Biochem, 1994 Mar 1, 220(2), 585 - 91
Origin of carbon atoms of biotin . 13C-NMR studies on biotin biosynthesis in Escherichia coli; Ifuku O et al.; The origin of the carbon atoms of pimeloyl-CoA, the earliest known precursor in the pathway of de novo biotin biosynthesis in Escherichia coli, was investigated by 13C-NMR spectroscopy . In fermentation of the biotin-overproducing DRK332/pXBA312 strain of Escherichia coli (a repressor mutant carrying a biotin operon fragment in the plasmid), a high dose of L-alanine (8 g/l) stimulated dethiobiotin and biotin accumulation . Although L-alanine is a known precursor of 7-keto-8-aminopelargonic acid in biotin biosynthesis, the 13C-NMR spectrum of dethiobiotin showed that the C-3 of L-{3-13C}alanine was incorporated into not only the methyl carbon (C-9) but also alternate carbons (C-2, C-4, C-6) of the side chain, and these latter positions are the same as those labeled with D-{1-13C}glucose . These data indicate that L-alanine can act as an alternative carbon source, suggesting that acetyl-CoA is a possible precursor for pimeloyl-CoA synthesis . In accordance with this hypothesis, the C-1 of sodium (1-13C)acetate and the C-2 of sodium (2-13C)acetate were incorporated into alternate carbons in the side chain of dethiobiotin, i.e., (C-1, C-3, C-5, C-7) and (C-1, C-2, C-4, C-6), respectively . These results suggested firstly that in E . coli pimeloyl-CoA is biosynthesized from L-alanine and/or acetate via acetyl-CoA, but not via pimelic acid, which has been suggested as a biotin precursor in other species, and secondly that the carboxyl group of biotin originates from carbon dioxide produced through the tricarboxylic acid cycle.

Am J Clin Nutr, 1994 Mar, 59(3 Suppl), 763S - 769S
Undigestible sugars in food products; Bornet FR; In the field of sucrose replacement, low-energy bulk ingredients must be used to lower the energy density of food . Ideally, low-energy bulk ingredients as a substitute for sucrose should have significantly less energy, possess physical and chemical properties that precisely match those of sucrose in all food applications, provide secondary health benefits (such as being noncariogenic, being useful for diabetics, and having fiber-like effects), confer no negative side effects, and be completely safe at any amount of consumption . The food industry has developed a range of low-energy bulk ingredients . Most of these are legally permitted in food applications and are undigestible sugars (eg, polyols and fructo-oligosaccharides) . Their main nutritional properties (energy value, digestive tolerance, and cariogenicity) are related to their fate in the digestive tract, especially their capacity to be used and fermented by bacteria.

Am J Clin Nutr, 1994 Mar, 59(3 Suppl), 719S - 727S
Carbohydrates and dental health; Navia JM; Carbohydrates, together with fats and proteins, provide the necessary energy needs for humans, and constitute, therefore, an integral part of a normal diet . An etiological model for caries that considers local and host factors is presented, highlighting the interaction of bacteria, saliva, minerals, and trace elements with food residues and with other intrinsic environmental and behavioral characteristics of the host . Consideration of this complex multifactorial etiology precludes the identification of any one factor as the only one to be singled out in prevention and management of oral disease . Sugar is, unquestionably, a risk factor for caries, and, therefore, its total substitution with energetic or nonenergetic sweeteners has been found useful . However, partial substitutions of fermentable sugars may have limited practical value in controlling caries prevalence . Caries preventive programs that take into consideration not one, but several etiologic factors, will be effective and beneficial to the general population.

Am J Clin Nutr, 1994 Mar, 59(3), 626 - 30
Effect of resistant starch on breath-hydrogen and methane excretion in healthy volunteers; van Munster IP et al.; Colonic fermentation of dietary carbohydrates and fiber might produce a protective effect against the development of large bowel cancer . Resistant starch, ie, starch that escapes small bowel digestion, is a candidate fermentable substrate that has been hitherto little studied . We supplemented 19 healthy volunteers with 15 g native amylomaize (Hylon-VII) three times a day, containing 28 g type II resistant starch, or with dextrins as a placebo for 7 d in a crossover design . Pre-experimentally, 11 subjects regularly produced breath methane and 8 did not . Resistant starch increased 24-h integrated excretion of breath hydrogen . The mean rise relative to placebo was 35% (P = 0.03) for all subjects and 60% for eight subjects not producing methane (P = 0.02) . The 11 methane producers showed a 93% increase in breath-methane excretion on resistant starch (P = 0.03) . Continued consumption of 28 g type II resistant starch/d is well tolerated and increases colonic fermentation in healthy volunteers.

Cancer Epidemiol Biomarkers Prev, 1994 Mar, 3(2), 149 - 53
Use of breath hydrogen and methane as markers of colonic fermentation in epidemiological studies: variability in excretion; Wilkens LR et al.; Breath hydrogen and methane are specific end products of colonic fermentation, a process which may play a protective role against colon cancer . To assess the possibility of using these markers in epidemiological studies, we characterized the intra- and intersubject variability of breath hydrogen and methane excretion over 15 consecutive days among 32 men and women of various ethnic backgrounds (16 Asians, 8 Caucasians, 8 Hawaiians) . Participants were asked to collect four end-expiratory samples each day, which we had shown previously would optimally characterize daily hydrogen excretion . There was substantial within-subject variation in breath hydrogen over the study, although breath methane levels were more constant over time . We found that about 4 days of measurement of breath hydrogen and 1 day of measurement for breath methane are required to correctly characterize individuals according to their long-term excretion of these gases . This was true for Asians and non-Asians . Although breath methane appears to be more practical to measure, it is a less sensitive marker of colonic fermentation than breath hydrogen . Whereas all subjects excreted hydrogen, only 28% of the subjects excreted methane, and methane excretor status of a few participants varied during the study . Because the breath test is noninvasive and reliable, we tested the multiple day collection protocol among colon cancer patients and controls and found it to be well accepted . We conclude that it is practical to measure breath hydrogen and methane in large epidemiological studies conducted at the individual level . The potential use for these markers is discussed.

Int J Food Microbiol, 1994 Mar, 21(4), 315 - 23
Population dynamics of natural Saccharomyces strains during wine fermentation; Querol A et al.; Using mitochondrial DNA restriction endonuclease analysis, the dynamics of the natural Saccharomyces cerevisiae strains present in spontaneous wine fermentations have been studied . We observed a sequential substitution of Sacch . cerevisiae strains along fermentation agreeing with different fermentation phases . When the restriction pattern's similarity (measured as the fraction of shared restriction fragments) was high, a clear sequential substitution of the strains was seen . However, when the similarity was low, although a sequential substitution could be also observed between secondary strains, a clearly predominant strain was present along the whole fermentation process.

Yeast, 1994 Mar, 10(3), 283 - 96
Physiological characterization of the yeast metallothionein (CUP1) promoter, and consequences of overexpressing its transcriptional activator, ACE1; Hottiger T et al.; Using the anticoagulant, hirudin, from the leech Hirudo medicinalis as a secreted reporter protein, the influence of physiological parameters on activity and regulation of the yeast (Saccharomyces cerevisiae) metallothionein (CUP1) promoter was studied . Induction of CUP1-directed hirudin expression from 2 mu-based vectors was possible at any time point during diauxic batch growth, even in cells approaching stationary phase . The highest titers of hirudin were obtained when the CUP1 promoter was activated immediately following inoculation of the cultures . If such a pseudo-constitutive fermentation strategy was adopted, the promoter was superior to an optimized variant (GAPFL) of the strong, constitutive GAPDH promoter . This superiority was primarily due to the relative independence of CUP1 promoter activity of the physiological status of host cells: whilst the maximal strength of the CUP1 and GAPFL promoters was comparable, CUP1-directed hirudin expression was high in all phases of diauxic batch growth, whereas hirudin production from the GAPFL promoter declined in post-diauxic cultures . High activity of the CUP1 promoter was observed on both a fermentable (glucose) and a non-fermentable (ethanol) carbon source . Hirudin expression could be adjusted to different levels by varying the amount of inducer (cupric sulphate) added to cultures . The copper concentrations required for maximal promoter induction had no negative effects on host growth and interfered with neither hirudin secretion nor with the biological activity of the peptide . Overexpression of the transcriptional activator, ACE1, resulted in increased levels of hirudin mRNA . Hirudin titers increased in parallel to mRNA concentrations in cultures grown in the presence of low concentrations of copper . In contrast, at high copper doses, elevated levels of the ACE1 protein resulted in inferior hirudin production . Cells overexpressing ACE1 while harbouring a CUP1-drived hirudin expression cassette showed slow growth and poor plasmid maintenance . It was tested whether this might be the result of a block in the secretory pathway; however, measurements of intracellular hirudin did not support this hypothesis . The data rather indicated that hirudin production was limited by a metabolic constraint downstream of transcription but upstream of the secretory pathway.

Nutr Rev, 1994 Mar, 52(3), 75 - 83
Diet, Helicobacter pylori infection, food preservation and gastric cancer risk: are there new roles for preventative factors?
Hwang H, Dwyer J, Russell RM.
Risks for gastric cancer in relation to diet and other environmental factors are receiving renewed attention . New developments include the emerging relationship between Helicobacter pylori infection and an increased risk for gastric cancer, and positive results of chemoprevention trials in decreasing gastric cancer risk with the use of beta-carotene and vitamin E supplements . Factors that may enhance risk include consumption of nitrites, nitrates, alcohol, and highly salted, pickled, fermented, or smoked foods . Other environmental factors which may promote cancer are H . pylori infection, inappropriate food storage, metal and cement dust exposure, and cigarette smoking . High intakes of fruits and vegetables or of antioxidants, such as beta-carotene, vitamin E, and vitamin C may decrease risk.

Genetics, 1994 Mar, 136(3), 803 - 12
Genetic variation of the repeated MAL loci in natural populations of Saccharomyces cerevisiae and Saccharomyces paradoxus; Naumov GI et al.; In Saccharomyces cerevisiae, the gene functions required to ferment the disaccharide maltose are encoded by the MAL loci . Any one of five highly sequence homologous MAL loci identified in various S . cerevisiae strains (called MAL1, 2, 3, 4 and 6) is sufficient to ferment maltose . Each is a complex of three genes encoding maltose permease, maltase and a transcription activator . This family of loci maps to telomere-linked positions on different chromosomes and most natural strains contain more than one MAL locus . A number of naturally occurring, mutant alleles of MAL1 and MAL3 have been characterized which lack one or more of the gene functions encoded by the fully functional MAL loci . Loss of these gene functions appears to have resulted from mutation and/or rearrangement within the locus . Studies to date concentrated on the standard maltose fermenting strains of S . cerevisiae available from the Berkeley Yeast Stock Center collection . In this report we extend our genetic analysis of the MAL loci to a number of maltose fermenting and nonfermenting natural strains of S . cerevisiae and Saccharomyces paradoxus . No new MAL loci were discovered but several new mutant alleles of MAL1 were identified . The evolution of this gene family is discussed.

J Antibiot (Tokyo), 1994 Mar, 47(3), 281 - 8
MLR-52, (4'-demethylamino-4',5'-dihydroxystaurosporine), a new inhibitor of protein kinase C with immunosuppressive activity; McAlpine JB et al.; In the course of screening with the mixed lymphocyte reaction, a new inhibitor of protein kinase C with immunosuppressive activity was isolated from the fermentation broth and mycelia of Streptomyces sp . AB 1869R-359 . Although certain similarities exist, this strain is morphologically and physiologically distinct from other reported producers of staurosporine-related compounds . We have found that this strain produces relatively high levels of staurosporine and the new minor compound MLR-52, which possesses the indolo{2,3-a}carbazole chromophore of staurosporine, but differs in the substitution pattern of the sugar moiety . Their structures have been elucidated by mass and NMR spectra . MLR-52 has been shown to inhibit the enzymatic activity of protein kinase C and the murine mixed lymphocyte reaction.

Phytochemistry, 1994 Mar, 35(4), 941 - 5
Biotransformation of (+)-camphor by cultured cells of Eucalyptus perriniana; Orihara Y et al.; Seven new biotransformation products were isolated from a jar fermentor culture of Eucalyptus perriniana following administration of (+)-camphor . The main product was (1S,4R,6S)-6-hydroxybornan-2-one 6-O-beta-D-glucopyranoside . The minor components were (1S,4R,6R)-6-hydroxybornan-2-one 6-O-beta-D-glucopyranoside, (1R,4S,6S)-6-hydroxybornan-2-one 6-O-beta-D-glucopyranoside, (1R,4R,5R)-5-hydroxybornan-2-one 5-O-beta-D-glucopyranoside, (1R,3R,4S)-3-hydroxybornan-2-one 3-O-beta-D-glucopyranoside, (1R,4R,7R)-8-hydroxybornan-2-one 8-O-beta-D-glucopyranoside and 2-(4-oxo-2,2,3-trimethylcyclopentyl)-ethyl-beta-D-glucopyranoside . All products were mono-glucosides and the oxygen function was introduced before glucosylation . Reduction of the ketone group of camphor was not observed.

Biotechnology (N Y), 1994 Mar, 12(3), 285 - 8
Single-step recovery of a secreted recombinant protein by expanded bed adsorption; Hansson M et al.; We have used an expanded bed adsorption procedure for efficient recovery of a recombinant fusion protein, directly from a crude fermentor broth without prior cell removal . The fusion protein was designed to have a relatively low isoelectric point (pI) to allow anionic exchange adsorption at pH 5.5 where most Escherichia coli host proteins are not adsorbed . The gene product was secreted to the culture medium of the E . coli host cells in high yields (550 mg/l) . The separation of cells and the concentration and recovery of the fusion protein could therefore be achieved by a single unit operation . The yield after the expanded bed adsorption exceeded 90 percent . Furthermore, the significant volume reduction by the expanded bed adsorption, enabled efficient and straight-forward polishing of the product by a subsequent affinity chromatography step, for removal of contaminating DNA and pyrogenic compounds to levels acceptable for regulatory authorities . An overall yield exceeding 90 percent was maintained after the affinity chromatography polishing step . The procedure outlined here is suitable for large-scale bioprocesses and allows efficient removal of cells, host proteins, contaminating DNA and endotoxins.

J Antibiot (Tokyo), 1994 Mar, 47(3), 301 - 10
FR901228, a novel antitumor bicyclic depsipeptide produced by Chromobacterium violaceum No . 968 . I . Taxonomy, fermentation, isolation, physico-chemical and biological properties, and antitumor activity; Ueda H et al.; A novel antitumor bicyclic depsipeptide, FR901228, was isolated from a broth culture of Chromobacterium violaceum No . 968 as colorless prisms and the molecular formula was determined as C24H36N4O6S2 . This antibiotic reverted the transformed morphology of a Ha-ras transformant to normal, and exhibited prominent antitumor activities against murine and human tumor cell lines both in vitro and in vivo.

J Biol Chem, 1994 Feb 25, 269(8), 6153 - 62
Fermentable and nonfermentable carbon sources sustain constitutive levels of expression of yeast triosephosphate dehydrogenase 3 gene from distinct promoter elements; Kuroda S et al.; The triosephosphate dehydrogenase 3 gene (TDH3) is a glycolytic enzyme gene and is abundantly transcribed in Saccharomyces cerevisiae . The promoter region of the TDH3 gene is known to exhibit high transcriptional activity regardless of the fermentability of the carbon source and has been widely utilized to synthesize heterologous gene products in S . cerevisiae . To clarify the mechanism of constitutive transcription by the promoter, we constructed mutant promoters and analyzed the in vivo transcriptional activity of these promoters . The majority of the transcriptional potential is contained within a DNA fragment extending from nucleotides -524 to -255 (-524/-255; relative to the translation initiation codon), which consists of three cis-acting elements: a fermentable carbon source-dependent upstream activation sequence (UAS) 1 (-524/-426), a fermentable carbon source-dependent upstream repression sequence (URS) (-426/-393), and a nonfermetable carbon source-dependent UAS2 (-305/-255) . This result indicates that the promoter involves two apparent promoter elements . One is fermentable carbon source-dependent, and another is nonfermentable carbon source-dependent . Southwestern analyses indicated that a novel 20-kDa protein is induced in yeast cells by shifting from a fermentable to nonfermentable carbon source . The protein interacts with two UAS1 13-base pair elements and one URS 13-base pair element, one of which had been previously designated GPE (general regulatory factor 1 (GRF1) binding site potentiator element) (Bitter, G . A., Chang, K . K . H., and Egan, K . M . (1991) Mol . Gen . Genet . 231, 22-32) . We therefore termed the 20-kDa protein GPEB (GRF1-binding site potentiator element-binding protein) . In addition, mutational analyses strongly suggested that UAS1, URS, and UAS2 interact with GRF1 and GPEB, GPEB, and the GCR1 (glycolysis regulation 1) gene product, respectively . We therefore concluded that constitutive transcription by the TDH3 promoter is sustained by two promoter elements and that the switch between them might be controlled by the nonfermentable carbon source-inducible GPEB.

J Biol Chem, 1994 Feb 18, 269(7), 5122 - 6
Metabolic responses to substrate futile cycling in Escherichia coli; Chao YP et al.; A cyclic pathway between phosphoenolpyruvate and oxaloacetate was created in Escherichia coli by simultaneous overexpression of phosphoenolpyruvate carboxykinase (encoded by pck) and phosphoenopyruvate carboxylase (encoded by ppc) from a multicopy plasmid under the control of the tac promoter . The simultaneous overexpression of these two enzymes stimulated oxygen and glucose consumption, reduced growth yields, and resulted in high level excretion of pyruvate and acetate . These responses were abolished when either pck or ppc was deleted from the plasmid or when both enzymes were inactivated by mutation . Therefore, the observed effects imply the existence of futile cycling . Incremental induction of futile cycling showed that stimulation of oxygen consumption was the first response, followed by the increased glucose consumption and the excretion of fermentation products . The specific growth rate of E . coli was insensitive to futile cycling per se, because the growth rate was also reduced by the overexpression of inactive enzymes at high levels, and the activity of the two enzymes did not inhibit growth further . Wild-type cells appear to be capable of compensating for the increased ATP drain due to futile cycling but cannot be as effective when a tricarboxylic acid cycle enzyme, alpha-ketoglutarate dehydrogenase, is defective.

J Biol Chem, 1994 Feb 18, 269(7), 4878 - 82
The effect of increased phosphoglucose isomerase on glucose metabolism in Saccharomyces cerevisiae; Benevolensky SV et al.; Comparison of microbial strains with normal and high content of single enzymes is coming into use for metabolic analysis and in vivo assessment of enzyme function . We present an example for phosphoglucose isomerase and glucose metabolism in the yeast Saccharomyces cerevisiae . We use cell suspensions in conditions of inhibited protein synthesis and respiration, with low assimilation, rapid and linear glucose utilization, fermentation almost quantitative, and high enough cell density for direct preparation of extracts for metabolite analysis . The mass action ratio and fitting of fructose-6-P and glucose-6-P concentrations and kinetic parameters of the enzyme are not inconsistent with near equilibrium of the reaction in the wild-type strain and small if any change in the high level strain . However, this conclusion would require that the Vmax values underestimate the activity in the cell . On the other hand, the specific activities of glucose-6-P and fructose-1,6-P2 during metabolism of {2-3H}glucose are quite high which, together with knowledge of tritium exchange and isotope effects for the reaction in vitro, would point to the reaction in the wild-type strain being far from equilibrium; the specific activities are lower in the high level strain, indicating that extra enzyme is functional . One way to reconcile the latter results would be for tritium exchange to be considerably lower in vivo than known in vitro.

FEMS Microbiol Lett, 1994 Feb 15, 116(2), 131 - 6
Induction of resistance to novobiocin in the novobiocin-producing organism Streptomyces niveus; Hoggarth JH et al.; During growth of Streptomyces niveus wild-type in the novobiocin production medium CDM the resistance of mycelia to novobiocin rises from about 25 micrograms/ml to over 200 micrograms/ml . (S . lividans, a novobiocin-sensitive strain, is resistant to approx . 10 micrograms/ml novobiocin.) The initial period of low level resistance extends from the time of inoculation of the culture until approx . 70 h when the culture is still in the growth phase . High level resistance is initiated before the start of novobiocin production and rises rapidly to a maximum level beyond the end of the growth phase . The rise in pH of the unbuffered CDM medium which occurs during S . niveus fermentation was shown not to be the cause of the change in novobiocin resistance . However, mycelia-free CDM from S . niveus cultures expressing high level novobiocin resistance was shown to contain a factor which induced high level novobiocin resistance in germinating S . niveus spores . Kinetic studies revealed that the inducer first appears in the culture medium before the switch to high level resistance begins and reaches its highest concentration before resistance reaches its maximum level.

FEBS Lett, 1994 Feb 14, 339(1-2), 1 - 6
Analysis of revertants from respiratory deficient mutants within the center N of cytochrome b in Saccharomyces cerevisiae; Coppee JY et al.; Four modified cytochrome b's carrying mononucleotide substitutions affecting center N residues were analysed . The mutant carrying a G33D change does not incorporate heme into the apocytochrome b and fails to grow on non-fermentable carbon sources . Out of 85 genetically independent revertants derived from this mutant, 82 were true back-mutants restoring the wild type sequence (D33G) . The remaining three replaced the aspartic acid by an alanine (D33A) indicating that small size residues are best tolerated at this position which is consistent with the perfect conservation of the G33 during evolution . This glycine may be of crucial importance for helix packing around the hemes . The replacement of methionine at position 221 by lysine (M221K) produced a non-functional cytochrome b {(1993) J . Biol . Chem . 268, 15626-15632} . Non-native revertants replacing the lysine 221 by glutamic acid (K221E) or glutamine (K221Q) expressed a selective resistance to antimycin and antimycin derivatives having a modified dilactone ring moiety . Cytochrome b residues in 33 and in 221 seemed to contribute to the quinone reduction (QN) site of the cytochrome bc1 complex . Possible intramolecular interactions between the N-terminal region and the loop connecting helices IV and V of cytochrome b are proposed.

J Immunol Methods, 1994 Feb 10, 168(2), 245 - 52
Use of Merocyanine 540 and Hoechst 33258 for the selective killing of contaminating mycoplasmas in cell cultures; Tarshis M et al.; Mycoplasma infection can substantially affect the biological properties of cells in vitro . We have devised a method for the selective killing of mycoplasmas, e.g., A . laidlawii, M . fermentans, M . hyorhinis and M . arginini, from experimentally infected cell cultures . This approach is based on the differential binding of the lipophilic fluorescent probe Merocyanine 540 followed by illumination with visible light . The efficiency of the procedure depends on the Merocyanine 540 concentration, the intensity of illumination, and the presence of oxygen in the medium . When A . laidlawii contaminated corneal endothelial cell cultures were treated simultaneously with Merocyanine 540 and DNA-binding fluorochrome Hoechst 33258 and then illuminated, a significant degree of eradication was observed, even after one cycle of treatment . This combined treatment is therefore recommended as an effective method of purging mycoplasmas from contaminated cultures.

J Chromatogr A, 1994 Feb 4, 660(1-2), 153 - 67
Enzyme-based biosensor as a selective detection unit in column liquid chromatography; Marko-Varga G et al.; A reagentless enzyme electrode based on co-immobilized alcohol oxidase and horseradish peroxidase was used as the working electrode in an amperometric flow-through cell connected to a column liquid chromatographic (CLC) system for the selective detection of methanol and ethanol . The enzymes were covalently immobilized in carbon paste (graphite-phenylmethylsilicone oil) in the presence of polyethylenimine . Electrodes prepared from the enzyme-modified carbon paste were optimized with respect to their sensitivity and selectivity . Different membranes were cast or electropolymerized directly on the surface of the electrode to increase the long-term stability of the biosensor . The compatibility with the reversed-phase chromatographic system was established . A PLRP-S polymer-based separation column was used with phosphate buffer as the mobile phase . The selectivity of the enzyme electrode was also determined by injecting some easily oxidizable and possibly interfering species normally present in biological samples . The enzyme electrode was also used in an on-line system, consisting of a microdialysis probe as the sampling unit, the CLC system and the biosensor detection device, for the selective following of the ethanol produced when a paper pulp industrial waste water was fermented with Saccharomyces cerevisiae.

Am J Gastroenterol, 1994 Feb, 89(2), 179 - 83
Treatment of refractory ulcerative proctosigmoiditis with butyrate enemas; Steinhart AH et al.; BACKGROUND: It is well established that the colonic mucosa is highly dependent upon the luminal presentation of nutrients . This dependence is most marked in the distal colon . The major luminal nutrients are short chain fatty acids (SCFA) that are produced as a by-product of colonic fermentation of carbohydrates . Butyrate appears to be the SCFA that is most avidly metabolized by the colonic mucosa . It has been suggested that ulcerative colitis (UC) is, at least in part, related to an energy deficiency state of the colonic mucosa which may be secondary to impaired SCFA production, uptake, or utilization . OBJECTIVE: To determine if butyrate enemas are safe and effective in refractory distal UC . METHODS: Ten patients with distal UC, refractory to all other available forms of rectal therapy and to oral sulfasalazine or mesalamine (5-ASA), were treated with nightly butyrate enemas in an open-label study . Enemas consisted of 60 ml of 80 mM sodium butyrate titrated to a pH of 7.0 . Patients were assessed clinically and endoscopically at baseline and at 3- to 6-wk intervals, and a disease activity score from 0 to 12 was determined . Response to therapy was determined by changes in the activity score . RESULTS: Six of 10 patients responded to therapy . Four of these six had complete responses . The mean disease activity score of all 10 patients fell from 8.0 +/- 2.4 (mean +/- SD) to 4.3 +/- 4.1 at the end of follow-up . Response to therapy could not be predicted based on any of the baseline characteristics analyzed . CONCLUSIONS: In this open-label study, patients with distal UC who were refractory to all previous therapy had a 40% complete response rate and an overall 60% response rate . Controlled studies of this promising therapy are indicated.

J Bacteriol, 1994 Feb, 176(3), 830 - 9
The Escherichia coli gapA gene is transcribed by the vegetative RNA polymerase holoenzyme E sigma 70 and by the heat shock RNA polymerase E sigma 32; Charpentier B et al.; Escherichia coli D-glyceraldehyde-3-phosphate dehydrogenase (GAPDH) is produced by the gapA gene and is structurally related to eukaryotic GAPDHs . These facts led to the proposal that the gapA gene originated by a horizontal transfer of genetic information . The yields and start sites of gapA mRNAs produced in various fermentation conditions and genetic contexts were analyzed by primer extension . The transcriptional regulatory region of the gapA gene was found to contain four promoter sequences, three recognized by the vegetative RNA polymerase E sigma 70 and one recognized by the heat shock RNA polymerase E sigma 32 . Transcription of gapA by E sigma 32 is activated in the logarithmic phase under conditions of starvation and of heat shock . Using a GAPDH- strain, we found that GAPDH production has a positive effect on cell growth at 43 degrees C . Thus, E . coli GAPDH displays some features of heat shock proteins . One of the gapA promoter sequences transcribed by E sigma 70 is subject to catabolic repression . Another one has growth phase-dependent efficiency . This complex area of differentially regulated promoters allows the production of large amounts of gapA transcripts in a wide variety of environmental conditions . On the basis of these data, the present view of E sigma 32 RNA polymerase function has to be enlarged, and the various hypotheses on E . coli gapA gene origin have to be reexamined.

Br J Orthod, 1994 Feb, 21(1), 23 - 6
L(+)-lactic acid production in plaque from orthodontic appliances retained with glass ionomer cement; Hallgren A et al.; The lactic acid production in suspensions of plaque collected adjacent to orthodontic brackets retained with a glass ionomer cement (GIC), or a resin-based composite was investigated using a split-mouth technique . Forty-eight-hour-old plaque was collected at 3, 8, and 28 days, and 3 months after the onset of orthodontic treatment . Acid fermentation was induced by glucose and the L(+)-lactic acid concentrations were determined enzymatically after a 30-minute incubation period . Significantly (P < 0.05) lower levels of lactic acid were found in plaque from GIC-retained brackets compared with the composite controls at the 28 days and 3 months sampling occasions, respectively . The results suggest that the use of GIC as a bonding agent in orthodontics can be beneficial for patients assessed at risk of caries development.

J Dairy Sci, 1994 Feb, 77(2), 566 - 75
Kinetics of niacin supplements in lactating dairy cows; Campbell JM et al.; The kinetics of niacin supplements in lactating dairy cows and the stability of supplements during in vitro fermentation were examined . Four multiparous Holstein cows (200 DIM) with ruminal and duodenal cannulas were fed a TMR either unsupplemented or supplemented with 12 g/d of nicotinic acid, 12 g/d of nicotinamide, or 6 g/d combination of each niacin source in a 4 x 4 Latin square design . Ruminal and duodenal concentrations of nicotinic acid increased with niacin supplementation, but DMI, yields of milk and FCM, most measures of milk composition, ruminal VFA, and plasma NEFA and BHBA concentrations were unaffected by niacin supplementation at this stage of lactation . Apparent digestibilities of most nutrients were greater when both sources of niacin were supplemented than when either source was supplemented separately . Duodenal nicotinic acid concentrations were higher for cows supplemented with nicotinamide than for cows receiving nicotinic acid, but the opposite was true for nicotinic acid concentrations in plasma . The results of both experiments indicated that nicotinamide was converted rapidly to nicotinic acid by microorganisms in the reticulorumen . Supplementation with either nicotinic acid or nicotinamide effectively can increase the amount of nicotinic acid available to the cow; however, some source effects remain to be explained.

J Dairy Sci, 1994 Feb, 77(2), 552 - 9
Forestomach and whole tract digestion in lactating dairy cows fed canola meal treated with variable levels of acetic acid; Robinson PH et al.; Five Holstein cows in midlactation were fed four isonitrogenous (mean 2.76% N) mixed diets containing untreated canola meal or replaced with canola meal treated with 0, 33, 67, or 100% of acetic acid in a 12-wk 4 x 4 Latin square experiment . Diets were 50% barely-based concentrate, 12% canola meal, 30% whole crop oat silage, and 8% alfalfa silage (DM basis) . Fore-stomach and whole tract apparent digestibilities of DM, OM, and its components, including fiber and CP, did not differ as proportions of treated canola meal increased . Rumen pool sizes of OM, NDF, and bacterial OM, as well as total NAN and bacterial N, were not influenced by treatment, although bacterial N pool size tended to decline as treated canola meal replaced untreated . This result was consistent with a trend for reduced flow of bacterial N at the duodenum . Duodenal flow of AA protein, and its profile, was not influenced by treatment . Results suggest that low level replacement of untreated canola meal with canola meal treated with acetic acid stimulated microbial growth by providing more sustained delivery of slowly degraded true protein . However, at higher substitution, the rumen microbial pool was reduced progressively, perhaps because of a shortage of readily fermentable N . This hypothesis, although not consistent with all data, seems to be the most plausible explanation for all observations, although it is clear that differences in both digestion and duodenal flow, particularly for protein, attributable to replacement of untreated canola meal by that treated with acetic acid were moderate.

J Dairy Sci, 1994 Feb, 77(2), 501 - 12
Effects of enzyme-inoculant systems on preservation and nutritive value of haycrop and corn silages; Chen J et al.; Third-crop mixed grass-legume forage and corn were ensiled in 70-tonne bunker silos to evaluate the effects of a commercial carbohydrase enzyme-inoculant mixture (220 ml/tonne) and an experimental enzyme-inoculant mixture (264 ml/tonne) on silage fermentation and composition, ruminal degradation, and milk production . Twelve Jersey and 24 Holstein early lactation cows were fed one of four TMR at 32.5:32.5:35.0 haycrop silage:corn silage:concentrate (DM basis) containing a combination of treated and untreated silages from d 2 to 100 of lactation . Bunker silages were incubated twice in situ in fistulated cows in each dietary treatment to determine rates of DM and NDF degradation . Treatment of haycrop silage significantly reduced silage pH and acetic acid concentration and increased titratable acidity, lactic acid concentration, lactate: acetate ratio, and DM and NDF disappearances after 24 h of ruminal incubation . Treated haycrop silage increased DMI:BW ratio and daily production of milk, milk protein, and SNF of early lactation cows . Application of the experimental mixture to corn silage did not change silage fermentation or composition, except that the concentration of NH3 was reduced . Enxyme-treated corn silage did not improve DMI and slightly reduced daily milk production in early lactation cows.

J Dairy Sci, 1994 Feb, 77(2), 492 - 500
Changes in total and individual proteins during drying, ensiling, and ruminal fermentation of forages; Messman MA et al.; Effects of wilting, drying, and ensiling on concentrations of proteins in alfalfa, crown vetch, perennial ryegrass, orchardgrass, and tall fescue were studied using SDS-PAGE . Seven to nine proteins were identified in the samples . Wilting forages for 24 h on a laboratory bench had little effect on the relative amounts of proteins . Drying forage (on a laboratory bench) for 5 d resulted in a 25 to 30% loss in electrophoretically identified proteins . A 45-kDa protein was more susceptible to hydrolysis during drying than were most other proteins . After ensiling, < 10% of the proteins in fresh alfalfa and fescue remained, but crown vetch silage contained 46% of its original proteins . A 54-kDa protein was extremely susceptible to hydrolysis during ensiling, but a 30-kDa protein was relatively resistant . Fresh forage and hay samples were incubated in vitro for 5 h to determine degradation of proteins . In general, the 54-kDa protein was most susceptible, and the 30-kDa protein was least susceptible, to ruminal hydrolysis . Certain proteins in hay were more degradable than those in fresh forage . Among fresh forages, alfalfa and fescue contained the lowest concentrations of undegradable proteins . Differences among forage species were considerably less for hay samples.

Protein Expr Purif, 1994 Feb, 5(1), 70 - 5
Rapid purification of recombinant human tumor necrosis factor beta; Loh KC et al.; A rapid and improved method for the purification of recombinant human tumor necrosis factor beta (rhTNF-beta) from Escherichia coli HB 101 cells has been developed . The method utilized sequential steps of polyethylenimine (PEI) and ammonium sulfate precipitation to remove most of the extraneous proteins and nucleic acids from the cell extracts . The final step of purification consisted of DEAE-Sepharose chromatography at pH 7.5 in which rhTNF-beta was eluted with starting buffer . This procedure, when compared to the earlier methods of purification, is highly efficient since we could increase the overall yield of rhTNF-beta and reduce the purification time considerably . The final yield that we obtained from 1 liter of fermentation broth (containing approximately 80 g of wet cells) was 40-50 mg.

Protein Expr Purif, 1994 Feb, 5(1), 65 - 9
Improved expression and evaluation of polyethyleneimine precipitation in isolation of recombinant cysteine proteinase inhibitor stefin B; Jerala R et al.; Synthetic gene coding for human cysteine proteinase inhibitor stefin B was expressed in Escherichia coli by the use of pKP1500 plasmid-containing tac promotor and temperature-sensitive origin of replication, ensuring high plasmid copy number . Several parameters were varied in order to maximize the yield of inhibitory active protein: distance between RBS and initiator codon, temperature of fermentation, and conditions of fermentation . Production of stefin B was markedly improved by setting the RBS to ATG codon distance to 10 nt and with fermentation conditions that increased yield of biomass . The isolation procedure was modified by including precipitation with polyethyleneimine that removed contaminants such as nucleic acids and most bacterial (predominantly acidic) proteins . Precipitation itself produced more than 80% pure recombinant inhibitor, which was purified to homogeneity by a single chromatographic step . Isolated protein had the same inhibitory properties as authentic inhibitor.

J Anim Sci, 1994 Feb, 72(2), 509 - 14
Effects of substituting feather meal for soybean meal on ruminal fiber fermentation and lamb and wool growth; Thomas VM et al.; Our objective was to evaluate the effects of substituting feather meal (FM) for soybean meal (SBM) on ruminal fiber fermentation, lamb gain, blood metabolite profiles, and wool growth . A SBM supplement was formulated, and FM replaced either 33% (33FM), 66% (66FM), or 100% (FMS) of the SBM protein . Four ruminally cannulated wethers were used in a 4 x 4 Latin square design to study in situ ruminal digestion . Wethers were limit-fed barley straw and fed the supplements once daily . Ruminal NH3 N concentrations reflected a sampling time x protein source interaction (P < .01) . Within sampling times, ruminal NH3 N concentrations decreased linearly (P < .05) as FM replaced soybean meal . Cubic (0 h; P < .10) and quadratic (24 h; P < .05) responses also were noted for ruminal NH3 N concentration . Substitution of FM for SBM had no effect (P > .10) on rate and extent of straw NDF disappearance . A 56-d feeding trial was conducted using 28 wether lambs (n = 7 per treatment; initial BW 32.3 kg) . Wethers were individually fed chopped barley straw and one of the four supplements described previously . Linear increases (P < .05) in BW gain and serum total protein concentration were observed as FM replaced SBM . Wool fiber diameter and sulfur content did not differ (P > .10) among treatments . These data suggest that FM can be substituted for SBM in protein supplements fed to sheep consuming low-quality roughages at a maintenance level of ME intake.

J Anim Sci, 1994 Feb, 72(2), 478 - 86
Steers grazing intermediate wheatgrass at various stages of maturity: effects on nutrient quality, forage intake, digesta kinetics, ruminal fermentation, and serum hormones and metabolites; Park KK et al.; Six ruminally cannulated Holstein steers (average BW of 495 +/- 5 kg) grazed a 32-ha, nonirrigated, intermediate wheatgrass (Thinopyrum intermedium Host) pasture from April 10 through December 7 . Sample collections were conducted in May, June, September, and November 1989 . Total masticate N decreased (P < .05) and bound N increased (P < .05) with advancing forage maturity . Masticate in vitro OM disappearance was lower (P < .05) in November (40.5%) than in May (62.0%) . Organic matter intake (grams/kilogram of BW) decreased (P < .05) at each sampling date (May = 35.7, June = 26.8, September = 20.0, November = 14.9) . Correspondingly, particulate passage rate decreased and gastrointestinal mean retention time increased (P < .05) with advancing forage maturity . Extent and rate of NDF digestion were greater (P < .05) during May and June than during September and November . Ruminal NH3 N and total VFA concentrations were greater (P < .05) during May and June than during September and November . Advancing forage maturity did not alter (P > .10) serum growth hormone concentrations; however, nonesterified fatty acid concentrations were greater (P < .05) during September and November than during May and June . Serum insulin-like growth factor I decreased (P < .05) with advancing forage maturity . Seasonal changes in forage intake and ruminal fermentation suggest that animal performance might be increased if supplemental energy is provided early in the growing season of intermediate wheatgrass; however, supplemental protein would likely be needed as wheatgrass matures.

Plant Foods Hum Nutr, 1994 Feb, 45(2), 113 - 7
Influence of grain quality, heat, and processing time on the reduction of aflatoxin B1 levels in 'tuwo' and 'ogi': two cereal-based products; Adegoke GO et al.; During the production of 'tuwo' from laboratory-contaminated corn (AFB1:150 mcg/kg) and sorghum (AFB1:87.5 mcg/kg) grains, reductions in the aflatoxin-B1 levels of pastes boiled for 30 min and 60 min were found to be 68.0% and 80.8%, respectively . In the preparation of 'ogi' from contaminated corn and sorghum grains, reductions of about 72.5% and 71.4%, respectively, were obtained after fermentation at ambient conditions . Reconstitution of 'ogi' paste into a porridge (akamu) considerably reduced the AFB level.

J Clin Psychopharmacol, 1994 Feb, 14(1), 5 - 14
Hypertensive episode associated with phenelzine and tap beer--a reanalysis of the role of pressor amines in beer; Tailor SA et al.; A case report of a hypertensive crisis resulting from the ingestion of tap beer in a patient on an irreversible monamine oxidase inhibitor (MAOI; phenelzine) stimulated the investigation of different kinds of beer for tyramine concentration . The objective was to determine the tyramine concentration in tap and bottled beers . A total of 98 beer samples (79 different brands of beer) were analyzed by high-performance liquid chromatography for tyramine . Of these 98 beers, 49 were bottled or canned beers and 49 were beers on tap . All of the bottled beers analyzed had safe tyramine concentrations (< or = 10 mg/liter; range, 0 to 3.16 mg/liter) and, thus, do not require restriction in patients receiving MAOIs . Therefore, the consumption of canned or bottled beer, including dealcoholized beer, in moderation (fewer than four bottles or cans; 1.5 liters within a 4-hour period) appears to be safe and does not require restriction in patients receiving MAOIs . Only 4 of 98 beer samples studied were found to have a dangerous (> 10 mg/liter) tyramine concentration, one of which was the index beer . The tyramine concentration in these four beers ranged from 26.34 to 112.91 mg/liter . All four of these beers were tap beers produced by bottom fermentation (lagers) and brewed by a secondary fermentation process . Although we did not find any visible bacterial growth in the tap beers with high tyramine content, this finding does not preclude the possibility that bacterial contamination, bacterial growth, production of tyramine, and eventually bacterial death occurred at some earlier time . Therefore, to err on the side of caution, it is recommended that patients on irreversible MAOIs avoid beers on tap.

J Antibiot (Tokyo), 1994 Feb, 47(2), 163 - 7
Gypsetin, a new inhibitor of acyl-CoA:cholesterol acyltransferase produced by Nannizzia gypsea var . incurvata IFO 9228 . I . Fermentation, isolation, physico-chemical properties and biological activity; Shinohara C et al.; A novel inhibitor of acyl-CoA:cholesterol acyltransferase (ACAT), designated gypsetin, was isolated from the cultured broth of Nannizzia gypsea var . incurvata IFO 9228 by solvent extraction, silica gel chromatography and crystallization . Gypsetin inhibited rat liver microsomal ACAT activity competitively with respect to the substrate oleoyl-CoA with an apparent Ki value of 5.5 microM . In cultured macrophage J774 cells incubated with oxidized low density lipoprotein, gypsetin inhibited cholesteryl ester formation from {14C}oleate by 50% at a concentration of 0.65 microM without affecting cell surface binding, uptake and degradation of the lipoprotein.

J Antibiot (Tokyo), 1994 Feb, 47(2), 148 - 53
Pyripyropenes, novel inhibitors of acyl-CoA:cholesterol acyltransferase produced by Aspergillus fumigatus . I . Production, isolation, and biological properties; Tomoda H et al.; Aspergillus fumigatus FO-1289, a soil isolate, was found to produce a series of novel inhibitors of acyl-CoA:cholesterol acyltransferase (ACAT) . Four active compounds, named pyripyropenes A, B, C and D, were isolated from the fermentation broth of the producing strain by solvent extraction, silica gel column chromatography, ODS column chromatography and preparative HPLC . Pyripyropenes A, B, C and D show very potent ACAT inhibitory activity in an enzyme assay system using rat liver microsomes with IC50 values of 58, 117, 53 and 268 nM, respectively.

J Antibiot (Tokyo), 1994 Feb, 47(2), 136 - 42
3-Alkanoyl-5-hydroxymethyl tetronic acid homologues and resistomycin: new inhibitors of HIV-1 protease . I . Fermentation, isolation and biological activity; Roggo BE et al.; In the course of a screening program for HIV-1 protease inhibiting activity, six new homologues of 3-alkanoyl-5-hydroxymethyl tetronic acids (1 approximately 6) and the known natural product resistomycin (7) were isolated from cultures of the Actinomycete strain DSM 7357 . The substituted tetronic acids belong to a recently described structural class of secondary metabolites . The HIV-1 activity of resistomycin (7) has not been reported before.

J Antibiot (Tokyo), 1994 Feb, 47(2), 129 - 35
A new topoisomerase II inhibitor, BE-22179, produced by a streptomycete . I . Producing strain, fermentation, isolation and biological activity; Okada H et al.; A new topoisomerase II inhibitor, designated BE-22179, was isolated from the culture broth of Streptomyces sp . A22179, which resembles "Streptomyces gangtokensis" . The inhibitor was extracted from the mycelial cake of the culture broth with organic solvent and successively purified by silica gel chromatography . BE-22179 inhibited topoisomerase II strongly but not topoisomerase I and showed potent antitumor activity against various tumor cell lines both in vitro and in vivo.

Br J Nutr, 1994 Feb, 71(2), 169 - 80
Intestinal nitrogen and electrolyte movements following fermented milk ingestion in man; Mahe S et al.; The present study focuses on the digestion and absorption of milk and fermented milk (FM) reflected by gastro-ileal N and electrolyte movements in six healthy volunteers . The N and electrolyte content of the intestinal effluents were analysed both at the beginning of the jejunum and in the distal ileum . The gastric half-emptying time of the liquid phase was significantly (P < 0.05) shorter for milk (35 (SE 2) min) than for FM (60 (SE 2) min) . The N balance showed that 58 and 50% of ingested proteins, milk and FM respectively were absorbed between the stomach and the proximal jejunum and that 91 and 90% respectively were absorbed between the stomach and the terminal ileum in 240 min . Evaluation of mineral absorption indicated that 44 and 67% of Ca was absorbed in the duodenum after milk and FM ingestion respectively, and 41 and 11% of Ca disappeared between the jejunum and the ileum respectively . With regards to N and Ca intestinal availability, the present study confirms that FM products represent an interesting source of N as well as minerals for man . This confers on FM a beneficial effect compared with milk especially for lactase (EC 3.2.1.108)-deficient subjects and children with persistent diarrhoea.

Appl Environ Microbiol, 1994 Feb, 60(2), 562 - 8
Purification and characterization of NADP-specific alcohol dehydrogenase and glutamate dehydrogenase from the hyperthermophilic archaeon Thermococcus litoralis; Ma K et al.; Thermococcus litoralis is a strictly anaerobic archaeon that grows at temperatures up to 98 degrees C by fermenting peptides . Little is known about the primary metabolic pathways of this organism and, in particular, the role of enzymes that are dependent on thermolabile nicotinamide nucleotides . In this paper we show that the cytoplasmic fraction of cell extracts contained NADP-specific glutamate dehydrogenase (GDH) and NADP-specific alcohol dehydrogenase (ADH) activities, neither of which utilized NAD as a cofactor . The GDH is composed of identical subunits having an M(r) of 45,000 and had an optimal pH and optimal temperature for glutamate oxidation of 8.0 and > 95 degrees C, respectively . Potassium phosphate (60 mM), KCl (300 mM), and NaCl (300 mM) each stimulated the rate of glutamate oxidation activity between two- and threefold . For glutamate oxidation the apparent Km values at 80 degrees C for glutamate and NADP were 0.22 and 0.029 mM, respectively, and for 2-ketoglutarate reduction the apparent Km values for 2-ketoglutarate, NADPH, and NH4+ were 0.16, 0.14, and 0.63 mM, respectively . This enzyme is the first NADP-specific GDH purified form a hyperthermophilic organism . T . litoralis ADH is a tetrameric protein composed of identical subunits having an M(r) of 48,000; the optimal pH and optimal temperature for ethanol oxidation were 8.8 and 80 degrees C, respectively . In contrast to GDH activity, potassium phosphate (60 mM), KCl (0.1 M), and NaCl (0.3 M) inhibited ADH activity, whereas (NH4)2SO4 (0.1 M) had a slight stimulating effect . This enzyme exhibited broad substrate specificity for primary alcohols, but secondary alcohols were not oxidized.(ABSTRACT TRUNCATED AT 250 WORDS)

FEMS Microbiol Lett, 1994 Feb 1, 116(1), 101 - 6
Membrane-associated hemolysin activities in mycoplasmas; Minion FC et al.; Mycoplasmas are cell wall-less organisms that require membrane precursors for growth . Activities involved in the acquisition of these materials have been hypothesized as mycoplasmal virulence factors because of the effects these activities might have on host cells . Twenty-nine species or strains of mycoplasmas were examined for membrane-associated hemolysis activity similar to that previously identified in Mycoplasma pulmonis . Membrane-associated hemolytic activity was found in most mycoplasma species, but the amount of activity varied between and within the species . All of the arginine-utilizing mycoplasmal species, one M . pulmonis strain, one Acholeplasma species, and the intracellular human pathogens M . penetrans and M . fermentans ssp . incognitus were devoid of activity . The wide distribution of the membrane-associated hemolysis activity suggests that it may be important to the survival of the organism.

J Med Microbiol, 1994 Feb, 40(2), 90 - 4
Presence of eaeA sequences in pathogenic and nonpathogenic Escherichia coli strains isolated from weaned rabbits; Leroy SM et al.; Seventy-one Escherichia coli strains isolated from diarrhoeic weaned rabbits from different areas of France were tested for the presence of DNA sequences specific for the EPEC, EHEC, DAEC and EAggEC strains and 16 of them were tested for pathogenicity in animal experiments . High pathogenicity was observed only with strains unable to ferment rhamnose . DNA from all 55 rhamnose-negative O103, O26 and rough strains hybridised with the eaeA probe . Similar hybridisation was obtained with six non-pathogenic rhamnose-positive strains belonging to serogroups O128 and O132 . No hybridisation was observed with the other probes . This is the first report of the presence of eaeA sequences in genomic DNA of non-pathogenic strains.

Curr Genet, 1994 Feb, 25(2), 89 - 94
Identification of extragenic suppressors of the cif1 mutation in Saccharomyces cerevisiae; Blazquez MA et al.; The cif1 mutation of Saccharomyces cerevisiae causes inability to grow on glucose and related fermentable carbon sources . We have isolated two different suppressor mutations that allow growth on glucose of yeasts carrying the cif1 mutation . One of them, sci1-1, is recessive and caused inability to grow on non-fermentable carbon sources and to de-repress fructose-1,6-bisphosphatase . The other suppressor mutation, SCI2-1, is dominant and diminished the capacity to phosphorylate glucose or fructose . The SCI2-1 mutation decreased sporulation efficiency by 70% in heterozygosis and by more than 90% in homozygosis . In a CIF1 background, cells carrying the mutation SCI2-1 accumulated trehalose during the logarithmic phase of growth and hyperaccumulated it during the stationary phase . Genetic tests showed that SCI2 was either allelic, or else closely linked, to HXK2 . The concentrations of the glycolytic metabolites measured during growth on glucose in cells carrying the cif1 mutation and any of the suppressor mutations were similar to those of a wild-type . Both types of suppressor mutations restored the transient cAMP response to glucose to cif1 mutants.

Appl Biochem Biotechnol, 1994 Feb, 44(2), 161 - 85
Cloning of a new allelic variant of a Saccharomyces diastaticus glucoamylase gene and its introduction into industrial yeasts; Kim K et al.; A new allelic variant of the STA2 gene, designated as STA2K, coding for a secreted glucoamylase, was cloned . Differences were revealed both in the structural gene and in the promoter region, as compared to other STA genes . The most peculiar structural features of STA2K are 1 . a 1.1-kb natural deletion in its promoter located 189 nucleotides upstream of the translation start codon; and 2 . an Asn-->Asp single amino acid change within the putative active site of the encoded glucoamylase . Neither the presence of glucose in the medium nor the host cell's mating type constellation affected the expression level of STA2K in S . cerevisiae . Self-replicating yeast plasmids containing STA2K were constructed and used to transform a laboratory yeast strain and various brewing strains . Pilot brewing tests with glucoamylase-secreting transformants of a brewing strain produced superattenuated beers at accelerated fermentation rates.

Antibiot Khimioter, 1994 Feb-Mar, 39(2-3), 3 - 8
{The development of a technology for lincomycin biosynthesis with batch-type feeding of the substrates during the process}; Semenova LE et al.; It was shown possible to improve the process of lincomycin production by using batch-type feeding of the carbohydrate substrates during the biosynthesis . The optimal composition of the fermentation medium with lower concentrations of the carbohydrates was developed and batch-type feeding of the substrates was applied . The conditions of the substrate feeding were developed under laboratory conditions . Solutions of glucose or sugar supplemented with potassium sulfate were used for the feeding . The antibiotic yield under the optimal conditions of the substrate feeding and the process control was higher than that under the conditions of the batch fermentation by 23-24 per cent.

Curr Opin Biotechnol, 1994 Feb, 5(2), 192 - 5
Integrated fermentation and recovery processes; Daugulis AJ; The application of integrated fermentation and product recovery continues to be improved for products such as ethanol, acetone and butanol . An extractive fermentation process for ethanol has now been scaled up and is approaching commercialization . Integrated fermentation process design is expanding into higher value materials, such as amino acids, plant cell products and antibodies . The general concept of selective partitioning of molecules between an aqueous and second (organic) phase has also been successfully applied to controlled substrate addition.

Curr Opin Biotechnol, 1994 Feb, 5(2), 187 - 91
Fermentation monitoring and process control; Scheper TH et al.; During the past year, several papers describing the potential of new sensor devices for application in real bioprocesses have been published . Biosensors, optical sensors, and immunosensors are all gaining in importance . At present, the development of correct/adequate interfacing of biosensors to bioprocesses is the major limitation on progress . On the basis of new analytical data, a more precise modeling and control of fermentations can now be performed . Recent research efforts attest to the increasing importance of this area in biotechnology.

Curr Opin Biotechnol, 1994 Feb, 5(2), 180 - 6
Developments in high cell density and high productivity microbial fermentation; Kleman GL et al.; In the past year, new approaches to control high cell density fermentations, molecular strategies coupled with fermentation technology, and updated traditional strategies have been used to overproduce important biological products . The most significant advances include new implementation of control strategies for feeding high cell density fermentations as well as the continued development of alternative Gram-positive bacterial expression systems.

Bioseparation, 1994 Feb, 4(1), 63 - 70
Operational properties of an inverted matrix cellulose CM ion-exchanger; Ming F et al.; Productive CM is a recently available carboxymethyl ion-exchanger based on cellulose supplied by BPS Separation . It is supplied in an 'inverted matrix' form as a coherent structure with large voids and about 90% free volume . This paper reports mainly on the physical properties and robustness under normal use conditions using lysozyme as a model protein . The structure is shown by electron microscopy to be formed of fibrous or sheet material around macropores of around 100 microns in diameter . The material around the macropores is itself porous down to the smallest pores visible at perhaps 50 nm . The capacity under static and dynamic conditions was measured and found in both cases to be only slightly dependent on applied flow velocities up to 8 m h-1 . The high porosity allowed cider fermentation broth and diluted egg white to be applied directly to a column without blockage and at a moderate pressure drop yet with a high superficial velocity . Compression of the bed at high flow rates did not occur at free space velocities up to 17 m h-1 with water and slightly lower with other fluids . The adsorption isotherm was determined and found to follow a Langmuir form . It proved to be totally stable to immersion in 1 M NaOH and 1 M NaCl without any measurable volume changes . Many of the properties were compared with those of other ion-exchange resins and found to be equivalent in capacity but superior in terms of stability, sustainable flow rates and dynamic capacity . It is concluded that the stability, performance under high flow rates and good capacity make it eminently suitable for use in large scale applications.

Appl Microbiol Biotechnol, 1994 Feb, 40(6), 888 - 91
Oscillatory penicillin formation in carbon-limited batch fermentations of Penicillium chrysogenum; Siegmund D; Circadian oscillations of penicillin productivity with a period of 22 +/- 2 h have been observed in carbon-limited batch fermentations of Penicillium chrysogenum . The specific penicillin production rate oscillated with an amplitude of 20 to 100% of its mean value, depending on the growth rate of the active (respiring and producting) biomass . In spite of this, the penicillin concentration increased almost linearly if the optimum growth rate of the active biomass for maximum penicillin productivity was maintained using microprocessor control . This apparently inconsistent behaviour of the fungus is discussed on the basis of chaos theory.

Appl Microbiol Biotechnol, 1994 Feb, 40(6), 773 - 9
Enhancement of cephamycin C production using soybean oil as the sole carbon source; Park YS et al.; Vegetable oils were investigated to evaluate their potential to act as the sole carbon source for production of cephamycin C in shake and jar-fermentor cultures . Soybean oil was the best carbon source for cephamycin C production . Bioautography and HPLC analyses showed that cephamycin C was exclusively produced even when soybean oil was used as the sole carbon source . The optimal pH and initial concentration of soybean oil was 7.5 and 7 g/l, respectively . Both pH and the pH-control agent affected cephamycin C production, and among phosphoric acid, acetic acid and sulfuric acid, phosphoric acid was associated with the best production . Soybean oil was slowly consumed after the soluble nitrogen source was consumed . When the initial soybean oil concentration was 7 g/l, cephamycin C production was maximal, 2.0 g/l, which was twice as high as that from starch . The product yield from soybean oil was 4.7 times higher than that from starch . These results show that vegetable oils, which are cheaper than other carbon sources, could be used as the sole carbon source in the production of antibiotics.

J Chem Technol Biotechnol, 1994 Feb, 59(2), 157 - 63
Physicochemical factors affecting the formation of the biological response modifier scleroglucan; Taurhesia S et al.; The use of phosphate as the limiting nutrient for scleroglucan formation by Sclerotium glucanicum led to stimulation of glucan formation . Final exopolysaccharide concentrations achieved in phosphate-limited (18.9 kg m-3) cultures were much higher than in the usual nitrogen-limited fermentations (11.4 kg m-3) . The mechanism by which phosphate limitation engendered glucan formation may be largely non-specific, involving a generalised diversion of the carbon source away from biomass formation and towards glucan synthesis . The effect of stirrer speed was examined in a fermenter fitted with a 6-bladed Rushton turbine impeller of 0.5 vessel diameter . It was noted that biomass and scleroglucan formation showed different optima . This may have been due to the markedly different oxygen requirements of the two processes.

Biotechnology (N Y), 1994 Feb, 12(2), 185 - 9
High yield production and purification of recombinant staphylokinase for thrombolytic therapy; Schlott B et al.; Recombinant plasmids were constructed in which the signal sequence of the sak42D and the sakSTAR staphylokinase genes were replaced by an ATG start codon and which express staphylokinase under the control of a tac promoter and two Shine-Dalgarno sequences in tandem . Induction of transfected E . coli TGl cells in a bacterial fermentor produced intracellular staphylokinase representing 10 to 15% of total cell protein . Gram quantities of highly purified recombinant staphylokinase were obtained from cytosol fractions by chromatography, at room temperature, on SP-Sepharose and on phenyl-Sepharose columns, with yields of 50 to 70 percent . The material, at a dose of 4 mg/kg, did not produce acute reactions or affect body weight in mice . Intravenous administration of 10 mg SakSTAR over 30 minutes in five patients with acute myocardial infarction induced complete coronary artery recanalization, without associated fibrinogen degradation . However, neutralizing antibodies appeared in the plasma of all patients within 12 to 20 days . Thus, the present expression and purification method for recombinant staphylokinase yields large amounts of highly purified mature protein (approximately 200 mg per liter fermentation broth) suitable for a more detailed clinical investigation of its potential as a thrombolytic agent.

Hindustan Antibiot Bull, 1994 Feb-May, 36(1-2), 30 - 3
Regulatory enzymes for the screening of streptomycin producing mutant strains of Streptomyces griseus; Maladkar NK; Intermediary enzymes of streptomycin biosynthesis-arginine amidinotransferase and alkaline phosphatase were located at the early fermentation stages . Their relationship with streptomycin production by Streptomyces griseus strains GX-19 and MR-20 was determined and the use of this relationship was made for the screening of streptomycin producing mutant strains.

Hindustan Antibiot Bull, 1994 Feb-May, 36(1-2), 1 - 5
Effect of dissolved oxygen levels on biosynthesis of aureofungin by Streptoverticillium cinnamoneum var . terricola; Patankar PV et al.; Biosynthesis of aureofungin by Streptoverticillium cinnamoneum var, terricola was found to be an oxygen dependent reaction . An accelerated rate of aureofungin production, along with a better yield coefficient were obtained under conditions of enhanced aeration during fermentation . A higher oxygen transfer rate was found to stimulate aureofungin A, and suppresses aureofungin B formation.

J Biol Chem, 1994 Jan 14, 269(2), 1270 - 5
Deletion of QCR6, the gene encoding subunit six of the mitochondrial cytochrome bc1 complex, blocks maturation of cytochrome c1, and causes temperature-sensitive petite growth in Saccharomyces cerevisiae; Yang M et al.; It was previously reported that disruption or deletion of QCR6, the nuclear gene encoding subunit 6 of the cytochrome bc1 complex, does not impair growth of yeast on non-fermentable carbon sources (Schoppink, P . J., Hemrika, W., Reyne, J . M., Grivell, L.A., and Berden, J . A . (1988) Eur . J . Biochem . 113, 115-122; Crivellone, M . D., Wu, M . M., and Tzagoloff, A . (1988) J . Biol . Chem . 262, 14323-14333; Schmitt, M . E., and Trumpower, B . L . (1990) J . Biol . Chem . 265, 17005-17011) . We have discovered that deletion of QCR6 results in a temperature-sensitive petite phenotype, manifested at 37 degrees C, and that this phenotype can be masked by spontaneously arising suppressor mutations . Mitochondrial membranes from the deletion strain grown at 37 degrees C lack ubiquinol-cytochrome c reductase activity, and optical spectra reveal an extensive decrease in cytochrome b absorption, but little or no decrease in cytochrome c1 absorption . Immunoblots of mitochondrial membrane proteins from the deletion strain indicate that processing of cytochrome c1 from intermediate to mature size is blocked coincident with the loss of subunit 6 . This is the first example where mutation of a subunit within the bc1 complex blocks maturation of cytochrome c1.

J Chromatogr A, 1994 Jan 14, 658(2), 459 - 63
Removal of DNA contaminants from therapeutic protein preparations; Ng P et al.; Mammalian cell culture-derived biotechnical products for therapeutic use have risks associated with cell substrate DNA . Regulatory authorities in the USA and Europe have set stringent limits for this contaminant, requiring orders of magnitude reduction from fermenter harvests to purified products . This paper addresses the relevant unit processes (e.g., cell separation, affinity chromatography and ion-exchange chromatography) utilized for purification of mammalian cell culture-derived products as they pertain to removal of DNA contaminants.

Carbohydr Res, 1994 Jan 3, 251, 303 - 13
Structure and physical properties of the extracellular polysaccharide PS-P4 produced by Sphingomonas paucimobilis P4 (DSM 6418); Lobas D et al.; A new strain, Sphingomonas paucimobilis P4 (DSM 6418), was found during a screening programme for exopolysaccharide-producing bacteria . The highly viscous fermentation broth yields a polysaccharide (up to 10 kg/m3), named PS-P4, and shows thixotropic flow behaviour . In the presence of phosphate ions, PS-P4 forms aqueous gels after heating and cooling at alkaline pH . After isolation and purification of the exopolysaccharide, structural analysis by 1D and 2D 1H NMR spectroscopy and mass spectrometry was performed . The deacylated exopolysaccharide has the following repeating trisaccharide structure:-->4)-beta-D-Glcp-(1-->4)-alpha-L-Rhap-(1-->3)-beta-D- Glcp(1-->Additionally, the presence of ester-bound acetic acid, D-glyceric acid, and (R)-3-hydroxybutyric acid in the native polysaccharide was demonstrated.

J Immunol Methods, 1994 Jan 3, 167(1-2), 173 - 82
Assay and purification of Fv fragments in fermenter cultures: design and evaluation of generic binding reagents; Berry MJ et al.; Fv fragments whose genes have been cloned using common PCR primers carry identical peptide motifs at their termini . We have raised antibodies against the C-terminal motif of the VH chain GQGTTVTVSS and evaluated their utility as reagents for the assay and purification of Fvs in the fermenter culture . Three different Fvs were included in the investigation . We found that the motif was exposed and available for capture when Fv fragments were blotted onto nitrocellulose paper or adsorbed directly onto microtiter plates . In contrast, the motif was either partially or totally obscured when the Fv was complexed with immobilised antigen or when free in solution . This reactivity profile enabled us to develop a general-purpose assay for Fv protein, but not a general-purpose assay for monitoring active Fv . The apparent inaccessibility of the C-terminus of VH conflicts with currently held views on the three-dimensional structure of these molecules.

Folia Microbiol (Praha), 1994, 39(6), 489 - 92
An expert system applied to the physiological analysis of early stage of beer fermentation; Vassileva S et al.; A fuzzy expert system was applied to the knowledge analysis of yeast physiology in the early stage of beer fermentation, when the wort was aerated . We used ergosterol and glycogen concentration in the wort as a suitable marker of physiological state of the cell population . The amount of both compounds influences the rate of fermentation, cell growth and the final taste of beer . The concentrations of ergosterol and glycogen including the number of cells can not be measured immediately during the relatively short aeration period, and incomplete experimental data are therefore found in laboratory logbooks . We therefore suggested that the fuzzy relation between the directly measurable dissolved oxygen concentration and the rate of ergosterol or glycogen formation should be identified and a fuzzy expert system should be used to analyze the behavior of the yeast.

Gut, 1994 Jan, 35(1), 73 - 6
Butyrate oxidation is impaired in the colonic mucosa of sufferers of quiescent ulcerative colitis; Chapman MA et al.; The short chain fatty acids, acetate, propionate, and butyrate are produced by colonic bacterial fermentation of non-starch polysaccharides . Butyrate is the major fuel source for the colonic epithelium and there is evidence to suggest that its oxidation is impaired in ulcerative colitis . Triplicate biopsy specimens were taken at colonoscopy from five regions of the large bowel in 15 sufferers of ulcerative colitis . These patients all had mild or quiescent colitis as assessed by clinical condition, mucosal endoscopic and histological appearance . The rate of oxidation of glucose, glutamine, and butyrate through to carbon dioxide was compared with that in biopsy specimens from 28 patients who had no mucosal abnormality . Butyrate (272 (199-368)) was the preferred fuel source for the colitic mucosa followed by glutamine (33 (24-62)) then glucose (7.2 (5.3-15)) pmol/micrograms/hour; medians and 95% confidence intervals, p < 0.01 . There was no regional difference in the rate of utilisation of these metabolites . In the group with colitis the rate of butyrate oxidation to carbon dioxide was significantly impaired compared with that in normal mucosa decreasing from 472 (351-637) pmol/micrograms/hour to 272 (199-368) pmol/micrograms/hour; median and 95% confidence intervals, p = 0.016 . The rate of glucose and glutamine utilisation were not significantly different between normal and colitic mucosa . These data confirm that in quiescent ulcerative colitis there is an impairment of butyrate oxidation.

Am J Epidemiol, 1994 Jan 1, 139(1), 16 - 29
Calcium, vitamin D, dairy foods, and the occurrence of colorectal adenomas among men and women in two prospective studies; Kampman E et al.; A high intake of calcium, vitamin D, or specific dairy products is thought to reduce the incidence of colorectal cancer . The association of these nutrients and foods with the occurrence of colorectal adenomas, precursors of cancer, was studied in two large US cohort studies . Cases were patients with a diagnosis of adenomatous polyps of the left colon or rectum (331 men, 1986-1990; 350 women, 1980-1988), and controls were persons with endoscopic findings negative for adenoma (9,159 men and 8,585 women) . After adjustment for age, total energy, family history of colorectal cancer, body mass index, alcohol consumption, folate, intake of saturated fat and fiber, indications for endoscopy, and previous endoscopy, total calcium intake was not associated with the risk for adenoma (relative risk (RR), highest vs . lowest quintile of intake: men, 1.13, 95% confidence interval (CI) 0.76-1.66; women, 1.17, 95% CI 0.81-1.69) . Total vitamin D intake was unrelated to the risk for adenoma in men (RR = 1.29, 95% CI 0.87-1.93) . An inverse nonsignificant association was observed in women in the 1980-1988 analyses (RR = 0.68, 95% CI 0.41-1.13, trend p = 0.09), mainly attributable to the intake of multivitamin supplements, but an analysis of 4-year data (1984-1988) using a more detailed dietary assessment showed no association with vitamin D (RR = 1.04, 95% CI 0.65-1.67) . Milk consumption and intake of total fermented dairy products were not related to adenoma risk . In conclusion, the occurrence of colorectal adenoma was neither related to calcium intake nor to milk consumption, whereas vitamin D from supplements but not diet was slightly, but not significantly, inversely associated with risk among women only.

Mol Gen Genet, 1994 Jan, 242(1), 57 - 64
Analysis of the regulation of penicillin biosynthesis in Aspergillus nidulans by targeted disruption of the acvA gene; Brakhage AA et al.; To analyse the regulation of the biosynthesis of the secondary metabolite penicillin in Aspergillus nidulans, a strain with an inactivated acvA gene produced by targeted disruption was used . acvA encodes delta-(L-alpha-aminoadipyl)-L-cysteinyl-D-valine synthetase (ACVS), which catalyses the first step in the penicillin biosynthetic pathway . To study the effect of the inactivated acvA gene on the expression of acvA and the second gene, ipnA, which encodes isopenicillin N synthase (IPNS), A . nidulans strain XEPD, with the acvA disruption, was crossed with strain AXB4A carrying acvA-uidA and ipnA-lacZ fusion genes . Ascospores with the predicted non-penicillin producing phenotype and a hybridization pattern indicating the presence of the disrupted acvA gene, and the fusion genes integrated in single copy at the chromosomal argB locus were identified . Both fusion genes were expressed at the same level as in the non-disrupted strain . Western blot analysis (immunoblotting) revealed that similar amounts of IPNS enzyme were present in both strains from 24 to 68 h of a fermentation run . In the acvA disrupted strain, IPNS and acyl-CoA: 6-aminopenicillanic acid acyltransferase (ACT) specific activities were detected, excluding a sequential induction mechanism of regulation of the penicillin biosynthesis gene ipnA and the third gene aat.

J Urol, 1994 Jan, 151(1), 125 - 6
Gas in hepatic veins: a rare and critical presentation of emphysematous pyelonephritis; Chen KW et al.; Although emphysematous pyelonephritis has been recognized for more than a hundred years, the actual etiology is still unknown . Glucose fermentation has been implicated as a mechanism of gas formation . We report a case of emphysematous pyelonephritis in which real-time ultrasonography demonstrated intravascular gas bubbles originating in the involved kidney, and passing into the inferior vena cava and hepatic veins . Gas from the affected kidney was analyzed by chromatography; the result showed hydrogen 10.5%, carbon dioxide 39%, nitrogen 49.6% and oxygen 0.8% . The clinical presentation and the results of gas analysis implicate a critical condition that bacteria proliferated rapidly by mixed acid fermentation of glucose . Additionally, the finding of gas production and transportation could explain the previous hypothesis of gas transport . In this critical situation immediate drainage with medical intervention is indicated to treat this life threatening condition.

Yeast, 1994 Jan, 10(1), 59 - 65
Transport of hexoses in yeast . Re-examination of the sugar phosphorylation hypothesis with a new experimental approach; Nevado J et al.; The constitutive transport of hexoses in yeast has been re-examined with a new radioactive experimental approach devised to distinguish between association or independence of the transport step with phosphorylation of the sugar substrate . The approach takes advantage of the fact that the label of {2-3H}mannose disappears once it has been phosphorylated by the yeast, due to its conversion to fructose-6-phosphate . Our results with wild-type yeast and this fermentable sugar support the view that the transport of hexoses in yeast does not involve phosphorylation of the substrate . Other features of the transport process have been examined using this experimental procedure and are also reported.

Voen Med Zh, 1994 Jan, (1), 52 - 4, 80
{The information value of biotesting and chemiluminescence methods in evaluating drinking water quality}; Kutsenko SA et al.; The article studies the informative value of test objects for the evaluation of potable water which contains toxic substances . A number of test objects is proposed by the authors to estimate the chemical harmlessness of water: tetrachimens, Daphnia and peroxide ferment system . The data obtained with the help of test-objects possess a sufficient selective sensibility as far as maximum allowable concentration of various toxic substances is concerned . The authors stress that these methods of biological testing may complement or precede the traditional methods of water evaluation.

Clin Ter, 1994 Jan, 144(1), 31 - 42
{Critical evaluation of phytothermotherapy ("hay baths") in degenerative arthropathies}; Miori R et al.; It is a traditional practice of the Alpine region of Trentino and Alto Adige to use phytothermotherapeutic treatment with fermenting grass ("hay baths") for chronic degenerative arthropathies . A marked lack of clinical validation is however to be found in current literature as to its efficacy and tolerability . To verify these two aspects 27 patients (mean age 59 +/- 8.7 years, range 43-82) with osteoarthritis (15 of them with a generalized form) were evaluated before and after a ten-day treatment with immersion of the whole body in a bed made with fermenting grass according to the traditional method . The following clinical features were considered: pain in affected joints evaluated by visual analog scale, presence of global subjective improvement (or lack of it) immediately and 6 months after treatment, degree of global functional impairment, stiffness duration, handgrip strength . The mean score at the affected joints (on the visual analog pain scale) was 2.51 +/- 0.71 before and 1.83 +/- 0.89 after treatment (p < 0.001), with improvement in 68% of patients . Morning stiffness was reduced from 38.9 +/- 30.5 to 17.5 +/- 17.2 minutes (p < 0.05), with improvement in 57% of patients . Grip strength measure went from 136 +/- 59.7 to 147 +/- 51 mmHg (p < 0.01), with improvement in 77% of patients . Forty-eight percent of the patients were reassigned to better class of functional capacity (p < 0.001) . Patient general assessment signaled improvement in 72% of cases immediately after treatment, and in 80% after six months . Tolerability was high in 23 out of 25 patients, nobody was taken off treatment because of side effects, in two cases a one day interval due to asthenia was introduced . In conclusion, improvement rates were found higher when compared with controlled trials on efficacy of nonsteroidal antiinflammatory drugs . Noteworthy is also the persistence of improvement 6 months after treatment compared to the above mentioned drugs and usual physiokinesitherapeutic treatments.

JPEN J Parenter Enteral Nutr, 1994 Jan-Feb, 18(1), 4 - 8
Famine, fiber, fatty acids, and failed colonic absorption: does fiber fermentation ameliorate diarrhea?
Roediger WE.
The salvage function of the colon for absorption of unabsorbed sodium and water from the jejunum and ileum depends upon the metabolic integrity of colonic epithelial cells maintained by luminal short-chain fatty acids . With the depletion of luminal short-chain fatty acids under conditions of starvation, metabolic compensation from vascular substrates is incomplete . Loss of luminal short-chain fatty acids diminishes cell membrane integrity and causes secretion by colonic epithelial cells, leading to starvation diarrhea . Because sodium absorption is dependent upon CO2 production from n-butyrate, no compensatory absorption occurs during starvation . Under conditions in which luminal short-chain fatty acids are depleted, dietary fiber is useful as a low osmolality food constituent and for renewal of short-chain fatty acid levels by bacterial fermentation . The "antisecretory" effect of dietary fiber depends on the degree of the preexisting depletion of short-chain fatty acids and the methodology used to assess absorptive function . Dietary fiber has not been found harmful in refeeding starvation victims for whom it is an essential food constituent.

Vet Med (Praha), 1994, 39(1), 11 - 22
{The effect of cadmium on the protozoan population and rumen fermentation of feed in an artificial rumen}; Jalc D et al.; In our experiment, the effects of 5, 10 and 20 mg cadmium per kg dry matter (DM) on protozoan population and rumen fermentation of feed ration consisting of 11.7 g DM of hay and 2.8 g DM of barley (80: 20%) were followed in artificial rumen (Rusitec) . The results of the experiment showed that the addition of 5 and 10 mg cadmium per kg DM less significantly (P < 0.05) decreased the digestibility of DM, organic matter and neutral detergent fibre and significantly (P < 0.01) decreased the digestibility of cellulose of feed ration . It is interesting that the addition of 20 mg cadmium per kg DM did not influence these parameters . Although the total gas production showed a tendency of decrease due to the influence of the addition of 5, 10 and 20 mg cadmium/kg DM, methane and CO2 production was not altered . However, cadmium significantly influenced the production of individual volatile fatty acids-VFA's (mmol/day) . The addition of 5, 10 and 20 mg cadmium per kg DM significantly increased acetic acid production (by 10-20%) and decreased propionic acid production (by 18-30%) . Therefore, the acetate: propionate ratio was significantly increased (from 1.57 to 2.45-2.60) by the addition of cadmium . The production of n-valeric and iso-valeric acids was also significantly decreased in comparison with the control . The decrease of individual VFA's was more significant at the higher amount of cadmium added into the fermentation system . The proportions of individual VFA's in total VFA production expressed in molar % showed a similar character . The changes in the production of individual VFA's due to the influence of the addition of 5, 10 and 20 mg cadmium per kg DM caused a decrease in energetic efficiency of VFA's (P < 0.001) in comparison with the control . The other parameters of rumen fermentation - utilization of glucose, adenosine triphosphate (ATP) production, fermented hexose, fermented amino acids and fermented organic matter (OMF) were not influenced by the cadmium addition . Although the total microbial matter production in effluent and undigested feed (residues) was significantly (P < 0.001) decreased by the addition of 5, 10 and 20 mg cadmium per kg DM, the efficiency of microbial synthesis expressed as YATP and g microbial N/kg OMF was not changed and achieved the values 11.78-12.68 (YATP), 25.56-28.35 (g microbial N/kg OMF), respectively . The total protozoan population was significantly decreased by the cadmium addition mainly as a result of the decrease of infusoria of Entodinium spp.(ABSTRACT TRUNCATED AT 400 WORDS)

Parasitol Res, 1994, 80(1), 10 - 5
Inhibitory activity of saccharomyces yeasts on the adhesion of Entamoeba histolytica trophozoites to human erythrocytes in vitro; Rigothier MC et al.; Adhesion to target cells represents the first step in infection by Entamoeba histolytica . Binding of axenic amoeba (HMI strain) to human red cells in vitro was employed as a model of the adhesion process . The influence of precontact of trophozoites with suspensions of live Saccharomyces boulardii yeasts, their fractions (membranes and yeast-content supernatant before and after filtration to eliminate the membrane) or yeast culture medium before and after fermentation was investigated . N-Acetylgalactosamine (GalNAC) was employed as the reference inhibitory sugar . The percentage of amoebae bearing red cells after pretreatment of amoebae with the various suspensions and derivates was determined . Adhesion was also evaluated by scanning electron microscopy (SEM) . Pretreatment of amoebae with the live yeast suspension led to a significant reduction in the percentage of adhesion {32% vs 70% in the phosphate-buffered saline (PBS) control} . Reduced adhesion was also observed with the filtered and unfiltered supernatant of the yeast suspension homogenate {32% and 34%, respectively, vs 69% in the PBS control}, yeast culture medium at the end of fermentation {49% vs 76% in the PBS control} and GalNAC {32% vs 72% in the PBS control} . SEM showed a decrease in the number of amoebae bearing red cells and a reduction in the number of red cells adhering to amoebae . We conclude that substances produced by the yeasts compete with red cells for adhesion sites on amoebae.

Z Naturforsch {C}, 1994 Jan-Feb, 49(1-2), 132 - 8
Two inhibitors of platelet aggregation from a Panus species (Basidiomycetes); Lorenzen K et al.; Two inhibitors of platelet aggregation were isolated from fermentations of Panus sp . 9096 . One inhibitor proved to be identical to naematolon (2), an antibiotic previously isolated by S . Backens et al . from several Hypholoma species . The other metabolite, panudial (1), is a new nordrimane (cis-annelation of the bicyclus) lacking the carbon atom in position 10 of the drimane skeleton . Panudial is a potent inhibitor of bovine and human platelet aggregation stimulated by different inducers.

Plant Foods Hum Nutr, 1994 Jan, 45(1), 81 - 9
Preparation and fermentation of rice-defatted soy flour blends: effect on protein, fat and ash content; Goyal R et al.; Rice-defatted soy flour blends prepared in three proportions viz . 40:60, 50:50 and 60:40 were fermented with buttermilk at 25, 30 and 35 degrees C for 12, 18 and 24 h . Fermentation of these blends lowered the pH and raised the titratable acidity, maximum drop in pH and rise in titratable acidity being observed at 35 degrees C for 24 h . The fermentation either decreased or did not change the protein content of cereal-legume blends . Fat as well as ash content remained unaltered irrespective of temperature and time period of fermentation.

Plant Foods Hum Nutr, 1994 Jan, 45(1), 23 - 34
Evaluation of the effect of processing techniques on the nutrient and antinutrient contents of pearl millet (Pennisetum glaucum) seeds; Obizoba IC et al.; This work was undertaken to evaluate the effect of soaking, sprouting, cooking and fermentation or their combinations on the nutrient and antinutrient contents of pearl millet seeds . Standard assay procedures were adopted to determine both the nutrient and the antinutrient concentrations of the products . The synergistic effect of cooking and fermentation improved the nutrient quality . The antinutrients were reduced to safe levels to a greater extent than did any of the other processing techniques or their combinations employed.

J Appl Bacteriol, 1994 Jan, 76(1), 55 - 61
Competition between reductive acetogenesis and methanogenesis in the pig large-intestinal flora; De Graeve KG et al.; Washed bacterial suspensions obtained from the pig hindgut were incubated under 13CO2 in a buffer containing NaH13CO3 and carbohydrates . Incorporation of 13C into short chain fatty acids was assayed by quantitative nuclear magnetic resonance . The effects of different levels of H2 added to the gas phase (0, 20 and 80% v/v) and of the specific methanogenesis inhibitor 2-bromoethane-sulphonic acid (BES) were determined . In control incubations increasing the concentration of H2 markedly increased methane production . Single- and double-labelled acetate and butyrate were formed in all incubations . In the absence of BES, increasing H2 significantly increased the incorporation of 13CO2 into butyrate and the proportion of double-labelled acetate in total labelled acetate . The addition of BES proved to be very successful as a methane inhibitor and greatly enhanced the amount of mono- and double-labelled acetate, especially at the highest H2 partial pressure . The results suggest that methanogenesis inhibited both routes of reductive acetogenesis, i.e . the homoacetate fermentation of hexose (represented for the most part by single labelling) and the synthesis of acetate from external CO2 and H2 (represented mostly by double labelling) . A highly significant interaction between BES and H2 concentration was observed . At the highest pH2 BES increased the proportion of labelled acetate in total acetate from 17.1% for the control to 50.9% . It was concluded that although acetogenesis and methanogenesis can occur simultaneously in the pig hindgut, reductive acetogenesis may become a significant pathway of acetate formation in the absence of methanogenesis.

Stem Cells, 1994 Jan, 12(1), 7 - 12
The design and synthesis of a new anticancer drug based on a natural product lead compound: from neplanocin A to cyclopentenyl cytosine (CPE-C); Driscoll JS et al.; In 1979, an unusual, carbocyclic nucleoside was discovered in a Japanese fermentation broth and designated neplanocin A . This compound is an analog of adenosine possessing a cyclopentene-containing "sugar" glycon . Although neplanocin A was biologically active, it was quite toxic . It therefore became a lead compound for analog synthesis in an attempt to maximize antitumor and antiviral activity while minimizing toxicity . First, a total synthesis of naturally occurring (-)-neplanocin A was accomplished using a new, versatile cyclopentenone carbocyclic "sugar" intermediate . This intermediate was then used to synthesize some 20 purine and pyrimidine analogs of neplanocin A which were evaluated for their antitumor and antiviral properties . Among the purine analogs, 3-deazaneplanocin A, a powerful inhibitor of S-adenosylhomocysteine hydrolase, was found to have excellent antiviral activity both in vitro and in vivo . Cyclopentenyl cytosine (CPE-C) was found to be the most biologically active compound among the carbocyclic pyrimidine nucleosides . In addition to activity against over 20 viruses, this compound had excellent preclinical antitumor activity against both murine leukemias and human tumor xenografts . CPE-C is currently under clinical evaluation as an anticancer drug.

Biotechniques, 1994 Jan, 16(1), 140 - 7
Stable, continuous large-scale production of human monoclonal HIV-1 antibody using a computer-controlled pilot plant; Unterluggauer F et al.; A completely automated pilot plant used for fermentation has been employed with direct digital control (DDC) technology for monitoring and regulating growth of human cells . A human hybridoma cell line (3D6) producing anti-human immunodeficiency virus (HIV)-1 antibodies was used as a model for large-scale production (300-liter airlift fermentor) in continuous culture . Parameters controlled were pH, dissolved oxygen, temperature and the flow rate of four gases used in the process . A control strategy was implemented to achieve constant fluid velocity and mixing by maintaining the rate of gas flow at a constant level . Another advantage of this approach was that the total gas flow required for optimal fluid circulation was reduced from 1 volume gas/volume fermenter/hour (vvh) to 0.3 vvh . Use of a low flow rate eliminated the serious problems of foaming, which contributed significantly to cell destruction, shorter filter-life and other considerations . Dilution rate was optimized at laboratory scale for maximum productivity, which results in relatively low viability . At a dilution rate of 0.0076 h-1, a total cell density of 6-7 x 10(5) cells/ml with a viability of approximately 75% was maintained during long-term continuous cultivation . These growth conditions resulted in a product titer stabilized in the range of 35 micrograms IgG/ml . Batchwise purification was achieved with a recovery of more than 50% and a final purification of active monoclonal antibody representing about 99% product . Results from isoelectric focusing and Western blotting demonstrated batch-to-batch consistency of the purified human monoclonal antibody to HIV-1 during the continuous growth process.(ABSTRACT TRUNCATED AT 250 WORDS)

Dtsch Tierarztl Wochenschr, 1994 Jan, 101(1), 16 - 8
{Effects of orally administered therapeutic drugs on the fermentation processes in the rumen fluid of ruminating cattle (in vitro) . 6 . Copper sulfate}; Odenkirchen S et al.; In 50 trials, incubating rumen fluid at 39 degrees C for 6 hours with starch and urea as nutrients, the effects of simulated oral administration of 3 g copper sulphate per animal and day (50 mg copper sulphate per liter rumen fluid) on rumen fermentation patterns have been examined . In two series of five incubations each in rumen fluid of five donors (total = 50), doses of 2.25 g (37.5 mg/l) and 4.5 g (75 mg/l) copper sulphate were simulated . The five donors (517-720 kg) of ruminal fluid were fed a ration of hay and concentrate twice daily and water was offered ad libitum . Rumen fluid was sampled 2.5 hours after feeding in the morning and immediately incubated in the artificial rumen . While at 2.25 g an effect was hardly seen and 4.5 g were followed by great changes, 3 g appeared to be the limiting dose that reduced the amylolysis (-23.9%; p < 0.001), the production of volatile fatty acids (-23.5%; p < 0.001) and methane (-23.6%; p < 0.001), but caused a higher concentration of ammonia (+11.2%; p < 0.001) . Therefore 2 g CuSO4/animal/day is recommended as maximum dose in cattle to overcome Cu-deficiency.

Reprod Nutr Dev, 1994, 34(1), 47 - 56
Effects of 3 chemical treatments on in vitro fermentation of rice straw by mixed rumen microbes in the presence or absence of anaerobic rumen fungi; Cann IK et al.; Rice straw (Rs) was treated by a sodium chlorite/acetic acid mixture (Sct), ammoniation (At) and alkaline hydrogen peroxide (Athp) methods . The objective was to compare their degradation and fermentation products in the presence or suppression of anaerobic fungi . Significant differences (P < 0.01) in degradation of straws were observed during all periods of incubation with Sct having the highest digestibilities during the 48-h and 72-h incubations . The degradation of Sct straw was highest in both of the incubations with whole rumen fluid (WRF) and WRF plus cycloheximide . In sacco digestion followed the order of Sct > At > Rs > Athp . Suppressing fungal activity with cycloheximide resulted in a decrease in dry matter degradation, with concomitant decrease in total volatile fatty-acid concentration . While the suppression of fungal activity with cycloheximide depressed acetate and butyrate production, it favored an increase in propionate production.

Appl Biochem Biotechnol, 1994 Jan, 44(1), 49 - 64
Kinetics of ethanol production from carob pods extract by immobilized Saccharomyces cerevisiae cells; Roukas T; Kinetics of ethanol production from carob pods extract by immobilized S . cerevisiae cells in static and shake flask fermentation have been investigated . Shake flask fermentation proved to be a better fermentation system for the production of ethanol than static fermentation . The optimum values of ethanol concentration, ethanol productivity, ethanol yield, and fermentation efficiency were obtained at pH range 3.5-6.5 and temperature between 30-35 degrees C . A maximum ethanol concentration (65 g/L), ethanol productivity (8.3 g/Lh), ethanol yield (0.44 g/g), and fermentation efficiency (95%) was achieved at an initial sugar concentration of 200, 150, 100, and 200 g/L, respectively . The highest values of specific ethanol production rate and specific sugar uptake rate were obtained at pH 6.5, temperature 40 degrees C, and initial sugar concentration of 100 g/L . Other kinetic parameters, biomass concentration, biomass yield, and specific biomass production rate were maximum at pH 5.5, temperature 30 degrees C, and initial sugar concentration 150 g/L . Under the same fermentation conditions non-sterilized carob pod extract gave higher ethanol concentration than sterilized medium . In repeated batch fermentations, the immobilized S . cerevisiae cells in Ca-alginate beads retained their ability to produce ethanol for 5 d.

Gut, 1994 Jan, 35(1 Suppl), S23 - 7
Bacterial translocation: the influence of dietary variables; Deitch EA; Transmucosal passage of bacteria in critically ill patients may lead to a significant incidence of systemic sepsis . This has attracted much clinical interest, as it has been shown that malnutrition in itself, impairs various aspects of barrier function . Bacterial translocation is increased in animal models where nutrients are given by the parenteral route, while enteral feeding reverses this . Translocation is also considerably increased in response to a non-lethal endotoxin challenge, if there is pre-existing protein energy malnutrition . Similar results have been obtained where the insult is caused by the inflammatory agent, zymosan . Dietary fibre reduces the deleterious effects of either agent on translocation, although the type of fibre is important . Bulk forming but non-fermentable fibres are more effective than easily fermentable types (for example, pectin) . Glutamine was not effective in preventing elemental diet induced bacterial translocation . Thus, although fermentable fibre and glutamine have positive effects on mucosal mass, they do not affect translocation . Enteral nutrition thus seems to be superior to parenteral nutrition in maintaining the functional barrier of the gut . A clearer understanding of the physiology of these effects may lead to use of specifically modified enteral diets in the critically ill patient.

FEMS Microbiol Lett, 1994 Jan 1, 115(1), 51 - 5
Chemotrophic growth of heliobacteria in darkness; Kimble LK et al.; Conditions are described that support anaerobic dark chemotrophic growth of heliobacteria . Growth was pyruvate-dependent and was best in well-buffered pyruvate media supplemented with yeast extract . Heliobacterial cells grown in darkness synthesized bacteriochlorophyll g and carotenoids and fermented pyruvate to acidic products, CO2, and in some cases, H2 . All recognized species of heliobacteria as well as several newly isolated strains were capable of dark anaerobic growth, suggesting that this growth mode may be ecologically important for survival of these organisms in their soil habitat.

Occup Environ Med, 1994 Jan, 51(1), 54 - 6
Clinical reactions to Aspergillus niger in a biotechnology plant: an eight year follow up; Seaton A et al.; The manufacture of citric acid by fermentation of molasses with Aspergillus niger has previously been described as a cause of occupational asthma in a factory . A longitudinal survey of the workforce of this factory has been carried out from 1984 to 1991 . Over this period 160 of the original 278 workers left the workforce, together with 39 of 76 new recruits . Partial enclosure of the process and exhaust ventilation, installed in 1984, was effective in preventing any new cases of occupational asthma over the eight year period, and no new skin sensitisation was detected . Spore counts of A niger averaged about 100 times those in the outside air . Health in the 1984 survey had a striking influence on subsequent retiral; only 11 of the 79 with respiratory symptoms remained in 1991, compared with 90 of the 182 with no symptoms . In conclusion A niger is a weak antigen and simple hygiene measures protect the workforce . Exclusion of recruits with positive skin tests is not necessary if such measures are taken . The survey provided evidence of the selection factors operating within a workforce over this period contributing to retiral of the less healthy.

Int J Syst Bacteriol, 1994 Jan, 44(1), 87 - 93
Lachnospira pectinoschiza sp . nov., an anaerobic pectinophile from the pig intestine; Cornick NA et al.; Pectinophiles are bacteria that utilize pectin and only a few related compounds as substrates . Obligately anaerobic pectinophiles have been isolated from the intestinal tracts and gingivae of humans and from the rumina of cattle . We isolated three strains of pectinophilic bacteria from colonic contents of pigs but were unable to isolate pectinophiles from the rumen contents of four sheep, even when the animals were fed a high-pectin diet . The pectinophiles isolated from pigs were strictly anaerobic, motile, gram-positive rods (0.36 to 0.56 by 2.4 to 3.1 microns) . Pectin, polygalacturonic acid, and gluconate were the only substrates that supported rapid growth . All three strains grew slowly on either lactose or cellobiose and fermented fructose after a lag of several days . Pectin was degraded by means of an extracellular pectin methylesterase and a Ca(2+)-dependent exopectate lyase . A comparison of the 16S rRNA sequences of these isolates with the 16S rRNA sequences of other gram-positive bacteria revealed a specific relationship with Lachnospira multipara (level of similarity, 94%) . The Gram reaction, formation of spore-like structures, and the utilization of lactose and cellobiose differentiated the pig isolates from previously described pectinophiles . The pig isolates represent a previously undescribed species of the genus Lachnospira, for which we propose the name Lachnospira pectinoschiza.

J Dairy Sci, 1994 Jan, 77(1), 217 - 29
Effects of forage particle size and long hay for cows fed total mixed rations based on alfalfa and corn; Fischer JM et al.; A 2 x 2 factorial arrangement of treatments, in which particle length of alfalfa silage in the TMR and supplementary long alfalfa-grass hay were the factors, was used to determine whether hay benefits lactating cows and whether its effects depend on fibrosity of the main forage source . Without supplementary hay, TMR contained 45% forage, including corn silage, and 26 to 27.5% NDF . When hay was fed, the amount of alfalfa silage in the corresponding TMR was reduced . In the production trial, 40 cows (20 multiparous) were fed the diets for 8 wk in early lactation . No interactions of silage length and hay occurred on any production variables except lactose concentration in the milk of multiparous cows . Addition of hay to the diet enhanced DMI, without effect on production, so efficiency of milk production was reduced . Shorter alfalfa silage enhanced DMI by multiparous cows, reduced SCM and FCM in primiparous cows, and depressed fat test in both groups . Milk composition and component production generally were unaffected . Five rumen-fistulated cows in early to midlactation each were given the four treatments during four 3-wk periods . Hay enhanced rumination when short alfalfa silage was fed but tended to reduce it on long alfalfa silage . Hay also depressed rumen pH and enhanced VFA concentrations . Alfalfa silage length had minimal effects on rumination and no effect on fermentation, and neither hay nor silage length affected digestion of silage DM or NDF in the rumen . Addition of hay to the diet may not be beneficial for cows fed TMR, but longer term feeding studies are needed.

J Dairy Sci, 1994 Jan, 77(1), 205 - 16
Effects of beet pulp and animal by-products on milk yield and in vitro fermentation by rumen microorganisms; Mansfield HR et al.; Forty-six Holstein cows (30 primiparous) were assigned to one of four dietary treatments arranged as a 2 x 2 factorial experiment during wk 4 to 17 of lactation . Main effects were corn versus dried sugar beet pulp and soybean meal versus animal by-product meal (mixture of meat and bone meal, feather meal, and blood meal) . Beet pulp replaced half of the corn at 15% of dietary DM . Diet DM (mean of four treatments) contained 18% alfalfa pellets, 17.4% alfalfa hay, 17.2% corn silage, and 47.1% concentrate . Milk yield did not differ among treatments (mean 32.0 kg/d) . Dry matter intake, milk CP percentage, and milk CP yield decreased 5.6, 3.7 and 5.2%, respectively, but milk fat percentage increased 4.7% when beet pulp replaced corn . Animal by-products did not affect DMI or milk fat, but milk CP percentage decreased 3.0% . The same diets were evaluated in a continuous culture system . Fungal extract (Aspergillus oryzae), added as the third treatment, had little effect on fermentation . Digestion of DM, OM, NDF, and ADF were not affected by dietary treatments . Molar proportion of acetate was greater when corn was replaced by beet pulp . Although flow of NAN from fermenters increased by 3.2% with beet pulp and 3.1% with animal by-products, milk CP percentages decreased.

J Antibiot (Tokyo), 1994 Jan, 47(1), 64 - 71
Aqueous acetylation of desacetyl glutaryl 7-aminocephalosporanic acid (7ACA) and speculation on the origin of desacetyl cephalosporin C in fermentation broth; Wildfeuer ME; Acetylation of desacetyl glutaryl 7-aminocephalosporanic acid (7ACA), an intermediate in the two-stage enzymatic cleavage of cephalosporin C, has been accomplished in aqueous media with acetic anhydride . Because the reaction is done in water, conversion of desacetyl glutaryl 7ACA to glutaryl 7ACA can be accomplished at an early stage in the purification process . Evidence is presented that desacetyl cephalosporin C in cephalosporin C broth is formed from the mycelial catalyzed hydrolysis of cephalosporin C.

J Antibiot (Tokyo), 1994 Jan, 47(1), 46 - 53
Arohynapenes A and B, new anticoccidial agents produced by Penicillium sp . Taxonomy, fermentation, and structure elucidation; Masuma R et al.; Penicillium sp . FO-2295, a water isolate, was found to produce a series of new anticoccidial compounds . Two active compounds, designated arohynapenes A and B, were isolated from the fermentation broth of the producing strain by solvent extration and preparative HPLC . Arohynapene A was deduced to be (2E,4E)-5-(5-hydroxy-2,6,8-trimethyl-5,6,7,8-tetrahydronaphtale ne)-2,4- pentadienoic acid, and arohynapene B was (2E,4E)-5-(2-hydroxymethyl-6,8-dimethyl-5,6,7,8-tetrahydronapht alene)-2,4- pentadienoic acid . Arohynapenes inhibited the growth of Eimeria tenella in an in vitro assay using BHK-21 cells as a host . No schizont in the cells was observed at concentrations ranging above 35.0 microM and 7.0 microM for arohynapenes A and B, respectively.

J Antibiot (Tokyo), 1994 Jan, 47(1), 23 - 31
The soraphens: a family of novel antifungal compounds from Sorangium cellulosum (Myxobacteria) . I . Soraphen A1 alpha: fermentation, isolation, biological properties; Gerth K et al.; An antifungal activity was detected in the culture broth of Sorangium cellulosum (Myxococcales), strain So ce26 . The activity was excreted into the supernatant during the log and early stationary phase . The active substance was quantitatively bound to XAD absorber resin added to the medium at the beginning of the fermentation . The new secondary metabolite was called soraphen and is of special interest to plant disease control for its inhibitory activity against numerous phytopathogenic fungi.

FEMS Microbiol Rev, 1994 Jan, 13(1), 25 - 58
The biological degradation of cellulose; Beguin P et al.; Cellulolytic microorganisms play an important role in the biosphere by recycling cellulose, the most abundant carbohydrate produced by plants . Cellulose is a simple polymer, but it forms insoluble, crystalline microfibrils, which are highly resistant to enzymatic hydrolysis . All organisms known to degrade cellulose efficiently produce a battery of enzymes with different specificities, which act together in synergism . The study of cellulolytic enzymes at the molecular level has revealed some of the features that contribute to their activity . In spite of a considerable diversity, sequence comparisons show that the catalytic cores of cellulases belong to a restricted number of families . Within each family, available data suggest that the various enzymes share a common folding pattern, the same catalytic residues, and the same reaction mechanism, i.e . either single substitution with inversion of configuration or double substitution resulting in retention of the beta-configuration at the anomeric carbon . An increasing number of three-dimensional structures is becoming available for cellulases and xylanases belonging to different families, which will provide paradigms for molecular modeling of related enzymes . In addition to catalytic domains, many cellulolytic enzymes contain domains not involved in catalysis, but participating in substrate binding, multi-enzyme complex formation, or possibly attachment to the cell surface . Presumably, these domains assist in the degradation of crystalline cellulose by preventing the enzymes from being washed off from the surface of the substrate, by focusing hydrolysis on restricted areas in which the substrate is synergistically destabilized by multiple cutting events, and by facilitating recovery of the soluble degradation products by the cellulolytic organism . In most cellulolytic organisms, cellulase synthesis is repressed in the presence of easily metabolized, soluble carbon sources and induced in the presence of cellulose . Induction of cellulases appears to be effected by soluble products generated from cellulose by cellulolytic enzymes synthesized constitutively at a low level . These products are presumably converted into true inducers by transglycosylation reactions . Several applications of cellulases or hemicellulases are being developed for textile, food, and paper pulp processing . These applications are based on the modification of cellulose and hemicellulose by partial hydrolysis . Total hydrolysis of cellulose into glucose, which could be fermented into ethanol, isopropanol or butanol, is not yet economically feasible . However, the need to reduce emissions of greenhouse gases provides an added incentive for the development of processes generating fuels from cellulose, a major renewable carbon source.

Schweiz Monatsschr Zahnmed, 1994, 104(8), 941 - 5
Clinical caries studies with polyalcohols . A literature review; Imfeld TN; Polyalcohols represent the most important group of sugar substitutes . Those most widely used in products advertising dental benefits compared to their sucrose containing homologues are sorbitol, mannitol (hexitols), xylitol (pentitol), maltitol, lactitol (12-carbon polyols), Lycasin (hydrogenated starch hydrolysate) and Palatinit (mixture of two 12-carbon polyols) . All these polyalcohols have been proven to be non-cariogenic or extremely low cariogenic in rat caries experimentation, and some of them also in human clinical caries studies . They have also been shown to be non-acidogenic or hypoacidogenic in plaque pH telemetry . The low or non-cariogenicity of the above polyols can be termed a "passive" feature, because it is based on the fact that they are not, or only poorly and very slowly, fermented by the oral flora . More recent research, however, has also propagated "active", i.e . bacteriostatic and/or cariostatic properties of xylitol or mixtures of xylitol with other sugar substitutes . Such claims have not yet been substantiated in human caries trials.

J Comp Physiol {B}, 1994, 164(3), 173 - 8
Rate of digesta passage in the philippine flying lemur, Cynocephalus volans; Wischusen EW et al.; The rate of digesta passage was measured in five captive Philippine flying lemurs (Cynocephalus volans) . These animals were force fed capsules containing known quantities of either particulate or soluble markers . The volumes of the gastrointestinal tracts of three flying lemurs were determined based on the wet weight of the contents of each section of the gut . The mean rate of digesta passage was 14.37 +/- 3.31 h when determined using the particulate marker and 21.9 +/- 0.03 h when determined using the soluble marker . The values based on the particulate marker are between 2% and 10% of similar values for other arboreal folivores . The morphology of the gastrointestinal system of the Philippine flying lemur is similar to that of other hindgut fermenters . Flying lemurs have a simple stomach and a large caecum . The total gut capacity of the Philippine flying lemur is similar to that of other herbivores, but is slightly smaller than that of either the koala (Phascolarctos cinereus), a hindgut fermenter, or the three-toed sloth (Bradypus variegatus), a foregut fermenter . These data suggest that flying lemurs deal with the problems of a folivorous diet very differently than some other arboreal mammals . Phascolarctos cinereus and Bradypus variegatus may represent one extreme with Cynocephalus volans representing the other extreme along a continuum of foraging strategies that are compatible with the arboreal folivore lifestyle.

Arch Microbiol, 1994, 162(1-2), 103 - 7
Fermentative degradation of triethanolamine by a homoacetogenic bacterium; Frings J et al.; With triethanolamine as sole source of energy and organic carbon, a strictly anaerobic, gram-positive, rod-shaped bacterium, strain LuTria 3, was isolated from sewage sludge and was assigned to the genus Acetobacterium on the basis of morphological and physiological properties . The G+C content of the DNA was 34.9 +/- 1.0 mol % . The new isolate fermented triethanolamine to acetate and ammonia . In cell-free extracts, a triethanolamine-degrading enzyme activity was detected that formed acetaldehyde as reaction product . Triethanolamine cleavage was stimulated 30-fold by added adenosylcobalamin (co-enzyme B12) and inhibited by cyanocobalamin or hydroxocobalamin . Ethanolamine ammonia lyase, acetaldehyde:acceptor oxidoreductase, phosphate acetyltransferase, acetate kinase, and carbon monoxide dehydrogenase were measured in cell-free extracts of this strain . Our results establish that triethanolamine is degraded by a corrinoid-dependent shifting of the terminal hydroxyl group to the subterminal carbon atom, analogous to a diol dehydratase reaction, to form an unstable intermediate that releases acetaldehyde . No anaerobic degradation of triethylamine was observed in similar enrichment assays.

Vet Med (Praha), 1994, 39(4), 197 - 203
{A computerized numerical identification system for the diagnosis of bacteria isolated from raw animal food products}; Urbanova E et al.; Acceleration of bacteria identification and certain standardization of results in clinical, and also veterinary and food microbiology is enabled by use of commercial diagnostic sets and computer processing of their results . In the present paper, 80 bacterial strains isolated from animal sources in the department of food hygiene were used for assessment of two numerical identification systems (TNW and IDENTI) . They were isolated from primary cultures on End's, meat-peptone and blood agar (Imuna, HI-Media) under different culture regimes (37 degrees C/24 h, laboratory temperature/3 days, 7 degrees C/10 days) . A commercial diagnostic set ENTEROtest 1 and 2 (Lachema a.s., Brno, Czech Republic) was used for the purposes of diagnostics of gram-negative fermenting, oxidase-negative bacteria . Testing was performed according to the manufacturer's instructions by the culture of isolated strain . The test results were read continually after 6-hour (sugars) and 24-hour cultivation . Each strain was tested three times . Additional tests--oxidase, catalase, yellow pigment production . These commercial numerical identification systems were compared: IDENTI (supplied by Z . Svoboda, Jihlava; Lachema a.s., Brno) TNW (supplied by the Czech Collection of Microorganisms, Brno) Out of the total number of 80 isolated gram-negative bacteria 77 (96.25%) strains were, classified into the genera by both numerical systems . This result is in agreement with the percentage of identified strains by means of foreign commercial sets and numerical systems, which ranges from 93 to 99% in bacteria isolated from foods (Cox and Mercuri, 1979).(ABSTRACT TRUNCATED AT 250 WORDS)

Crit Rev Biotechnol, 1994, 14(2), 193 - 224
Food bioconversions and metabolite production using immobilized cell technology; Norton S et al.; This review explores recent advances in the use of immobilized cells for the production of metabolites used in the food industry, such as enzymes, amino acids, organic acids, alcohols, aroma compounds, polysaccharides, and pigments . Some food bioconversions such as fermentation of soy sauce and various hydrolysis are also considered . Special emphasis was placed on existing or potential industrial processes . This article also reports the effects of the reactor (configuration and working conditions), the immobilized cell physiological status (growing, nongrowing, or permeabilized), and of the carrier type, configuration, and size on the performance of immobilized cell systems . Compared with free cell fermentation, the main advantage of using immobilized cells is an increase in productivity, particularly in the case of continuous fermentation . For monoenzymatic reactions, nongrowing immobilized cells are often reported to exhibit a higher stability than free or immobilized enzymes.

Crit Rev Biotechnol, 1994, 14(2), 179 - 92
Immobilized cells in meat fermentation; McLoughlin AJ et al.; The immobilization of microbial cells can contribute to fermented meat technology at two basic levels . First, the solid/semisolid nature (low available water) of the substrate restricts the mobility of cells and results in spatial organizations based on "natural immobilization" within the fermentation matrix . The microniches formed influence the fermentation biochemistry through mass transfer limitations and the subsequent development and activity of the microflora . This form of immobilization controls the nature of competition between subpopulations within the microflora and ultimately exerts an effect on the ecological competence (ability to survive and compete) of the various cultures present . Second, immobilized cell technology (ICT) can be used to enhance the ecological competence of starter cultures added to initiate the fermentation . Immobilization matrices such as alginate can provide microniches or microenvironments that protect the culture during freezing or lyophilization, during subsequent rehydration, and when in competition with indigenous microflora . The regulated release of cells from the microenvironments can also contribute to competitive ability . The regulation of both immobilization processes can result in enhanced fermentation activity.

Nutr Health, 1994, 9(4), 289 - 302
Influence of mother's occupation and education on breast-feeding and weaning in infants and children in Makurdi, Nigeria; Igbedioh SO; The influence of Mother's Occupation and education on breastfeeding and weaning in infants and children in Makurdi was investigated . A pre-tested and validated standard questionnaire was used to collect data from 100 healthy randomly-selected mothers who regularly visited the post-natal health clinics in Makurdi . The result showed that occupation and education influenced the frequency and duration of breastfeeding, in addition to the nutritional quality and the type of weaning food fedPIP: Questionnaires were distributed in May and August of 1990 to 100 mothers attending two state government health clinics in Makurdi, Benue State, Nigeria, which has a population of 350,000 . Women in the study were aged 15-44 years and had children aged 6-31 months . About 55% of study participants were from Benue State which is comprised of Tiv, Idoma, and Igalla ethnic groups . 59% did not have more than a primary education . 12% had paid employment . Most lived in cement plastered houses with corrugated roofs, piped water, and electricity . 92% breast fed on demand; 80% had breast feedings at least six times a day, and 82% of infants had eight or more feedings with breast milk . Most mothers were self-employed or unemployed . Most, who were self-employed or unemployed, desired to stop breast feeding at 18-20 months and had feedings of over 15 minutes per episode . Salaried employees tended to wean at 3-4 months . Women with the lowest education or no education had the longest breast feeding times per episode of 42% nursing for 10-30 minutes compared to only 25% among the better educated . Less educated women also introduced supplemental foods later: 5-9 months compared to 3-5 months among the better educated . Early weaning at 1 week to 4 months was predominant among women with a college education (90%) or secondary education (95%) . Most fed their infants "akamu," a gruel made from fermented grains . Only 18%, of which many were college educated, introduced legumes as a first food . Many who did not feed their infants fruits or vegetables had no education or under a secondary school education . The use of milk formula appeared to be related to cost and higher educational level .

Nutr Cancer, 1994, 21(2), 113 - 31
Soy intake and cancer risk: a review of the in vitro and in vivo data; Messina MJ et al.; International variations in cancer rates have been attributed, at least in part, to differences in dietary intake . Recently, it has been suggested that consumption of soyfoods may contribute to the relatively low rates of breast, colon, and prostate cancers in countries such as China and Japan . Soybeans contain a number of anticarcinogens, and a recent National Cancer Institute workshop recommended that the role of soyfoods in cancer prevention be investigated . In this review, the hypothesis that soy intake reduces cancer risk is considered by examining relevant in vitro, animal, and epidemiological data . Soybeans are a unique dietary source of the isoflavone genistein, which possesses weak estrogenic activity and has been shown to act in animal models as an antiestrogen . Genistein is also a specific inhibitor of protein tyrosine kinases; it also inhibits DNA topoisomerases and other critical enzymes involved in signal transduction . In vitro, genistein suppresses the growth of a wide range of cancer cells, with IC50 values ranging from 5 to 40 microM (1-10 micrograms/ml) . Of the 26 animal studies of experimental carcinogenesis in which diets containing soy or soybean isoflavones were employed, 17 (65%) reported protective effects . No studies reported soy intake increased tumor development . The epidemiological data are also inconsistent, although consumption of nonfermented soy products, such as soymilk and tofu, tended to be either protective or not associated with cancer risk; however, no consistent pattern was evident with the fermented soy products, such as miso . Protective effects were observed for both hormone- and nonhormone-related cancers . While a definitive statement that soy reduces cancer risk cannot be made at this time, there is sufficient evidence of a protective effect to warrant continued investigation.

J Clin Pediatr Dent, 1994 Winter, 18(2), 139 - 42
The cost of nursing caries in a Native American Head Start population; Cook HW et al.; Nursing caries is a unique form of caries caused by prolonged exposure to pooled fermentable liquids and a lack of salivary flow during sleep . It is characterized by extensive destruction of the primary maxillary incisors generally beginning on the facial or lingual smooth surfaces . Nursing caries appears to have a particularly high prevalence in Native American populations and can be very costly to restore . The purpose of this study was (1) to determine the prevalence of nursing caries in a Mississippi Choctaw Indian Head Start program and (2) to determine the dollar costs of restoring nursing caries in a similar population . In part 1 of this study, 2 dentists independently examined 629 Native American Head Start children ranging in age from 3-5 years . It was found that 50.2% of these children had nursing caries . In part 2 of this study the cost of treating nursing caries in a Choctaw Indian population that ranged in age from 2-5 years was determined . It was found that the mean total cost of restoring a nursing caries patient requiring general anesthesia to provide treatment was $2,141.75 . It was also determined that the mean cost of providing treatment for those children not requiring general anesthesia was $311.55 . This study concluded that there was an extremely high prevalence of nursing caries in this Choctaw Indian Head Start population and that funds directed toward prevention would be a wise investment and that renewed and innovative efforts toward preventing nursing caries in these populations are indicated.

Reprod Nutr Dev, 1994, 34(3), 193 - 200
{Quantification of ammonia in a sample of rumen contents and fermentation with a gas diffusion electrode}; Broudiscou L et al.; The use of an electrode for the determination of ammonia in rumen and fermentor fluid samples has been evaluated . The amount of interfering volatile bases was negligible in our samples . The memory effect was only significant at the limits of the ammonia concentration range . The results from the electrode method were linearly correlated with the values from the standard colorimetric method (slope = 1.009; R = 0.998).

Microbiol Immunol, 1994, 38(2), 103 - 7
Purification and characterization of an acid phosphatase from Mycoplasma fermentans; Noda M et al.; An acid phosphatase associated with the cell membranes of Mycoplasma fermentans was released from the membranes with Triton X-100, then purified by ion-exchange chromatography on DEAE-Sephacel and CM-Sepharose, followed by affinity chromatography on Con A-Sepharose . Sodium dodecyl sulfate-polyacrylamide gel electrophoresis of the purified enzyme revealed a single band with a molecular mass of 31.2 kilodaltons . The enzyme activity toward p-nitrophenyl phosphate was enhanced remarkably by Cu2+, Co2+ and Mg2+, but the activity was not inhibited by EDTA . The enzyme dephosphorylated O-phospho-L-tyrosine as well as p-nitrophenyl phosphate, but not O-phospho-L-threonine, O-phospho-L-serine, glucose-1-phosphate, phosphoryl choline and adenosine triphosphate . The level of the O-phospho-L-tyrosine phosphatase activity was the highest in Mycoplasma faucium and the second highest in Mycoplasma fermentans of all tested human mycoplasmas.

Curr Opin Periodontol . 1994;:78-86.
Root surface caries; Ravald N; Epidemiologic studies have shown that root surface caries are present worldwide . The prevalence and incidence of root surface caries differ widely among different populations but also among individuals within the same group . Differences in diagnostic criterias and reporting of data substantially influence epidemiologic data . The prevalence of decayed and filled root surfaces generally increases with age . However, age per se is not considered to be the main reason for caries development on root surfaces . The same main factors as for coronal caries, ie, cariogenic microorganisms, diet, saliva, and fluoride exposure, seem to play important roles in root caries development . Due to different anatomy, histology, and chemical composition of the tissues, there may be a higher risk of caries development on root surfaces than on coronal surfaces . In treatment of root surface caries, a causative treatment strategy should be determined . Prevention and treatment should focus on oral hygiene, fluoride exposure, and restriction of intake frequency of foods containing sugars or other easily fermentable carbohydrates.

EXS, 1994, 71, 185 - 95
Helicobacter pylori alcohol dehydrogenase; Salaspuro M; We have recently shown that 34 different Helicobacter pylori strains of human and three of animal origin contain alcohol dehydrogenase (ADH) . Isoelectric focusing of the enzyme showed activity bands with pI at 7.1-7.3, a pattern different from that of gastric mucosal ADHs . The Km value of H . pylori ADH for ethanol oxidation ranges from 64 to 104 mM . Although H . pylori ADH was capable of utilizing both NADP and NAD as cofactors in alcohol oxidation, it showed a strong preference for NADP over NAD . At neutral pH H . pylori ADH was more effective in aldehyde reduction than in alcohol oxidation . Distinct findings suggest that H . pylori ADH could be a metabolic enzyme taking part in ethanol production by fermentation . It is a rather abundant enzyme comprising approx . 0.5% of all bacterial cytosolic proteins . Therefore, the enzyme presumably has a basic role in the functions and maintenance of H . pylori . 4-methylpyrazole inhibits H . pylori ADH, and suppresses its growth during culture . Bismuth compounds that are commonly used in the treatment of H . pylori associated gastric diseases appeared to be potent inhibitors of H . pylori ADH . Owing to its high specific activity for ethanol (14 U mg-1) under physiological conditions H . pylori ADH can also effectively produce acetaldehyde at moderate ethanol levels . This reversed function of the enzyme and the production of the toxic and reactive acetaldehyde could account for at least some of the gastrointestinal morbidity associated with H . pylori infection . H . pylori lacks aldehyde dehydrogenase activity and can therefore not remove acetaldehyde at least by this pathway.

Free Radic Res, 1994 Jan, 20(1), 63 - 8
Free radicals in red wine, but not in white?
Troup GJ, Hutton DR, Hewitt DG, Hunter CR.
By using Electron Spin Resonance (ESR) spectroscopy, we have detected free radicals in red wine, whether fermented on oak or not, and in white wine only when it has been fermented on oak . These radicals would appear to be associated with the phenolics, because the ESR signal from the residue of red wine treated with polyvinyl polypyrrolidone is reduced by approximately 80% . Any inhibition of lipid oxidation by red wine phenolics in vitro will take place in the presence of these radicals, which have a linewidth of 2.0 +/- 0.1 gauss and a g-value of 2.0038 +/- 0.0001.

Appl Biochem Biotechnol, 1994 Spring, 45-46, 569 - 84
Arbinose utilization by xylose-fermenting yeasts and fungi; McMillan JD et al.; Various wild-type yeasts and fungi were screened to evaluate their ability to ferment L-arabinose under oxygen-limited conditions when grown in defined minimal media containing mixtures of L-arabinose, D-xylose, and D-glucose . Although all of the yeasts and some of the fungi consumed arabinose, arabinose was not fermented to ethanol by any of the strains tested . Arabitol was the only major product other than cell mass formed from L-arabinose; yeasts converted arabinose to arabitol at high yield . The inability to ferment L-arabinose appears to be a consequence of inefficient or incomplete assimilation pathways for this pentose sugar.

Appl Biochem Biotechnol, 1994 Spring, 45-46, 383 - 93
Purification and characterization of an acetyl esterase from Aspergillus niger; Linden J et al.; Optimized acetyl esterase enzyme production conditions using Aspergillus niger ATCC 10864 in 14-L fermentation jars were determined to be 33 degrees C, 1.5 vvm aeration, and 300 rpm agitation without pH control . The acetyl esterase was purified by precipitation in 60-80% saturation in ammonium sulfate . The pellet was applied directly to a Pharmacia high-load Phenyl Sepharose column for hydrophobic interaction chromatography and purified to homogeneity in two steps . Stability and kinetic characteristics of the acetyl esterase were determined over a pH range of 4.0-7.5 and from 4 to 45 degrees C . At temperatures > 25 degrees C, stability was superior at pH values < 5.0 . The temperature activity optimum was 35 degrees C, and the pH optimum was 7.0 . The Vmax was determined to be 46,700 U/mg protein, and the Km was 0.023M p-nitrophenyl acetate at pH 6.5 in 0.2M phosphate buffer at 35 degrees C . The mol wt of the enzyme was 35,000 dalton by size-exclusion chromatography and SDS gel electrophoresis . The N-terminal amino acid sequence and the glycosylation composition were also determined.

Appl Biochem Biotechnol, 1994 Spring, 45-46, 367 - 81
Relative rates of sugar utilization by an ethanologenic recombinant Escherichia coli using mixtures of glucose, mannose, and xylose; Lawford HG et al.; The volumetric rates of glucose (G), mannose (M), and xylose (X) utilization by recombinant Escherichia coli B (pLO1297) were compared in pH-stat batch fermentations with Luria broth containing various combinations of two of these sugars at differing mass ratios . Using single substrate media, the rates of glucose, mannose, and xylose utilization were 3.0, 0.8, and 1.5 g/L/h, respectively . With all two substrate media, hexose and pentose sugars were consumed simultaneously . At a mass ratio of 2:1 (M or X:G), the rate of glucose utilization was reduced to 1.7 and 1.2 g/L/h by mannose and xylose, respectively . In media containing glucose and xylose, the rate of xylose utilization was inhibited when the glucose component exceeded about 40% of the total sugar mass in the medium . At a mass ratio of 2M:1X, mannose did not inhibit the rate of xylose utilization . At a mass ratio of 1:2 (G or X:M), the rate of mannose utilization was unaffected by either glucose or xylose . Synthetic media containing a mixture of hexose and pentose sugars were formulated to mimic different biomass hemicellulose hydrolysates . Relative to the rate in a single substrate medium, the respective rates of glucose and xylose utilization were 70% (2.1 g/L/h) and 40% (0.6 g/L/h) in a synthetic softwood prehydrolysate (SW) medium with a total reducing sugar (TRS) content of 45.7 g/L (20 wt% glucose, 30% xylose, and 50% mannose) . However, the rate of mannose utilization in the SW medium was not inhibited . The respective rates of glucose and xylose utilization were 30% (0.9 g/L/h) and > 90% (1.4 g/L/h) in a synthetic crop residue prehydrolysate (CR) medium with a TRS content of 46.9 g/L (10 wt% glucose, 73% xylose, and 17% arabinose) . Based on the results of this study, we suggest that the apparent "preference" for fermentation of hexose sugars by recombinant E . coli may be owing to the decreased rate of xylose transport caused by hexose sugars . Glucose is a more potent modulator of xylose utilization than mannose, but since xylose affects the rate of glucose utilization, this study also points to the importance of the concentration of the different sugars in terms of the relative rates of utilization by recombinant E . coli.

Appl Biochem Biotechnol, 1994 Spring, 45-46, 315 - 27
Production of ethanol from enzymatically hydrolyzed orange peel by the yeast Saccharomyces cerevisiae; Grohmann K et al.; We extended our previous investigations of enzymatic hydrolysis of polysaccharides in orange peel by commercial cellulase and pectinase enzymes to higher, more practical concentrations of orange peel solids . High yields of saccharification could be maintained even at substrate concentrations as high as 22-23%, but the rates of solubilization and saccharification decreased 2-3-fold . We also tested the fermentability of these hydrolysates by the yeast Saccharomyces cerevisiae, which revealed the presence of inhibitory compounds . These compounds could be removed by the filtration of hydrolyzed peel . Successful fermentations of filtered hydrolysates were achieved after pH adjustment with calcium carbonate.

Crit Rev Oral Biol Med, 1994, 5(1), 1 - 25
Composition and cariogenic potential of dental plaque fluid; Margolis HC et al.; Our understanding of the chemical events that take place at the tooth-plaque interface has improved greatly through studies of the chemical composition and properties of dental plaque fluid . In the absence of fermentable carbohydrate, plaque fluid has been found to be supersaturated with respect to tooth mineral and other calcium phosphate phases, thus exhibiting the potential to support calculus formation and the remineralization of incipient carious lesions . Following the exposure to fermentable carbohydrate, the degree of saturation of plaque fluid decreases rapidly, primarily due to lactic acid production and the lowering of plaque fluid pH . The extent of these chemical changes has been shown to be associated with differences in caries history . Such studies have been facilitated by the recent development of microanalytical techniques . Unfortunately, little is known about the relationship between the observed chemical changes in plaque fluid and the microbial composition of plaque . Limited information is also available on the association of immune factors in plaque fluid with dental disease.

Artif Cells Blood Substit Immobil Biotechnol, 1994, 22(3), 641 - 9
Application of aqueous two-phase systems in separation/purification of stroma free hemoglobin from animal blood; Kan P et al.; Aqueous two-phase system (ATPS) is suitable for treatment of biological materials . It has been traditionally employed in the separation of product from fermentation broth, and in the extraction of large-molecule proteins from colloid solution . The separation method based on ATPS features simple, rapid and continuous operation with low equipment cost . A PEG/Salt aqueous two-phase system is studied, and developed for hemoglobin (Hb) separation from animal bloods . Stroma free hemoglobin (SFHb) was extracted from 200ml packed red blood cells by the two-stage aqueous two-phase system and subsequently was desalted and dialyzed by ultrafiltration . It took only 2.5hr to complete overall process to purify SFHb . The purity of SFHb was analyzed by HPLC and IEF (silver staining) . Large partition coefficients of Hb have been observed with proper selection of PEG molecular weight, added concentrations of PEG and salt in each phase . The SFHb of very high purity which is free of other proteins (< 0.1% impurity) and phospholipids (< 2% impurities) may be obtained from human packed RBCs . A two-stage extraction design using ATPS separation concept is very simple and useful for purification of SFHb . The method may be further developed to offer potent technology for hemoglobin separation from animal blood and future production industry of blood substitutes.

Eur J Clin Pharmacol, 1994, 47(1), 33 - 8
Non-lectin component in a fermented extract from Viscum album L . grown on pines induces proliferation of lymphocytes from healthy and allergic individuals in vitro; Stein G et al.; Mistletoe preparations have been shown to express immunomodulatory properties . In order to evaluate the stimulatory potency of different mistletoe extracts, peripheral blood mononuclear cells (PBMC) from healthy and allergic/atopic individuals were exposed to aqueous or fermented extracts derived from Viscum album L . grown on apple trees (Mali-extracts) or on pines (Pini-extracts) . None of them had received any mistletoe treatment . Iscador Pini was the only extract which strongly induced proliferation of PBMC in contrast to the other five preparations . On testing these extracts by Western blotting with anti-mistletoe lectin-1 (ML-1) antibody positive sera from mistletoe-treated patients, it became evident that Iscador Pini was almost devoid of lectins . The stimulatory potency of Iscador Pini for PBMC from three different groups was examined: PBMC from 35 normal controls (Group I), 23 patients with drug-induced adverse effects (Group II) and 16 individuals with allergic manifestations (Group III) . Cells were exposed in 7-day cultures to the extract at concentrations between 1 and 10,000 micrograms/ml . PBMC from 63% of Group III individuals showed strong stimulation (SI varying from 6 to 97) in contrast to only 9% from Group I and 22% from Group II individuals . Anti-ML-1 antibodies were detected in 5% and anti-IP antibodies in 11% of subjects in the three groups . They were either of the IgA or IgM type but not of the IgG type . Our findings strongly imply that a non-lectin associated antigen from Iscador Pini is able to activate PBMC from healthy and allergic/atopic individuals, thereby demonstrating sensitization to probably highly conserved plant antigens.

Arch Microbiol, 1994, 162(3), 199 - 204
Fermentation of phenoxyethanol to phenol and acetate by a homoacetogenic bacterium; Frings J et al.; A strictly anaerobic gram-positive, rod-shaped bacterium, strain LuPhet1, was isolated from sewage sludge with phenoxyethanol as sole carbon and energy source, and was assigned to the genus Acetobacterium . The new isolate fermented the alkylaryl ether compound phenoxyethanol stoichiometrically to phenol and acetate, whereas phenoxyacetic acid was not degraded . In cell-free extracts of strain LuPhet1, cleavage of the ether linkage was shown, and acetaldehyde was detected as reaction product . Coenzyme A-dependent acetaldehyde: acceptor oxidoreductase, phosphate acetyltransferase, acetate kinase, and carbon monoxide dehydrogenase were measured in cell-free extracts of this strain . Our results indicate that the ether linkage of phenoxyethanol is cleaved by a shift of the hydroxyl group to the subterminal carbon atom, analogous to a corrinoid-dependent diol dehydratase reaction, to form an unstable hemiacetal that releases phenol and acetaldehyde . Obviously, phenoxyethanol is degraded by the same strategy as in anaerobic degradation of the alkyl ether polyethylene glycol.

Arch Microbiol, 1994, 162(3), 187 - 92
Pyruvate metabolism in Helicobacter pylori; Mendz GL et al.; The metabolism of pyruvate by Helicobacter pylori was investigated employing one- and two-dimensional 1H and 13C nuclear magnetic resonance spectroscopy . Generation of pyruvate from L-serine in incubations with whole cell lysates indicated the presence of serine dehydratase activity in the bacterium . Pyruvate was formed also in cell suspensions and lysates from phosphoenol pyruvate . Metabolically competent cells incubated aerobically with pyruvate yielded alanine, lactate, acetate, formate, and succinate . The production of alanine and lactate indicated the presence of alanine transaminase and lactate dehydrogenase activities, respectively . Accumulation of acetate and formate as metabolic products provided evidence for the existence of a mixed-acid fermentation pathway in the microorganism . Formation of succinate suggested the incorporation of the pyruvate carbon skeleton into the Kreb's cycle . Addition of pyruvate to various liquid culture media did not affect bacterial growth or loss of viability . The variety of products formed using pyruvate as the sole substrate showed the important role of this metabolite in the energy metabolism of H . pylori.

Biomed Sci Instrum, 1994, 30, 117 - 25
Modeling and optimising lactose fermentation using a fluorosensor; Sundaram S et al.; Lactose has been fermented in a Tokyo Rikakikai Fermentor using two percent seeding at various temperatures . 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 wave length of 360 nm and measurement wavelength of 450 nm . The optimum temperature for this fermentation reaction is 34 degree celsius . At this temperature while biomass growth rate and final biomass concentration are a maximum the time taken to reach the final biomass concentration and lag time are a minimum . The fluorescent voltage vs time data fitted a first order plus dead time model with an error of less than one percent . The present work is in good agreement with earlier work on glucose and lactose fermentation with one percent seeding . The increase in seeding from one to two percent has improved the optimum parameters studied . Further work on higher seeding concentration and higher order models is in progress.

Chirality, 1994, 6(4), 277 - 82
Evaluation of free D-glutamate in processed foods; Rundlett KL et al.; Monosodium glutamate (MSG) is added to many processed foods at significant levels for flavor enhancement . It is also naturally occurring at high levels in some foods . The enantiomeric composition of free glutamate in foods was examined and all foods analyzed were found to contain D-glutamate . The relative percent of D-glutamate in the food products studied depended on the origin of the glutamate . Foods to which MSG was added by the manufacturer had a high total level of MSG but a lower relative percentage of the D-enantiomer (usually less than 0.8%) . In comparison, fermented foods tend to have high relative levels of D-glutamate but a lower total amount of the amino acid . The relative percent of D-glutamate in nonfermented foods containing no added MSG was also found to be low compared to fermented products . In some cases the percent D-glutamate could be related to the relative amounts of other food ingredients such as cheese.

Crit Rev Biotechnol, 1994, 14(4), 311 - 54
The roles of magnesium in biotechnology; Walker GM; This review highlights the important roles played by magnesium in the growth and metabolic functions of microbial and animal cells, and therefore assigns a key role for magnesium ions in biotechnology . The fundamental biochemical and physiological actions of magnesium as a regulatory cation are outlined . Such actions are deemed to be relevant in an applied sense, because Mg2+ availability in cell culture and fermentation media can dramatically influence growth and metabolism of cells . Manipulation of extracellular and intracellular magnesium ions can thus be envisaged as a relatively simplistic, but nevertheless versatile, means of physiological cell engineering . In addition, biological antagonism between calcium and magnesium at the molecular level may have profound consequences for the optimization of biotechnological processes that exploit cells . In fermentation, for example, it is argued that the efficiency of microbial conversion of substrate to product may be improved by altering Mg:Ca concentration ratios in industrial feedstocks in a way that makes more magnesium available to the cells . With particular respect to yeast-based biotechnologies, magnesium availability is seen as being crucially important in governing central pathways of carbohydrate catabolism, especially ethanolic fermentation . It is proposed that such influences of magnesium ions are expressed at the combined levels of key enzyme activation and cell membrane stabilization . The former ensures optimum flow of substrate to ethanol and the latter acts to protect yeasts from physical and chemical stress.

Int J Vitam Nutr Res, 1994, 64(4), 316 - 23
Effects of fructooligosaccharides on the absorption of magnesium and calcium by cecectomized rats; Ohta A et al.; We reported previously that feeding of fructooligosaccharides (FO) increased the apparent absorption of calcium (Ca), magnesium (Mg) and phosphorus (P) in rats . We suggested that there was an important correlation between this phenomenon and fermentation of FO in the large intestine . However, the precise mechanism remained to be characterized . Therefore, we performed a mineral-balance study to identify the segment of lumen in which FO affects mineral absorption, using cecectomized rats . Sham-operated rats and cecectomized rats were fed a control diet (without FO) or an FO-diet (containing 50 g of FO per kg of feed) for 28 days . Feeding of the FO-diet decreased the luminal pH in the cecum and colon in the sham-operated rats . In the cecectomized rats, feeding of the FO-diet also decreased the luminal pH in the colon . Thus, FO was fermented in the colon of the cecectomized rats . However, the acid composition of feces was altered by cecectomy . Feeding of the FO-diet increased the absorption of Ca and Mg in the sham-operated rats . In the cecectomized rats, the FO-diet increased the absorption of Mg but did not increase the absorption of Ca . These results suggest the mechanisms for the absorption of Ca and Mg when rats are fed an FO are different.

Dev Biol Stand, 1994, 83, 93 - 7
Genetic stability of rDNA production systems, a case report; Chiu YY; Producing rDNA proteins to be used as human therapeutic agents requires a biological production system during both storage and growth . The genetic make-up of a biological system is usually known through the laboratory history of the host strain and the process of vector construction . All master cell banks prepared for the production of medicinal products are fully characterized at the genetic and biochemical level . Whether these characteristics can be consistently maintained, particularly when the cells are propagated through a high number of generations and the culture grown into tens of thousands of litres, will have significant effects on the quality of the final products . Considerable experience and data regarding the stability of biological production systems involving plasmid and E . coli or yeast have been accumulated during the past 10 years . These data, including size and restriction analyses of the plasmid and sequence determination of relevant portions of the plasmid DNA isolated from cells collected before culture harvest, demonstrated that plasmid alteration at the structural level do occur, and some with high frequency or concentration . Assisted by such genetic information, criteria for accepting or rejecting a fermentation run can be established.

Dev Biol Stand, 1994, 83, 45 - 54
Consistency and stability of recombinant fermentations; Wiebe ME et al.; Production of proteins of consistent quality in heterologous, genetically-engineered expression systems is dependent upon identifying the manufacturing process parameters which have an impact on product structure, function, or purity, validating acceptable ranges for these variables, and performing the manufacturing process as specified . One of the factors which may affect product consistency is genetic instability of the primary product sequence, as well as instability of genes which code for proteins responsible for post-translational modification of the product . Approaches have been developed for mammalian expression systems to assure that product quality is not changing through mechanisms of genetic instability . Sensitive protein analytical methods, particularly peptide mapping, are used to evaluate product structure directly, and are more sensitive in detecting genetic instability than is direct genetic analysis by nucleotide sequencing of the recombinant gene or mRNA . These methods are being employed to demonstrate that the manufacturing process consistently yields a product of defined structure from cells cultured through the range of cell ages used in the manufacturing process and well beyond the maximum cell age defined for the process . The combination of well designed validation studies which demonstrate consistent product quality as a function of cell age, and rigorous quality control of every product lot by sensitive protein analytical methods provide the necessary assurance that product structure is not being altered through mechanisms of mutation and selection.

Dev Biol Stand, 1994, 83, 21 - 6
Translational errors during recombinant protein synthesis; Rosenberger RF; Cloned human genes can now be readily expressed in organisms like Escherichia coli (E . coli) and fungi and this has made recombinant human proteins available for use in clinical medicine . Expressing foreign proteins at high rates to make them major cell components can, however, lead to nutritional stresses in the production cells . Such stresses markedly increase the frequency of random translational errors, both in model laboratory experiments and in actual fermentations . The burden of detecting and removing errors then falls on the purification processes . Random errors are, however, difficult to detect as they will produce a heterogeneous mixture of polypeptides . Each type of altered protein may be present in quite small amounts but the total number of erroneous molecules could be substantial . Little is known about how erroneous proteins could affect patients and much more information is needed to clarify this problem . Techniques for limiting and monitoring translational errors are briefly discussed.

Dev Biol Stand, 1994, 83, 135 - 42
Analytical strategies for the determination of protein modifications; Janis LJ et al.; Assessment of recombinant protein product purity and consistency has been successfully accomplished by using a battery of quantitative analytical methods . The development of analytical methods for product control requires an understanding of potential changes in protein structure which could be caused by degradation and modification . This paper will review some of the common mechanisms of protein degradation and common modifications which can occur during the fermentation/cell culture and purification processes . It will also present examples of analytical techniques which have successfully elucidated some of these changes in protein structure.

Dev Biol Stand, 1994, 83, 13 - 9
Genetic stability of protein expression systems in yeast; Bussineau CM et al.; For the expression of recombinant proteins in yeast, genetic stability is monitored using a combination of standard microbiology and nucleic acid testing procedures . Process consistency during the cell amplification and product expression phases of fermentation are also reliable indicators of stability . The potential for instability arising from point mutation, gene conversion or recombination has been shown to occur at a low frequency and does not generally affect protein product quality.

Trop Geogr Med, 1994, 46(5), 309 - 12
Infant-feeding practices in urban and rural communities of the Sudan; el Bushra HM et al.; Infant-feeding and weaning practices were investigated in a multistage randomly selected sample of 1,039 Sudanese mothers who represented six of the nine States of the Sudan . The majority (77.9%) believed that breast milk was best for their babies, emphasizing the previously reported high breast-feeding rate in Sudanese mothers . Food supplementation started by 6 months in 82.5% mainly in urban middle and high classes (UMC and UHC) compared to urban poor class (UPC) and the rural group (RG; p < 0.001) . A mixture of food items was used for supplementation by 62.1% of the study group, whereas giving one food item was significantly more practised in RG (54.9%) compared to others (p < 0.001) . Household food was introduced by 6 months in 35.4% . Weaning started between 6 and 12 months in 27.1% and thereafter in 64.9% . A greater proportion of rural mothers (36.5%) weaned their babies after the age of 18 months (p < 0.001) . About half the children (52.8%) were weaned abruptly, mainly among UPC and RG . The first food item of choice for weaning was fresh goat's or cow's milk (77.6%), followed by powdered or formula milk (16.1%) . The commonest second preferred food was a starch gruel (39.1%) made either of rice (24.5%) or fermented sorghumPIP: In six of the nine states of the Sudan, a random multistage cluster sampling technique was used to select 1039 mothers in the towns of Shandi, Port Sudan, El Fashir, Kosti, El Hasahisa, Omdurman, the village of Ellirri, and villages near Shandi, Sinkat, and Abu Hamad . Medical students from the selected areas interviewed the mothers . The study aimed to examine infant feeding and weaning practices . 77.4% of the mothers considered breast milk to be best for their baby, reflecting the high breast feeding rate (92% at 6 months) reported previously . The foods identified as second-best were local cereals (e.g., fermented sorghum gruel) (36.9%), fresh goat's or cow's milk (22.5%), bananas and oranges (11.3%), and formula milk (7.7%) . Only 1% of newborns received food supplements . 82.5% of mothers supplemented breast milk with other foods by age 6 months . The urban high and middle classes were more likely to practice food supplementation at 6 months than the urban poor and the rural groups (90.3% and 89.7% vs . 79.3% and 74.1%, respectively; p 0.001) . 62.1% of all mothers supplemented breast milk with a mixture of foods . Rural mothers were more likely to supplement with only one food item than urban mothers (54.9% vs . 28.3-30.6%; p 0.001) . 35.4% and 90.7% of mothers introduced household foods at 6 and 9 months, respectively . 27.1% of mothers began weaning between 6 and 12 months . 64.9% of mothers began weaning after 12 months . A significant percentage of rural mothers (36.5%) began weaning after 18 months (p 0.001) . 52.8% of mothers weaned their children abruptly, especially rural women and the urban poor . The most preferred first weaning foods were fresh milk (77.6%) and powdered or formula milk (16.1%) . The most preferred second weaning foods were starch gruel made of fermented sorghum or rice (39.1%) and powdered or formula milk (19.1%) .

Antonie Van Leeuwenhoek, 1994, 65(4), 369 - 80
Solute transport and energy transduction in bacteria; Konings WN et al.; In bacteria two forms of metabolic energy are usually present, i.e . ATP and transmembrane ion-gradients, that can be used to drive the various endergonic reactions associated with cellular growth . ATP can be formed directly in substrate level phosphorylation reactions whereas primary transport processes can generate the ion-gradients across the cytoplasmic membrane . The two forms of metabolic energy can be interconverted by the action of ion-translocating ATPases . For fermentative organisms it has long been thought that ion-gradients could only be generated at the expense of ATP hydrolysis by the F0F1-ATPase . In the present article, an overview is given of the various secondary transport processes that form ion-gradients at the expense of precursor (substrate) and/or end-product concentration gradients . The metabolic energy formed by these chemiosmotic circuits contributes to the 'energy status' of the bacterial cell which is particularly important for anaerobic/fermentative organisms.

Annu Rev Microbiol, 1994, 48, 687 - 712
AIDS-associated mycoplasmas; Blanchard A et al.; Previously, we hypothesized that mycoplasmas could act as cofactors accelerating the progression of HIV disease . In the present paper, we review the current knowledge on three mycoplasmas (Mycoplasma fermentans, M . penetrans, and M . pirum) that have been implicated as these putative cofactors . All three mycoplasmas have been isolated from patients with HIV infection, and serological studies have suggested that the presence of M . penetrans could be associated with HIV infection . These mycoplasmas share the capacity to hydrolyze arginine and ferment glucose as well as to attach to and invade eukaryotic cells . The possible mechanisms that could allow mycoplasmas to influence HIV pathogenesis, specifically through the activation of the immune system or the production of superantigen or by contributing to the oxidative stress observed in HIV-infected subjects, are discussed . These studies have offered and will continue to offer major contributions to a better understanding of mycoplasmal flora in humans and have begun to unveil some of the mechanisms of virulence of these organisms.

Vopr Pitan, 1994, (4), 43 - 4
{Improved device and method for determination of protein digestibility in vitro}; Lipatov NN et al.; The ten-cells device for modelling of ferment hydrolysis of food proteins by acid basic proteases of human alimentary canal is described . The new procedure for the calculation of quantitative characteristic of proteins digestion "in vitro" is presented.

J Basic Microbiol, 1994, 34(6), 379 - 85
Osmotolerant yeasts isolated from Tokaj wines; Miklos I et al.; Yeasts growing in "Tokaj Aszu" wine and in "Aszu essence" were isolated and characterised . They proved to be physiological races of Saccharomyces cerevisiae and showed high osmotolerance, which was an inherited feature rather than the result of adaptation . No correlations were found between the osmotolerance and the ethanol tolerance or the cell size and morphology . Yeasts in "Aszu essence" are usually undesirable contaminants that impair the quality of the essence . The isolate characterized in this work exhibited physiological parameters very similar to those of the "Tokaj Aszu" strain, which make it a potent competitor of other yeasts in Aszu fermentation . However, the high termo sensitivity of its cells offers a possibility to eliminate them selectively.

Crit Rev Food Sci Nutr, 1994, 34(5-6), 499 - 511
Whole grains--impact of consuming whole grains on physiological effects of dietary fiber and starch; Stephen AM; Much of the present research on the physiological effects of dietary fiber and starch has been done on sources isolated from the parent material, and it is not clear whether they have the same effects if fed in the intact or whole grain . For dietary fiber, physiological effect depends on extent of fermentation in the large intestine, and this is influenced by chemical composition, solubility, physical form, and presence of lignin or other compounds . All of these factors are altered by isolation of a fiber source from the whole grain, and hence effects of eating fiber vary . Similarly, physical form and presence in the whole grain will affect digestibility of starch in the small intestine, which in turn influences the glycemic response and colonic effects determined by the extent of malabsorption and entry into the colon . Starch that enters the colon is fermented and produces short-chain fatty acids, particularly butyrate, which is necessary to maintain a healthy mucosa . Hence, their presence within the whole grain may have important implications for health for both dietary fiber and starch . Evidence indicates that such effects are beneficial and that whole-grain consumption should be encouraged.

Chin J Biotechnol, 1994, 10(2), 83 - 9
The glutamate biosensor and its application to flow injection analysis system; Ye B et al.; A micro-enzyme electrode was fabricated by cross-linking L-glutamate oxidase with glutaraldehyde on aminopropyl-platinized platinum wire . A flow injection analysis system with glutamate sensor was used for L-glutamate determination . The peak current is linearly related to the L-glutamate concentration in the range of 0.02-2.0 mM, with good performance, accuracy (CV = 0.4%), fast response (< 60s), and stability (> 20 days) . The system was applied to determine the concentration of L-glutamate in a fermentation broth . The recovery rate was in the range of 98.7-107.5%.

Chin J Biotechnol, 1994, 10(2), 113 - 9
Studies on high concentration ethanol fermentation of raw ground corn by Saccharomyces sp . H0; Chi Z et al.; In this study, high concentration alcoholic fermentation coordinated with saccharification from raw ground corn was performed at 30 degrees C, pH 4-5, in batch culture using Saccharomyces sp . H0 which was constructed by hybridization in this laboratory and the glucoamylase preparation produced on a large scale in China . The optimal conditions for high concentration ethanol production were that the amount of the glucoamylase preparation was 300 u/g of raw ground corn, the inoculum size of the yeast was 2.7 x 10(6) cells/ml, the fermentation temperature was 30 degrees C, the starting concentration of raw ground corn was 33.0% (w/v), and the fermentation period was 70 hr . At the end of fermentation, 17.5% (v/v) ethanol was yielded, with 0.19% reducing sugar, 3.5% total sugar and 16.0% cell viability remaining in the fermented mash . In the case of 36.0% (w/v) of the initial raw ground corn concentration, the strain could produce 18.0% (v/v) ethanol, leaving 0.81% reducing sugar and 5.1% total sugar in the media . We found that the glucoamylase preparation which is usually employed for saccharification of cooked starch could be used for efficient saccharification of raw ground corn starch.

Chin J Biotechnol, 1994, 10(2), 105 - 12
The optimization of technological condition in the fermentation process of glutamate by pattern recognition method; Xu C et al.; The technological condition in the fermentation process of fermentation glutamate (such as pH value, temperature, ventilation rate, etc.) were optimized by computerized pattern recognition method . The visible optimum region may be found based on the mapping from the multi-dimensional pattern space into a plane . It is then transformed along the reciprocal direction into the original data space using Monte Carlo simulation, so the orientation of optimization and the best combination of all parameters can be determined . A new mathematical model is being proposed based on the experimental evidence in production . The transfer ratio of glucose to glutamic acid, the production capacity and the glutamic acid concentration increase 2.9%, 1.45% and 2.65% respectively by operating this optimization method . The method has been widely extended to factories and has granted in decreasing the expense of raw materials and that of the production cost.

Rocz Panstw Zakl Hig, 1994, 45(4), 301 - 9
{The influence of potassium sorbate addition on the quality of pickled zucchini fruit}; Kmiecik W et al.; The investigation included zucchini cultivars of Polish (Astra) and foreign (Storr's Green F1) breeding . The analysed material was harvested in the investigator's experimental field . Lactic fermentation at controlled temperature of fruits 100-130 mm in length was carried out in early September, the variants consisting of souring at the concentration of 0.05% and 0.10% in the brine which filled 35% of the volume of pickling containers . The evaluation of pickles was carried out after 6 month of souring . The raw material for pickling contained 8.67-9.66% of dry matter, 2.47-2.60% of sugars, 1.84-18.9% protein (N x 6.25), 0.42-0.50% of pectic compounds, and 46.9 mg/100 g of vitamin C . The pickles were characterized by a good organoleptic quality expressed by scores from 4.39-4.96 and by the following physico-chemical composition: dry matter 8.11-8.86%, sugars 0.9-0.11%, N x 6.25 1.54-1.56%, total acidity 0.82-1.01%, sodium chloride 2.15-2.26%, pectic compounds 0.20-0.25%, volatile acidity 43-64 mg/100, ethyl alcohol 30-35 mg/100 g, and vitamin C 10.9-14.9 mg/100 g . The addition of potassium sorbinate to the brine favourably affected the chemical composition and organoleptic quality of the final product . With the level of sorbic acid in pickles rising from 0 to 26 mg/100 g (the 0.10% addition of potassium sorbinate to the brine) the total content of acids increased by 18% and the content of preserved vitamin C by 32%, while the amount of volatile acids was reduced by 25% and that of ethyl alcohol by 38%.(ABSTRACT TRUNCATED AT 250 WORDS)

Chin J Biotechnol, 1994, 10(4), 291 - 7
Determination of L-glutamate using flow injection analysis with immobilized L-glutamate oxidase reactor; Li Q et al.; L-Glutamate oxidase (GOD) and horseradish peroxidase (HRP) were covalently coupled on alkylamine pretreated controlled pore glass (CPG) by means of glutaraldehyde . The immobilized enzymes were packed into a teflon tube and used in flow injection analysis (FIA) system for L-glutamate determination . A good linearity range was obtained at 0.1-2.0 mM, and the coefficient of variation was 0.7% (n = 8) . More than 80 samples were measured within an hour . The stability of the immobilized GOD reactor was good, retaining 50% of its initial activity after 4 months storage in buffer at 4 degrees C . When the concentration of L-glutamate remained lower than 2.5 mM, the determination of L-glutamate in this system was not affected by pH and temperature within the range of 6.0-8.0 and 20-35 degrees C, respectively . The system was applied to determine L-glutamate in broth samples during L-glutamate fermentation and good correlations were achieved between results obtained with the FIA system, L-glutamate oxidase kit and Warburg's method.

Chin J Biotechnol, 1994, 10(4), 283 - 90
Studies on the condition of fermentation of pullulan by Aureobasidium pullulans; Sun W et al.; Studies on optimal conditions for pullulan fermentation based on the results obtained from a shaking flask were carried out in a 16-L auto-controlling fermentor . It found that the optimal DE value of starch hydrolyzate was 40-50 when 10% starch hydrolysate was used as carbon source . The optimal concentration of ammonium sulfate in the medium for fermentation was different from that of the shaking flask . The fermentation kinetics and effects of seed age, seed volume, airflow rate, pressure of tank, agitation speed and number of vane group on the production of pullulan were investigated.

Chin J Biotechnol, 1994, 10(4), 271 - 82
Pseudohomogeneous kinetic study on a two-liquid-phase fermentation process; Li Y et al.; The fermentation process for producing undecane dicarboxylic acid from tridecane, which includes gas-oil-water-cell four phases (two-liquid-phase), was studied . The metabolic characters of the cell growth phase and the production phase of the process were analyzed . It was proposed that cell growth can be identified by the carbon dioxide production rate (CPR) before the production phase . The kinetic models of both the cell growth phase and the production phase were established, respectively . The parameters of the models have been estimated by regression . The calculated curves fit the experimental data very well . The average deviation between those over the cell growth phase and the production phase are 2.4% and 3.6%, respectively.

Chin J Biotechnol, 1994, 10(4), 257 - 64
Human alpha atrial natriuretic peptide fermentation by using a genetically engineered yeast strain; Ye Q et al.; The genotype of the recombinant yeast strain Y33::YFD71-3 used in this study is alpha, his, leu, ade and suc . Preliminary batch cultures in shaking flasks showed the expression level of atrial natriuretic peptide (ANP) was 1-2 mg/L . Shaking flask cultures were carried out in YG medium which contained glucose, yeast nitrogen base (YNB), and different amounts of adenine, histidine and leucine . When the growth was limited by adenine, protein secreted from Y33::YFD71-3 cells was increased obviously . Adenine became the limiting substrate when the YG medium was supplemented with 5 g/L of casamino acid (CAA) and the level of ANP expression was influenced by the concentrations of adenine, YNB and leucine in the medium . In fed batch cultures carried out in a RIBE-5 fermenter, the cultures were fed with glucose and a mixture of YNB, CAA, adenine, histidine and leucine to improve cell growth and ANP expression, and the maximum ANP concentration in the culture reached 24.8 mg/L.

Rocz Panstw Zakl Hig, 1994, 45(3), 167 - 80
{The content of nitrates and nitrites in fruits, vegetables and other foodstuffs}; Nabrzyski M et al.; There are presented the results of the investigation of many popular fresh and frozen vegetables as well as in fresh and frozen fruits, such as different kind of apples, strawberries, currants, raspberries and many other tender fruits mainly from market and few from own allotment-cottages performed in the year 1989-1992 . The nitrate and nitrite was determined according to the Griess reaction . High levels of nitrate was encountered in lettuce, frozen spinach, fennel, radishes, parsley . Many of this samples contained more than 1000 mg of KNO3/kg of fresh product, but the highest level, over the 3500 mg/kg was found in lettuce . The remaining vegetables like carrots, celery, leeks and frozen French bean contained from several dozen to more than 800 mg KNO3/kg . The level of nitrite in all samples of the investigated vegetables and fruits was very low from zero to decimal part of milligram per kg . Very low level of nitrate was found in 7 species of investigated apples (from 1.3 to 9.7 mg KNO3/kg) . A little higher level of this compound was ascertained in currants, gooseberries, raspberries, cherries (from 0.0 to 36.0 mg KNO3/kg product) . The highest levels of nitrate occurred in samples of strawberries (maximum to 322.3 mg KNO3/kg) but mean level amounted 58.7 mg KNO3/kg . The encountered levels of nitrate in frozen vegetables and fruits as well as in jams and stewed fruits was only little less than in fresh products . Very high level (from 355.30 to 584.53 mg KNO3/kg) was ascertained in the fruit-vegetable juice named "Rinberen" and "Malberen" to which red beet extract was used for their production . It should be pointed out that when the containers of these juice was opened and stored at the room temperature (+20 degrees C) during 30 days, no changes was observed in the level of nitrate and nitrite . In the juice prepared from blanched carrot, the rate of the reduction of nitrate to nitrite has not been lowered, when this product was storage of this juice at room temperature, the mean level of nitrite increased significantly (from 0.14 to 82.89 mg NaNO2/kg) and the level of nitrate lowered from 261.0 to 46.4 mg KNO3/kg . It should be strongly recommended for consumption the juices from carrot only fresh prepared . There are also presented the results of investigation of nitrate in fermented cheeses.(ABSTRACT TRUNCATED AT 400 WORDS)

Invest New Drugs, 1994, 12(4), 315 - 7
Phase II study of elsamitrucin in non-small cell lung cancer; Goss G et al.; Elsamitrucin (BMY-28090) a novel fermentation product has demonstrated pre-clinical anti-tumour activity against a number of cell lines . The dose limiting toxicity in phase I studies was a reversible increase in hepatic transaminase . This study was initiated to determine the activity of elsamitrucin in patients with previously untreated, bi-dimensionally measurable, cytologically or histologically proven, non-small cell lung cancer who were not curable by surgery . Elsamitrucin at a dose of 25 mg/m2 was administered intravenously over 5-10 min weekly for a minimum of 6 weeks . Seventeen patients were entered on study, 15 were evaluable for toxicity and 14 evaluable for response . No responses were documented in the 14 patients evaluable for response . Both hematological and non-hematological toxicities were mild to moderate in severity . The commonest being nausea, vomiting, lethargy and local skin reactions at the site of the infusion . These results indicate that elsamitrucin when given in this dose and schedule to patients with surgically incurable non-small cell lung cancer has no activity.

Cytotechnology, 1994, 15(1-3), 243 - 51
Evaluation of membranes for use in on-line cell separation during mammalian cell perfusion processes; Buntemeyer H et al.; In this study two microporous hollow fibre membranes were evaluated for their use as cell retention device in continuous perfusion systems . A chemically modified permanent hydrophillic PTFE membrane and a hydrophilized PP membrane were tested . To investigate the filtration characteristic under process conditions each membrane was tested during a long term perfusion cultivation of a hybridoma cell line . In both cultivations the conditions influencing membrane filtration (e.g . transmembrane flux) were kept constant . Filtration behaviour was investigated by monitoring transmembrane pressure and protein permeability . Transmembrane pressure was measured on-line with an autoclavable piezo-resistive pressure sensor . Protein permeability was determined by quantitative evaluation of unreduced, Coomassie stained SDS-PAGE . The membrane fouling process influences the filtration characteristic of both membranes in a different way . After fermentation the PP membrane was blocked by a thick gel layer located in the big outer pores of the asymmetric membrane structure . The hydraulic resistance was higher but the protein permeability was slightly better than of the PTFE membrane . For this reason the PP membrane should be preferred . On the other hand, transmembrane pressure decreases slower when the PTFE membrane is used, which favours this membrane for long term cultivations, especially when low molecular weight proteins (< 30 KD) are produced.

Cytotechnology, 1994, 15(1-3), 169 - 76
Optimization of vaccine production for animal health; Noe W et al.; Vaccines on the basis of mammalian cell cultures are of major importance for human and animal health . Therefore efforts are undertaken for the improved production of more effective vaccines . Of course, the main purpose of all these approaches is to save lives and improve the quality of life for human beings . However, there is also some remarkable effort in the food industry and the associated animal production, especially in the case of some Flaviviridal viruses (BVD), where > 80% of all cattle herds are found to be infected . These viruses can cause tremendous economic losses of calfs and embryos (Ames, 1990) . Because of these facts, there is a continuous endeavour for improving the manufacturing of therapeutics or preventing agents such as vaccines for the treatment of cattle . The competitive economic situation and the specific market demands still require effective and high yield production methods, especially in the case of one of the most widespread viral diseases in cattle like BVD (Ames, 1990) . We have succeeded in establishing an improved method for the production of BVD on the basis of a continuous fermentation mode, that consist of modifications of the corresponding process and media improvements.

Cytotechnology, 1994, 16(2), 79 - 87
Production of mouse monoclonal antibodies using a continuous cell culture fermenter and protein G affinity chromatography; Zamboni A et al.; The production of anti-alpha-fetoprotein monoclonal antibodies for diagnostic use was carried out in a stirred tank fermenter equipped with a double membrane stirrer for bubble free aeration and continuous medium perfusion . A serum-free medium supplemented with 4 mM L-glutamine and 2.0 milligrams glucose with a protein content of only 780 micrograms/ml was used for the production process . The harvested antibodies were concentrated 50-fold using a tangential ultrafiltration system and were then purified in a one step purification process by protein G affinity chromatography . The purity of the final product (90%) was controlled by SDS-polyacrylamide gel electrophoresis, gel exclusion chromatography and isoelectric focussing . For further quality controls of the product the immunoglobulin subclass and the isoelectric point were determined and the specificity of the purified mAb was tested by RIA using 125I labelled alpha-fetoprotein . 1.87 g of purified monoclonal antibodies were produced (90% purity) within 2 weeks . It was found that the use of this type of stirred tank fermenter combined with a one step purification process using protein G affinity chromatography represents a suitable method for the fast production of medium scale quantities (500 mg-5 g) of monoclonal antibodies for diagnostic use.

Cytotechnology, 1994, 16(2), 67 - 77
Detection of mycoplasma contaminations by the polymerase chain reaction; Wirth M et al.; The polymerase chain reaction (PCR) has been used for the general detection of Mollicutes . 25 Mycoplasma and Acholeplasma species were detected including important contaminants of cell cultures such as M . orale, M . arginini, M . hyorhinis, M . fermentans, A . laidlawii and additional human and animal mycoplasmas . PCR reactions were performed using a set of nested primers defined from conserved regions of the 16S rRNA gene . The detection limit was determined to be 1 fg mycoplasma DNA, which is equivalent to 1-2 genome copies of the 16S rRNA coding region . The identity of the amplification products was confirmed by agarose gel electrophoresis and restriction enzyme analysis . DNA from closely and distantly related micro-organisms did not give rise to specific amplification products . The method presented here offers a much more sensitive, specific and rapid assay for the detection of mycoplasmas than the existing ones.

Cytotechnology, 1994, 14(2), 129 - 46
Change in growth kinetics of hybridoma cells entrapped in collagen gel affected by alkaline supply; Shirai Y et al.; The growth yields for glucose and glutamine of murine hybridoma cells entrapped in collagen gel particles were examined during the growth phase . The immobilized hybridoma cells were cultivated in a fluidized bed fermenter where the medium was circulating to supply oxygen separately . Procedures to supply an alkaline solution for adjusting the pH level strongly affected the growth yields . A direct supply of the alkaline solution to the cultivation system reduced both the growth yields for glucose and glutamine, probably due to a local increase in pH level . On the other hand, when fresh medium in which the pH was adjusted to around 8.5 was added to the cultivation system, the growth yields were unchanged even at the same pH level as when direct alkaline supply was used . These results suggest that an indirect alkaline supply could be recommended to adjust the pH level when using medium-circulating-fermenters.

Biotechnol Prog, 1994 Jan-Feb, 10(1), 125 - 8
Enhanced productivity through gratuitous induction in recombinant yeast fermentations; Napp SJ et al.; The advantages of gratuitous induction for GAL-regulated cloned gene (lacZ) product synthesis were evaluated for the yeast Saccharomyces cerevisiae . The growth, yield, and productivity of a gratuitous (gal1) strain were compared with those of an otherwise isogenic, nongratuitous (GAL1) strain . Batch studies clearly demonstrated the improvements possible in product synthesis when the inducer is not metabolized by the yeast cells; both beta-galactosidase specific and volumetric activities were superior for the gal1 strain . At equivalent metabolizable sugar concentrations, the productivity of the gratuitous strain exceeded that of the nongratuitous strain by 180% . The effects of initial inducer concentration and induction time were also examined . For the gratuitous strain, galactose:glucose ratios as low as 0.1 still gave maximum beta-galactosidase volumetric activity . A 5-fold higher ratio was necessary for full induction with the nongratuitous strain, and productivity was substantially lower relative to the gal1 strain . A comparison of various times for galactose addition indicated that productivity is highest when the gratuitous culture is induced for the entire batch fermentation.

Arch Tierernahr, 1994, 46(1), 37 - 50
A comparative study of nutrient digestibility, kinetics of digestion and passage and rumen fermentation pattern in goats and sheep offered medium quality forages at the maintenance level of feeding; Isac MD et al.; The in vivo digestibility and the rates of degradation and passage of alfalfa hay (AH) and vetch straw (VS) were compared in three Granadina goats and three Segurena wethers fed at approximately maintenance level, using a change over design . The nylon bag technique was used to estimate the fractional rate of degradation of the feeds in the rumen . The fractional outflow rate of hay and straw particles was determined with chromium as a marker . No significant differences in the digestibility coefficients of nutrients between animal species were found . Nitrogen retention expressed as coefficients of both nitrogen intake and digested nitrogen was lower (P < 0.01) in goats than in sheep when VS was offered . There was no significant difference between goats and sheep in the effective degradability (measured at outflow rates in the range of 0.027 to 0.032 h-1) of dry matter (DM) for either forage . However, the effective degradabilities of the neutral detergent fibre (NDF) and crude protein (CP) of VS were lower (P < 0.01 and P < 0.001, respectively), in goats than in sheep . The degradation rates of DM, NDF and CP were not significantly different (P > 0.05) between goats and sheep . Also, the fractional rate of passage of particles from the rumen was not different (P = 0.056) between species, although there was a tendency for an increased outflow rate in goats . In a second experiment the effects of animal species, type of diet and frequency of feeding on rumen fermentation pattern were studied following a factorial design . Four goats and four wethers were used . They were randomly allocated to three dietary treatments: AH, VS or a 50:50 mixture of AH and VS (AH/VS) . Rations were offered in two or three meals daily and samples of rumen content were obtained at 09.00, 11.00, 13.00, 15.00, 17.00 and 19.00 h . No difference in rumen pH was found between goats and sheep . Total volatile fatty acids and ammonia concentrations were higher (P < 0.001) in sheep than in goats . The molar proportions of acetate and isovalerate were higher (P < 0.01 and P < 0.001, respectively) in goats than in sheep, whereas the opposite was true for the molar proportion of n-butyrate . Feeding frequency had a slight effect on the rumen parameters measured . It is concluded that only minor differences in the digestive capacity and rumen activity of sheep and goats can be expected when they are fed on medium quality forages.

Nat Toxins, 1994, 2(6), 354 - 9
Production and purification of fumonisins from a stirred jar fermenter; Miller JD et al.; The production, isolation and purification of fumonisins from 10 litre liquid cultures are described . Measurements of sucrose, fructose and glucose consumption, oxygen demand, dry weight increase, CO2, and fumonisin production were taken every 48 hours . The specific productivity of fumonisins was found to be similar to that reported for corn cultures but purification was much simpler, yielding an 89% recovery . The method developed for the purification of fumonisins from liquid culture was also applied to a corn culture, resulting in a 70.1% recovery.

Arch Tierernahr, 1994, 47(1), 75 - 87
Comparative studies on the efficiency of various biological silage additives for the ensiling of lucerne; Keller T et al.; Enzyme preparations, inoculants, molasses, sodium formate, urea as well as combinations thereof were tested for their efficiency in the ensiling of lucerne (Medicago varia) . The experiments were carried out both on fresh plant material (180 g dry matter (DM)/kg) and wilted material obtained after graded times of wilting (28, 52 and 76 hours) . Dry matter contents varied between 360 and 710 g/kg . Differentiated dry matter contents of this order are normal when lucerne is ensiled in plastic-wrapped big bales with varying periods of exposure in the field depending on the operational performance . The experiments were launched to test a large number of biological silage additives for their suitability as quality promoters in this conservation technique . Depending on dry matter content the additives were expected to produce differentiated results . On lower DM level especially molasses addition, also together with inoculants, improved fermentation . From about 500 gDM/kg upwards progressive mould development was observed, which was avoided reliably only by adding urea.

Arch Tierernahr, 1994, 46(3), 217 - 36
{Use of free fatty acids in animal nutrition}; Bergner H et al.; The description of the processes of absorption of free fatty acids in monogastric animals and in ruminants is the first part of the review . The feeding problems of free fatty acids are discussed in the second part . In pig diets is a level up 6% free fatty acids in the dry matter of the ration not disadvantageous . In the feeding of ruminants additionally free fatty acids reduce the fermentation processes in the rumen . Only protected free fatty acids (Ca-fatty acids) are favourable in feeding systems for high yielding cows.

Klin Khir, 1994, (10), 29 - 31
{Use of glycerin as a component of the solution in treating acute hemorrhage}; Gavriliuk VA et al.; The multicomponent solution, containing 15% of glycerol, 4.5% of proteins, 0.9% of sodium chloride, 0.33% of potassium chloride and water for injections, was proposed . The ferments activity (aminotransferases, cholinesterase, aldolase, alkaline phosphatase), blood coagulating system state (the prothrombin level, plasma tolerance, her recalcification time), the mineral elements contents (potassium, sodium, calcium), the contents of protein and its fractions in blood before and after an acute blood loss compensation with the multicomponent solution, and also its influence on the animals organism in prolonged daily (during 30 days) intravenous injection were studied . The combination of components in the solution permit to store the studying indexes on level close to initial; if the loss of blood compensates in the first hours, high survival of animals is insured . Negative reactions of organism while prolonged intravenous injection of the multicomponent solution are not revealed.

Cytotechnology, 1994, 15(1-3), 139 - 44
Recombinant protein expression in a Drosophila cell line: comparison with the baculovirus system; Bernard AR et al.; In this report, we compare two different expression systems: baculovirus/Sf9 and stable recombinant Drosophila Schneider 2 (S2) cell lines . The construction of a recombinant S2 cell line is simple and quick, and in batch fermentations the cells have a doubling time of 20 hours until reaching a plateau density of 20 million cells/ml . Protein expression is driven by the Drosophila Metallothionein promoter which is tightly regulated . When expressed in S2 cells, the extracellular domain of human VCAM, an adhesion molecule, is indistinguishable from the same protein produced by baculovirus-infected Sf9 cells . Additionally, we present data on the expression of a seven trans-membrane protein, the dopamine D4 receptor, which has been successfully expressed in both systems . The receptor integrates correctly in the S2 membrane, binds {3H}spiperone with high affinity and exhibits pharmacological characteristics identical to that of the receptor expressed in Sf9 and mammalian cells . The general implications for large scale production of recombinant proteins are discussed.

Acta Microbiol Pol, 1994, 43(1), 47 - 56
Comparison of utilization of pectins from various sources by pure cultures of pectinolytic rumen bacteria and mixed cultures of rumen microorganisms; Kasperowicz A; Utilization of citrus, lucerne, apple and sugar beet pulp pectins by pure strains of rumen bacteria, Prevotella ruminicola, Lachnospira multiparus and Butyrivibrio fibrisolvens was compared . Additionally, the utilization of pectins by mixed rumen microorganisms was evaluated . The comparison was based on the depletion of galacturonic acid from medium, content of cellular protein in the cultures and the amount of end products of pectin fermentation in cell-free culture fluids . It was found that citrus pectin was utilized best; utilization of lucerne, apple and sugar beet pectins was dependent on the species of bacteria . P . ruminicola and B . fibrisolvens utilized polygalacturonic acid from sugar beet pectins better than that from apple or lucerne pectin, while L . multiparus was capable of significantly better utilization of lucerne pectin than pectin from sugar beet or apple . The source of pectin was less important for mixed cultures of rumen microorganisms than for pure cultures of rumen bacteria . The amount of fermentation products in the culture fluids supported the conclusion that citrus pectin was utilized better than others . Microbial protein content in the cultures was found to be a less sensitive indicator of pectin utilization than the remaining examined parameters . P . ruminicola strains and mixed cultures of rumen microorganisms were shown to have the highest ability to utilize pectins, L . multiparus-moderate, while the B . fibrisolvens strains utilized pectin the least.

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