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PubMed2000

Misleading results of ethanol analysis in urine specimens from rape victims suffering from diabetes.

We report appreciably high concentrations of ethanol (82 and 102 mg/dL) in specimens of urine collected from two victims of date rape. Both girls (aged 15 and 18 years) suffered from diabetes mellitus, but adamantly denied drinking any alcohol before or after the incident. The presence of glycosuria and high risk of fungal infections in female diabetics suggests that ethanol was produced in vitro by fermentation after voiding. Making a routine test for sugar in the urine and ensuring that the sampling tubes contain sufficient sodium or potassium fluoride to inhibit glycolysis are recommended practices. A specific marker for post-sampling synthesis of ethanol might also be used such as the 5HTOL/5HIAA ratio.

Journal Article↗
PubMed1988

Production of acids from inulin by a mixed culture of rumen microorganisms.

The production of volatile fatty acids (VFA) and lactic acid from inulin (plant fructan with 2-1 bonds) in in vitro rumen fermentations was followed. The experiments were performed with inocula from wethers receiving two rations, with two pH regimes and using as inocula either whole rumen contents or the corresponding rumen fluid. The following results were obtained: The VFA production was higher when using inocula from hay and concentrate fed wethers. In contrast to this, the lactic acid production was higher when using inocula from hay fed wethers. The VFA production tends to be higher in a weakly acid medium than in a neutral medium. Acetate-to-propionate molar ratio was lower at lower pH. The amounts and composition of the VFA were not different when using both types of inocula. Thus, we believe that micro-organisms colonising plant fibres obviously do not play an important role in inulin splitting.

Animal Feed↗
PubMed2006

Cross-feeding between Bifidobacterium longum BB536 and acetate-converting, butyrate-producing colon bacteria during growth on oligofructose.

In vitro coculture fermentations of Bifidobacterium longum BB536 and two acetate-converting, butyrate-producing colon bacteria, Anaerostipes caccae DSM 14662 and Roseburia intestinalis DSM 14610, with oligofructose as the sole energy source, were performed to study interspecies interactions. Two clearly distinct types of cross-feeding were identified. A. caccae DSM 14662 was not able to degrade oligofructose but could grow on the fructose released by B. longum BB536 during oligofructose breakdown. R. intestinalis DSM 14610 could degrade oligofructose, but only after acetate was added to the medium. Detailed kinetic analyses of oligofructose breakdown by the last strain revealed simultaneous degradation of the different chain length fractions, in contrast with the preferential degradation of shorter fractions by B. longum BB536. In a coculture of both strains, initial oligofructose degradation and acetate production by B. longum BB536 took place, which in turn also allowed oligofructose breakdown by R. intestinalis DSM 14610. These and similar cross-feeding mechanisms could play a role in the colon ecosystem and contribute to the combined bifidogenic/butyrogenic effect observed after addition of inulin-type fructans to the diet.

Acetates↗
PubMed1978

Isolation and phenotypic characterization of virulence-deficient mutants of Vibrio cholerae.

Mutants of Vibrio cholerae was isolated on the basis of reduced ability to induce diarrhea in orally challenged infant mice. Nitrosoguanidine-treated clones were screened for low fluid accumulation ratios in individual mice, and presumptive mutants were confirmed in additional mouse tests. Mutants were examined for alterations in phage type, motility, toxin production, proteolytic activity, neuraminidase production, amylase production, morphology, growth requirements, carbohydrate fermentations, in vitro growth patterns, and cell surface alterations. The types of mutants found included several with previously recognized virulence-associated markers (rough, nonmotile, toxin deficient, protease deficient); several types with pleiotropic alterations (cell morphology, decreased extracellular products); and several with no previously recognized virulence-deficient phenotype (purine requiring, cell surface altered, rapid death in vitro, no defect found). Dose-response kinetics showed that most mutants could provoke diarrhea if given in 100-fold greater numbers than the dose used for screening. Recovery of viable organisms from the gut late in infection showed reduction of survival and/or multiplication capacity for the mutants, with variation in the degree of reduction for the different classes.

Animals↗
PubMed1965

VITAMIN REQUIREMENTS OF SEVERAL CELLULOLYTIC RUMEN BACTERIA.

Scott, H. W. (Ohio Agricultural Experiment Station, Wooster), and B. A. Dehority. Vitamin requirements of several cellulolytic rumen bacteria. J. Bacteriol. 89:1169-1175. 1965.-Four strains of cellulolytic bacteria recently isolated from in vitro rumen fermentations were used in this study. Nine water-soluble vitamins were tested in single-deletion and single-addition plus biotin experiments, each with and without charcoal-extracted casein hydrolysate. Bacteroides succinogenes A3C and B21a required only biotin under the above experimental conditions. Ruminococcus flavefaciens B34b showed an absolute requirement for biotin and was stimulated by p-aminobenzoic acid (PABA) in the single-deletion experiments. In the single-addition plus biotin experiments, PABA and, to a lesser extent, vitamin B(12) appeared to be required for maximal growth. The presence or absence of casein hydrolysate did not affect the vitamin requirements for the aforementioned three strains. In the single-deletion experiments, R. flavefaciens Cla showed an absolute requirement for biotin and, when casein hydrolysate was omitted, for B(12). When casein hydrolysate was present, no requirement for B(12) could be observed. In the single-addition experiments where the basal medium contained biotin and casein hydrolysate or B(12), PABA was required for maximal growth; however, the single deletion of PABA caused only slight retardation of growth. Investigation of the B(12) or casein hydrolysate requirement of Cla revealed that a mixture of purified amino acids simulating casein hydrolysate satisfied this requirement. Subsequent work indicated that this requirement could be satisfied by the amino acid methionine.

4-Aminobenzoic Acid↗
PubMed2005

Corn hybrid affects in vitro and in vivo measures of nutrient digestibility in dogs.

Corn is a commonly used ingredient in dry pet foods because there is a stable supply and it is a relatively inexpensive source of nutrients. Corn hybrids are available that are higher in CP and amylose and lower in phytate concentration than conventional hybrids. Approximately 500 mg of high-protein (HP), high-protein, low-phytate (HPLP), and high-amylose (HA) corn were compared with conventional (CONV) corn and amylomaize starch (AM) in triplicate and exposed to pepsin/hydrochloric acid and pancreatin to simulate hydrolytic digestion. Substrate remaining after this was used to determine in vitro colonic fermentation. Organic matter disappearances as a result of hydrolytic digestion were >80% for CONV, HP, and HPLP, whereas HA (60.7%) and AM (43.7%) were lower (P < 0.05). Total digestion (TD) values after hydrolytic digestion and 8 h of fermentation using canine fecal inoculum were greater (P < 0.05) for CONV, HP, and HPLP vs. HA and AM. The residue left after hydrolytic digestion of all substrates was poorly fermented. Five ileal-cannulated dogs were fed each corn hybrid at approximately 31% of the diet in a 5 x5 Latin square design. Dogs fed diets containing HP corn had higher (P < 0.05) ileal OM digestibility (70.3%) and tended (P < 0.10) to have higher DM digestibility (64.6%). Ileal starch digestibilities were lower (P < 0.05) for dogs fed HA (64.0%) and AM (63.0%). Ileal digestibilities of essential (71.2%), nonessential (67.4%), and total (69.0%) AA tended to be higher (P < 0.10) for HP diets compared with CONV (66.4, 62.4, and 64.0%, respectively). Total-tract DM, OM, CP, and GE digestibilities (77, 82, 77, and 84%, on average, respectively) were higher (P < 0.05) for dogs fed CONV, HP, and HPLP than for those fed AM (66.9, 71.6, 72.6, and 76.5%) and HA (60.6, 65.7, 69.7, and 71.5%). Total-tract fat digestibilities were lower (P < 0.05) for dogs fed HA diets (86.6%) than for all other treatments (91.0%, on average). Total-tract starch digestibilities were higher (P < 0.05) for dogs fed CONV, HP, and HPLP (98%, on average) compared with HA (72.8%) and AM (76.5%). No differences were detected among treatments in fecal bifidobacteria, lactobacilli, or Clostridium perfringens concentrations. The experiments demonstrated that HP and HPLP corn had hydrolytic digestion and fermentation characteristics similar to those of CONV corn, whereas HA resulted in similar responses to AM, a well-established resistant starch ingredient.

Acids, Acyclic↗
PubMed1989

Effects of dry corn gluten feed on feedlot cattle performance and fiber digestibility.

Effects of dry corn gluten feed (DCGF) on feedlot cattle performance and fiber digestibility were investigated. In Trial 1, 120 growing steers were fed corn silage-based diets containing 0, 40, 60 or 80% DCGF. Increasing levels of DCGF resulted in a curvilinear response in gain (P less than .05) and a linear increase in feed/gain (P less than .01). When the same steers subsequently were fed the same levels of DCGF in corn-based diets (Trial 2), increasing the percentage of dietary DCGF resulted in a linear decrease in gain (P less than .01) and a linear increase in feed/gain (P less than .01). In Trial 3, 46 crossbred steers were fed individually in a 2 x 2 factorial design to determine effects of 60 or 80% dietary high-moisture corn (HMC) or DCGF on feedlot cattle performance. Steers fed HMC had faster (P less than .08) and more efficient (P less than .05) gains than those fed DCGF, which had greater feed intakes (P less than .05). In Trial 4, 120 Angus crossbred steers were used to compare effects of 20 or 40% dietary HMC or DCGF on feedlot performance. Steers fed diets containing 40% HMC or DCGF had greater gains (P less than .01) and feed intakes (P less than .01) than those fed 20% diets. Steers fed HMC gained more efficiently than those fed DCGF (P less than .01). In an in situ trial, 0, 40, 60 or 80% dietary DCGF did not affect in situ DCGF DM or NDF disappearance. When DCGF was fermented in vitro in combination with corn silage, increasing the level of DCGF from 0 to 100% resulted in a linear increase (P less than .01) in 24 and 48 h NDF disappearance. These results suggest that at high dietary levels DCGF will support feedlot cattle gains that are nearly equal to those of cattle fed corn silage but somewhat less than those fed corn.

Animal Feed↗
PubMed1994

Faecal DL-lactate concentration in 100 gastrointestinal patients.

The relation between faecal DL-lactate and intestinal inflammation or malabsorption was evaluated in 100 nonselected inpatients at a referral center for gastrointestinal disorders. Twenty-one (21%) had DL-lactate concentrations (range, 8-95 mmol/l) above the 95% limit (6.1 mmol/l) in healthy individuals. Inflammatory bowel disease with active proctitis was associated with increased faecal DL-lactate in 11 of 15 patients (73%) (mean, 32 mmol/l; range, 8-95 mmol/l) and in the 1 patient with pouchitis (8 mmol/l), whereas only 1 of 8 patients (13%) with active inflammatory bowel disease without proctitis had L-lactate elevation (25 mmol/l). Among 26 patients with malabsorption and quiescent or noninflammatory bowel disease, 3 of 17 (18%) with preserved colonic function and 3 of 9 (33%) with jejunostomy had increased faecal lactate. Only 2 of 50 (4%) patients with neither active inflammatory bowel disease nor malabsorption had faecal DL-lactate elevation. In vitro bacterial fermentation of most dietary polysaccharides did not cause accumulation of lactate, corresponding to a lack of correlation between faecal carbohydrate excretion and lactate accumulation. An isolated increase in faecal L-lactate was observed in 6 of 13 patients with inflammatory bowel disease, whereas D-lactate was not increased without a simultaneous increase of the L-lactate isomer. In conclusion, the faecal lactate concentration was frequently increased in patients with inflammatory bowel disease and proctitis, occasionally increased in patients with severe malabsorption, and often normal in patients with quiescent inflammatory bowel disease or localized Crohn's ileitis.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1977

Synthesis and testing of glucose derivatives for feeding to ruminants.

Glucose compounds were synthesized and tested for resistance in a 48-h in vitro rumen fermentation. Glucose complexed with formaldehyde, acetaldehyde, and acetone was resistant. When complexed with propionic and succinic acids, the products readily fermented. The resistant compounds also withstood acid hydrolysis at a pH similar to that of the abomasum. This suggests that these products would have little value as a dietary source of glucose for ruminants if the release of glucose to the animal depended on acid hydrolysis in the abomasum. The possibility of enzymatic hydrolysis of glucose-formaldehyde compound was studied in a feeding trial with sheep. Eight Finncross wethers were fed the formaldehyde product in three quantities in their diet. Blood and urine glucose plus blood, urine, and fecal total soluble carbohydrate were measured. It appears that this glucose-formaldehyde product resists rumen fermentation but does not become metabolically available to sheep as indicated by large quantities of product excreted in urine and feces.

Abomasum↗
PubMed2000

Effects of diet on rumen proliferation and fecal shedding of Escherichia coil O157:H7 in calves.

Calves inoculated with Escherichia coli O157:H7 and fed either a high-roughage or high-concentrate diet were evaluated for rumen proliferation and fecal shedding of E. coli O157:H7. Calves fed the high-roughage diet had lower mean rumen volatile fatty acid concentrations and higher rumen pH values than did calves fed the high-concentrate diet. Despite these differences in rumen conditions, the calves fed the high-roughage diet did not have greater rumen populations of E. coli O157: H7 and did not exhibit increased or longer fecal shedding compared with the calves fed the high-concentrate diet. Two calves shedding the highest mean concentrations of E. coli O157:H7 were both fed the high-concentrate diet. There was a significant (P < 0.05) positive correlation between fecal shedding and rumen volatile fatty acid concentration in calves fed a high-concentrate diet. The effects of diet on E. coli O157:H7 proliferation and acid resistance were investigated using an in vitro rumen fermentation system. Rumen fluid collected from steers fed a high-roughage diet, but not from steers fed a high-concentrate diet, supported the proliferation of E. coli O157:H7. Rumen fluid from steers fed a high-concentrate diet rapidly induced acid resistance in E. coli O157:H7. The impact of diet on fecal shedding of E. coli O157:H7 is still unclear and may depend on dietary effects on fermentation in the colon and on diet-induced changes in the resident microflora. However, rapid development of acid tolerance by E. coli O157:H7 in the rumens of calves fed high-concentrate diets, allowing larger populations to survive passage through the acidic abomasum to proliferate in the colon, may be one factor that influences fecal shedding in cattle on feed.

Animal Feed↗
PubMed1992

A novel inositol mono-phosphatase inhibitor from Memnoniella echinata. Producing organism, fermentation, isolation, physicochemical and in vitro biological properties.

A novel inositol mono-phosphatase inhibitor, L-671,776 (1), was discovered from a culture of the hyphomycete, Memnoniella echinata (ATCC 20928). 1 has a molecular weight of 388 and a molecular formula of C23H32O5. The mode of inhibition is non-competitive, with a Ki of 450 microM. It shows no inhibition of myo-inositol 1,4-bisphosphate 1-phosphatase or myo-inositol 1,4,5-triphosphate 5-phosphatase, although it weakly inhibits myo-inositol 1,4,5-triphosphate 3-kinase (IC50 = 3 mM). It elevates inositol monophosphates in rat parotid slices (EC50 approximately 3 mM), but abolishes agonist effects. It also produces short-lived contraction of guinea pig trachea at 300 microM.

Animals↗
PubMed2006

In vitro three-stage continuous fermentation of gluco-oligosaccharides produced by Gluconobacter oxydans NCIMB 4943 by the human colonic microflora.

Gluco-oligosaccharides produced by Gluconobacter oxydans NCIMB 4943 from maltodextrin as the source, were evaluated for their fermentability by the human colonic microflora. The selectivity of growth of desirable bacteria in the human colon was studied in a three-stage continuous model of the human large intestine. Populations of bacteria, and their fluctuations as a response to the fermentation, were enumerated using fluorescent in situ hybridization (FISH). The gluco-oligosaccharides resulted in increases in numbers of bifidobacteria and the Lactobacillus/Enterococcus group in all 3 vessels of the system, representing the proximal, transverse and distal colonic areas. The prebiotic indices of the gluco-oligosaccharides were 2.29, 4.23 and 2.74 in V1, V2 and V3 respectively.

Bacteria↗
PubMed1982

[Determination of the digestibility of lignocellulose material using the bag (nylon bag) method].

A trial was performed on wethers to study the digestibility of various lignocellulose materials (LCM) by the nylon bag method. The animals were fed good meadow hay ad lib. with unlimited access to water and mineral lick. The trial showed that LCM digestibility was not influenced by different weights of substrate sample. However, digestibility increased with the time for which the LCM were left to ferment in rumen. Almost 90% or more dry matter of the different substrates (pure sulphate cellulose, barley straw and treated beech sawdust) was digested within 48-hour fermentation in rumen. The situation is similar when the substrates are left to ferment in vitro for 96 hours. The high correlation coefficients calculated from the digestibility values of the substrates in vitro and in vivo testify to this fact. The only exception is untreated beech sawdust in which no such a high correlation was found, mainly owing to its low digestibility. However, this should be verified in other kinds of untreated wood (aspen, maple, ash), but with a higher digestibility. It should be stated that silk with a 50 mu mesh is the best material for the production of the bags.

Animal Feed↗
PubMed1995

[In vitro simulation of rabbit cecal fermentation in a semi- continuous flow fermentor. III. Effect of the quantity of dry matter introduced daily in the fermentor and reproducibility of the method].

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

Amylases↗
PubMed2004

Amylose formulations for drug delivery to the colon: a comparison of two fermentation models to assess colonic targeting performance in vitro.

The purpose of this study was to develop an enzyme-based fermentation system for the in vitro assessment of colonic digestion of amylose films and coatings, and to compare its performance with a conventional fermentation model inoculated with human faecal bacteria. Amylose and ethylcellulose were mixed in different ratios and cast as isolated films, as well as spray coated onto drug-(5-aminosalicylic acid) loaded pellets. Four commercial amylase enzymes were individually screened for their ability to digest amylose cast films. The enzyme from the bacterium Bacillus licheniformis was found to be the most active against this substrate. Digestion of mixed amylose and ethylcellulose films was also observed, with the extent of digestion being proportional to the quantity of amylose present in the film. In terms of product performance, drug release from coated pellets was accelerated in the presence of the enzyme. The results with the enzyme system were comparable to those obtained from a faecal-based fermentation model, thereby suggesting that such a system has practical potential for in vitro screening of putative amylose formulations for colonic drug delivery.

Amylases↗