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PubMed1999

Feeding value of wheat-based thin stillage: in vitro protein degradability and effects on ruminal fermentation.

Two experiments were conducted to evaluate the nutritive value of wheat-based thin stillage as a fluid source for ruminants. In vitro CP degradability of thin stillage was estimated relative to canola meal and heated canola meal in a completely randomized design. Four ruminally cannulated steers were used in a double cross-over design to determine the effects of consuming thin stillage or water as drinking sources on ruminal fermentation traits. The in vitro CP degradability of thin stillage (55.4%) was lower (P<.05) than that of canola meal (59.4%) and higher than that of heated canola meal (31.6%). Ruminal pH for steers consuming thin stillage was higher (P<.05) at 1000 and 1100 and lower (P<.05) at 1900 and 2000 than that for steers consuming water. Total VFA followed a pattern that was the reverse of that reported for pH. Ruminal NH3 N levels were higher (P<.05) for steers fed thin stillage than for water-fed steers through most of the collection period. Ruminal fluid and particulate matter passage rates were not affected by treatment and averaged .165 and .06 /h, respectively. The amount of thin stillage and water that did not equilibrate with the ruminal fluid and, thus, was considered to bypass the rumen was estimated to be 51.9 and 59.2% of total fluid consumed, respectively. Feeding wheat-based thin stillage had no adverse effects on ruminal metabolism.

Animals↗
PubMed1990

Effects of Aspergillus oryzae fermentation extract on fermentation of amino acids, bermudagrass and starch by mixed ruminal microorganisms in vitro.

The objective of this study was to examine the effects of Aspergillus oryzae fermentation extract (Amaferm) on the in vitro ruminal fermentation of coastal bermudagrass, soluble starch and amino acids. Mixed ruminal microorganisms were incubated in anaerobic media for either 24 h (Amaferm alone, soluble starch, amino acids) or 48 h (bermudagrass). Amaferm was added to the incubation bottles (n = 4) at concentrations of 0, .4 or 1.0 g/liter. When mixed ruminal microorganisms were incubated with only Amaferm, the 1.0 g/liter concentration increased the production of hydrogen (H2; P less than .001), methane (CH4; P less than .01), acetate (P less than .05), butyrate (P less than .01), total VFA (P less than .05) and NH3 (P less than .05). Addition of both levels of Amaferm to soluble-starch fermentations tended to enhance the production of H2 (P less than .11), CH4 (P less than .15), acetate (P less than .29) and total VFA (P less than .19); propionate production was increased (P less than .10) by 1.0 g/liter Amaferm, resulting in a decrease (P less than .05) in the acetate:propionate ratio. Fermentation of amino acids plus 1.0 g/liter Amaferm enhanced the production of acetate (P less than .05), propionate (P less than .05), valerate (P less than .01) and total VFA (P less than .10) and decreased the acetate:propionate ratio (P less than .05). In addition, NH3 production tended (P less than .19) to increase with both levels of Amaferm. When bermudagrass was the substrate, few changes in fermentation products were observed with Amaferm treatment.(ABSTRACT TRUNCATED AT 250 WORDS)

Amino Acids↗
PubMed2001

Effect of nitrogen source in high-concentrate, low-protein beef cattle diets on microbial fermentation studied in vivo and in vitro.

In Exp. 1, four Holstein heifers (112+/-5.5 kg BW) fitted with ruminal cannulas were used in a 4 x 4 Latin square to evaluate the effects of N source on ruminal fermentation and urinary excretion of purine derivatives. A 2 x 2 factorial arrangement of treatments was used; the factors were the type of protein source (soybean meal, SBM, vs a 50:50 mixture of fish meal and corn gluten meal, FMCGM) and the partial substitution of protein source by urea (with vs without). Heifers were allowed to consume concentrate and barley straw on an ad libitum basis. Barley straw:concentrate ratio (12:88) and average ruminal pH (6.25) were not affected (P > 0.05) by treatment. Ruminal NH3 N concentration and urinary excretion of purine derivatives were not affected (P > 0.05) by supplemental N source. In situ CP degradability of supplemented SBM was very low (50%). In Exp. 2, eight dual-flow continuous-culture fermenters were used to study diet effects on microbial fermentation and nutrient flow, using forage:concentrate ratio, solid and liquid passage rates, and pH fluctuation to simulate in vivo conditions. The treatment containing SBM without urea reached the greatest total VFA concentration (P < 0.01), molar percentage of acetate (P < 0.05), and NH3 N concentration (P < 0.05), followed by treatments with partial substitution of protein source by urea, and finally by the treatment containing FMCGM. True OM digestion tended to increase (P = 0.13) in treatments containing SBM. These results suggest that amino N from SBM and NH3 N concentration stimulated nutrient digestion. Microbial protein synthesis was lowest in treatments with FMCGM and without urea, indicating that rapidly available N limited microbial growth. The low CP degradability of SBM observed may have contributed to the limitation in N supply for microbial growth. Efficiency of microbial protein synthesis increased in treatments containing urea (P < 0.05). Protein source affected total (P < 0.05) and essential AA (P < 0.10) flows, which were greater in treatments containing FMCGM. Partial replacement of protein supplements by urea did not affect total and essential AA flows. Because mean dietary protein contribution to total N effluent was 46%, the AA profile of supplemental protein sources had a great impact on total AA flow and its profile.

Amino Acids↗
PubMed1998

Fermentation of non-starch polysaccharides in mixed diets and single fibre sources: comparative studies in human subjects and in vitro.

The present study investigated whether the extent of fermentation of NSP in human subjects could be predicted by an in vitro batch system. Fibre sources studied were five mixed diets containing different amounts and types of fibre and three single fibre sources (citrus fibre concentrate, coarse and fine wholemeal rye bread). Fermentation in human subjects was determined in balance experiments in women who were also donors of the faecal inocula. In vitro fermentations were performed with fibre residues prepared from duplicates of the fibre-containing foods consumed during the balance trials. Fermentation of total NSP in vivo was between 65.8 and 88.6% for the mixed diets and 54.4, 58.0 and 96.9% for the coarse and fine wholemeal rye breads and the citrus fibre concentrate respectively. For the mixed diets and the citrus fibre concentrate, mean differences between the extent of NSP degradation after 24 h in vitro incubation and that in vivo were between -0.7 and 5.0%. Differences were significant for one diet (P < 0.05). For the wholemeal rye breads, the fermentation in vitro exceeded that in vivo significantly, but the magnitude of the difference in each case was small and without physiological importance. Particle size of breads had no influence on the extent of NSP degradation. These results indicate that the in vitro batch system used could provide quantitative data on the fermentation in vivo of NSP in mixed diets and some single fibre sources. An in vitro incubation time of 24 h was sufficient to mimic the NSP degradation in vivo.

Adult↗
PubMed2006

In vitro assessment of properties associated with the survival through the gastro-intestinal tract of staphylococci isolated from traditional sausage fermentation.

Thirteen Staphylococcus sp. strains, previously isolated from spontaneous sausage fermentation, were in vitro examined for properties associated with their ability to survive through the gastro-intestinal tract. None of the strains were able to survive exposure to pH 1 or pH 2, while for most of them, a population reduction, ranging from 77.3% to 99.0% and a surviving population from 1.7 x 10(8) to 9.0 x 10(6) was observed after exposure to pH 3. None of the strains exhibited bile salt hydrolase activity or production of antimicrobial compounds, while all of them were resistant to pancreatin. Only S. cohnii cohnii LQC 5112 was found to be alpha-haemolytic, seven other strains were beta-haemolytic and the rest gamma-haemolytic. All strains were sensitive to erythromycin, ampicillin (but S. intermedius LQC 5023) and chloramphenicol while most of them were sensitive to tetracycline. On the other hand, most of the strains were resistant to novobiocin. Furthermore, their aptitude, not only to withstand, but to proliferate in the presence of bile salts, as well, even at an acidic environment and their ability to adhere to stainless-steel plates, indicate the need for an in vivo study.

Animals↗
PubMed1987

[In vitro effect of 10 antimicrobial agents on the fermentative capacity of the intestinal bacteria].

Using a technique previously described a study was done on the in vitro effect of 10 antimicrobials on the fermentative capacity of human fecal bacteria. The antimicrobials were: 5 antibiotics, oxytetracycline, chloramphenicol, neomycin, paramomycin and lincomycin; and 5 chemotherapeutic agents, bismuth subnitrate, cotrimoxazole, furazolidone, norfloxacin and metronidazole. The study was done with 162 stool samples, 27 to investigate the effect of bismuth subnitrate, and 135 to investigate the effect of the remaining 9 antimicrobials (15 for each one of them). The quantities of antimicrobials used were calculated to reproduce in vitro minimal inhibitory concentrations against fecal bacteria and/or concentrations reached by the respective antimicrobials or their active metabolites in the colonic contents or the stools after regular oral doses. For greater simplicity and clarity, whenever two concentrations of an antimicrobial were reproduced they were denominated low concentration and high concentration as it corresponded. Oxytetracycline, neomycin, paramomycin, cotrimoxazole and norfloxacin did not significantly affect fermentation by fecal bacteria. Chloramphenicol, lincomycin, bismuth subnitrate and furazolidone did not seem to affect significantly fermentation when the variations, increases and decreases produced in it, where evaluated as a whole. But, when increases and decreases were evaluated separately it was found that: chloramphenicol, at low concentration, increase fermentation significantly with 11 from 15 stool samples and diminished it although not significantly with the remaining 4 samples, and at high concentration, increased fermentation significantly with 8 from the 15 samples and diminished it although not significantly with the remaining 7 samples; lincomycin, at low concentrations, increased fermentation with 6 from 15 stool samples and diminished it with the remaining 9 samples although not significantly, and at high concentration, increased it significantly with 9 from the 15 samples and diminished it although not significantly with the remaining 6 samples; bismuth subnitrate, at low concentration, increased fermentation although not significantly with 5 from 27 stool samples and diminished it significantly with the remaining 22 samples, and at high concentration, increased it although not significantly with 2 from 10 stool samples and diminished it significantly with the remaining 8 samples; and furazolidone, at a unique concentration, increased fermentation significantly with 9 from 15 stool samples and diminished it although not significantly with the remaining 6 samples.(ABSTRACT TRUNCATED AT 400 WORDS)

Anti-Bacterial Agents↗
PubMed2003

Effect of fungi fermentation on organoleptic properties, energy content and in-vitro multienzyme digestibility of cassava products (flour & gari).

The present study sought to investigate the effect of fungi fermentation on the energy content, sensory quality and the digestibility (in vitro) of cassava products (flour and gari). The fungi fermented cassava products (gari and flour) were produced, by fermenting cassava mash with pure strains of some common saprophytes, namely, Aspergillus flavus, Aspergillus niger, Rhizopus oryzae and Saccharomyces spp (Baker's yeast and palm wine yeast) for 72 hrs before processing into cassava flour and gari, the forms in which cassava is popularly consumed in Nigeria. Parameters determined include energy (Bomb calorimetry), digestibility (in vitro) and sensory quality by trained taste panel. The results of the study indicated that fungi fermentation of the cassava mash significantly (P < 0.05) increased the acceptability of the colour, texture, aroma and taste of the "gari", with that of Rhizopus oryzae fermentation having the highest general acceptability. Furthermore, the results also indicated that fungi fermentation of cassava mash significantly increased (P < 0.05) the in vitro multienzyme protein digestibility of the cassava products. In view of this, fungi fermentation could be used to improve the sensory quality and protein digestibility of cassava products without any significant (P > 0.05) effect on the energy-giving role of cassava products.

Aspergillus flavus↗
PubMed1996

In vitro study of the age-dependent caecal fermentation pattern and methanogenesis in young rabbits.

The caecal fermentation pattern, including methanogenesis, was studied in young rabbits using in vitro batch incubations. Six conventional litters of eight rabbits each were used. At the age of 22, 25, 28, 32, 36, 42 and 56 days, an animal was slaughtered from each litter and its caecal contents were used for in vitro batch incubations at 39 degrees C/24 h. The incubated samples were analysed for volatile fatty acids (VFA), methane, hydrogen, ammonia nitrogen (NH3-N) and lactic acid (LA). The net total in vitro VFA production did not differ clearly with age, although a significant decrease was observed on day 36, reflecting the reduced zootechnical performances probably related to an infection with Clostridium spiroforme that occurred in the same period. The molar proportions of butyrate and propionate formed a change in the opposite direction with age, starting with a sudden shift from propionate to butyrate at day 25. In vitro NH3-N production was suggestive of a progressive and significant decrease with age; in vitro LA production was always low. Methane production was almost absent from fermentation until 32 days of age, after which it suddenly shifted from 1.6 to 52.0 mumol/flask/day and increased further with age. A significant litter effect on methanogenesis was observed which suggested the existence of a genetic effect. The hydrogen production was quite low and decreased significantly from day 36 with increasing methanogenesis. The calculated hydrogen recoveries showed a gradual increase from day 32 and were positively correlated (r = 0.92) with methane production. In conclusion, it would seem that in young suckling rabbits, reductive acetogenesis is a major characteristic of caecal fermentation, to be replaced gradually and partially by methanogenesis with the increasing intake of solid feed.

Aging↗
PubMed2000

TAN-1813, a novel Ras-farnesyltransferase inhibitor produced by Phoma sp. taxonomy, fermentation, isolation and biological activities in vitro and in vivo.

A novel Ras-farnesyltransferase inhibitor designated TAN-1813 was isolated from the culture broth of a fungus strain, FL-41510, isolated as a plant endophyte. The producer was taxonomically characterized as Phoma sp. FL-41510. TAN-1813 inhibited rat brain farnesyltransferase and geranylgeranyltransferase I activity with IC50 values of 23 microg/ml and 47/microg/ml, respectively. TAN-1813 showed mixed-type inhibition with respect to farnesylpyrophosphate and noncompetitive inhibition with respect to a K-Ras C-terminal peptide. It also inhibited the in situ farnesylation of cellular Ras proteins in a K-ras transformant (NIH3T3/K-ras) of mouse embryonic fibroblast cell line NIH3T3. TAN- 1813 inhibited the proliferation of various human cancer cells, some of which harbor activated ras alleles, with IC50 values of 15 approximately 110 ng/ml as well as that of NIH3T3 and NIH3T3/K-ras cells with IC50S of 540 and 310 ng/ml, respectively. Flow cytometric analysis indicated that TAN-1813 arrests NIH3T3/K-ras cells at both G1 and G2/M phases of the cell cycle. In addition, TAN-1813 was found to induce morphological reversion of NIH3T3/K-ras cells from the transformed phenotype. Antitumor activity of TAN-1813 against human fibrosarcoma HT-1080 and NIH3T3/K-ras tumors in nude mice was also verified.

3T3 Cells↗
PubMed1985

[In vitro effect of 2 pharmaceutical preparations containing bismuth on the fermentative capacity of intestinal bacteria].

An investigation was done on the action in vitro of two pharmaceutical preparations containing Bi, De Nol and Pepto Bismol, on the fermentative capacity of intestinal bacteria. For the purpose, using an instrument and a technique previously described, fecal fermentation (FF) was measured in 21 stool samples, to which lactose was added to assure appreciable levels of fermentation. In 11 of the samples, FF was measured without and with addition of De Nol; and in the 10 remaining samples, without and with addition of Pepto Bismol. In 7 of the samples with which the action of De Nol was studied, this preparation significantly reduced FF from 10.9 not equal to 4.3 (mean not equal to s. d.) to 4.9 not equal to 5.0 ml of gas/24 h (p less than 0.02); on the contrary, in the 4 remaining samples, it increased FF, although not significantly, from 8.7 not equal to 4.8 to 16.7 not equal to 8.8 ml of gas/24 h (N.S.). Pepto Bismol significantly reduced FF, in all the 10 samples with which the action of that pharmaceutical - preparation was investigated, from 11.7 not equal to 6.1 to 3.0 not equal to 2.1 ml of gas/24 L (p less than 0.0001). A discussion was done on the possible mechanisms of the antifermentative action of Bi, as well as on the probable usefulness of De Nol and Pepto Bismol for the control of exaggerated intestinal fermentation and the flatulence it frequently causes.

Antacids↗
PubMed2006

Effect of different types of fibre supplemented with sunflower oil on ruminal fermentation and production of conjugated linoleic acids in vitro.

An in vitro study was conducted to determine the effect of different types of fibre supplemented with sunflower oil on ruminal fermentation and formation of conjugated linoleic acids (CLA) by mixed ruminal microorganisms. Cell wall components extracted from wheat straw (representing lignified fibre), soybean hulls (representing easily digestible fibre), and purified cellulose were used as substrates. Sunflower oil was supplemented at the same level for all three types of fibre. After 24 h of incubation, ruminal fermentation parameters (including 24 h gas production, pH value, concentration of ammonia nitrogen and volatile fatty acids) and the concentration of long chain fatty acids in the culture fluid were determined. Results showed that the type of fibre influenced ruminal fermentation traits and the biohydrogenation of unsaturated C18 fatty acids in vitro. Composition of LCFA and profile of CLA were altered by the fibre type. Compared to the digestible fibre and purified cellulose, lignified fibre significantly increased the production of cis-9, trans-11 CLA and total CLA (sum of cis-9, trans-11 CLA, trans-10, cis-12 CLA, trans-9, trans-11 CLA, and cis-9, cis-11 CLA) by ruminal microorganisms. It was concluded that ruminal fermentation and production of CLA can be affected by the type of dietary fibre.

Animal Feed↗
PubMed2004

Differential fermentation of glucose-based carbohydrates in vitro by human faecal bacteria--a study of pyrodextrinised starches from different sources.

BACKGROUND: Pyrodextrins, modified starches produced by heat/acid treatment, have been used extensively in the paper industry. Recently, pyrodextrinisation has been recognised as a way of producing a "resistant starch" that is water-soluble and has non-starch linkages. However, a full characterisation of the fermentation properties of pyrodextrins has not been reported. AIM OF THE STUDY: To evaluate the effect of pyrodextrinisation on the fermentation characteristics of starches, prepared from Venezuelan crops, in a simple in vitro model of the human colon. METHODS: Potato, lentil and cocoyam pyrodextrins were produced using heat (140 degrees C for 3 h) and hydrochloric acid as catalyst (1.82 g/kg starch). Then, both native and modified starches were pre-digested with pepsin and pancreatic enzymes and their resistant components fermented anaerobically using human faeces as inocula for 24 h. Short-chain fatty acids (SCFA), pH, residual starch and carbohydrate in the cultures were measured. RESULTS: More than 69% of initial carbohydrate disappeared from both pre-digested native and pyroconverted starch cultures. More than 6.8 and 10.0 mmol net SCFA per gram carbohydrate were produced from pre-digested native and pyrodextrinised starches, respectively. In cultures of predigested pyrodextrins, the molar ratio for propionate doubled, whereas the ratio of acetate decreased by 25% when compared with pre-digested native starches. The ratio of butyrate did not change. CONCLUSIONS: The mechanism for the change in SCFA profile is unclear, but may be related to solubility and/or presence of nonstarch linkages. The presence of these bonds may modify the accessibility/affinity of bacterial enzymes to the modified starch structure.

Bacteria, Anaerobic↗
PubMed2005

Comparison of different fibers for in vitro production of short chain fatty acids by intestinal microflora.

The fermentation of dietary fiber in the large intestine and the by-products of this fermentation are thought to protect against colonic diseases. As it is difficult to measure the fermentation of dietary fiber in an intact animal, in vitro techniques have been developed to compare the fermentability of various dietary fibers. The objective of this project was to compare short chain fatty acid (SCFA) production with different fibers in an in vitro fermentation model. A wide range of commercially available dietary fiber sources was compared for SCFA production. Fibers were fermented with a fecal innoculum for 0, 2, 4, 8, 12, and 24 hours. SCFAs were measured by gas chromatography. SCFA production varied among the fiber sources. Hydrolyzed guar gum and galactomannan produced the greatest amounts of total SCFAs. Butyrate production was higher with the fiber sources than the glucose control. Acetate production was less for psyllium than the other fibers. Thus, different dietary fiber sources are more readily fermented by fecal microflora. These differences most likely affect the physiological differences seen among dietary fiber sources.

Chromatography, Gas↗
PubMed1996

[Antibacterial activities of combination uses of cefpirome with various antibiotics in vitro against clinically isolated glucose non-fermentative gram-negative rods: part 1. the results against Pseudomonas aeruginosa].

In order to evaluate antibacterial activities of combination uses of cefpirome (CPR) and various antibiotics in vitro, minimum inhibitory concentrations (MICs) of CPR alone and combinations of CPR+other drugs against freshly isolated clinical strains of Pseudomonas aeruginosa. The results are summarized as follows; 1. Combined effects of CPR+beta-lactams, piperacillin (PIPC), aztreonam (AZT), imipenem (IPM) showed wider antibacterial spectra and stronger antibacterial activities than CPR alone with drugs concentrations of CPR and other drugs at sub-MIC levels. At concentrations of sub-MIC levels, antibacterial effects of CPR+PIPC and CPR+AZT combination were strong but CPR+IPM was weaker than those of the former two combinations. It appeared that stronger effects were demonstrated by some combinations against strains that were susceptible to both drugs of combination, but little additive effects were shown against strains that were resistant to both drugs. Antibacterial effect of CPR+fosfomycin combination was the same as those of CPR+PIPC and CPR+AZT combinations. 2. Combined effects of CPR+aminoglycosides (AGs), gentamicin, tobramycin, amikacin showed wider antibacterial spectra and stronger antibacterial activities at sub-MIC levels of CPR or ATs. The effect against CPR-resistant strains was same. But the combined effect was weak against AGs-resistant strains. 3. Effectiveness of combinations of CPR+beta-lactams and CPR+AGs depended on drug susceptibilities of strains tested. We cannot estimate effects of those combinations without investigating drug susceptibility of bacteria being tested. 4. In none of the combinations tested, antagonism was observed.

Amikacin↗
PubMed2005

Effects of disodium fumarate on in vitro rumen microbial growth, methane production and fermentation of diets differing in their forage:concentrate ratio.

The effects of disodium fumarate on microbial growth, CH4 production and fermentation of three diets differing in their forage content (800, 500 and 200 g/kg DM) by rumen micro-organisms in vitro were studied using batch cultures. Rumen contents were collected from four Merino sheep. Disodium fumarate was added to the incubation bottles to achieve final concentrations of 0, 4 and 8 mm-fumarate, and (15)N was used as a microbial marker. Gas production was measured at regular intervals from 0 to 120 h of incubation. Fumarate did not affect (P>0.05) any of the measured gas production parameters. In 17 h incubations, the final pH and the production of acetate and propionate were increased linearly (P<0.001) by the addition of fumarate. Fumarate tended to increase (P=0.076) the organic matter disappearance of the diets and to decrease (P=0.079) the amount of NH3-N in the cultures. Adding fumarate to batch cultures tended (P=0.099) to decrease CH4 production, the mean values of the decrease being 5.4 %, 2.9 % and 3.8 % for the high-, medium- and low-forage diet, respectively. Fumarate tended to increase (P=0.082) rumen microbial growth for the high-forage diet, but no differences (P>0.05) were observed for the other two diets. These results indicate that the effects of fumarate on rumen fermentation depend on the nature of the incubated substrate, the high-forage diet showing the greatest response.

Acetates↗