The Fermentation of Carbohydrates in the Rumen of the Sheep

1. Acetic, propionic and butyric acids are the main volatile fatty acids in the rumen of the sheep. Acetic acid accounts for 55-75% of the total. 2. Cellulose, glucose and lactic acid are rapidly fermented in vitro by rumen contents with the production of acetic, propionic and butyric acids. Pro-pionic acid is the major component in all cases: very little if any butyric acid is formed from cellulose. 3. The in vitro fermentation of glucose closely resembles the in vivo. 4. The in vitro fermentation of dried grass yields the same three acids, but with acetic acid predominating. 5. Members of the genus Propionibacterium have been isolated from the rumen, and evidence is presented to show that these organisms are responsible for the production of the propionic acid found in the rumen. 6. The dietary history of the animal is shown to influence the rate at which glucose is fermented in the rumen, and the composition of the rumen microflora.

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The production and absorption of volatile fatty acids from the rumen of the sheep

Australian Journal of Agricultural Research ◽

10.1071/ar9680791 ◽

1968 ◽

Vol 19 (5) ◽

pp. 791 ◽

Cited By ~ 7

Author(s):

GJ Faichney

Keyword(s):

Fatty Acids ◽

Acetic Acid ◽

Butyric Acid ◽

Volatile Fatty Acids ◽

Metabolizable Energy ◽

The Other ◽

In Vitro Fermentation ◽

The Mean ◽

The Difference

Experiments are reported in which sheep were given roughage diets or a high concentrate diet and the VFA absorbed from the rumen were estimated by an in vitro fermentation procedure. The VFA absorbed were compared with the digestible and metabolizable energy intakes of the sheep, determined in digestibility trials, for each diet. For a lucerne diet, a straw diet, and the high concentrate diet the proportions of the digested energy absorbed as VFA were 33.6, 42.4, and 33.2% respectively. On the lucerne diet, the difference between the mean molar proportions of the VFA absorbed and the mean molar proportions of the VFA in the rumen approached significance for acetic acid (P < 0.10) and was highly significant for butyric acid (P < 0.01). The differences were not significant for the other diets.

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Passage of protozoa and volatile fatty acids from the rumen of the sheep and from a continuous in vitro fermentation system

British Journal Of Nutrition ◽

10.1079/bjn19740087 ◽

1974 ◽

Vol 32 (2) ◽

pp. 341-351 ◽

Cited By ~ 230

Author(s):

R. A. Weller ◽

A. F. Pilgrim

Keyword(s):

Fatty Acids ◽

Volatile Fatty Acids ◽

Rumen Fluid ◽

In Vitro Fermentation ◽

Fermentation System

1. A procedure for sampling digesta from within the omasal canal of sheep given a variety of roughage diets was used to enable comparison to be made of the composition of effluent from the reticulo-rumen with that of rumen fluid.2. Concentrations of protozoa in effluents, relative to a soluble marker continuously infused intraruminally, were usually less than 20% of corresponding rumen fluid concentrations. It was estimated that the amount of protozoal nitrogen leaving the rumen represented less than 2% of dietary N.3. Passage of volatile fatty acids (VFA) from the rumen in effluent was less than 75% of that indicated by rumen concentrations.4. A continuous, in vitro fermentation system was developed, in which outputs of protozoa were comparable with in vivo outputs.

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Pilot Study of the Effects of Polyphenols from Chestnut Involucre on Methane Production, Volatile Fatty Acids, and Ammonia Concentration during In Vitro Rumen Fermentation

Animals ◽

10.3390/ani11010108 ◽

2021 ◽

Vol 11 (1) ◽

pp. 108

Author(s):

Yichong Wang ◽

Sijiong Yu ◽

Yang Li ◽

Shuang Zhang ◽

Xiaolong Qi ◽

...

Keyword(s):

Fatty Acids ◽

Acetic Acid ◽

Propionic Acid ◽

Acid Content ◽

Volatile Fatty Acids ◽

Rumen Fermentation ◽

Gas Production ◽

Quadratic Response ◽

In Vitro Rumen Fermentation

Nutritional strategies can be employed to mitigate greenhouse emissions from ruminants. This article investigates the effects of polyphenols extracted from the involucres of Castanea mollissima Blume (PICB) on in vitro rumen fermentation. Three healthy Angus bulls (350 ± 50 kg), with permanent rumen fistula, were used as the donors of rumen fluids. A basic diet was supplemented with five doses of PICB (0%–0.5% dry matter (DM)), replicated thrice for each dose. Volatile fatty acids (VFAs), ammonia nitrogen concentration (NH3-N), and methane (CH4) yield were measured after 24 h of in vitro fermentation, and gas production was monitored for 96 h. The trial was carried out over three runs. The results showed that the addition of PICB significantly reduced NH3-N (p < 0.05) compared to control. The 0.1%–0.4% PICB significantly decreased acetic acid content (p < 0.05). Addition of 0.2% and 0.3% PICB significantly increased the propionic acid content (p < 0.05) and reduced the acetic acid/propionic acid ratio, CH4 content, and yield (p < 0.05). A highly significant quadratic response was shown, with increasing PICB levels for all the parameters abovementioned (p < 0.01). The increases in PICB concentration resulted in a highly significant linear and quadratic response by 96-h dynamic fermentation parameters (p < 0.01). Our results indicate that 0.2% PICB had the best effect on in-vitro rumen fermentation efficiency and reduced greenhouse gas production.

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Effect of Lactic Acid Bacteria on the Pharmacokinetics and Metabolism of Ginsenosides in Mice

Pharmaceutics ◽

10.3390/pharmaceutics13091496 ◽

2021 ◽

Vol 13 (9) ◽

pp. 1496

Author(s):

Ji-Hyeon Jeon ◽

Jaehyeok Lee ◽

Jin-Hyang Park ◽

Chul-Haeng Lee ◽

Min-Koo Choi ◽

...

Keyword(s):

Lactic Acid ◽

Lactic Acid Bacteria ◽

Formation Rate ◽

Plasma Concentrations ◽

Control Level ◽

In Vitro Fermentation ◽

Fecal Recovery ◽

Fermentation Test

This study aims to investigate the effect of lactic acid bacteria (LAB) on in vitro and in vivo metabolism and the pharmacokinetics of ginsenosides in mice. When the in vitro fermentation test of RGE with LAB was carried out, protopanaxadiol (PPD) and protopanaxadiol (PPD), which are final metabolites of ginsenosides but not contained in RGE, were greatly increased. Compound K (CK), ginsenoside Rh1 (GRh1), and GRg3 also increased by about 30%. Other ginsenosides with a sugar number of more than 2 showed a gradual decrease by fermentation with LAB for 7 days, suggesting the involvement of LAB in the deglycosylation of ginsenosides. Incubation of single ginsenoside with LAB produced GRg3, CK, and PPD with the highest formation rate and GRd, GRh2, and GF with the lower rate among PPD-type ginsenosides. Among PPT-type ginsenosides, GRh1 and PPT had the highest formation rate. The amoxicillin pretreatment (20 mg/kg/day, twice a day for 3 days) resulted in a significant decrease in the fecal recovery of CK, PPD, and PPT through the blockade of deglycosylation of ginsenosides after single oral administrations of RGE (2 g/kg) in mice. The plasma concentrations of CK, PPD, and PPT were not detectable without change in GRb1, GRb2, and GRc in this group. LAB supplementation (1 billion CFU/2 g/kg/day for 1 week) after the amoxicillin treatment in mice restored the ginsenoside metabolism and the plasma concentrations of ginsenosides to the control level. In conclusion, the alterations in the gut microbiota environment could change the ginsenoside metabolism and plasma concentrations of ginsenosides. Therefore, the supplementation of LAB with oral administrations of RGE would help increase plasma concentrations of deglycosylated ginsenosides such as CK, PPD, and PPT.

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Effects of some poorly digestible carbohydrates on bile acid bacterial transformations in the rat

British Journal Of Nutrition ◽

10.1079/bjn19890011 ◽

1989 ◽

Vol 62 (1) ◽

pp. 103-119 ◽

Cited By ~ 38

Author(s):

Claude Andrieux ◽

Daniele Gadelle ◽

Christine Leprince ◽

E. Sacquet

Keyword(s):

Lactic Acid ◽

Bile Acid ◽

Cholic Acid ◽

Volatile Fatty Acids ◽

Dietary Treatment ◽

Bacterial Transformation ◽

Carbohydrate Feeding ◽

Fermentable Carbohydrates

The effects of ingestion of poorly digestible carbohydrates on bacterial transformations of cholic acid and β-muricholic acid were studied in rats fed on increasing levels of lactose, lactulose, amylomaize or potato starches. Each level was given for 3 weeks and, at the end of each dietary treatment, bile acid faecal composition was analysed and a group of six rats was killed every 4 h during 24 h to determine the amounts of fermented carbohydrate and fermentation characteristics (caecal pH, volatile fatty acids (VFA) and lactic acid concentrations). Fermentation of carbohydrates decreased caecal pH and enhanced caecal VFA and lactic acid concentrations. Irrespective of the poorly digestible carbohydrate, the variation of bacterial transformation always occurred in the same way: the bacterial transformation of β-muricholic acid into hyodeoxycholic acid was the first to disappear, while ω-muricholic acid formation increased; second, cholic acid transformation decreased and finally all bile acid transformations were strongly affected. There was a significant correlation between bile acid transfer and the minimal caecal pH in vivo. This effect of pH was similar in vitro. To determine whether the levels of bacteria which transformed bile acids were modified, rats fed on the highest amounts of poorly digestible carbohydrates were introduced into isolators and carbohydrate feeding was stopped. Caecal pH recovered its initial value but bile acid transformations remained changed, suggesting that the intestinal microflora were modified by ingestion of fermentable carbohydrates.

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Metabolism of propane-1:2-diol infused into the rumen of sheep

British Journal Of Nutrition ◽

10.1079/bjn19720125 ◽

1972 ◽

Vol 27 (3) ◽

pp. 553-560 ◽

Cited By ~ 21

Author(s):

J. L. Clapperton ◽

J. W. Czerkawski

Keyword(s):

Carbon Dioxide ◽

Fatty Acids ◽

Acetic Acid ◽

Lactic Acid ◽

Polyethylene Glycol ◽

Energy Metabolism ◽

Heat Production ◽

Volatile Fatty Acids ◽

Carbon Dioxide Production ◽

Total Volatile

1. Propane-1:2-diol (loog/d) was infused through a cannula into the rumen of sheep receiving a ration of hay and dried grass. The concentration of volatile fatty acids, propanediol, lactic acid and of added polyethylene glycol, and the pH of the rumen contents were measured. The energy metabolism of the sheep was also determined.2. Most of the propanediol disappeared from the rumen within 4 h of its infusion. The infusion of propanediol resulted in a 10% decrease in the concentration of total volatile acids; the concentration of acetic acid decreased by about 30%, that of propionic acid increased by up to 60% and there was no change in the concentration of butyric acid.3. The methane production of the sheep decreased by about 9% after the infusion of propanediol and there were increases in the oxgyen consumption, carbon dioxide production and heat production of the animals; each of these increases was equivalent to about 40% of the theoretical value for the complete metabolism of 100 g propanediol.4. It is concluded that, when propanediol is introduced into the rumen, a proportion is metabolized in the rumen and a large proportion is absorbed directly. Our thanks are due to Dr J. H. Moore for helpful discussions, to Mr D. R. Paterson, Mr J. R. McDill and Mr C. E. Park for looking after the animals and to Miss K. M. Graham, Miss A. T. McKay and Mrs C. E. Ramage for performing the analyses.

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A stringent test for the artificial rumen

Australian Journal of Agricultural Research ◽

10.1071/ar9620343 ◽

1962 ◽

Vol 13 (2) ◽

pp. 343 ◽

Cited By ~ 13

Author(s):

FV Gray ◽

RA Weller ◽

AF Pilgrim ◽

GB Jones

Keyword(s):

Fatty Acids ◽

Volatile Fatty Acids ◽

Artificial Saliva ◽

Two Systems ◽

Stringent Test ◽

Specific Activities

In each of three experiments the acetic, propionic, and butyric acids in the rumen of a sheep were labelled with 14C and a sample of the rumen contents was removed to an artificial rumen so that fermentations of the same substrates could be conducted simultaneously in vivo and in vitro. The in vitro fermentations were carried out in a specially designed artificial rumen of the "permeable" type in which the volume of the contents was kept constant while a continuous supply of artificial saliva was introduced. The relationships between the specific activities of the volatile fatty acids during a period of 2 to 3 hr indicated that the relative rates of formation of the acids were similar in the two systems, although in each experiment the fermentation appeared to proceed more slowly in vitro. It is considered that the procedure constitutes a stringent test for the correct functioning of an artificial rumen.

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