scholarly journals Comparative effects of dietary wheat bran and its morphological components (aleurone and pericarp-seed coat) on volatile fatty acid concentrations in the rat

1987 ◽  
Vol 57 (1) ◽  
pp. 69-76 ◽  
Author(s):  
Bing-Qin Cheng ◽  
Rodney P. Trimble ◽  
Richard J. Illman ◽  
Bruce A. Stone ◽  
David L. Topping
Keyword(s):  
Seed Coat ◽  
Wheat Bran ◽  
Volatile Fatty Acids ◽  
Male Rats ◽  
Electrostatic Separation ◽  
Hepatic Portal ◽  
Apparent Susceptibility ◽  
Very High ◽  
Bacterial Mass ◽  
Venous Plasma

1. Adult male rats were fed on diets containing 100 g dietary fibre/kg either as α-cellulose or wheat bran or the pericarp-seed coat or aleurone layers prepared from that bran by sequential milling and air elutriation and electrostatic separation.2. After 10 d, concentrations of total volatile fatty acids (VFA) in caecal fluid were significantly different between groups and fell in the order: aleurone > wheat bran > pericarp-seed coat > cellulose. This ranking probably reflected the ease of fermentation of fibre polysaccharides by colonic bacteria which also resulted in a considerably higher faecal bacterial mass in the aleurone group.3. Because of the differences in the volume of caecal digesta, the mass of caecal VFA was considerably the highest in the aleurone group, intermediate with wheat bran and equally low in the pericarp-seed coat and cellulose groups.4. The diet based on aleurone gave a relatively higher proportion of propionate but with both pericarp-seed coat and wheat bran the contribution of butyrate was raised.5. VFA concentrations in hepatic portal venous plasma were proportional to caecal concentrations with very high (> 3 mM) values being recorded in the aleurone group.6. The findings are discussed in relation to the apparent susceptibility of the morphological components of wheat bran to fermentation by large bowel bacteria.

scholarly journals Effects of solvent extraction on the hypocholesterolaemic action of oat bran in the rat

1991 ◽  
Vol 65 (3) ◽  
pp. 435-443 ◽  
Author(s):  
Richard J. Illman ◽  
David L. Topping ◽  
Kerin Dowling ◽  
Rodney P. Trimble ◽  
Gordon R. Russell ◽  
...  
Keyword(s):  
Wheat Bran ◽  
Volatile Fatty Acids ◽  
Cholesterol Metabolism ◽  
Plasma Cholesterol ◽  
Tocopherol Content ◽  
Male Rats ◽  
Cholesterol Feeding ◽  
Oat Bran ◽  
Hepatic Portal Vein ◽  
Hepatic Portal

In adult male rats fed on a cholesterol-free synthetic diet, plasma cholesterol concentrations were lowest with oat bran, intermediate with cellulose and highest with wheat bran. Plasma triacylglycerols (TAG) were similar with wheat bran and cellulose but higher with oat bran. The concentrations and pools of caecal volatile fatty acids (VFA) were lowest with cellulose and equally higher with oat bran and wheat bran. Plasma VFA concentrations in the hepatic portal vein reflected those in caecal digesta and were unrelated to plasma cholesterol. Feeding oat bran after extraction with n-pentane gave plasma cholesterol concentrations similar to that found with wheat bran. Reconstitution of oat bran with extracted lipids did not restore the cholesterol-lowering effect. Addition of the extracted material to a wheat-bran diet had no effect on plasma cholesterol. Plasma TAG were higher with the oat bran and reconstituted-oatbran diets than with wheat-bran or cellulose diets. However, extracted oat bran+safflower oil gave similar TAG concentrations to that with wheat bran. These extractions and additions did not change caecal bile acid or neutral sterol concentrations. Effects of these diets on plasma cholesterol were unrelated to their tocotrienol or tocopherol content. Addition of n-pentane to oat bran followed by evaporation of solvent gave plasma cholesterol concentrations that were significantly higher than untreated oat bran but lower than similarly treated wheat bran. It is concluded that oat bran affects cholesterol metabolism through a pentane-soluble component as well as non-starch polysaccharides. It appears that the activity of this lipid is not transferable by simple addition of the solvent extract to the whole diet.

Effects of Wheat Bran and Porridge Oats on Hepatic Portal Venous Volatile Fatty Acids in the Pig

1985 ◽  
Vol 29 (6) ◽  
pp. 325-331 ◽  
Author(s):  
D.L. Topping ◽  
R.J. Illman ◽  
M.N. Taylor ◽  
G.H. McIntosh
Keyword(s):  
Fatty Acids ◽  
Wheat Bran ◽  
Volatile Fatty Acids ◽  
Hepatic Portal

Incorporation of [1-14C] and [3-14C] butyrate into milk constituents by the perfused cow's udder

1960 ◽  
Vol 27 (2) ◽  
pp. 151-160 ◽  
Author(s):  
Monique Lauryssens ◽  
R. Verbeke ◽  
G. Peeters ◽  
M.-Thérèse Reinards
Keyword(s):  
Fatty Acids ◽  
Sodium Acetate ◽  
Volatile Fatty Acids ◽  
Specific Activity ◽  
Krebs Cycle ◽  
Acid Synthesis ◽  
Satisfactory Explanation ◽  
C Distribution ◽  
Total Fatty Acids ◽  
Very High

SummaryOne half-udder from a lactating cow was perfused for 110 min with blood containing 1 mc of [1-14C]butyrate. Inactive sodium butyrate was added at the eightieth minute. The volume of milk collected was 320 ml. One half-udder from another cow was perfused for 120 min in the presence of 0·5 mc [3-14C]butyrate, inactive sodium acetate being added at the sixtieth minute. The volume of milk collected was 150 ml.The total amount of 14CO2 recovered was 5·7% of the [1-14C]butyrate given and 7·6% of the [3-14C]butyrate given. In both instances casein, followed by the volatile fatty acids, showed the highest specific activity of the constituents isolated from the milk. The glyceride fatty acids in the udder were fifty times as active as those in the milk. With [3-14C]butyrate the activity of the total fatty acids amounted to 24% and that of total lactose to 0·38% of the added 14C. Butyrate did not appear to be used for glycogenesis in the perfused gland. The specific activity of the lower fatty acids of both the udder and the milk increased stepwise with increasing chain length to reach a maximum at C10. A satisfactory explanation for this peculiar 14C distribution cannot be given at the present time. There was no evidence of direct esterification of butyrate. Most of the activity of casein was due to labelled glutamic and aspartic acids, the activity of the former being four times as high as that of the latter. The acids of the Krebs cycle isolated from the udder tissue when [3-14C]butyrate was given showed very high activity. No striking differences were observed between the results of the two experiments. It is concluded that butyrate is split into two C2 components which behave identically. These are utilized for fatty acid synthesis and take part in the Krebs cycle. The relative 14C distribution between the components isolated from milk and those from tissue may be a reflexion of the secretory processes in the udder cells, synthesized fat tending to be secreted in the alveoli after the other constituents.

Comparative rates of formation, in vivo, of 16-androstenes, testosterone and androstenedione in boar testis

1984 ◽  
Vol 103 (2) ◽  
pp. 179-186 ◽  
Author(s):  
E. L. Hurden ◽  
D. B. Gower ◽  
F. A. Harrison
Keyword(s):  
Binding Sites ◽  
Venous Blood ◽  
Peripheral Circulation ◽  
Total Radioactivity ◽  
Venous Blood Flow ◽  
Large White ◽  
The Third ◽  
Very High ◽  
Venous Plasma

ABSTRACT Three mature Large White boars were anaesthetized and received [7(n)-3H]pregnenolone by continuous infusion into right and left spermatic arteries for up to 180 min. Spermatic venous blood flow was measured by separate timed collections of completely diverted outflow from each testis and blood not sampled was returned to the peripheral circulation. The total radioactivity in plasma from each testis increased markedly during the first 60 min of infusion to reach a plateau from 80 to 180 min. Radiolabelling of 5α-androst-16-en-3-one, 5α-androst-16-en-3β-ol and -3α-ol showed similar patterns with ratios of mean radioactivity of 5:3:1 respectively between 80 and 180 min. In comparison, the amounts of tritiated 4,16-androstadien-3-one formed were very small. The radiolabelling of testosterone and 4-androstenedione occurred more rapidly than that of the 16-androstenes and reached maxima by 30 min. However the amounts were only one-fifth (testosterone) and one-tenth (4-androstenedione) those of the combined quantities of tritiated 16-androstenes. Addition of human chorionic gonadotrophin (hCG) to the infusate to one testis in each animal (so that 5000 i.u. hCG were delivered in 15–20 min) produced no change in the outputs of radiolabelled steroids although radioimmunoassay of spermatic venous plasma in samples from the third experiment showed a transient increase in the concentration of 4-androstene-3,17-dione during the hCG infusion. It is suggested the lack of response to hCG could be produced by saturation and down regulation of binding sites by the very high local concentrations of hCG. J. Endocr. (1984) 103, 179–186

scholarly journals Taurocholic acid adsorption during non-starch polysaccharide fermentation: an in vitro study

1995 ◽  
Vol 74 (2) ◽  
pp. 221-228 ◽  
Author(s):  
Ingrid C. Gelissen ◽  
Martin A. Eastwood
Keyword(s):  
Wheat Bran ◽  
Volatile Fatty Acids ◽  
Binding Capacity ◽  
In Vitro Study ◽  
Total Radioactivity ◽  
Taurocholic Acid ◽  
Supernatant Fraction ◽  
Bile Acid Binding ◽  
Highly Correlated

The association of radiolabelled taurocholic acid with the solid fraction of a faecal fermentation mixture was measured. A human faecal inoculum was incubated with [24-14C]taurocholic acid and several non-starch polysaccharide sources (pectin, wheat bran, ispaghula (Plantago ovata) husk and seed), glucose or a substrate-free control. Portions of fermentation mixture were taken at 0, 3, 6, 21 and 24 h and centrifuged to acquire a supernatant fraction and a pellet containing the fermentation residue. 14C was measured in supernatant fractions and pellets at all time points. Volatile fatty acids (VFA) were measured at 0 and 24 h to confirm bacterial growth. Radioactivity in the pellet increased over time for all substrates. Glucose resulted in the greatest incorporation of taurocholic acid into the pellet, followed by pectin. At 24 h the proportion of the total radioactivity found in the pellet was 92% for glucose, 79% for pectin, 60% for wheat bran, 59% for ispaghula seed, 53% for ispaghula husk and 26% for the control (mean of duplicates). Glucose and pectin produced the greatest quantity of VFA at 24 h. VFA production was highly correlated with radioactivity in the pellet (r 0·976, P <0·005). These results suggest that the bile acid binding capacity of a faecal culture mixture may be strongly influenced by the fermentability of the available substrate and hence related to bacterial metabolic activity.

scholarly journals The effects of pectin and wheat bran on the distribution of a meal in the gastrointestinal tract of the rat

1994 ◽  
Vol 72 (2) ◽  
pp. 289-297 ◽  
Author(s):  
N. J. Brown ◽  
A. Greenburgh ◽  
J. Tomlin
Keyword(s):  
Gastrointestinal Tract ◽  
Gastric Emptying ◽  
Gastrointestinal Motility ◽  
Wheat Bran ◽  
Delayed Gastric Emptying ◽  
Physical Characteristics ◽  
Male Rats ◽  
Gastrointestinal Disorders ◽  
Insoluble Fibre ◽  
Bean Meal

The effects of wheat bran and pectin on the gastrointestinal distribution of a radiolabelled, homogenized baked-bean meal were investigated in the rat. These fibres were chosen because of their very different physical characteristics; wheat bran is a coarse, particulate, mainly insoluble fibre whilst pectin is a soluble viscous polysaccharide. Sixty male rats were administered orally with control or test meals and five from each group were killed after 50, 100, 200 and 300 min. The gut was removed and the distribution of the meal established scintigraphically. Addition of the fibres altered the distribution of the meal with faster accumulation at the distal and caecal areas. Wheat bran delayed gastric emptying whilst pectin promoted gastric emptying and had a pronounced effect on increasing the distal accumulation of the meal. These alterations in the distribution of a homogenized baked bean meal show that dietary fibres with different physical characteristics may alter gastrointestinal motility in different ways and these differences may have implications for meal absorption and clinical treatments of gastrointestinal disorders.

scholarly journals A viscous fibre (methylcellulose) lowers blood glucose and plasma triacylglycerols and increases liver glycogen independently of volatile fatty acid production in the rat

1988 ◽  
Vol 59 (1) ◽  
pp. 21-30 ◽  
Author(s):  
David L. Topping ◽  
David Oakenfull ◽  
Rodney P. Trimble ◽  
Richard J. Illman
Keyword(s):  
Fatty Acid ◽  
Dietary Fibre ◽  
Volatile Fatty Acids ◽  
Plasma Cholesterol ◽  
Liver Glycogen ◽  
Acid Synthesis ◽  
High Viscosity ◽  
Male Rats ◽  
Fatty Acid Production ◽  
Arterial Blood

1. Adult male rats were maintained on diets containing 80 g methylcellulose/kg of low (25 cP), medium (400 cP) and high (1500 cP) viscosity.2. After 10 d, the viscosity of stomach and caecal contents was found to have increased in proportion to that of the dietary fibre. Concentrations of volatile fatty acids in caecal digesta were lowest with the high-viscosity fibre but acetate was the major acid present with all three diets. Acetate was the only acid found in significant quantities in hepatic portal venous plasma and concentrations of this acid were unaffected by diet.3. Concentrations of glucose in arterial blood were low with the medium-and high-viscosity diets while the content of liver glycogen was high. These effects of fibre were not directly on glucose absorption as the intestines were net removers of the hexose at the time of sampling.4. Hepatic lipogenesis and plasma triacylglycerol concentrations were both higher in rats fed on the low-viscosity fibre. Plasma cholesterol concentrations, hepatic cholesterol synthesis and faecal bile acid excretion were not altered by dietary fibre viscosity.5. We conclude that the effects of dietary fibre on carbohydrate absorption and storage and fatty acid synthesis are a function of the viscosity of the fibre in solution, high viscosity slowing the digestion and absorption of nutrients in the small intestine. Large-bowel microbial fermentation is not of direct significance to these events. In contrast, effects of fibre polysaccharides on sterol metabolism seem not to be related to their rheological properties.

scholarly journals The availability of zinc in endosperm, whole grain and bran-enriched wheat crispbreads fed to rats on a Zn-deficient diet

1989 ◽  
Vol 62 (1) ◽  
pp. 165-175 ◽  
Author(s):  
Göran Hallmans ◽  
Rolf Sjöström ◽  
Lars Wetter ◽  
Kenneth R. Wing
Keyword(s):  
Wheat Bran ◽  
Dietary Fibre ◽  
Deionized Water ◽  
Male Rats ◽  
Whole Grain ◽  
Deficient Diet ◽  
Growing Rats ◽  
Relative Absorption ◽  
Body Weight Increase ◽  
Wheat Flours

The hypothesis that factors such as dietary fibre and phytate in wheat bran limit the availability of Zn was tested in growing rats fed on low-Zn diets with different wheat crispbreads as the major source of Zn. Six groups of six weanling male rats each were fed on 5 parts semi-synthetic Zn-deficient diet and 1 part wheat-endosperm crispbread for 1 week. At the beginning of the second week, the crispbread in the diet of five groups was exchanged for crispbread made using one of the following wheat flours: (1) whole grain, (2) bran-enriched whole grain, (3) endosperm with Zn added to the whole-grain level, (4) endosperm with Zn added to the bran-enriched level, (5) whole grain with Zn added to the bran-enriched level. These diets were given ad lib. together with deionized water for 2.5 weeks. The relative absorption of Zn was lowest from the three non-supplemented diets (75–82%). All the added Zn was absorbed. As appetite, body-weight increase, Zn absorption, Zn retention and the Zn concentrations in serum and bone differed only slightly among groups fed on diets with similar Zn concentrations, it is concluded that factors such as dietary fibre or phytate in wheat bran limit the availability of Zn in wheat crispbreads very little when all the Zn is needed for growth and development in rats.

scholarly journals An experimental design to study colonic fibre fermentation in the rat: the duration of feeding

1986 ◽  
Vol 55 (3) ◽  
pp. 465-479 ◽  
Author(s):  
Deborah J. Walter ◽  
M. A. Eastwood ◽  
W. G. Brydon ◽  
R. A. Elton
Keyword(s):  
Wheat Bran ◽  
Time Course ◽  
Short Chain Fatty Acid ◽  
Gum Arabic ◽  
Chain Fatty Acid ◽  
The Other ◽  
Diaminopimelic Acid ◽  
Metabolic Adaptation ◽  
Faecal Excretion ◽  
Bacterial Mass

1. The time-course of metabolic adaptation by rats to diets containing either wheat bran or gum arabic was studied during a 12-week period.2. Stool weight was increased with wheat bran but not with gum arabic, and had stabilized after 4 weeks.3. Bacterial mass as measured by diaminopimelic acid content had stabilized by week 4. Bacterial mass increased on feeding gum arabic but was unchanged with wheat bran.4. There was increased caecal short-chain fatty acid, hydrogen and methane production with gum arabic but not with wheat bran. The change in caecal metabolic activity was slow to stabilize (8–12 weeks at least).5. The faecal excretion of bile acids increased twofold with the wheat-bran-supplemented diet compared with the gum-arabic-supplemented and unsupplemented diets. Relatively greater amounts of muricholic acids were present in the caeca and faeces of gum-arabic-fed rats compared with the other groups.

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