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Effect of oat gum on the physical properties of the gastrointestinal contents and on the uptake of D-galactose and cholesterol by rat small intestine in vitro

Published online by Cambridge University Press:  09 March 2007

E. K. Lund
Affiliation:
AFRC Institute of Food Research, Norwich Laboratory, Colney Lane, Norwich NR4 7UA
J. M. Gee
Affiliation:
AFRC Institute of Food Research, Norwich Laboratory, Colney Lane, Norwich NR4 7UA
J. C. Brown
Affiliation:
AFRC Institute of Food Research, Norwich Laboratory, Colney Lane, Norwich NR4 7UA
P. J. Wood
Affiliation:
AFRC Institute of Food Research, Norwich Laboratory, Colney Lane, Norwich NR4 7UA
I. T. Johnson
Affiliation:
AFRC Institute of Food Research, Norwich Laboratory, Colney Lane, Norwich NR4 7UA
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Abstract

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Recent reports indicate that oats have a relatively low glycaemic effect in comparison with other carbohydrate food, and that their consumption leads to a reduction in plasma-cholesterol levels in man. These properties may be due to a soluble non-starch polysaccharide in oats. The present study was undertaken to explore the physiological properties of this material. Three groups of male Wistar rats were meal-fed on a control diet free of soluble dietary fibre for 10 d before being given a 10 g meal of either the control diet, a diet containing oat gum (β-glucan), or finely ground rolled oats. The contents of the stomach, small intestine and caecum were later recovered and the weight, water content and viscosity were measured. The small intestinal contents from oat-gum-fed or oat-fed rats had a higher wet: dry weight ratio than that of the controls, and a higher viscosity. In in vitro studies the rate of uptake of d-galactose by jejunal rings was reduced in the presence of oat gum. The estimated Michaelis-Menten constant for the carrier-mediated component in the presence of oat gum was higher than that for controls, but the maximum transport rates were similar. Cholesterol uptake by everted jejunal sacs was progressively inhibited by increasing concentrations of oat gum in the mucosal medium. It is concluded that increased viscosity of the contents of the small intestine may contribute to the low glycaemic index and hypocholesterolaemic effects of oats in man. Oats appear to be amongst the few palatable sources of viscous dietary fibre in the conventional Western diet.

Type
Research Article
Copyright
Copyright © The Nutrition Society 1989

References

REFERENCES

Anderson, J.W. & Bridges, S.R. (1981). Plant fibre metabolites alter hepatic glucose and lipid metabolism. Diabetes 30, 133A.Google Scholar
Apling, E.C. & Ellis, P.R. (1982). Guar bread: concept to application. Chemistry and Industry 950954.Google Scholar
Blackburn, N.A. & Johnson, I.T. (1981). The effect of guar gum on the viscosity of the gastrointestinal contents and on glucose uptake from the perfused jejunum in the rat. British Journal of Nutrition 46, 239246.CrossRefGoogle ScholarPubMed
Blackburn, N.A. & Johnson, I.T. (1983). The influence of guar gum on the movements of inulin, glucose and fluid in rat intestine during perfusion. Plügers Archiv 397, 144148.CrossRefGoogle ScholarPubMed
Blackburn, N.A., Redfern, J.S., Jarjis, H., Holgate, A.M., Hanning, I., Scarpello, J.H.B., Johnson, I.T. & Read, N.W. (1984). The mechanism of action of guar gum in improving glucose tolerance in man. Clinical Science 66, 329366.CrossRefGoogle ScholarPubMed
Brown, N.J., Worldling, J., Rumsey, R.D.E. & Read, N.W. (1988). The effect of guar gum on the distribution of the radiolabelled meal in the gastrointestinal tract. British Journal of Nutrition 59, 223231.CrossRefGoogle ScholarPubMed
Chow, S.L. & Hollander, D. (1978). Initial cholesterol uptake by everted sacs of rat small intestine: kinetic and thermodynamic aspects. Lipids 13, 239245.CrossRefGoogle ScholarPubMed
De Groot, A.P., Luyken, R. & Pikaar, N.A. (1963). Cholesterol-lowering effect of rolled oats. Lancet ii, 203204.Google Scholar
Diamond, J. (1966). A rapid method for determining voltage concentration relations across membranes. Journal of Physiology 183, 83100.CrossRefGoogle ScholarPubMed
Duggleby, R.G. (1981). A non-linear regression programme for small computers. Analytical Biochemistry 110, 918.CrossRefGoogle Scholar
Edwards, C.A., Johnson, I.T. & Read, N.W. (1988). Do viscous polysaccharides slow absorption by inhibiting diffusion or convection? European Journal of Clinical Nutrition 42, 307312.Google ScholarPubMed
Gee, J.M., Blackburn, N.A. & Johnson, I.T. (1983). The influence of guar gum on intestinal cholesterol transport in the rat. British Journal of Nutrition 50, 215224.CrossRefGoogle ScholarPubMed
Gee, J.M. & Johnson, I.T. (1985). Rates of starch hydrolysis and changes in viscosity in a range of common foods subjected to simulated digestion in vitro. Journal of the Science of Food and Agriculture 36, 614620.CrossRefGoogle Scholar
Gold, K.V. & Davidson, D.M. (1988). Oat bran as a cholesterol-reducing dietary adjunct in a young, healthy population. Western Journal of Medicine 148, 299302.Google Scholar
Heaton, K.W., Marcus, S.N., Emmett, P.M. & Bolton, C.H. (1988). Particle size of wheat, maize, and oat test meals: effects on plasma glucose and insulin responses and on the rate of starch digestion in vitro. American Journal of Clinical Nutrition 47, 675682.CrossRefGoogle ScholarPubMed
Horn, N., Wyatt, G.M., Bayliss, C.E., Gee, J.M. & Johnson, I.T. (1986). The effect of dietary fibres on bacterial densities in the rat intestine. Food Microbiology 3, 295302.CrossRefGoogle Scholar
Jenkins, D.J.A., Ghafari, H., Wolever,, T.M.S., Taylor, R.H., Barker, H.M., Fielden, H. & Bowling, A.C. (1982). Relationship between rate of digestion of foods and post-prandial glycaemia. Diabetologia 22, 450455.CrossRefGoogle ScholarPubMed
Jenkins, D.J.A., Wolever,, T.M.S., Leeds, A.R., Gassull, M.A., Haisman, P., Dilawari, J., Goff, D.V., Metz, G.L. & Alberti, K.G.M.M. (1978). Dietary fibres, fibre analogues and glucose tolerance: importance of viscosity. British Medical Journal i, 13921394.CrossRefGoogle Scholar
Johnson, I.T. & Gee, J.M. (1981). Effect of gel-forming gums on the intestinal unstirred layer and sugar transport in vitro. Gut 22, 398403.CrossRefGoogle ScholarPubMed
Judd, P.A. & Truswell, A.S. (1981). The effect of rolled oats on blood lipids and fecal steroid excretion in man. American Journal of Clinical Nutrition 34, 20612067.CrossRefGoogle ScholarPubMed
Phillips, D.R. (1986). The effect of guar gum in solution on diffusion of cholesterol mixed micelles. Journal of the Science of Food and Agriculture 37, 548552.CrossRefGoogle Scholar
Pollay, M., Stevens, A. & Kaplan, R. (1969). Diffusion of radioactive non-electrolytes in saline-agar gels. Analytical Biochemistry 27, 381386.CrossRefGoogle Scholar
Rainbird, A.L., Low, A.G. & Zebrowska, T. (1984). Effect of guar gum on glucose and water absorption from isolated loops in conscious growing pigs. British Journal of Nutrition 52, 489498.CrossRefGoogle ScholarPubMed
Simpson, H.C.R., Lousley, S., Geekie, M., Simpson, R.W., Carter, R.D., Hockaday, T.D.R. & Mann, J.I. (1981). A high carbohydrate leguminous fibre diet improves all aspects of diabetic control. Lancet i, 15.CrossRefGoogle Scholar
Storch, K., Anderson, J.W. & Young, V.R. (1984). Oat bran muffins lower serum cholesterol of healthy young people. Clinical Research 32, 740A.Google Scholar
Thomson, A.B.R. & Dietschy, J.M. (1977). Derivation of the equations that describe the effects of unstirred water layers on the kinetic parameters of active transport processes in the intestine. Journal of Theoretical Biology 64, 277294.CrossRefGoogle ScholarPubMed
Trout, D.L., Ryan, R.O. & Bickard, M.C. (1983). The amount and distribution of water, dry matter and sugars in the digestive tract of rats fed xanthan gum (41567). Proceedings of the Society for Experimental Biology and Medicine 172, 340345.CrossRefGoogle Scholar
Van Horn, L.V., Liu, K., Parker, D., Emidy, L., Liao, Y., Pan, W.H., Giumetti, D., Hewitt, J. & Stamler, J. (1986). Serum lipid response to oat product intake with a fat-modified diet. Journal of the American Dietetic Association 86, 759764.CrossRefGoogle ScholarPubMed
Wood, P.J. (1986). Oat β-glucan: structure, location, and properties. In Oats Chemistry and Technology, pp. 121–152 [Webster, F.H., editor]. St Paul, Minnesota: American Association of Cereal Chemists.Google Scholar
Wood, P.J., Siddiqui, I.R. & Paton, D. (1978). Extraction of high-viscosity gums from oats. Cereal Chemistry 55, 10381049.Google Scholar