AJP - Gastrointestinal and Liver Physiology, Vol 250, Issue 4 420-G426, Copyright © 1986 by American Physiological Society
Intestinal interaction of bile acids, phospholipids, dietary fibers, and cholestyramine
D. Gallaher and B. O. Schneeman
Binding of bile acids and phospholipids to a number of dietary fibers and
cholestyramine (CH) within the small intestine was determined. The fibers
used were cellulose, wheat bran, oat bran, guar gum (GG), and lignin (LG).
GG, LG, and CH bound significant quantities of bile acids. However, only
the CH reduced the bile acid concentration within the aqueous phase of the
intestinal contents. Significant phospholipid binding was found only with
CH. None of the test substances significantly reduced the quantity of
solubilized lipid. Multiple regression analysis indicated that the total
quantity of bile acids and phospholipids in the aqueous phase of the
intestinal contents was a significant predictor of the quantity of lipid
solubilized within the contents (r2 = 0.67). The failure of GG and LG to
significantly decrease the amount of solubilized lipid suggests that the
hypocholesterolemic effect of these fibers is due more to their bile acid
binding capacity than to an effect on lipid solubilization.
