In vitro Inhibition of Pancreatic Enzyme Activities by Dietary Fiber

Abstract

Trypsin, amylase, lipase and phospholipase activities were assayed in buffer solutions and in human duodenal juice after incubation with different types of dietary fiber. In buffer solutions, trypsin activity was slightly reduced and amylase activity heavily reduced by pectin of low methylic esterification (LM pectin). Lipase activity was markedly reduced by LM pectin and also moderately reduced by pectin of high methylic esterification (HM pectin). Phospholipase was hardly influenced at all by fiber. Activities of pancreatic enzymes in human duodenal juice were examined after in vitro incubation with pectins, guar gum, wheat bran and ispaghula. Ispaghula did not affect the enzymes except for lipase activity, which was moderately inhibited. The other fiber preparations examined reduced amylase activity by 35–100% at fiber concentrations of up to 1.5 g%, lipase by 40–95% and trypsin by 40–85%. LM pectin had the strongest inhibitory effect among the different fiber preparations studied. Phospholipase activity was only influenced by the pectins, which caused a 75 % reduction. It is concluded that dietary fiber of different kinds has the capacity to inhibit pancreatic enzyme activities. This inhibitory effect is dependent on the type of fiber and differently affects the different enzymes. Further, the inhibition seems to be more pronounced when exerted in human duodenal juice than in conventional buffer systems.

Inhibition of lipase activities by basic polysaccharide

“…Dietary fiber affects lipid metabolism in a variable manner, and some dietary fibers inhibit gastrointestinal lipase reactions, such as pancreatic lipase (1,(22)(23)(24). The effective concentration of these dietary fibers for lipase inhibition is 1-5% (10-50 mg/ml).…”

Interference of Dietary Fibres with Gastrointestinal Enzymes in vitro

“…Hansen [12] has shown that there is a different effect on lipase activity by psyllium (but not by wheat bran or pectin) whether tested in purified form or in duode nal juice. By other authors, differences in enzyme activities dependent on the nature of the solution have also been demonstrated for pectin, wheat bran and guar [16], Viscosity which is dependent on the water-holding property of the fibres may play an important role in the enzyme-dietary fibre interaction varying according to the fibre type, but also to the concentration used [15]. Incubation time is another factor.…”

Steroid Pattern of Bile and Feces in Response to a Fruit-Enriched Diet in Hypercholesterolemic Hamsters

“…Apple components may impair this hydrolysis by reducing the activity of the pancreatic ester ase that catalyzes this reaction. Dietary fi bers have been found to exert an inhibitory effect on the acitivity of this enzyme in duo denal juice taken from human donors [24]. Since the activity of the pancreatic choles terol esterase is bile salt dependent [25], inhibition of cholesterol ester hydrolysis in the gut lumen could be related to a relative unavailability of bile salts which have been sequestered by apple-derived fiber.…”