Sucrase Inhibitory Activity of D-Xylose and Effect on the Elevation of Blood Glucose in Rats

Abstract

The inhibitory action of D-xylose on sucrase activity in vitro and its effects on elevation of blood glucose after oral administration of sucrose in vivo were examined. D-Xylose inhibited rat-intestinal sucrase activity as an uncompetitive inhibitor. This saccharide also inhibited maltase activity, but its inhibitory activity was weaker than that of a sucrase inhibitor. Among various saccharides, L-arabinose, D-ribose and D-glucurono-6.3-lactone produced inhibition to a similar extent. D-Xylose reduced the absorption of sucrose from a ligated loop in the upper portion of the rat small intestine in situ. In fact, it suppressed the intensive elevation of blood glucose and insulin levels after oral administration of sucrose in rats, and showed a similar tendency in human volunteers.