Characteristic hydrolyzing of megalosaccharide by human salivary alpha-amylase and small intestinal enzymes, and its bioavailability in healthy subjects

摘要

The digestibility of Megalosaccharide (R) (newly developed carbohydrate comprising alpha-1,4-glucosaccharide) was investigated in vitro and in vivo. Isomaltosyl-megalosaccharide (R) (IMS) and nigerosyl-megalosaccharide (R) (NMS) contain 20% and 50% of the megalosaccharide fraction (degree of polymerization (DP) 10-35), respectively. IMS was hydrolyzed readily by alpha-amylase to oligosaccharides (DP <= 7), and a small amount of glucose was produced from oligosaccharides by small intestinal enzymes (SIEs). NMS was partially hydrolyzed by alpha-amylase to oligosaccharides, and a small amount of glucose produced by SIEs. When IMS and NMS were treated by SIEs after treatment with human saliva alpha-amylase for a few minutes, IMS and NMS were hydrolyzed readily to glucose. Plasma levels of glucose and insulin upon ingestion of 50 g of IMS or NMS were elevated the same as those for 50 g of glucose, and breath hydrogen was not excreted. These results suggest that IMS and NMS are digestible carbohydrates.