Optimization of in vitro carbohydrate digestion by mammalian mucosal α-glucosidases and its applications to hydrolyze the various sources of starches

Abstract

Glycemic carbohydrates, such as starch and sucrose, are fully hydrolyzed into monosaccharides by mucosal α-glucosidases in the small intestine. In this study, we optimized the reaction conditions of mammalian mucosal α-glucosidases to digest various types of glycemic carbohydrates to determine their hydrolytic activity. The results clearly showed that mammalian mucosal α-glucosidases had different hydrolytic properties compared to fungal amyloglucosidase, which is commonly used in vitro assay to determine carbohydrate quality, on various sizes and α-linked carbohydrates. Furthermore, non-gelatinized and gelatinized starches from different botanical sources were differently hydrolyzed to glucose by the prepared solution of mammalian α-glucosidases and porcine pancreatic α-amylase. Thus, it is clearly suggested that the digestion of glycemic carbohydrates by the optimized reaction condition with mammalian mucosal α-glucosidases and pancreatic α-amylase can be applied to determine the carbohydrate quality and digestion properties as it is more reliable to human digestive enzymes compared to fungal or microbial α-glucosidases.