Daidzein inhibits carbohydrate digestive enzymes in vitro and alleviates postprandial hyperglycemia in diabetic mice

This study was designed to investigate whether daidzein inhibits alpha-glucosidase and alpha-amylase activities and alleviates postprandial hyperglycemia in streptozotocin-induced diabetic mice. Daidzein showed prominent inhibitory effects against alpha-glucosidase and alpha-amylase. The IC50 values of daidzein against alpha-glucosidase and alpha-amylase were 0.048 and 0.301 mmol, respectively, which showed that daidzein was more effective than acarbose. The increase in postprandial blood glucose levels was more significantly suppressed in the daidzein-administered group than in the water group of both streptozotocin-induced diabetic and normal mice. Moreover, the area under the curve was significantly lowered following daidzein administration (2043 versus 2475 mmol min l) in the streptozotocin-induced diabetic mice. These results indicated that daidzein may be a potent alpha-glucosidase inhibitor and suppress the postprandial hyperglycemia caused by starch. (C) 2013 Elsevier B.V. All rights reserved.