Inhibitory potential of wine and tea against α-amylase and α-glucosidase for management of hyperglycemia linked to type 2 diabetes

Natural alpha-amylase and alpha-glucosidase inhibitors from food-grade plants offer an attractive strategy to manage postprandial hyperglycemia for type 2 diabetes management via control of starch breakdown and intestinal glucose absorption. In this study, four random sources of red and white wines as well as four types of teas were investigated for alpha-amylase and alpha-glucosidase inhibitory potential. Water extracts of black tea had the highest alpha-glucosidase inhibitory activity, followed by white tea and oolong tea. All the randomly selected red wines had significant alpha-glucosidase inhibitory activity compared to white wine. The alpha-glucosidase inhibitory activity of the tea and wines correlated to the phenolic content, antioxidant activity and phenolic profile of the extracts. Further, these extracts had less or no alpha-amylase inhibitory activity, indicating potential to overcome the side effects of undigested starch. This research has relevance for managing hyperglycemia and related oxidation-linked dysfunction and concurrently reducing problems of undigested starch.