Important therapeutic approaches available for managing early stages of type 2 diabetes are by controlling the absorption of glucose through the reduction of starch hydrolysis, by inhibiting pancreatic α-amylase and limiting the breakdown and absorption of glucose and by inhibiting intestinal α-glucosidase. Many in vitro studies have been reported that phenolic metabolites including flavonoids (anthocyanins, catechins, flavanones, flavonols, flavones and isoflavones), phenolic acids and
tanins (proanthocyanidinins and ellagitannins) inhibit α-amylase and α-glucosidase