Identification of α-Glucosidase Inhibitors From Psidium guajava Leaves and Syzygium cumini Linn. Seeds

We screened for α-glucosidase inhibitors from 12 traditional medicinal plants used for the treatment of diabetes. Potent α-glucosidase inhibitory activity was found in aqueous extract of Psidium guajava leaves and Syzygium cumini Linn seed extract. Active principles inhibiting α-glucosidase were isolated and identified as apigenin 7- O-glucoside in the S.cumini Linn seed extract and Dihydro-3,3’,4’,5,7 – pentahydroxyflavone glycoside in P.guajava leaf extract through FT-IR and LC-MS. The inhibitor present in both P.guajava leaves and S.cumini Linn seed extract was found to be reversible in nature.