flavonoids from salvia chloroleuca with α-amylsae and α-glucosidase inhibitory effect

it is believed that the inhibition of carbohydrate hydrolyzing enzymes including α-amylase and α-glucosidase is one of the therapeutic approaches to decrease the postprandial glucose level after a meal, especially in the people with type 2 diabetes. medicinal plants and their extracts are one of the main sources to find new inhibitors to the enzymes. in our study four flavonoids, namely luteolin 7-o-glucoside (1), luteolin 7-o-glucuronide (2), diosmetin 7-o-glucuronide (3) and salvigenin (4) were isolated from aerial parts of salvia chloroleuca. the inhibitory activity of these compounds against α-amylase and α-glucosidase were evaluated. compounds 1, 2 and 3 showed potent α-glucosidase inhibitory effect with ic50 values of 18.3, 14.7, and 17.1 µm, respectively. also these compounds exhibited moderate α-amylase activity with ic50 values 81.7, 61.5, and 76.3 µm, respectively.