Inhibition of α-glucosidase activity by ethanolic extract of Melia azedarach L. leaves

Development of α-glucosidase inhibitor derived from natural products is an opportunity for a more economic management of diabetes prevention. The objective of this study was to test the activity of α-glucosidase with or without potential inhibitor compounds. By in vitro method, α-glucosidase hydrolizes p -nitrophenyl-α-D-glucopiranoside to glucose and the yellow of p -nitrophenol which can be determined with spectrophotometry at 400 nm. The ability of ethanolic leaf extract of Melia azedarach L. as a-glucosidase inhibitor was compared with that of commercial acarbose (Glucobay®). Acarbose showed strong inhibitory activity against a-glucosidase with IC 50 values of 2.154 µg/mL. The crude ethanolic leaf extract of M. azedarach, however, showed less inhibitory activity with IC 50 value of 3, 444.114 µg/mL. Total phenolics of M. azedarach leaves EtOH extract showed 17.94 µg GAE/mg extract and flavonoids total compound of 9.55 µg QE/mg extract. Based on the published wide range of IC 50 values of extracts reported as a-glucosidase inhibitor which were between 10, 000 ppm-0.66 ppm, our result suggests that extract of M.azedarach leaves is potential candidate for development of anti-hyperglycemic formulation.