In vitro antioxidant and ?-glucosidase inhibitory activities of aqueous extract and ethyl acetate fraction of hallea stipulosa (rubiaceae)

Poualeu Kamani Sylviane Laure1*, Wansi Sylvie Lea1, Chouna Jean Rodolphe2, Miaffo David1,3, Nkeng-Efouet Pepin Alango2, Kamanyi Albert1

Antioxidant potential of plants is useful in the management of diabetes mellitus. Aim of this study was to determine the in vitro antioxidant and α-glucosidase inhibitory activities of aqueous extract and ethyl acetate fraction of Hallea stipulosa. In vitro antioxidant assays were used DPPH (1,1-Diphenyl-2-Picrylhydrazyl) scavenging assay, nitric oxide (NO) inhibition assay, ferric reducing antioxidant power (FRAP), determination of total phenol and flavonoid contents. Aqueous extract and ethyl acetate fraction exhibited a scavenging activity by inhibiting DPPH and NO radicals and showed good reducing power capability. They contain a significant amount of phenols and flavonoids. Ethyl acetate fraction showed a considerable α-glucosidase inhibitory activity with an IC50 of 39.19 μg/ml. Results suggest that antioxidant potential and α-glucosidase inhibitory activity of H. stipulosa could be due to phenols and flavonoids and could be a part of the mechanism by which it manages diabetes.