Ousmane Faye¹, Cheikh Sall^1,, Mamadou Soumboundou¹, Awa Ndong^{1, 2}, Mathilde Cabral², Guata Yoro Sy³, Fatou Bintou Sar¹

Secondary metabolites of medicinal plants constitute a real alternative treatment for diabetes mellitus. They are also sources of natural compounds that could lead to the discovery of new drugs. In this study, the anti-amylase and antioxidant activities of alkaloids and flavonoids extracted from Mitracarpus hirtus leaves were evaluated. DPPH radical and DNS inhibition methods were used for antioxidant activity and anti α-amylase activity, respectively. The results obtained showed that di- and tri-glycoside flavonoids and monoglycosides are the most present with contents of 796 and 522 mg RQE/gES while alkaloids are present at 203 mg RQQ/gES. The DPPH radical inhibitory activity test gives IC₅₀ of 187.99; 236 ug/ml for the di and tri glycosides and monoglycosides flavonoids respectively. Alkaloids show IC₅₀ of 815ug/ml and ascorbic acid used as reference has IC₅₀ of 110 ug/ml. The result of the anti α-amylase activity shows that the monoglycoside flavonoids are more active with an IC₅₀ of 74 ug/ml while the alkaloids have an IC₅₀ of 228 ug/ml. We note that in all the studied parameters, flavonoids are more active than alkaloids. However, the activity of flavonoids is not polarity dependent. The fractions rich in flavonoid mono, di and tri glycosides present rather interesting activities and deserve to be tested in vivo in order to propose them as an alternative treatment for diabetes mellitus.

diabetes, Mitracarpus hirtus, alkaloids, flavonoids