Phytochemical Screening, Polyphenolic Content and Alpha-Glucosidase Inhibitory Potential of Leptadenia hastata (Pers.) Decne

Leptadenia hastata (Pers.) Decne. (Asclepiadaceae) is widely used as vegetable and traditionally in the management of diabetes mellitus and in the treatment of wounds and stomach ache. In this study, phytochemical screening, total phenolic contents and alpha-glucosidase activity of L. hastata leaf extracts were evaluated with the view to validating its antidiabetic potentials. Acetone, methanol and water extracts were screened for the polyphenolic contents while methanol and water extract were used for the evaluation of alpha-glucosidase activity. Phytochemical screening of L. hastata leaf indicated the presence of phenolic glycosides, tannins, flavonoids, proanthocyanidins, alkaloids and saponins. The total phenolics, total flavonoids and proanthocyanidins contents were in the ranges of 17-38, 10-16 and 4-10 mg/g respectively depending on the extraction solvent. The methanol and water extracts had 69.81 and 37.02 % inhibitory effect on alpha-glucosidase activity respectively. The results indicated that L. hastata leaf is rich in polyphenols and possess significant alpha-glucosidase inhibition potential and may therefore be a source of lead compounds in the management of diabetes mellitus and/or other diseases that may be caused by oxidative stress.Keywords: Leptadenia hastata, phytochemicals, polyphenols, alpha-glucosidase, effect, inhibitionNigerian Journal of Basic and Applied Science (2011), 19 (2): 181-18