Abstract

Seabuckthorn (Hippophae rhamnoides L.) is thorny nitrogen fixing deciduous shrub native to Asia and Europe. The present study was undertaken to evaluate the antidiabetic and antioxidant effect of two different extracts, namely, methanolic and aqueous of seabuckthorn (H. rhamnoides L.) leaves by in vitro assays. Seabuckthorn leaves were procured from Lahul area of H.P. Leaves were dried and subjected to methanolic and aqueous extraction. Antidiabetic activity was measured by alpha-glucosidase inhibitor assay. Antioxidant activity was studied by measuring the total antioxidant activity by 2,2-diphenyl-1-picrylhydrazyl) radical scavenging activity (DPPH) free radical scavenging assay and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) method. IC₅₀ values of both extracts were calculated for all the assays. The results showed that methanolic extract of seabuckthorn leaves have the potential to inhibit alpha glucosidase with IC₅₀ value of 0.25 mg/ml. Similar to antidiabetic effect, methanolic extract also exhibited better antioxidant activity as compared to aqueous extract. Therefore, it is suggested that methanolic extract of seabuckthorn leaves is a potential source for natural antidiabetic and antioxidant compounds and could have potential use in the management of diabetes mellitus.

Key words: Hippophae rhamnoides, seabuckthorn, alpha glucosidase, antidiabetic, antioxidant.