Abstract

The antioxidant activities in vitro and in vivo assays of the four extracts from the herb ofAstragalus were investigated. 2,2′-azino-bis-3-ethylbenzthiazoline-6-sulphonic acid (ABTS) and 1,1-diphenyl-2-picrylhydrazyl (DPPH) and reducing power assays were used to evaluate the antioxidant activities of the extracts in vitro. The effect of ethyl acetate extracts (EAE) in reducing oxidative stress in mice was evaluated. From the results of antioxidant assays in vitro, EAE was found to have the highest antioxidant activity. The antioxidant assay results showed that high doses of EAE significantly decrease the MDA level and increase the SOD activity of mice in vivo. These studies in vitro and in vivo demonstrated that the extract EAE fromAstragalus has significant antioxidant and free radical scavenging activities. In summary, the results exhibited that the Astragalus could be used as a rich source of potentially natural antioxidants.

Key words: Astragalus, free radical, antioxidant activity.