The crude methanolic extract of Bacopa monnieri was studied to evaluate its antioxidant activity by six in vitro methods. The extract was found to contain significant amount of phenol and flavonoid in Folin-Ciocalteau and total flavonoid content assay. Total antioxidant capacity of the extract was estimated to be 261.16 mg/g of ascorbic acid equivalent. Its IC50 value in DPPH method was 456.07 Hg/mL. The extract showed concomitant increase in reducing power with the increase of concentration of the extract. IC50 value in NO scavenging activity of the extract was 21.29 pig/mL whereas ascorbic acid and quercetin showed the values of 5.47fig/mL 15.24fig/ml, respectively.
Keywords: Bacopa monnieri, Antioxidant, DPPH, Reducing power, Nitric oxide.