Nitric oxide-scavenging and antioxidant effects of Uraria crinita root

The antioxidant activity and the nitric oxide-scavenging effect of methanol extracts (MEUR), and their ethyl acetate fraction (EAF), from Uraria crinita root, were investigated. The results of the comet assay indicated that both MEUR and EAF could inhibit DNA damage in macrophage induced by sodium nitroprusside at a concentration of 25-200 mug/ml. The antioxidant activity of the extracts was determined using the Trolox equivalent antioxidant capacity (TEAC) assay. The TEAC values of MEUR and EAF were 0.2 and 0.4, respectively, at a concentration of 200 mug/ml. The antioxidant activity and nitric oxide-scavenging effect of MEUR and EAF showed concentration-dependence. In addition, the results also showed a decreasing effect on nitric oxide production of lipopolysaccharide-induced RAW 264.7, for both extracts. One of the major antioxidative components was isolated from EAF and was identified as genistein, on the basis of UV-vis spectral, IR, MS and NMR analyses. Thus, the traditional edible plant, Uraria crinita, may have potential as an antioxidant and as a nitric oxide-scavenging agent. (C) 2001 Elsevier Science Ltd. All rights reserved.