We evaluated the antioxidative activity of extracts of P. lobata root depending on roasting conditions. P. lobata roots were roasted at three different temperature at 150℃, 200℃, and 250℃ and three different time at 10 min, 20 min, and 30 min respectively. Roasted P. lobata root was extracted using water at 85℃ for 6 h and filtered using filter paper, followed by then evaporated (12±0.3 °Brix) and freeze-dried. The concentration of maker compound puerarin was determined using a high performance liquid chromatography system. 2 phenolic compounds, flavonoid contents, and antioxidant activities of the extract powder were evaluated. Puerarin contents, Phenolic compounds, and flavonoid contents of roasted P. lobata root were higher than those of unroasted P. lobata root. The results of DPPH and ABTS showed that roasted P. lobata root possessed higher antioxidant activity than unroasted P. lobata root. This study suggested that roasting process could be applied to P. lobata root in order to achieve its high quality and functionality.

Mercuric chloride, inorganic compound, is one of the most important drugs that has been used in the field of argriculture, antisyphilitica and anticeptics, but it is not used clinically at present. We have studied the effect of testosterone on the mercuric chlorideinduced nephrotoxicity. Renal lipid peroxide concentration of male rat treated with mercuric chloride was significantly increased in comparison with that of the female rat, it showed similar effects on testosterone pretreatment. Changes in renal catalase and glutathione peroxidase activities were not siginificantly different in testosterone-treated groups. But, renal xanthine oxidase and aldehyde oxidase activities of testrosterone-treated group given mercuric chloride significantly increased in comparison with that of the testosterone-treated alone. Animals treated with testosterone prior to mercuric chloride showed more severe damage on histological observations than those treated with testosterone only. Consequently, we suggest that the mercuric chloride-induced nephrotoxicity might be renal lipid peroxide generating enzyme system by testosterone.