Abstract:Cupper and zinc-containing superoxide dismutase from broad beau(Vicia faba) seeds was purified to homogeneity by the steps of crude extract, chloroform-ethanol treatment, aceton precipitation, DEAE-cellulose chromatography and Sepharose 6B chromatography. The purified enzyme had a specific activity of 2852 units mg-1 protein. Its activity was strongly inhibited by KCN and H2O2. Its molecular weight and subunit molecular weight were 31000 and 14400 respectively, which indicated that the enzyme was composed of two identical subunits. The enzyme was stable to heat below 70 ℃ and to pH at range of 5 -9, and exhibited maximum ultraviolet absorption at 273.5um.