Separation,purification and properties of superoxide dismutase from germination of mung bean

The different periods of germination of mung bean was used to prepare the crude SOD enzyme extract,and the highest specific activity during the period of crude enzyme solution was screened,then the solution was separated and purified by the thermal denaturation,ammonium sulfate fractionation,DEAE-Sepharose FF anion-exchange chromatography and SephacrylS 100 molecular sieve chromatography,finally the physical and chemical properties of the pure SOD enzyme were studied.The results showed the maximum specific activity of SOD on the seed germination 3 days of mung bean,and the purified SOD enzyme specific activity was 2256.4 U/mg(purification factor 3.9).As the structure of SOD in Mung bean,Cu/Zn SOD and MnSOD have a molecular weight of 68KD,high thermal stability,stability in the pH 5-8,and resistant to high concentrations of SDS,and its activity was able to inhibited by EDTA and completely inhibited by H2O2.