摘要
从玉米胚芽提取得到的SOD粗酶液,经硫酸铵分级沉淀、DE-52纤维素柱层析和Sephadex G-75层析法分离纯化,得到纯的玉米SOD,比活为3 583.3 U/mg蛋白,纯化倍数为61.4.经鉴定,玉米SOD为Cu,Zn-SOD,Cu和Zn离子含量之比约为1∶5,在260nm处有最大吸收峰.用SDS-PAGE测得SOD亚基分子量为18 800,玉米SOD分子量为37 600.实验表明,玉米SOD在50℃以下热稳定性较好,在pH 7～8较稳定.
The superoxide dismutase （SOD） extracted from corn germ was separated and purified by ammonium sulfate precipitation, DE-52 cellulose ion chromatography and Sephadex G- 75 gel filtration chromatography. The specific activities of the purified SOD reach 3,583.3 U/rag protein and the degree of the purification is 61.4 -fold. The purified SOD is characterized as Cu, Zn- SOD in which the Cu- to- Zn ratio is about 1：5, and its maximum absorption in ultraviolet is at 260nm. The molecule weight of the SOD is 37,600, which is consisted of two subunits with a molecular weight of 18,800 determined through SDS - PAGE. Finally, it is indicated that the SOD is more stable under temperature 50℃ and in pH 7 -8.
出处
《中国粮油学报》
EI
CAS
CSCD
北大核心
2006年第4期40-44,共5页
Journal of the Chinese Cereals and Oils Association
关键词
玉米
超氧化物歧化酶
纯化
性质
corn, superoxide dismutase, purification, characterization
