裸燕麦球蛋白的分离纯化及其抗氧化活性研究

Purification and Antioxidant Activity of Globulins from Naked Oat Seeds

采用Osborne法提取裸燕麦球蛋白,利用盐析、SephadexG-100凝胶过滤层析、SDS-PAGE电泳等方法进一步纯化,并对各球蛋白组分进行抗氧化能力的研究。结果表明:裸燕麦球蛋白的硫酸铵饱和度为60%。在柱层析分离条件下(洗脱速度为3～7mL/10min,缓冲溶液为蒸馏水),得到的组分I分子质量范围分布在44、34～29、25kD,组分II分子质量范围分布在25、23、19kD。组分I清除3种自由基的作用较强,清除.O H、O2.、DPPH自由基的IC50分别为3.73、0.016、1.033mg/mL,其中对O2.清除能力大于VC对O2.的清除能力。组分II清除3种自由基能力均低于分离组分I、盐析后球蛋白和球蛋白粗提物。

A crude globulin extract from naked oat seeds was prepared by Osborne method and purified by salting-out and Sephadex G-100 gel filtration chromatography,and the crude extract was separated into two fractions（I and II）.The crude globulin extract,its salting-out purification product and fractions I and II were subjected to SDS-PAGE analysis and antioxidant activity evaluation.Oat seed globulins exhibited 60% degree of saturation with ammonium sulphate.The molecular weight distribution of fraction I consisted of 44,34-29kD and25 kD,and that of fraction I was 25,23,19 kD.Among the four materials,fraction I had the strongest scavenging effect on hydroxyl,superoxide anion and DPPH free radicals,with IC50 values of 3.73,0.016 mg/mL and 1.033 mg/mL,respectively,and its hydroxyl free radical scavenging effect was higher than that of VC.However,the free radical scavenging effect of fraction II was lower than those of all three other materials.