蒜头果种子中水溶性蛋白的提取及其抗氧化性

Study on isolation and antioxidant activity of water-soluble protein from Malania oleifera seeds

采用饱和（NH4）2SO4法对蒜头果种子中水溶性蛋白进行逐级分离,并测定其体外抗氧化活性。结果表明：60%~80%饱和度的（NH4）2SO4对蒜头果种子中水溶性蛋白的分离效果最好,同时各级盐析蛋白组分均对超氧阴离子（O2-·）、二苯代苦味酰基自由基（DPPH·）和羟自由基（·OH）有不同程度的清除能力,其中以40%~60%、60%~80%和80%~100%3个（NH4）2SO4饱和度段的效果最为明显。结合十二烷基磺酸钠-聚丙烯酰胺凝胶电泳（SDS-PAGE）图谱分析,分子质量为30.0 kDa和60.0 kDa左右的2种蛋白可能在蒜头果种子水溶性蛋白的抗氧化反应中发挥着重要作用。

The water-soluble proteins were isolated from Malania oleifera seeds by the process of ammonium sul- fate salting-out, and the antioxidant activities with different concentration of ammonium sulfate precipitation were de- termined in vitro. The results showed that isolation with 60% - 80% concentration of ammonium sulfate was the best. All levels of protein components salting by ammonium sulfate precipitation showed significant scavenging capacity on O2 -· , DPPH - and - OH, and the isolation with 40% -60% ,60% -80% ,80% - 100% concentration of ammo- nium sulfate was most obvious. It indicated that the water-soluble proteins from Malania oleifera seeds with 30.0kDa and -60.0kDa molecular weight may play an important role in anti-oxidation reactions combined with SDS- PAGE result.