酪蛋白非磷肽Na2SeO3的制备、表征及总抗氧化能力的测定

Preparation,characterization and determination of total antioxidant capacity of casein non-phosphopeptides Na_2SeO_3

为探究酪蛋白非磷肽Na2SeO3的表面及其总抗氧化能力(TEAC)的特性,以酪蛋白为原料,选用碱性蛋白酶(Alcalase)对其进行水解,分离提取出酪蛋白非磷肽和酪蛋白磷酸肽,然后与Na2SeO3反应。通过氢化物原子荧光光谱法(HG-AFS)对酪蛋白非磷肽和酪蛋白磷酸肽与Na2SeO3的反应产物进行检测,结果表明,酪蛋白非磷肽与Na2SeO3反应产生的酪蛋白非磷肽Na2SeO3是富含硒元素的红色物质。采用透射电镜(TEM)测试酪蛋白非磷肽Na2SeO3的表面结构,得出该物质多为纳米级的颗粒物。同时采用总抗氧化能力测试法(ABTS)测试分析不同反应产物TEAC的变化,结果显示,不同反应物与Na2SeO3结合后其抗氧化能力都有所提升,且酪蛋白非磷肽Na2SeO3总抗氧化能力的提升最为显著。

The surface properties and total antioxidant capacity（TEAC） of Casein non-phosphopeptides Na2SeO3 were discussed. Casein was hydrolyzed by Alkaline Protease （Alcalase） and then separated into Casein non-phos- phopeptides and Casein phosphopeptides and reacted with Na2SeO3. Hydride Generation Atomic Fluorescence Spec- trometry （HG-AFS） was utilized to test Casein non-phosphopeptides, Casein phosphopeptides and Na2SeO3. The re- sult showed that Casein non-phosphopeptides NaESeO3 was selenium-rich red substance. After analyzed by High Reso- lution Transmission Electron Microscope （TEM） , the most red substances were identified as nanoscale particles. At the same time, the changes of Trolox-Equivalent Antioxidant Capacity（TEAC）in different reactions were measured by ABTS method. Results showed that antioxidant capacity were all enhanced after Na2SeO3 reaction. Among them, TE- AC of Casein non-phosphopeptides Na2SeO3 was improved most significantly.