体积排阻色谱-电感耦合等离子体质谱分析富硒大米含硒蛋白组成

Analysis of Component Se-containing Proteins in Se-enriched Rice Using Size Exclusion Chromatography-Inductively Coupled Plasma Mass Spectrometry

建立体积排阻色谱-电感耦合等离子体质谱(SEC-HPLC-ICP-MS)联用技术分析富硒大米含硒蛋白组成方法。通过水提、盐提、碱提和醇提方法提取,并用丙酮沉淀蛋白,硒的回收率分别为9.6%,16.8%,48.2%和14.9%,纯化后的蛋白结合硒的量由大到小依次为碱溶谷蛋白>球蛋白>醇溶蛋白>清蛋白。蛋白液经SEC-HPLC-ICP-MS检测,通过蛋白色谱峰(λ=280 nm)和ICP-MS硒峰(78Se)对比分析,利用分子量标准曲线测定出4类蛋白中含硒蛋白的分子量。结果表明,富硒大米中清蛋白和醇溶蛋白并不是硒的主要存在蛋白。硒主要存在于>7 kDa的碱溶谷蛋白和球蛋白,其中碱溶含硒蛋白主要组分F1分子量为199.8 kDa。

The component Se-containing proteins in Se-enriched rice were investigated using size exclusion chromatography-high performance liquid chromatography coupled with inductively coupled plasma mass spectrometry（SEC-HPLC-ICP-MS）.The selenium recoveries of water extraction,NaCl extraction,NaOH extraction and EtOH extraction after rice protein precipitation were 9.6%,16.8%,48.2% and 14.9%,respectively.The amount of purified protein binding Se was as following order： glutelinglobulinalbuminprolamin.When the protein solutions were injected to SEC-HPLC-ICP-MS,with comparison of protein peaks（λ=280 nm） and Se peaks（78Se）,the molecular weights of four proteins were determined by molecular weight curves.The results showed that Se was mainly incorporated into glutelin and globulin higher than 7 kDa,while albumin and prolamin were not the most protein binding Se in Se-enriched rice.The molecular weight of major fraction F1 in glutelin was 199.8 kDa.