聚丙烯酰胺凝胶电泳法快速检测植物源性食品中的蛋白成分

Rapid detection of proteins in plant-derived foods by sodium dodecyl sulfate polyacrylamide gel electrophoresis

目的建立十二烷基磺酸钠-聚丙烯酰胺凝胶电泳法(sodium dodecyl sulfate polyacrylamide gel electrophoresis,SDS-PAGE)鉴定核桃、杏仁、花生、大豆中的蛋白成分,并分析植物蛋白饮料中蛋白质的来源。方法采用一步法植物活性蛋白质提取试剂盒分别提取预处理后的核桃、杏仁、花生、大豆等样品中的蛋白质成分,计算蛋白质的相对分子量,之后分别进行SDS-PAGE检测得到这几种蛋白成分的特征条带,并对不同样品中蛋白成分的电泳图谱进行比对。结果每一物种都有相对应的蛋白指纹图谱,不同种类的核桃含有相同的蛋白质亚基,具有高同源性,但核桃与花生、黄豆和杏仁含有不同种类大小的蛋白,具有高特异性。结论本方法快速、准确、灵敏,可有效分析植物蛋白饮料中各类蛋白质的来源,对食品中植物源性成分的鉴定具有重要意义。

Objective To establish a method for identification of proteins from walnuts,almonds,peanuts and soybeans by sodium dodecyl sulfate polyacrylamide gel electrophoresis（SDS-PAGE）.Methods Using one-step plant protein extraction kit to extract proteins from pretreatmented walnut,almond,peanut and soybean,the relative molecular weights of proteins were calculated,SDS-PAGE was used to obtain the characteristic bands of different proteins,and then their electrophoretograms were compared.Results Each species had corresponding protein fingerprints,different kinds of walnuts contained the same protein subunits with higher homology.Walnuts contained different protein subunits in contrast with almonds,peanuts and soybeans,which had strong specificity.Conclusion The method is rapid,accurate and sensitive,which can effectively analyze the protein source in plant-based beverages,and this method is important for identification of plant-derived constituents in foods.