大豆蛋白饮料中大豆蛋白定量方法研究

Research on Quantitation of Soybean Protein in Soybean Protein Beverage

[目的]建立基于竞争酶联免疫分析（ELISA）的大豆蛋白饮料中大豆蛋白定量方法。[方法]以变性的大豆球蛋白和β-伴球蛋白为抗原,分别制备抗这2种蛋白的多克隆抗体,构建竞争ELISA方法。分析了9个品系的大豆球蛋白、β-伴球蛋白、可溶蛋白的含量。基于大豆球蛋白与伴球蛋白含量之和与可溶蛋白的比例关系,得出了植物蛋白饮料中大豆蛋白含量的计算方法。[结果]该方法的线性范围均为2.0-80μg/ml（R^2=0.99）,样品前处理使用含有0.1%二硫苏糖醇（DTT）的7 mol/L尿素作为提取液。大豆球蛋白与伴球蛋白含量之和除以系数0.682可换算得到蛋白饮料中大豆蛋白含量,方法的相对标准偏差〈12%。[结论]研究可为其他热加工食品的蛋白特异性定量提供参考。

Abstract [ Objective ] The aim of the research was to develop competitive enzyme linked immunosorbent assay （ELISA） for quantitation of soybean protein in soybean protein beverage. [ Method ] Denatured glycinin and β-conglycinin were used as antigen respectively to prepare polyclonal antibody and establish competitive ELISA. Glycinin, 13-conglycinin and soluble protein content in soybean of 9 strains was detected. Based on the proportionate relationship between the soluble protein content and the total content of glycinin and β-conglycinin, the calculation method of soybean protein in soybean protein beverage was given. [ Result ] The linear detection range of the competitive ELISAs were all 2. 0 to 80 μg/ml （R^2 =0.99）. The extracting solution was 7 mol/L urea with 0.5% DTY. The soybean protein content in soybean protein beverage could be calculated by dividing the total content of glycinin and β-conglycinin by 0.682. The relative standard deviations of the assay were 〈 12%. [ Conclusion] The study can provide reference for protein specificity quantitation of other heat processed food.