小米蛋白提取、测定以及SDS-PAGE电泳

Extraction, assay and SDS-PAGE electrophoresis of millet protein

依照Osborne法对小米清蛋白、球蛋白、醇溶蛋白和谷蛋白进行分离提取,通过单因素试验确定小米蛋白提取时的最佳条件,并通过SDS-PAGE对小米蛋白组分进行了亚基分析。结果表明,小米清蛋白提取的最佳温度为40℃,球蛋白提取的最佳氯化钠质量分数为2%,醇溶蛋白提取的最佳醇体积分数为80%,谷蛋白提取的最佳氢氧化钠浓度为0.05 mol/L。小米蛋白各组分SDS-PAGE凝胶电泳图谱显示,小米清蛋白的亚基主要分布在(97.4~22)ku范围内且含有二硫键;小米球蛋白的亚基主要分布在(66.2~10)ku范围内;小米醇溶蛋白的亚基条带分布广泛且含有二硫键;小米谷蛋白的亚基条带分布在(66.2~10)ku范围内。不同提取条件不仅会影响提取率,同时也会影响蛋白组分的亚基组成。

In this paper, the separation and extraction of albumin, globulin, prolamin and glutenin were performed according to the Osborne method. The optimum conditions for the extraction of millet protein were determined by single-factor experiments, and the subunits of the millet protein fractions were analyzed by SDS-PAGE. The results showed that the optimum temperature for the extraction of millet albumin was 40 ℃, the optimum concentration of Na Cl for the extraction of millet globulin was 2%, the optimum concentration of alcohol for the extraction of millet prolamin was 80%, and the optimum concentration of Na OH for the extraction of millet glutelin was 0.05 mol/L. The SDS-PAGE map of millet protein fractions showed that the subunits of millet albumin were mainly distributed in the range of（97.4-22）ku and contained disulfide bond. The subunits of millet globulin were mainly distributed in the range of（66.2-10）ku. The subunits of the millet prolamin were widely distributed and contained disulfide bond. The subunits of millet glutelin were distributed in the range of（66.2-10）ku. Different extraction conditions could affect the extraction rate and the subunit composition of the protein component.