大豆7S球蛋白热力学特性、溶解性和溶液性质与表面疏水性相关性研究

Relevance between thermodynamic characteristics,solubility,solution properties and surface hydrophobicity of soybean β-conglycinin(7S)

以6个具有代表性的大豆品种制备的7S球蛋白为实验对象,采用ANS荧光探针法测定表面疏水性,采用差示扫描量热法分析热力学特性,采用体积排阻-凝胶色谱法分析溶液的相对分子质量及其分布,采用Zeta Plus电位及激光粒度分析仪分析流体动力学粒径及其分布并测定ξ-电位,研究大豆7S球蛋白热力学特性、溶解性和溶液性质与表面疏水性的关系。结果表明:大豆7S球蛋白的表面疏水性与变性温度、变性焓、ξ-电位绝对值均呈显著负相关;大豆7S球蛋白的溶解性与表面疏水性呈极显著负相关;大豆7S球蛋白溶液可溶性聚集物的平均相对分子质量、平均粒径与表面疏水性呈显著正相关。

β- Conglycinin （7S） was prepared with soybean from six representative regions. Surface hydrophobicity of 7S was determined by ANS fluorescent probe method. Thermodynamic characteristics was analyzed by differential scanning calorimetry. Relative molecular weight distribution was determined by size exclusion gel chromatography. Hydrodynamic particle size distribution and ξ - potential were determined by Zeta Plus potential and laser particle size analyzer. The relationships between thermody- namic characteristics, solubility, solution properties and surface hydrophobicity of soybean 7S were stud- ied. The results showed that there were significantly negative correlations between surface hydrophobicity of 7S and thermal denaturation temperature, denaturation enthalpy, and ξ- potential. There was extremely and significantly negative correlation between surface hydrophobicity and solubility of 7S. There was significantly positive correlation between surface hydrophobicity of 7S and average relative molecular weight and average particle size of soluble aggregates in 7S solution.