pH值对大豆分离蛋白构象及表面疏水性的影响  

Effect of pH on Conformation and Surface Hydrophobicity of Soybean Protein Isolate

作　　者：王中江[1] 江连洲[1,2] 魏冬旭[1,3] 李杨[1] 王辰[1] 李丹[1,4] 

机构地区：[1]东北农业大学食品学院,黑龙江哈尔滨150030 [2]国家大豆工程技术研究中心,黑龙江哈尔滨150030 [3]黑龙江出入境检验检疫局,黑龙江哈尔滨150001 [4]宁德师范学院,福建宁德352100

出　　处：《食品科学》2012年第11期47-51,共5页Food Science

基　　金：国家自然科学基金项目(C200101)

摘　　要：采用Lowery法、ANS荧光探针法、圆二色光谱、荧光光谱方法分别对不同pH值大豆分离蛋白溶解度、表面疏水性、蛋白质二级、三级结构进行分析。结果表明:随着pH值的升高,大豆分离蛋白的二级结构发生由β-折叠结构向α-螺旋结构的转变,其Trp残基所处微环境极性增强。大豆分离蛋白表面疏水性与溶解度呈负相关关系,同时大豆分离蛋白表面疏水性也与α-螺旋结构含量呈负相关关系。Lowry method, ANS fluorescence probe, circular dichroism and fluorescent spectroscopy were applied to explore the solubility, surface hydrophobicity, secondary structure and tertiary structure of soybean protein isolate at different pH conditions. The results showed that the transformation from β-sheet structure to α-helix structure, and the rnicroenvironment polarity of Trp residues revealed an obvious increase with increasing pH. A negatively linear correlation between the surface hydrophobicity and solubility of soybean protein isolate was observed. Meanwhile, the surface hydrophobicity of soybean protein isolate was negatively correlated with the amount of α-helix structure.

关 键 词：大豆分离蛋白 PH值 表面疏水性 构象 

分 类 号：TS201.2[轻工技术与工程—食品科学]