Relationship Between Surface Hydrophobicity and Structure of Soy Protein Isolate Subjected to Different Ionic Strength
Relationship Between Surface Hydrophobicity and Structure of Soy Protein Isolate Subjected to Different Ionic Strength
复制标题
不同离子强度下大豆分离蛋白表面疏水性与结构的关系
DOI：
10.1080/10942912.2013.865057
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发表时间：
2015-05-04
影响因子：
2.9
通讯作者：
Zhou, Linyi
中科院分区：
文献类型：
--
作者：
Jiang, Lianzhou;Wang, Zhongjiang;Zhou, Linyi
研究了离子强度对大豆分离蛋白表面疏水性、溶解性和空间结构的影响。随着离子强度的增加，表面疏水性与其溶解度呈负相关。大豆分离蛋白的空间结构的变化解释了离子强度引起的表面疏水性增加。离子强度增加对蛋白质二级结构的影响主要表现在无规卷曲增加和α-螺旋含量减少，表明离子效应可能使蛋白质结构松散，改变表面氨基酸分布。色氨酸的荧光光谱λ max发生了位移，而拉曼光谱I-850/I-830值相对较高，表明酪氨酸残基在蛋白质表面的暴露程度。此外，拉曼光谱所反映的二硫键振动模式的变化也支持了盐水对大豆分离蛋白表面疏水性和结构的影响。这些结果有助于了解盐度对大豆分离蛋白表面疏水性的影响，并有助于预测大豆分离蛋白在体系中的其他功能特性。
The impact of ionic strength on surface hydrophobicity, solubility, and spatial structure of soy protein isolate were investigated in this article. Surface hydrophobicity was found to be negatively correlated with its solubility as ionic strength increased. The changes in spatial structure of soy protein isolate accounted for the increased surface hydrophobicity caused by ionic strength. Specifically, changes in secondary structures by increased ionic strength were mainly reflected in the increased random coil and decreased alpha-helices content, which suggested that ionic effects may loosen the protein structures and result in the modification of surface amino acid distribution. This is further verified by the shifted lambda(max) in fluorescence spectra of tryptophan and relative high I-850/I-830 value in Raman spectra, which was an indicator of the exposure degree of tyrosine residues on the surface of the protein. In addition, the changes in vibration modes of disulfide bonds reflected by Raman spectra also support the impact of saline on the surface hydrophobicity and structure of soy protein isolate. It is believed that these findings could be helpful to understand the impact of salinity on the surface hydrophobicity of soy protein isolate as well as to predict the other functional characteristics of soy protein isolate in system.