亚油酸氢过氧化物氧化修饰对大豆蛋白热变性和聚集的影响

摘要

以亚油酸氢过氧化物代表脂质氢过氧化物氧化修饰大豆分离蛋白,采用圆二色光谱、内源荧光光谱、粒径分析以及相对分子质量分布研究氢过氧化物氧化修饰对大豆蛋白热变性和聚集的影响.结果发现亚油酸氢过氧化物氧化修饰使得大豆蛋白热稳定性下降,热变性过程中形成聚集体粒径随着蛋白质氧化程度的升高呈现先增加后减小的趋势,热变性大豆蛋白冷却后的粒径和聚集体含量则随着蛋白质氧化程度的增加而下降.%Linoleic acid hydroperoxide was selected as a representative of lipid hydroperoxide to investigate the effects of oxidative modification by lipid hydroperoxide on the thermal denaturation and aggregation of soy protein by circular dichroism, intrinsic fluorescence, particle size analysis and relative molecular weight distribution. The results revealed that oxidative modification by linoleic acid hydroperoxide resulted in a decrease of thermal stability of soy protein. As the extent of soy protein oxidation increased,the particle size of aggregation increased first, and then decreased during the thermal denaturation course. The particle size and aggregation content of cooled thermal - induced denaturated soy protein decreased as the extent of protein oxidation increased.