【摘要】 为探究超声辅助pH值偏移对大豆亲脂蛋白（soybean lipophilic proteins,SLP）结构和功能性的影响，将分离提取的SLP在超声（240 W、20 min）及极端pH值（pH 1或12）条件下进行改性。采用十二烷基硫酸钠-聚丙烯酰胺凝胶电泳、游离巯基含量、傅里叶变换红外光谱、荧光光谱等对不同处理的SLP一级、二级、三级结构进行表征，并对SLP功能性质进行分析。结果表明：超声辅助pH 12偏移处理下SLP结构-功能性改变最大，平均粒径由5 245.33 nm降低至447.13 nm,ζ-电位值由-5.95 mV下降至-18.53 mV，游离巯基含量下降，α-螺旋相对含量增加，荧光光谱发生蓝移，荧光强度降低；同时溶解度由9.84%上升至92.04%，乳化性、起泡性提高。因此超声和pH值偏移处理对SLP结构性质和功能性质具有协同作用，且结构和功能性质相关性较密切。更多还原

【Abstract】 This study aimed to explore the effect of ultrasound-assisted pH shift on the structural and functional properties of soybean lipophilic proteins(SLP). SLP were modified under ultrasound(240 W, 20 min) and extreme pH(pH 1 or 12)conditions. The primary, secondary and tertiary structures of native and modified SLP were characterized by sodium dodecyl sulfate polyacrylamide gel electrophoresis(SDS-PAGE), free sulfhydryl content, Fourier transform infrared(FTIR) spectroscopy, and fluorescence spectroscopy, and their functional properties were analyzed. The results showed that ultrasound-assisted alkaline pH shift resulted in the greatest changes in the structural and functional properties of SLP. The average particle size of SLP decreased from 5 245.33 to 447.13 nm, the ζ-potential value decreased from-5.95 to-18.53 mV,the free sulfhydryl content decreased, the α-helix content increased, and the fluorescence spectrum exhibited a blue shift and a decrease in fluorescence intensity. In addition, the solubility increased from 9.84% to 92.04%, and the emulsifying and foaming properties increased. Therefore, ultrasound and pH shift treatments have a synergistic effect on the structural and functional properties of SLP, and they are closely correlated with each other.更多还原