米渣蛋白中谷蛋白与亚油酸的相互作用机制

利用荧光猝灭光谱、8-苯胺基-1-奈磺酸(1-anilinonaphthalene-8-sulfonic acid,ANS)结合荧光光谱、紫外-可见吸收光谱及圆二色光谱法研究了谷蛋白(rice glutelin,RG)与亚油酸复合体系的结构变化、荧光特性、结合机制及热力学特性。荧光猝灭实验结果表明:亚油酸可使谷蛋白发生荧光猝灭,猝灭机制为静态猝灭,且亚油酸与谷蛋白之间主要相互作用为疏水性相互作用。ANS结合荧光光谱、紫外-可见吸收光谱及圆二色光谱法实验数据表明:亚油酸的加入会使谷蛋白的二级结构及三级结构发生变化,α-螺旋结构含量明显增加,蛋白质稳定性增强。两者相互作用的研究可为实际生产高纯度蛋白质及新型蛋白产品提供理论依据。

Interaction Mechanism of Gluten and Linoleic Acid in Rice Dreg Protein

Structural changes, fluorescence characteristics, binding mechanism and thermodynamic features of gluten and linoleic acid composite system in rice dreg protein were studied using fluorescence quenching spectroscopy, 1-anilinonaphthalene-8-sulfonic acid (ANS) fluorescence spectroscopy, ultraviolet-visible (UV-Vis) absorption spectroscopy and circular dichroism (CD) spectroscopy. The fluorescence spectral results showed that the endogenous fluorescence of gluten was significantly quenched by linoleic acid and the mechanism of fluorescence quenching was static quenching. The major driving force was hydrophobic interactions. Meanwhile, the ANS fluorescence, UV-Vis absorption and CD spectral data showed that the secondary and tertiary structure of gluten were changed by the addition of linoleic acid. A significant increase in α-helix structure content was observed and protein stability was enhanced. This study will provide a theoretical basis for the production of high-purity protein and innovative protein product systems.