在这项研究中,通过检查高压处理(HPP)和热处理对pH值为6.0、7.4和8.0时α-乳白蛋白(α-La)和天花3-葡糖苷(P3G)之间的结合行为和相互作用的影响,进行了比较评估。圆二色光谱的方法,荧光猝灭,动态光散射,和分子模拟用于表征加工诱导的蛋白质结构变化的影响,大小分布,结合位点构象,以及它们之间的结合特性的残余电荷。结果表明,在pH7.4/8.0和60/80°C下,热处理显着增加了络合物的淬火常数,以及在pH8.0/80°C下蛋白质的可接近部分。HPP和热处理均增加了无规卷曲含量,对α-La的α-螺旋和β-折叠含量的影响有限,并导致复合物的聚集程度不同。分子动力学模拟和对接分析表明,在不同的加工条件下,复合物的结合位点没有变化,但是溶剂可及表面积在不同条件下有所不同。
In this study, high pressure processing (HPP) and thermal treatment were comparatively evaluated by examining their impacts on the binding behavior and interaction between α-lactalbumin (α-La) and pelargonium-3-glucoside (P3G) under pH values of 6.0, 7.4, and 8.0. The methods of circular dichroism spectroscopy, fluorescence quenching, dynamic light scattering, and molecular simulation were used to characterize the effects of processing-induced changes in protein structure, size distribution, binding site conformation, and residue charges on their binding characteristics between them. The results indicated that the thermal treatments significantly increased the quenching constants of the complex at pH 7.4/8.0 and 60/80 °C, as well as the accessible fraction of protein at pH 8.0/80 °C. Both HPP and thermal treatments increased the random coil content and showed limited effects on the α-helix and β-sheet contents of α-La and caused the aggregation of the complex to varying degrees. Molecular dynamic simulation and docking analyses revealed that the binding site of the complex did not change under different processing conditions, but the solvent-accessible surface area varied under different conditions.