Jia Yangyang, Yang Ziying, Xu Linshuang, Khalifa Ibrahim, Hu Lanlan, Nie Yuanyang, Li Bo, Liu Benguo, Yang Wei
School of Food Science, Henan Institute of Science and Technology, Xinxiang 453000, China.
Food Technology Department, Faculty of Agriculture, Benha University, Moshtohor, 13736, Egypt.
Food Chem. 2025 Feb 15;465(Pt 2):142047. doi: 10.1016/j.foodchem.2024.142047. Epub 2024 Nov 16.
Three distinct ternary complexes (TC-M1, TC-M2, and TC-M3) based on lactoferrin (LF), (-)-epigallocatechin-3-gallate (EGCG), and α-lactalbumin (ALA) were prepared by varying the assembly sequence and EGCG concentrations (ranging from 0 to 2.0 mM). Structural characterization was performed using various spectroscopic techniques, while the assembly mechanisms were investigated through ITC and molecular docking. These ternary complexes were further evaluated as stabilizers in Pickering emulsions. Nephelometry and DLS analysis showed that TC-M1 exhibited the highest turbidity and largest particle size, followed by TC-M2 and TC-M3. FT-IR and fluorescence spectroscopy revealed strong binding between EGCG and both ALA and LF, enhancing the hydrophilicity and extending structure of proteins. ITC and molecular docking studies indicated spontaneous interactions primarily driven by hydrogen bonding and hydrophobic forces, with LF (Ka1 = 1.9 × 10 M) and ALA (Ka1 = 3.6 × 10 M) binding approximately 3.3 and 2.9 EGCG molecules, respectively. Pickering emulsions formed by these complexes demonstrated superior emulsification properties, with TC-M1 showing the smallest CI (10.09 % ± 0.19 %), particle size (1 to 2 μm), and higher MVI (1.2) and EI (2.5) at 2.0 mM EGCG, outperforming TC-M2 and TC-M3 in stability. Overall, the assembly sequence of LF, ALA, and EGCG, along with EGCG concentration, lays the foundation for designing protein-polyphenol-protein ternary complexes, offering enhanced stability and functionality for diverse EGCG delivery applications.
通过改变组装顺序和表没食子儿茶素-3-没食子酸酯（EGCG）浓度（范围为0至2.0 mM），制备了基于乳铁蛋白（LF）、表没食子儿茶素-3-没食子酸酯（EGCG）和α-乳白蛋白（ALA）的三种不同的三元复合物（TC-M1、TC-M2和TC-M3）。使用各种光谱技术进行结构表征，同时通过等温滴定量热法（ITC）和分子对接研究组装机制。这些三元复合物进一步作为皮克林乳液中的稳定剂进行评估。比浊法和动态光散射（DLS）分析表明，TC-M1表现出最高的浊度和最大的粒径，其次是TC-M2和TC-M3。傅里叶变换红外光谱（FT-IR）和荧光光谱显示EGCG与ALA和LF之间有强烈的结合，增强了蛋白质的亲水性并扩展了其结构。ITC和分子对接研究表明，自发相互作用主要由氢键和疏水作用力驱动，LF（Ka1 = 1.9×10 M）和ALA（Ka1 = 3.6×10 M）分别结合约3.3和2.9个EGCG分子。由这些复合物形成的皮克林乳液表现出优异的乳化性能，在2.0 mM EGCG时，TC-M1的离心稳定性指数（CI）最小（10.09 % ± 0.19 %）、粒径为1至2μm，且具有更高的平均体积直径（MVI，1.2）和乳化指数（EI，2.5），在稳定性方面优于TC-M2和TC-M3。总体而言，LF、ALA和EGCG的组装顺序以及EGCG浓度为设计蛋白质-多酚-蛋白质三元复合物奠定了基础，为多种EGCG递送应用提供了更高的稳定性和功能性。
