@article{ZHAI2024, 
author = {Xiaoyu ZHAI and Wenjiang DONG and Xinxin YU and Rongsuo HU},
title = {Interactions between β-Lactoglobulin and Three Major Polyphenols in Coffee under Different pH Environments},
year = {2024},
journal = {Food Science},
volume = {45},
number = {19},
pages = {26-40},
keywords = {polyphenol, β-lactoglobulin, non-covalent interaction, multispectroscopic techniques, molecular docking},
url = {https://www.sciopen.com/article/10.7506/spkx1002-6630-20231104-027},
doi = {10.7506/spkx1002-6630-20231104-027},
abstract = {The purpose of this study was to explore the non-covalent interactions between three major polyphenols (chlorogenic acid, caffeic acid and ferulic acid) in coffee and β-lactoglobulin (β-LG) at different pH values and their effects on protein structure by multispectroscopic techniques and molecular docking. The results showed that all three coffee polyphenols statically quenched the fluorescence of β-lactoglobulin under two pH conditions. At pH 7.4 and 298 K, the quenching constants (Ksv) of chlorogenic acid, caffeic acid and ferulic acid for β-lactoglobulin were 6.53 × 104, 3.16 × 104 and 3.09 × 104 L/mol with 1.20, 1.02 and 1.14 binding sites and energy transfer efficiency of 34.55%, 24.56% and 21.35%, respectively. At pH 3.0 and 298 K, the Ksv were 7.18 × 104, 5.24 × 104 and 7.12 × 104 L/mol with 1.28, 1.18 and 1.25 binding sites and energy transfer efficiency of 34.70%, 30.42% and 29.65%, respectively. The results of circular dichroism showed that the α-helix content of β-LG decreased and the β-sheet content increased at pH 7.4, and the β-sheet content increased and the random coil content decreased at pH 3.0. The results of molecular docking showed that the three polyphenols could bind to the hydrophobic pocket of β-lactoglobulin mainly through hydrogen bonds, van der Waals force and hydrophobic interaction. This study preliminarily revealed the interaction mechanism between β-lactoglobulin and chlorogenic acid, caffeic acid and ferulic acid in coffee milk beverage under different pH conditions.}
}