pH-Dependent complexation between β-lactoglobulin and lycopene: Multi-spectroscopy, molecular docking and dynamic simulation study

This study aims to investigate the effect of pH levels (pH 7.0 and pH 8.1) on binding ability of beta-lactoglobulin (beta-LG) with lycopene (LYC) and elucidate interaction mechanisms using multi-spectroscopy and molecular docking study. beta-LG at pH 8.1 showed a stronger binding affinity to lycopene than that at pH 7.0 according to binding constant, binding number, energy transfer efficiency, and surface hydrophobicity. Lycopene bound to protein mainly by van der Waals force in the form of static quenching mode and preferred to interact with p-LG at the top of barrel for both pH levels. Molecular dynamic simulation revealed that beta-LG/LYC complex at pH 8.1 was more stable than at pH 7.0. beta-LG/LYC complexes formed at pH 8.1 showed significantly higher ABTS radical scavenging activity than samples at pH 7.0 (p < 0.05). Data obtained may contribute valuable information for preparing a whey protein-based delivery system for lycopene.

Automated summary

The study found that beta-lactoglobulin had a stronger binding affinity to lycopene at pH 8.1, leading to a more stable complex with higher ABTS radical scavenging activity compared to pH 7.0. The data obtained can provide valuable information for developing a whey protein-based delivery system for lycopene.