Research Article
Xiangrong Li*, Zhenhua Yang, K
Abstract
In this study, the interactions between procyanidin B3 and papain/bromelain were investigated by fluorescence spectroscopy. The results show that the quenching mechanisms are all static quenching at lower concentrations of procyanidin B3, but at higher concentrations of procyanidin B3, maybe predominantly by static-dynamic combined quenching mechanism. The interactions for procyanidin B3 to papain is an enthalpy process and the main intermolecular interactions are van der Waals and hydrogen bond interactions. The binding of procyanidin B3 and bromelain is synergistically driven by enthalpy and entropy, electrostatic and hydrophobic interactions play major roles in the reaction. The binding affinity of procyanidin B3-papain complex is stronger than procyanidin B3-bromelain complex. Synchronous fluorescence spectroscopy shows the interaction between procyanidin B3 and papain/bromelain decreases the hydrophobicity of the microenvironment of tryptophan and tyrosine residues. The study provides an accurate and full basic data for clarifying the binding mechanism of procyanidin B3 with papain/bromelain and is helpful for understanding procyanidin B3’s rational use in the food industry as dietary supplements.