Spectroscopic, molecular docking and molecular dynamic simulation studies on the complexes of β-lactoglobulin, safranal and oleuropein

Herbal bioactive compounds have captured pronounced attention considering their health-promoting effects as well as their functional properties. In this study, the binding mechanism between milk protein bovine beta-lactoglobulin (beta-LG), oleuropein (OLE) and safranal (SAF) found in olive leaf extract and saffron, respectively via spectroscopic and in silico studies. Fluorescence quenching information exhibited that interactions with both ligands were spontaneous and hydrophobic interactions were dominant. Also, the CD spectroscopy results demonstrated the increase in beta-sheet structure and decrease in thea-helix content for both ligands. Size of beta-LGOLE complex was higher than beta-LG-SAF due to the conformation and larger molecular size. Molecular docking and simulation studies revealed that SAF and OLE bind in the central calyx of beta-LG and the surface of beta-LG next to hydrophobic residues. Lastly, OLE formed a more stabilized complex compared to SAF based on the molecular dynamic simulation results. (C) 2020 Elsevier B.V. All rights reserved.