In-Silico Study on the Interaction of Saffron Ligands and Beta-Lactoglobulin by Molecular Dynamics and Molecular Docking Approach

Safranal, crocetin, and dimethylcrocetin are secondary metabolites found in saffron and have a wide range of biological activities. An investigation of their interaction with a transport protein, such as β-lactoglobulin (β-lg), at the atomic level could be a valuable factor in controlling their transport to biological sites. The interaction of these ligands and β-lg as a transport protein was investigated using molecular docking and molecular dynamics (MD) simulation methods. The molecular docking results showed that safranal and crocetin bind on the surface of β-lg. However, dimethylcrocetin binds in the internal cavity of β-lg. The β-lg affinity for binding saffron ligands decreases in the following order: crocetin > dimethylcrocetin > safranal. The analysis of MD simulation trajectories showed that the β-lg and β-lg–ligand complexes became stable at approximately 3000 ps and that there was little conformational change in the β-lg–safranal and β-lg–dimethylcrocetin complexes over a 10-ns timescale. In addition, the profiles of atomic fluctuations showed the rigidity of the ligand binding site during the simulation time.