Protein-ligand Interaction Modeling between Bovine Serum Albumin (BSA) with M3A and M3GA using Molecular Docking Simulations

Abstract

Introduction: Anthocyanins are natural pigments with potential applications as food colorants; however, their instability under environmental conditions limits their utilization. Protein–anthocyanin interactions, particularly with Bovine Serum Albumin (BSA), may improve anthocyanin stability through non-covalent complex formation. This study aimed to investigate the interaction between BSA and two anthocyanin derivatives, namely Malvidin-3-O-arabinoside (M3A) and Malvidin-3-O-galactoside (M3GA), using molecular docking simulations.

Materials and Methods: Molecular docking simulations were performed using the crystal structure of BSA (PDB ID: 4F5S). Ligand structures of M3A and M3GA were obtained from the PubChem database and optimized using the MMFF94 force field. Protein preparation and visualization analyses were conducted using BIOVIA Discovery Studio Visualizer and ChimeraX, while docking simulations were carried out using the CB-Dock2 platform. Binding affinity and ligand–receptor interaction profiles were analyzed based on binding free energy (ΔG) values and amino acid interactions.

Results: Both M3A and M3GA exhibited favorable binding affinity toward BSA with identical binding free energy values of −8.2 kcal/mol, indicating spontaneous and thermodynamically stable interactions. Interaction analysis revealed that the complexes were stabilized through hydrogen bonds, hydrophobic interactions, electrostatic interactions, Pi–Pi stacked interactions, and van der Waals forces. M3GA formed more hydrogen bond interactions, whereas M3A showed dominant hydrophobic and electrostatic interactions.

Conclusion: The results suggest that both anthocyanin derivatives can form stable complexes with BSA, indicating the potential role of BSA as a stabilizing carrier protein for anthocyanins in food and pharmaceutical applications. Further experimental studies are needed to validate the stability of these complexes under physiological and processing conditions.