Multi-spectroscopic, thermodynamic and molecular dockimg insights into interaction of bovine serum albumin with calcium lactate

The safety of various food additives such as calcium lactate (CL) has become a challengeable subject in recent years because of their adverse effects on human health and their physiological effects study at the molecular level seems essential. Therefore, in this study, interactions of CL as food preservative with bovine serum albumin (BSA) in aqueous solution were carried out using spectroscopic methods at four different temperatures. The CL quenched the fluorescence of the BSA through both dynamic and static quenching mechanisms. The negative value of enthalpy (Delta H) and the positive value of entropy (Delta S) demonstrated that electrostatic forces played predominant roles in the binding of CL to BSA. Results of UV-VIS spectroscopy studies indicated a ground-state complex formation between BSA and CL. Circular dichroism technique study showed that CL change the secondary structure of BSA through reduction of the alpha-helicity amount. Furthermore, molecular docking experiments indicated that CL could effectively bind into a cavity above Sudlow II (Domain III, subdomain IIIA) with binding energy of - 5.26 kcal/mol.