Exploring thermodynamic parameters and the binding energetic of berberine chloride to bovine serum albumin (BSA): Spectroscopy, isothermal titration calorimetry and molecular docking techniques

The present study reveals a mechanistic approach of binding mode of berberine chloride with bovine serum albumin (BSA) using isothermal titration calorimetry (ITC), fluorescence quenching, circular dichorism (CD), UV-vis absorption spectroscopy and molecular docking techniqes. Thermodynamic profile clearly demonstrated that the binding was endothermic and spontaneous process. The major binding force involved in complexation of berberine chloride to BSA was hydrophobic interactions. Static quenching is the foremost fluorescence quenching mechanism between BSA and berberine chloride and there is one binding site in BSA for berberine chloride. Molecular docking and competitive binding probes denoted that the binding of berberine chloride to BSA primarily took place in site I i.e. sub-domain IIA. Additionally, the alteration of the BSA secondary structure in the presence of berberine chloride were confirmed by UV-vis, circular dichroism spectral analysis. All these results demonstrated that berberine chloride can bind to BSA.