Experimental and computational investigation on the molecular interactions of safranal with bovine serum albumin: Binding and anti-amyloidogenic efficacy of ligand

Molecular interaction between BSA and safranal was seen in the present study using experimental and molecular docking methods, in addition, inhibitory effect of safranal towards BSA amyloid formation was also seen. UV-visible and fluorescence studies suggested the formation of 1:1 complex between BSA and safranal via static quenching mechanism. The corrected fluorescence spectra showed a blue shift in the emission maximum on the successive addition of safranal which revealed the involvement of hydrophobic forces in the interaction. Far-UV CD measurements suggested the stabilization of secondary structure of BSA by increasing its alpha-helical contents, i.e compaction of protein and that was further supported by RLS and DLS methods. Analysis of thermodynamic parameters presented that hydrophobic forces as well as hydrogen bonding were involved in the binding. From the competitive assay and molecular docking simulations it was found that safranal binds near the Sudlow's site 1 in the subdomain IIA and most of the amino acids residues bound with hydrophobic forces and a few with hydrogen bonding. Safranal was found to inhibit the BSA amyloid formation and the inhibition was concentration dependent. Exposed surface hydrophobicity of BSA amyloid fibrils was decreased considerably in presence of safranal. (C) 2019 Elsevier B.V. All rights reserved.