Investigation on the interaction behavior between safranal and pepsin by spectral and MD simulation studies

Abstract

The ability of therapeutic molecules to bind to enzymes is critical for determining their therapeutic effects. We've chosen safranal, a monoterpene aldehyde found in saffron petals among therapeutic molecules that are known to have antioxidant, anti-inflammatory, tumor-killing, anti-genotoxic, and anti-aging effects. The purpose of this study was to see how safranal interacts with pepsin in an aqueous solution under physiological circumstances. UV–Visible spectroscopy, fluorescence spectra, circular dichroism (CD) analysis, and kinetic approaches, as well as molecular simulation and docking, were used to investigate the effects of safranal on the structure, kinetics, and dynamics of pepsin. Stern-Volmer (Ksv) constants were calculated for the pepsin-safranal complex at different temperatures, indicating that safranal decrease enzyme emission using a static method. With safranal binding, the Vmax and the kcat/Km values increased. UV–Visible and fluorescence spectroscopy and CD findings indicated that safranal binding to pepsin causes micro-environmental alterations around pepsin, which can modify the enzyme's secondary structure. Therefore, safranal causes changes in the structure and function of pepsin. Analysis of MD bonding, simulation methods, and thermodynamic parameters showed that non-covalent reactions, including van der Waals forces, and hydrogen bonds play a critical role in the interaction of safranal with pepsin. The results conclude of CD, and spectroscopic experiments were further supported by molecular dynamics simulations and molecular docking data.