Molecular docking and simulation studies to prove the antimicrobial property of cowpea extract

Abstract

This study is undertaken to prove the antimicrobial potential of the methanolic extracts of the seeds of cowpea (Vigna unguiculata) for the antimicrobial assay and biochemical characterization. The knowledge about the type of compound and its nature were obtained using characterizations including UV-Visible analysis and GC-MS. The extracts of cowpea displayed a zone of inhibition which is 13-17 mm, against Staphylococcus aureus being the most sensitive. Thin-layer chromatography, GC-MS and UV-Vis results showed the presence of methyl esters in higher amounts in the extracts with small amounts of sterols, suggesting that methyl esters can be the cause of the biological activity seen in the present work. SwissADME tool helped in screening the absorption, distribution, metabolism and excretion parameters of the identified phytoligands. Molecular docking results were following the in vitro studies performed. Protein-ligand docking using AutoDock 4.0 software was used for the validation of the wet-lab results. Binding energies were calculated for each ligand and its interaction with amino acids in the active site of the target protein. Among all the ligands tested 9-Octadecenoic Acid has emerged most promising against DNA topoisomerase of Staphylococcus aureus. The molecular dynamic simulation was also done to access the stability of the docked complex concerning temperature, hydrogen bonds, and hydrophobic interactions. Cowpea could be used as an effective antimicrobial agent in human welfare.