In Silico Screening of Breadfruit (Artocarpus altilis) Prenylated Flavonoids Identify Potential SARS-CoV Inhibitors

Coronavirus Disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is a global health threat. Traditional herbals and dietary plants with medicinal values have a long antiviral history and, thus, are extensively studied in COVID-19 therapeutics development. Breadfruit (Artocarpus altilis) is a food crop with rich nutrient composition. This study screened selected breadfruit prenylated flavonoids for their potential inhibitory activities against the SARS-CoV family receptors using molecular docking and molecular dynamics (MD) simulation. The A. altilis prenylated flavonoids were selected as target ligands (artocarpin, artoindonesianin V, artonin M, cudraflavone A and cycloartobiloxanthone) and molecular targets from the SARS-CoV family were designated as receptors. Molecular docking was applied with the Lamarckian Genetic algorithm to measure the receptor-ligand orientation using AutoDock Vina software. The structural interactions of the receptor-ligand complexes were visualised using the Biovia Discovery Studio 4.5. Under all possible receptor-ligand combinations, the complexes’ minimum binding affinities (MBA) ranged from -5.5 to -9.1 kcal/mol and held by hydrophobic interactions, hydrogen bonds and electrostatic attractions. Receptor-ligand complexes with the least MBA (<-6.0 kcal/mol) along with strong structural interactions were validated by MD simulation using the GROMACS software. The 5RE4-artocarpin and 5RE4-artoindonesianin V showed the highest hydrophobic interactions at MBA=-6.6 kcal/mol and -6.4 kcal/mol, respectively. The trajectory analysis of 5RE4-artocarpin and 5RE4-artoindonesianin V complexes was fairly stable throughout a 50 ns MD simulation run. The findings conclude that artocarpin and artoindonesianin V are good potential SARS-CoV family receptor inhibitors.