<i>In Silico</i> and <i>In Vitro</i> Approaches to Predict MepR Efflux Protein Inhibitory Activity of <i>Ocimum sanctum</i> Aqueous Leaf Extract

Background: Ocimum sanctum belonging to Lamiaceae family has been reported to have various medicinal values. Aim: The plant parts especially leaves have various pharmacological activities like antibacterial, antifungal, antioxidant, anti-inflammatory, anti-insecticidal, anti-cancer, anti-metastatic, anti-proliferative, and anti-tumour properties. Methods: Soxhlet extraction method was carried out to extract O. sanctum leaves. Then the extract was studied for its antibacterial activity against Staphylococcus aureus which showed a significant zone of inhibition on growth. Furthermore, through a rigorous literature survey, Oleanolic acid was found to be a predominant compound present in the aqueous leaf extract of O. sanctum. Then, the oleanolic acid was docked against the Multidrug Efflux Pump MepR (PDB ID: 4LLL) of S. aureus, which showed that the binding affinity is strong with a binding energy of -4.7 Kcal/mol. Also, oleanolic acid has passed the drug-likeness by Lipinski’s rule of five and the ADME properties. Results: O. sanctum can be explored more in the future to evaluate its medicinal properties The top compound beta-sesquiphellandrene was docked against the Janus kinase 1 (PDB ID: 4I5C), Janus kinase 2 (PDB ID: 2B7A) which showed that the binding affinity is strong with binding energies -7.3 Kcal/mol and -7.4 Kcal/mol respectively. Also, the lead compound has passed the drug-likeness by Lipinski’s rule of five and the ADME properties. Conclusion: The study shows significant cytotoxic potential in MTT assay with IC50 concentration of the sample nearer to 60 μg/ml. O. sanctum can be explored more in the future to evaluate its medicinal properties. Major Findings: The O. sanctum has significant antibacterial activity against S. aureus and act against the lymphoma cancer cells.