Computational screening of phytocompounds from C. amboinicus identifies potential inhibitors of influenza A (H3N2) virus by targeting hemagglutinin

The H3N2 subtype of the influenza A virus continues to be a notable public health issue due to its association with seasonal epidemics and severe human morbidity. The constrained effectiveness of current antiviral medications, combined with the inevitable emergence of drug-resistant variants, mandates the exploration of innovative therapeutic approaches. This study focuses on the identification of phytocompounds from Coleus amboinicus with the potential to target hemagglutinin, viral protein involved in viral entry by binding to sialyl glycoconjugates receptors on the surface of host cells. Molecular docking studies were carried out to assess the efficacy of C. amboinicus phytocompounds with hemagglutinin receptor-binding site. The study revealed that among the 84 signature phytocompounds, isosalvianolic acid and salvianolic acid C showed the highest docking scores and favourable intermolecular interactions. Pharmacokinetic analysis and Pan-assay interference compounds (PAINS) filtering confirmed that isosalvianolic acid meets the criteria outlined in Lipinski's rule of five, exhibits favourable ADMET profiles and passes PAINS filters. Furthermore, the molecular dynamics simulations followed by radius of gyration (Rg), solvent accessible surface area (SASA), and MM-PBSA calculations for binding free energy, verified the stability of the docked complexes. Together, the study identifies isosalvianolic acid as a promising inhibitor of the H3N2 virus by binding to hemagglutinin, indicating its potential as a strategy for therapeutic intervention.