Abstract
Human coronavirus infections, particularly those caused by SARS-CoV-2, remain a significant public health concern. Researchers are actively exploring new antiviral compounds, including those derived from marine natural products. This study investigates fucoxanthin (FX) and its metabolites, fucoxanthinol (FXOH) and amarouciaxanthin A (AXA), as potential inhibitors of the SARS-CoV-2 nucleocapsid phosphoprotein (NP) using molecular docking. Molecular dynamics simulations were performed for 100 ns, along with the reference drug, ribavirin, for comparative purposes. Compared to ribavirin (- 5.870 kcal/mol), FXOH (- 5.662 kcal/mol), AXA (- 5.189 kcal/mol), and FX (- 4.594 kcal/mol), the binding energies were low. RMSD analysis revealed that the NP-ribavirin (1.4-3.8 Å) exhibit a more rigid protein confirmation. In constant, the NP-FX (2.4-4.8 Å), and NP-FXOH (2.5-4.5 Å) showed moderate fluctuations, reflecting the inherent flexibility of the protein. cDFT analysis (HOMO &LUMO) revealed that FX had higher electronic reactivity and charge-transfer capability, whereas FXOH showed greater electronic stability. From these observations, the FX and FXOH remained in the binding site during the MD simulation, and they can be used as an antiviral drug formulation. However, this study is limited to computational prediction, and further in vitro and in vivo investigations are needed to validate the efficacy, safety, and pharmacokinetic properties of ligands.