GC-MS, LC-MS/MS, Docking and Molecular Dynamics Approaches to Identify Potential SARS-CoV-2 3-Chymotrypsin-Like Protease Inhibitors from Roscoe.

This study aims to identify and isolate the secondary metabolites of using GC-MS, preparative TLC, and LC-MS/MS methods, to evaluate the inhibitory potency on SARS-CoV-2 3 chymotrypsin-like protease enzyme, as well as to study the molecular interaction and stability by using docking and molecular dynamics simulations. GC-MS analysis suggested for the isolation of terpenoids compounds as major compounds on methanol extract of pseudostems and rhizomes. Isolation and LC-MS/MS analysis identified 5-hydro-7, 8, 2'-trimethoxyflavanone (), ()-hexadecyl-ferulate (), isocyperol (), isobutyl-(2,4)-octadecadienamide (), and nootkatone () from the rhizome extract, as well as from the leaves extract with the absence of . Three known steroid compounds, i.e., spinasterone (), spinasterol (), and 24-methylcholesta-7-en-3-on (), were further identified from the pseudostem extract. Molecular docking showed that steroids compounds , , and have lower predictive binding energies (MMGBSA) than other metabolites with binding energy of -87.91, -78.11, and -68.80 kcal/mole, respectively. Further characterization on the single isolated compound by NMR showed that was identified and possessed 75% inhibitory activity on SARS-CoV-2 3CL protease enzyme that was slightly different with the positive control GC376 (77%). MD simulations showed the complex stability with compound during 100 ns simulation time.