Study of the Interaction Between Some Flavonoids of Plant Origin with COVID-19 Main Protease by Molecular Docking Method

The spread of coronavirus disease 2019 (COVID-19) pandemic in all countries causing a global effort to discovered rugs or vaccines. The potential of 70 plant origin-flavonoids for inhibition of the main protease of COVID-19 was investigated the molecular docking approach. COVID-19 Docking Server was applied to check the inhibitor activity of the flavonoids in comparison to the native protease inhibitor of the main protease. Results suggest five compounds namely rutin, neohesperidin, poncirin, naringin, and theaflavin. For these compounds, the predicted binding energy was respectively -9.5, -9.2, -8.9, -8.8, and -8.8 kcal/mol in comparison to the -8.5 kcal/mol value for the native inhibitor. The hydrogen bond with residues Ser46, Gly143, His163 and hydrophobic interaction with residues Asn142, Gly143, Cys145, and Met165 are the major interaction between selected flavonoids with the main protease. Anti-GRP78 flavonoids naringin and poncirin are repurposing flavonoids for inhibition of Mpro of COVID-19 that previously their inhibitory effects were appeared by our using invitro analysis for GRP78. Also, rutin was proposed based on the consensus decision-making along with other studies for the inhibitory effect of flavonoids against the main protease of COVID-19.