Discovery of Potential Inhibitors of the Receptor-binding Domain (RBD) of Pandemic Disease-causing SARS-CoV-2 Spike Glycoprotein from Triphala Through Molecular Docking

Abstract

Background: COVID-19 (SARS-CoV-2 infection) has affected almost every region of the world. Presently, there is no defined line of treatment available for it. Triphala is already proven to have a safe biological window, which is well known for its antioxidant and immunomodulatory properties. Objective: The present work has been carried out to study Triphala's effectiveness in the treatment of COVID-19. Methods: The Receptor-binding domain (RBD) of SARS-CoV-2 Spike Glycoprotein is responsible for the invasion into the host cell, which leads to further infection. The molecular docking (MD) was performed to explore the binding affinities (kcal/mol) of Triphala's chemical constituents and compared them with the existing drugs under investigation for the treatment of COVID-19 epidemiology. Results: Chebulinic acid binding affinity -8.5 kcal/mol with the formation of 10 hydrogen bonds. Almost all the major chemical constituents have formed two or more hydrogen bonds with RBD of SARS-CoV-2 Spike Glycoprotein. Conclusion: The present study showed that Triphala might perform vital roles in the treatment of COVID-19 and expand its usefulness to physicians to treat this illness. There is a need to complete the in-vitro, in-vivo biological testing of Triphala on SARS-CoV-2 disease to create more quality data. The binding mode of Chebulinic acid in the allosteric cavity allows a better understanding of RBD of SARS-CoV-2 Spike Glycoprotein target and provides insight for the design of new inhibitors. Triphala is already proven to have a safe biological window, which indicates that we can skip the pre-clinical trials. Apart from this, Triphala is well known for its antioxidant properties, which ultimately improve the immunity of the COVID-19 patient.