Molecular docking of active compounds from traditional medicinal plants as ACE-2 protein (1R4L) inhibitor in searching for COVID-19 drug

Coronavirus disease known as COVID-19 is a global pandemic caused by severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2). SARS-CoV-2 binds to the receptor binding-domain of ACE-2. By blocking it with a specific ligand, we can prevent SARS-CoV-2 binding and therefore prevent its cellular entry and injury. The number of COVID-19 cases is still increasing and yet only 2.5% of Indonesians are fully vaccinated. Moreover, up to now, a specific cure for COVID-19 has not been found yet. However, many traditional medicinal plants have the potency of becoming COVID-19 drugs. Therefore, this study aimed to examine various active compounds derivate from the traditional medicinal plant as an inhibitor of SARS-CoV-2 receptor in human cell termed as ACE2. The activity and drug-likeness of the active compounds were predicted and molecular docking were conducted to identify the interactions between ligands and ACE-2. Toxicity assay was also identified to predict the toxicity class, lethal dose, and organ toxicity. This study showed that indirubin has lower binding energy as compared to the sulabiroins A and MLN-4760 as comparative control and potent inhibitor control, respectively. Indirubin shared similar interaction with amino acid residue to ACE-2 as compared to control. Based on the research result, it was suggested that Indirubin could be developed as a promising compound for COVID-19 antiviral drugs. KEYWORDS: ACE-2 inhibitor, Antiviral drug, Coronavirus, Indirubin, Sulabiroins A