Paradigm of Well-Orchestrated Pharmacokinetic Properties of Curcuminoids Relative to Conventional Drugs for the Inactivation of SARS-CoV-2 Receptors: An In Silico Approach

To cure SARS-CoV-2 infection, the repurposing of conventional antiviral drugs is currently advocated by researchers, though their action is not very effective. The present study, based on in silico methods, was intended to increase the therapeutic potential of conventional drugs: hydroxychloroquine (HCQ), favipiravir (FAV), and remdesivir (REM) by using curcuminoids like curcumin (CUR), bisdemethoxycurcumin (BDMC), and demethoxycurcumin (DMC) as adjunct drugs against SARS-CoV-2 receptor proteins, namely main protease (Mpro) and the S1 receptor-binding domain (RBD). The curcuminoids exhibited similar pharmacokinetic properties to the conventional drugs. The webserver (ANCHOR) predicted greater protein stability for both receptors with a disordered score (<0.5). The molecular docking study showed that the binding energy was highest (−27.47 kcal/mol) for BDMC toward Mpro receptors, while the binding energy of CUR (−20.47 kcal/mol) and DMC (−20.58 kcal/mol) was lower than that of HCQ (−24.58 kcal/mol), FAV (−22.87 kcal/mol), and REM (−23.48 kcal/mol). In the case of S1-RBD, CUR had the highest binding energy (−38.84 kcal/mol) and the lowest was in FAV (−23.77 kcal/mol), whereas HCQ (−35.87 kcal/mol) and REM (−38.44 kcal/mol) had greater binding energy than BDMC (−28.07 kcal/mol) and DMC (−30.29 kcal/mol). Hence, this study envisages that these curcuminoids could be employed in combination therapy with conventional drugs to disrupt the stability of SARS-CoV-2 receptor proteins.