4.  Conclusion
This study used molecular docking and MD simulation as potential tools to monitor the inhibitory efficiency of natural spice molecules against SARS-CoV-2, which emerged as a global threat to millions of people across the globe. It is observed that all the proposed spice molecules qualified the ADME test with their suitable pharmacokinetic properties to be useful as a drug candidate. The docking study is revealed that all the molecules actively take part in binding to the SARS-CoV-2 RBD Spro and Mpro with their low or high value of binding affinity. This binding of these molecules will help to inhibit the replication of the viral proteins with specific hindrances upon their mutarotation. For both the viral targets, Piperine performed well with its highest binding affinity of −6.4 and −7.3 kcal/mol for SARS-CoV-2 RBD Spro and Mpro, respectively. Besides, Piperine is also found more effective as compared to a few of the currently used drugs. The MD simulation study is supported for the stable interaction of Piperine with SARS-Cov-2 RBD Spro and Mpro. The PCA and binding free energy results also suggest for the active participation of Piperine in stable complex formation with RBD Spro and MPro. Hence, the study proposes Piperine as an active molecule for the inhibition of SARS-CoV-2. Since this study is performed computationally, it requires wet-lab experiments in-vitroas well as in-vivofor further validation.