In silico Studies of Black Cumin (Nigella sativa) Essential Oils as Potential Prophylactic Treatment Against COVID-19

A global challenge in many sectors including health and disease management, is posed by the rapidly spreading coronavirus disease 2019 (COVID-19). This research serves as a preliminary investigation by screening potential compounds from Nigella sativa essential oils that may perform as COVID-19 prophylaxis by a set of in silico studies, including chemical characterization, ADMET prediction, molecular docking, density functional theory, and gene enrichment analysis. Through molecular docking, 117 candidate compounds were collectively predicted for their inhibitory effects against crucial protein targets (Mpro, PLpro, Nucleocapsid, Spike, TMPRSS2 and ACE2). DFT analysis was performed to examine the degree of reactivity of the 10 best performing compounds. In addition, a gene enrichment analysis was conducted to gain insight on the modulation of relevant genes and pathways in relation to COVID-19 and the immune system. Together, the study has revealed a number of promising compounds including cyclododecene, a-phellandrene, a-pinene, terpinolene limonene, eucalyptol and allo ocimene which are predicted to possess good inhibition activity towards target proteins and the ability to modulate relevant genes including, GAPDH, HMOX1, and NFE2L2. Overall, this study proposed that the prophylactic effect may be achieved by 2 mechanisms, by immune system enhancement and suppression of proinflammatory cytokines