Bioinformatics Analysis of Bioactive Compounds of Four Capsicum Species against SARS-CoV-2 Infection

Background: Plant-based remedies against Covid-19 and their research to discover antiviral compounds have been growing rapidly. However, there are little interest to explore and collect information of bioactive compounds of pepper (Capsicum sp.) to fight off the disease. This study aimed to bioinformatically explore and identify bioactive compounds in chili pepper fruits from four Capsicum species (C. annuum, C. baccatum, C. chinense, C. frutescens) which were compatible to fight off SARS-CoV-2 and provide indirect and direct virus inhibition from previous studies. Methods: Protein-ligand interactions were obtained from protein data bank (PDB), PubChem, and SwissModel for homology modeling. Docking was performed using PyRx and visualized using BIOVIA Discovery Studio Visualizer 2016. Results: Four chili pepper species were rich in organic acid compounds (100 times higher than carotenoids concentration; 0.2-156 mg/kg F.W). A type of fatty acids composition in seeds was slightly different from flesh and peels by the small amount of pharmaceutically valuable palmitoleic acids in seeds (approximately 30 mg/kg F.W). Composition of flavonoid relatively varied among the species but luteolin was found in all chili peppers (0.5-18 mg/kg F.W). Most of the compounds were actively interacting with 3CLPro rather than ACE-2 and TMPRSS2 which were well covered up by only 10 and 17 molecules respectively. Conclusion: Four chili pepper species contained bioactive compounds that are medicinally important to fight against SARS-CoV-2 infection.