Review of antiviral medicinal herbs with special emphasis on COVID-19

The Coronavirus disease-2019 (COVID-19) pandemic caused by the severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2). It has engulfed the whole world, and it looks difficult to end this worldwide health crisis without actual medication. Natural products have been utilized since ancient times and have been beneficial over time. The outcome of various research work revealed that pure compounds isolated from medicinal plants, such as Tinospora cordifolia, Withania somnifera, Ocimum sanctum, Glycyrrhiza glabra, Piper longum, Curcuma longa, Allium sativum, Zingiber officinalis, Coriandrum sativum, Azadirachta indica, Emblica officinalis, etc. have excellent Coronavirus (CoV) inhibitory effect. Several molecules, including glabridin, liquiritin, flavonoids, triterpene, glycyrrhizin, aliphatic compounds, sesquiterpenoids, β-sesquiphellandrene, zingerone, β-phellandrene, citral, zingiberene, bisabolene, shogaols, cineol, farnesene, gingerols, withasomniferols A-C, withanone, withasomniferin-A, withasomidienone, withanolides A, linalool, flavonoids, camphor, eugenol, estragole, methyl chavicol, tannins, glycyrrhizic acid, alkaloids, saponins, fatty acids, glycosides, and essential oils, etc. isolated from plants might serve as potential candidates in the treatment of COVID-19.