ABSTRACT

Today, the coronavirus epidemic, which caused the death of 79 million cases and 1743 thousand people in 218 countries around the world, continues to increase its impact all over the world. Researchers are still trying to develop an effective solution against covid-19, including vaccines and drugs. However, there are few studies that determine the effect of natural products obtained from plants on covid-19. Medicinal and aromatic plants have been used for therapeutic purposes since the existence of humanity. In this study, the effects of some important medicinal plants including Licorice (Glycyrrhiza glabra), Saffron (Crocus sativus L.), Nigella (Nigella sativa L.), Laurel (Lauris nobilis), Karabaş (Lavandula stoechas), and Zahter (Thymbra spicata L. var. Spicata) against Covid-19 were investigated in vitro conditions. The six plants were evaluated for cytotoxic effect on Vero cells and determining inhibition of viral replication in Vero-E6 cells at concentrations of broad-spectrum antiviral non-cytotoxic against Covid-19 in cell culture and an additional antiviral effect against Covid-19. According to the results, the five examined plants (Saffron, Nigella, Laurel, Karabaş, Zahter) were ineffective against Covid-19 in vitro conditions. Interisingly, the water extract obtained from the root of the licorice plant (Glycyrrhiza glabra) inhibited Covid-19 in vitro conditions in the 2nd dilution (1: 4) following the initial concentration in Vero-E6 cells.