Anti-SARS-CoV-2 potential of castor oil plant () leaf extract: virtual evidence.

L. is a medicinal plant that displays valuable pharmacological properties, including antioxidant, antimicrobial, analgesic, antibacterial, antiviral and anti-inflammatory properties. This study targeted to isolate and identify some constituents of leaves using ultra-performance liquid chromatography coupled with mass spectroscopy (UPLC-MS/MS) and different chromatographic techniques. anti-MERS and anti-SARS-CoV-2 activity for different fractions and for two pure isolated compounds, lupeol (RS) and ricinine (RS1) were evaluated using a plaque reduction assay with three different mechanisms and IC based on their cytotoxic concentration (CC) from an MTT assay using Vero E6 cell line. Isolated phytoconstituents and remdesivir are assessed for anti-COVID-19 activity using molecular docking tools. The methylene chloride extract showed pronounced virucidal activity against SARS-CoV-2 (IC = 1.76 μg/ml). It was also shown that ricinine had superior potential activity against SARS-CoV-2, (IC = 2.5 μg/ml). Lupeol displayed the most potency against MERS, (IC = 5.28 μg/ml). Ricinine appeared to be the most biologically active compound. The study showed that and its isolated compounds have potential natural virucidal activity against SARS-COV-2; however, additional exploration is necessary and study for their activity.