Molecular docking of bioactive compounds of nut grass (Cyperus rotundus L.) tuber against SARS-CoV-2

Coronavirus Disease-2019 (COVID-19) is a novel coronavirus infection that causes severe acute respiratory syndrome 2 (SARS-CoV-2). Compounds with therapeutic potential for this disease are still being investigated, ranging from approved medications to natural compounds. Nut grass (Cyperus rotundus L.) is a plant that has been reported to have antiviral activities against several types of viruses, however, there have been no reported studies on its tuber antiviral activity against SARS-CoV-2. The purpose of this study was to evaluate the potential antiviral activity of nut grass tubers by applying an in silico approach against the SARS-CoV-2 main protease (Mpro) and spike (S) glycoproteins. Methanol and n-hexane were used to extract the bioactive compounds, which were then analyzed using Gas Chromatography-Mass Spectrometry (GC-MS). The analysis resulted in the identification of 177 probable compounds in methanolic extract and 144 compounds in n-hexane extract. These compounds' anti-SARS-CoV-2 activity was determined using molecular docking with B-d-N4-hydroxycytidine (NHC) (a metabolic product of molnupiravir) as a control ligand. Furthermore, the bioactivity of these compounds was assessed using SwissADME, admetSAR, and PASS Online. This study showed that 7-Hydroxy-6,9a-dimethyl-3-methylene-decahydro-Azuleno[4,5-b]furan-2,9-dione (from methanolic extract);Androstan-17-one,3-ethyl-3-hydroxy,(5a)-(from methanolic extract);2-[4-methyl-6-(2,6,6-Trimethylcyclohex-1-enyl)hexa-1,3,5-Trienyl]cyclohex-1-en-1-carboxaldehyde (from methanolic and n-hexane extracts);2-Vinyl-9-[3-deoxy-ß-d-ribofuranosyl]hypoxanthine (from methanolic extract);and Pregan-20-one, 2-hydroxy-5,6-epoxy-15-methyl-(from methanolic and n-hexane extracts) have best binding affinity and interacted with important amino acid residues at the Mpro and S glycoprotein receptors. The findings of this study indicate that these compounds have the potential to be studied further as antiviral against SARS-CoV-2. © 2023 Author(s).