Inhibitory Effect of Phytochemicals from Azadirachta indica A Juss. and Tinospora cordifolia (Thunb.) Miers against SARS-CoV-2 Mpro and Spike Protease- An In Silico Analysis (preprint)

ABSTRACT

COVID 19 caused by SARS-CoV-2 is spreading worldwide and affected 10 million people with a mortality rate between 0.5 % to 5%. Medicinal plants from China, Morocco, Algeria, Africa and India were tested for antiviral efficacy in SARS-CoV-2. Ayurveda Medicine described many medicinal plants. The Nimba (Azadirachta indica A. Juss) is used in fever, bacterial and viral infections, and Amrita (Tinospora cordifolia (Thunb.) Miers) is used as antiviral, antipyretic, and anti-inflammatory purposes. The combination of both these plants is called Nimbamritam, and it is widely used in pyrexia, dermatitis, viral infections, etc. Spike protease (PDB ID 6VXX) and Mpro (PDB ID 6LU) were retrieved from RCSB and 16 ligands from A. indica and 6 ligands from T. cordifolia were obtained from IMPPAT and PubChem. AutoDock Vina embedded PyRx was used for docking. Remdesivir was taken as a reference drug. In silico study of Cordifolide A of T cordifolia showed the highest scores with -8.2 Kcal/mol and -10.3Kcal/mol with Mpro protease and Spike protease respectively. Cordifolide A had 4 H bonds and Kaempferol had 7 non-conventional bonds, including van der Waal with Mpro (6LU7) protease. The interactions with 6VXX had 5 H bonds in each ligand Cordifolide A and Azadirachtin B. The prevention of virus entry by targeting spike protease host receptor ACE2 and restricting replication of the viral genome by targeting Mpro residues were identified in our study. A. indica and T. cordifolia are promising therapeutic agents in COVID 19.