Molecular docking studies of Ocimum americanum secondary metabolites against SARS-Cov-2 spike protein


  • Vijayalakshmi K.
  • Gayathri Gunalan
  • Balabhaskar R.



S protein, Corona virus, Kanjankorai, ADME properties, Lopinavir, Phytochemicals


Introduction and Aim: The outbreak of Covid-19 pandemic since December 2019 has raised serious global health concern. Because of rapid human to human transmission and non-availability of clinically proven drugs or vaccines, this Covid-19 pandemic has created a great threat to mankind. Many naturally derived molecules are being investigated for the treatment of Covid-19. Ocimum americanum is one such significant medicinal plant possessing a variety of biological activities.


Materials and Methods: In the present study, seven phytochemicals were selected from O. americanum and were docked against SARS-CoV-2 spike protein which is an important site for virus to enter the host cell. Docking was performed using Autodock Vina and the ADME properties of all these seven ligands were predicted using the Swiss-ADME tool. The bioactivity score was also predicted using the Molinspiration tool. Besides the secondary metabolites, all these analyses were also performed for well-known antiviral drugs namely lopinavir and ritonavir.


Results: The binding energy obtained from the docking studies of SARS-CoV-2 spike protein with Lopinavir, Ritonavir, Alpha-farnesene, Beta-farnesene, Eugenol, Linalool, Estragole, Limonene and 1,8-Cineole was found to be -5.2, -5.1, -4.7, -4.5, -4.3, -4.1, -4, -3.9 and -3.8 Kcal/Mol respectively. Swiss-ADME results also suggest that all the selected ligands follow the drug likeness properties and hence they could be taken for further drug discovery process.


Conclusion: From the present in silico study, it can be concluded that secondary metabolites of O. americanum have potential inhibiting activity against spike protein of SARS-CoV-2. Isolation and efficacy studies in vitro may provide an insight into the drug discovery to fight Covid-19.

Author Biographies

Vijayalakshmi K.

Ponmana Chemmal Puratchi Thalaivar MGR Govt Arts and Science College, Sirkali, 609 108, Tamil Nadu, India

Gayathri Gunalan

Siddha Regional Research Institute (Central Council for Research in Siddha, Ministry of Ayush, Govt. of India), Kuyavarpalayam, Puducherry, 605 013, India

Balabhaskar R.

PrimeGen Healthcare Laboratories Private Limited, Nanganallur, Chennai, 600 061, Tamil Nadu, India


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How to Cite

K. V, Gunalan G, R. B. Molecular docking studies of Ocimum americanum secondary metabolites against SARS-Cov-2 spike protein . Biomedicine [Internet]. 2023 Feb. 26 [cited 2024 Mar. 3];43(1):94-103. Available from:

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