Targeting novel coronavirus SARS-CoV-2 spike protein with phytoconstituents of Momordica charantia

J Ovarian Res. 2021 Sep 27;14(1):126. doi: 10.1186/s13048-021-00872-3.

Abstract

Background: Infections by the SARS-CoV-2 virus causing COVID-19 are presently a global emergency. The current vaccination effort may reduce the infection rate, but strain variants are emerging under selection pressure. Thus, there is an urgent need to find drugs that treat COVID-19 and save human lives. Hence, in this study, we identified phytoconstituents of an edible vegetable, Bitter melon (Momordica charantia), that affect the SARS-CoV-2 spike protein.

Methods: Components of Momordica charantia were tested to identify the compounds that bind to the SARS-CoV-2 spike protein. An MTiOpenScreen web-server was used to perform docking studies. The Lipinski rule was utilized to evaluate potential interactions between the drug and other target molecules. PyMol and Schrodinger software were used to identify the hydrophilic and hydrophobic interactions. Surface plasmon resonance (SPR) was employed to assess the interaction between an extract component (erythrodiol) and the spike protein.

Results: Our in-silico evaluations showed that phytoconstituents of Momordica charantia have a low binding energy range, -5.82 to -5.97 kcal/mol. A docking study revealed two sets of phytoconstituents that bind at the S1 and S2 domains of SARS-CoV-2. SPR showed that erythrodiol has a strong binding affinity (KD = 1.15 μM) with the S2 spike protein of SARS-CoV-2. Overall, docking, ADME properties, and SPR displayed strong interactions between phytoconstituents and the active site of the SARS-CoV-2 spike protein.

Conclusion: This study reveals that phytoconstituents from bitter melon are potential agents to treat SARS-CoV-2 viral infections due to their binding to spike proteins S1 and S2.

Keywords: Bitter melon; Erythrodiol; Momordica Charantia; SARS-CoV-2; SPR.

MeSH terms

  • Binding Sites / drug effects
  • COVID-19 / genetics
  • COVID-19 / virology
  • COVID-19 Drug Treatment*
  • Humans
  • Hydrophobic and Hydrophilic Interactions / drug effects
  • Molecular Docking Simulation
  • Momordica charantia / chemistry*
  • Oleanolic Acid / analogs & derivatives
  • Oleanolic Acid / chemistry
  • Oleanolic Acid / pharmacology
  • Plant Extracts / chemistry
  • Plant Extracts / pharmacology*
  • Protein Binding / drug effects
  • SARS-CoV-2 / drug effects
  • SARS-CoV-2 / pathogenicity
  • Spike Glycoprotein, Coronavirus / antagonists & inhibitors
  • Spike Glycoprotein, Coronavirus / genetics*
  • Surface Plasmon Resonance

Substances

  • Plant Extracts
  • Spike Glycoprotein, Coronavirus
  • spike protein, SARS-CoV-2
  • erythrodiol
  • Oleanolic Acid