Quercetin Shows Promise as Targeted Biocontrol Agent Against Pseudomonas syringae

Strategic Insights -

Investigators at Gujarat University in Ahmedabad, India, have been exploring the potential of quercetin as a biocontrol agent against Pseudomonas syringae, a plant pathogen that causes bacterial blight in legumes. Quercetin, a plant-derived compound, has been found to selectively disrupt the quorum sensing (QS) mechanism of P. syringae without affecting beneficial plant growth-promoting bacteria (PGPR). This study aimed to identify plant-derived compounds capable of selectively disrupting the QS of P. syringae, using a combined in silico and in vitro approach.

Key Takeaways:

  • Quercetin exhibited potent, dose-dependent inhibition of violacein pigment in Chromobacterium violaceum biosensor assay, with a docking score of -10.363 kcal/mol and binding energy of -55.89 kcal/mol.
  • Molecular docking and MM-GBSA analyses identified quercetin as the most potent compound, exhibiting strong binding affinity to QS-related proteins in P. syringae.
  • Quercetin inhibited bacterial growth by 90-95% at 1024 mg/mL, with sub-MIC values for P. syringae, K. pneumoniae, and S. meliloti at 156.7, 242.6, and 535.7 mg/mL, respectively.
  • Quercetin suppressed biofilm formation by 92% in P. syringae, 95-98% in K. pneumoniae and S. meliloti, and 78% in C. violaceum at 64 mg/mL.
  • The study highlights quercetin's potential as a targeted biocontrol agent for legume crop protection.

Statistics:

  • 90-95% inhibition of bacterial growth by quercetin at 1024 mg/mL
  • Sub-MIC values for P. syringae, K. pneumoniae, and S. meliloti: 156.7, 242.6, and 535.7 mg/mL, respectively
  • 92% suppression of biofilm formation by quercetin in P. syringae at 64 mg/mL
  • 95-98% suppression of biofilm formation by quercetin in K. pneumoniae and S. meliloti at 64 mg/mL

Sources:

  • Quercetin as a selective quorum sensing inhibitor: in silico and in vitro analyses against Pseudomonas syringae with limited impact on plant growth-promoting bacteria. Molecular Diversity, 2025.
  • Jignesh Prajapati et al. "Quercetin as a selective quorum sensing inhibitor: in silico and in vitro analyses against Pseudomonas syringae with limited impact on plant growth-promoting bacteria." Molecular Diversity, 2025.
  • Gujarat University, Ahmedabad, India
  • Springer, Van Godewijckstraat 30, 3311 Gz Dordrecht, Netherlands (publisher of Molecular Diversity)