Pseudomonas entomophila 23S Produces a Novel Antagonistic Compound against Clavibacter michiganensis subsp. michiganensis, a Pathogen of Tomato Bacterial Canker

Biopesticides, which consist of antagonistic microorganisms, or the bioactive compounds they produce offer attractive alternatives to synthetic agrochemicals as a means reducing plant diseases in crop production systems. In our previous study, strain Pseudomonas entomophila 23S was reported have strong activity toward Clavibacter michiganensis subsp. (Cmm), pathogen tomato bacterial canker disease, causes serious damage industry. This study focused on purification and characterization anti-Cmm compound(s) produced by P. 23S. The cell-free supernatant first subjected butanol extraction, fractioned solid-phase extraction (SPE), purified high-performance liquid-chromatography (HPLC). semi-preparative retained activity. These were then characterized liquid chromatography coupled with high-resolution tandem mass spectrometry (LC-HRMS/MS) nuclear magnetic resonance (NMR). Two compounds, C15H16N2O C16H18N2O, isolated this procedure. From LC/MS spectra, predicted an isoquinoline ring, presence confirmed NMR. differed respect methyl group side chain. addition, grown different culture media greatest amounts these when Nutrient Broth (NB), where growth slowest. NB composition is more favorable stimulating higher compounds.