Control of rice bacterial leaf blight by antibacterial substances from Lysobacter antibioticus strain 13-1

Abstract:

[Objective] To clarify the antibacterial activity of Lysobacter antibioticus strain 13-1 against rice bacterial blight. [Methods] Four antibiotic compounds were isolated from the fermentation extracts of the strain 13-1 by sephadex LH-20 column chromatography, reverse C-18 Silica gel and high performance liquid chromatography (HPLC). [Results] These purified compounds were identified as 6-Methoxy-1-phenazinol-10-oxide, Phenazine, 1-Phenazinecarboxylic acid and 1-Hydroxy-6-methoxyphenazine by nuclear magnetic resonance (NMR), ESI-Mass spectrum analysis. Four phenazine analogs strongly inhibited mμLtiple Xoo strains growth. The protective efficacy of strain 13-1 was above 60% in field plot compared to controls. [Conclusion] The antimicrobial substances of strain 13-1 was phenazine substances that have the inhibition potential against rice bacterial blight.