Antifungal activity of novel indole derivative from endophytic bacteria Pantoea ananatis 4G-9 against Mycosphaerella musicola

ABSTRACT

An endophytic bacterium isolated from banana G-9 (AAA genotype) leaves exhibited strong antagonistic activity against Mycosphaerella musicola. The isolate was identified as Pantoea ananatis 4G-9 by 16S rRNA sequence analysis. Secondary metabolite obtained from P. ananatis 4G-9 was found to have antifungal activity. The active compound was purified from crude extract using column chromatography. Purity of the active compound was assessed using high-performance liquid chromatography. Spectral analysis of compound using infrared, mass spectrometry and nuclear magnetic resonance indicated that the compound structure is an indole derivative. The compound showed strong and dose-dependent antifungal activity against M. musicola. This is the first report on P. ananatis isolated as an endophyte from banana leaves and its antifungal activity against M. musicola.

KEYWORDS:

• Bacterial metabolite
• indole derivative
• Pantoea ananatis 4G-9
• Mycosphaerella musicola
• secondary metabolite

Acknowledgements

We thank for DST-PURSE program for providing the HPLC system (Shimadzu Scientific System, India).

Funding

The authors are thankful to the University of Mysore and University Grant Commission, New Delhi for providing UGC-NONNET fellowship for the first author.