TITLE:
Antifungal Effects of Lipopeptide Produced by Bacillus amyloliquefaciens BH072
AUTHORS:
Xin Zhao, Zhijiang Zhou, Ye Han
KEYWORDS:
Antifungal Effect, Iturin A, Bacillus amyloliquefaciens, Fusarium oxysporum
JOURNAL NAME:
Advances in Bioscience and Biotechnology,
Vol.8 No.9,
September
19,
2017
ABSTRACT: An
antifungal lipopeptide iturin A with strong activity against Fusarium oxysporum was produced by
honey isolated strain Bacillus
amyloliquefaciens BH072. For large-scale biocontrol application, the antifungal effect was deeply demonstrated by
structure and mode of action. Cyclic
structure and second structure were determined based on situ acid hydrolysis
and Fourier Transformed-Infra Red (FT-IR) Spectra analysis. Structure of α-helix was predicted which might be
associated with activity. Afterwards, antifungal mechanism of iturin A on F. oxysporum were investigated from fungal cell wall to the plasma
membrane and finally to intracellular proteins by morphological, activity of alkaline phosphatase (AKP),
conductivity, Malondialdehyde (MDA) and SDS-PAGE detection. Antifungal damage
appears on not only the spore germination and mycelium growth of F. oxysporum, but also the leakage of
cellular proteins. Moreover, growth
of F. oxysporum could be inhibited in
the presence of iturin A at a MIC of 2.5 mg/mL. Considered with its high
production in previous work, B.
amyloliquefaciens strain BH072 and iturin A might be a promising candidate
for biocontrol.