Abstract:[Background] Lipopeptides are the antifungal substances ubiquitous in bacteria of Bacillus. Bacillus amyloliquefaciens JDF630 exhibits remarkable antifungal properties, yet the specific compounds responsible for the antifungal properties remain unidentified. [Objective] To determine the antifungal activity and identify the components of lipopeptides produced by B. amyloliquefaciens JDF630. [Methods] The crude lipopeptides were extracted from strain JDF630 by a combination of acid precipitation and methanol extraction. The antifungal activity, broad-spectrum capability, and stability of these lipopeptides were assessed by a modified Kirby-Bauer method. Subsequently, silica gel column chromatography was utilized for separation and purification of lipopeptides. LC-MS/MS was employed to pinpoint the most effective components. [Results] The crude lipopeptides from B. amyloliquefaciens JDF630 potently inhibited six plant pathogens, especially Alternaria tenuissima. Furthermore, these lipopeptides demonstrated remarkable stability across a wide range of temperatures, pH levels, ultraviolet radiation, and proteinase exposure. LC-MS/MS results confirmed that the primary components of these lipopeptides were iturin and surfactin. [Conclusion] This study comprehensively elucidates the antifungal properties and components of lipopeptides from B. amyloliquefaciens JDF630, establishing a robust theoretical basis for the potential applications and future genetic modification of this strain.
