Inhibitory effect of the lipopeptide extract from Bacillus amyloliquefaciens B17 on the mycelial growth and spore germination of Gilbertella persicaria

Bacillus species are of great interest due to their ability to produce lipopeptides with antifungal properties against various plant pathogenic fungi. The aim of this study was to evaluate the inhibitory effect of a lipopeptide extract from Bacillus amyloliquefaciens B17 on the mycelial growth and spore germination of the fungus Gilbertella persicaria, as well as to identify the compounds responsible for the antifungal activity. Scanning electron microscopy revealed that the lipopeptide extract caused abnormal bulges in the hyphae and malformations in the germ tubes. Additional analyses showed increased permeability in both the mycelium and spores, attributed to the action of the lipopeptides. Thin-layer chromatography (TLC) combined with mass spectrometry (ESI-MS) identified a total of eleven homologs corresponding to fengycin A, fengycin B, bacillomycin D, and surfactin in the extract. These findings suggest that the lipopeptide extract from B. amyloliquefaciens B17 represents a promising tool for the biological control of G. persicaria.