| Bacillus subtilis strain BAB-1 was isolated from rhizospheric soil and showed strong inhibition against Botrytis cinerea. The cultural supernatant of strain BAB-1 displayed significant control efficiency against tomato grey mold on field condition.Lipopeptides were isolated from the cultural supernatant of Bacillus subtilis strain BAB-1 by the methods of hydrochloric acid precipitation and methanol extraction. The extract showed an effective inhibitory activity against a wide range of phytopathogenic fungi and inhibited mycelial growth and conidia germination of B. cinerea. The lipopeptides were stable to high temperature, different pH value, several proteinases and commonly used organic solvents.The lipopeptides were purified by FPLC, and three fractions were harvested, designated as LP-1, LP-2 and LP-3. LP-1 showed a similar retention time to the standard sample of surfactin in FPLC and TLC analysis. Therefore, LP-1 was preliminarily considered to be surfactin. ESI-MS analysis of the LP-1 revealed 3 [M+H]+ ion peaks at m/z1009.0, m/z 1023.1, m/z 1037.1 respectively, which were in agreement with the 3 homologous compounds of the standard surfactin. Specific PCR amplification of the sfp gene fragment confirmed the existence of the surfactin biosynthetic genes in strain BAB-1. LP-2 was determined as fengycin by MALDI-TOF-MS analysis. LP-3 was undetermined.Fengycin showed strong inhibition against Botrytis cinerea, while surfactin had no antifungal activity. However, the addition of surfactin enhanced the antibiotic activity of fengycin. Interaction of surfactin and fengycin may explain the synergistic effect of surfactin on the biological properties of fengycin.Crystals of surfactin and fengycin appeared a cruciate structure under light microscope. Surfactin isolated from the cultural supernatant of Bacillus subtilis strain BAB-1 could reduce surface tension of water remarkably, also it had hemolytic and oil expansion activities.
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