Bacillus subtilis 3512A, a marine bacterium, was isolated from Pacifigorgia sp. in South China Sea. The strain showed significant antagonistic activities against many pathogens. The crude anti-fungal extract was stable against high temperature and acid, whereas the antifungal activity reduced notably when pH value is higher than 10. Bioassay-directed fractionation using acid precipitation, flash chromatography and HPLC led to the isolation and purification of two pure metabolites. Oil-film collapsing, emulsification of toluene and on-plate hydrolysis experiments showed the two compounds are cyclic peptides.~1H-NMR experiment confirmed both of them were lipopeptide derivatives.%海洋枯草芽孢杆菌Bacillus subtilis菌株3512A分离自中国南海柳珊瑚.抗菌谱研究表明,该菌对多种动植物病原菌都有很强的抑制作用.稳定性试验表明该菌株产生的抗真菌活性物质对高温、酸和弱碱具有一定耐受性.利用玉米纹枯病菌Rhizoctonia solani作为靶标菌,结合酸沉淀、快速柱色谱、HPLC等现代色谱手段,对菌发酵液中的抗真菌活性物质进行分离纯化,获得两个活性强的单一化合物,化合物1和3.排油圈试验、甲苯乳化试验、TLC原位酸水解,以及一维核磁共振氢谱~1H-NMR等多种研究结果表明,化合物1和化合物3均为脂肽类化合物衍生物.
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