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期 刊 ：植物保护学报 2008年

关键词：枯草芽孢杆菌；抑菌物质；表面活性素；分离；结构测定；

Keywords:Bacillus subtilis, antagonistic substance, surfactin, isolation, structure analysis,

摘 要 ：为明确生防菌株Bacillus subtilis SN-02产生的抑菌物质的种类和组成,对其进行分离、纯化及结构测定。发酵滤液经盐酸沉淀,有机溶剂提取,薄层层析显色分析,初步确定该活性物质是一种具有闭合肽键的脂肽类物质。经Pharmadex LH-20 精制后得到纯度为95.7%的淡黄色结晶状物质,液质联用检测到活性成分是分子量为1080、1035和1021D的生物表面活性素。紫外吸收光谱表明该物质在210nm处有吸收峰,红外吸收光谱证实该分子的亲水基是一条肽链,疏水基部分是一脂肪酸分子,且为一种环状脂肽类物质。氨基酸分析表明该活性物质由4种氨基酸组成,且4种氨基酸的摩尔比为Glu∶ Leu∶ Val∶ Asp=1∶ 4∶ 1∶ 1。

Abstract:Isolation, purification and structure analysis of the antagonistic substance produced by Bacillus subtilis SN-02 was studied to ascertain its chemical component. It was isolated and purified from the fermented culture with methods of acid precipitation, solvent extraction and analysised by thin-layer chromatography. The results showed that the antagonistic substance was a kind of lipopeptide with a cyclic structure. The light yellow crystal of biosurfactin obtained with Pharmadex LH-20 gel filtration column chromatography and analysis of high pressure liquid chromatography showed that the purity of it was 95.7%. Liquid chromatography coupled with mass spectrometry analysis indicated the lipopeptide are homologues of surfactin, with a molecular weight of biosurfactin of 1080, 1035 and 1021D, respectively. UV absorption spectrum showed that biosurfactin has absorption peak at 210nm. Infrared absorption spectrum confirmed that its hydrophilic part is a peptide chain and hydrophobic part is fatty acid. With the amino acid composition analysis, the hydrophilic moiety is consisted of Asp, Leu, Glu, Val with a mole ratio of 1∶ 4∶ 1∶ 1.

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