堆肥中生物表面活性剂脂肽产生菌的筛选

Isolation of Lipopeptide Bio-surfactant-producing Bacteria from Compost

从农业堆肥样品中提取出4株可将发酵液的表面张力降到40mN/m以下的菌株,对该四株菌的发酵液进行薄层层析(TLC)分析,结果表明其中3株产生的生物表面活性剂可能为脂肽。选取其中一株B2对其所产的生物表面活性物质进行提纯,经过红外光谱(FT-IR)分析,证明该产物为一环脂肽类似物。该脂肽纯品可将纯水的表面张力由72.3mN/m降到29.9mN/m,CMC值为0.139g/L。实验结果表明,堆肥过程中存在能够产生生物表面活性剂脂肽的菌种,且具有良好的表面活性。

Four microorganisms have been obtained from samples of agricultural compost, which are characterized by capabilities of depressing the surface tension of fermentation liquor to less than 40mN/m, among other things, three might produce lipopeptide according to the analysis by TLC. The further research on Strain B2 involves purifying its bio-surfactant and the analysis using FT-IR, resulting in identification of the biosurfactant as a cyclic lipopepfide analogue. It has been also showed that pure lipopepfide can depress surface tension of pure water. As a result, bio-surfactant-producing microorganisms are obviously produced during the composfing process of agricultural wastes, which have a fairly good surface activity.