生物表面活性剂产生菌的分离培养及其产物特性研究

从加油站受石油污染的土壤中分离到1株高效产生物表面活性剂的菌株,经鉴定为气生单孢菌(Aeromonas sp.)。并对其发酵液表面活性剂性能及稳定性进行分析,最佳条件下发酵液的表面张力可由70.2 mN/m 降至28.9 mN/m,对温度、pH、矿化度有较好的稳定性,维持85 %以上油水乳化液稳定时间达到350 h。对其发酵条件进行了优化,确定表面活性剂产生最适C源为2 %甘油,以硝酸盐和铵盐作为N源对表面活性剂产生无影响。对其产生物表面活性剂进行提纯,经TLC分析初步确定该表面活性剂为糖脂类化合物。

ISOLATION OF BIOSURFACTANT PRODUCING BACTERIA AND CHARACTERISTICS OF THE BIOSURFACTANT

A strain of bacteria able to produce biosurfactant was isolated from oil-polluted soils. It was identified as Aeromonas sp.. The biosurfactant in fermentation broth was able to reduce the surface tension of water from 70.2mN/m to 28.9mN/m and showed great stability against temperature, pH and mineralization. The biosurfactant could stabilize the broth over 85% for 350h. The optimal carbon source for fermentation of the biosurfactant was 2.0% glycerol..NO3- or NH4- as nitrogen source had no difference for biosurfactant production. The biosurfactant was extracted from fermented broth and analysed by TLC. Analytic results showed that this biosurfactant was a kind of glycolipid.