一株高效生物表面活性剂产生菌的分离、鉴定及培养条件的优化

以市政污水处理厂剩余活性污泥作为菌种来源,经过培养分离、筛选,得到一株高效生物表面活性剂产生菌X1A-2.经形态学与16SrDNA鉴定,X1A-2菌株属于戈登氏菌属.菌株X1A-2产生物表面活性剂的环境影响因素研究结果表明:菌株在发酵培养14h后达到稳定状态,发酵液表面张力降低至33.0mN/m;在较大的培养条件范围内,发酵液的表面张力均可显著降低;石油烃类碳源的存在对其产生物表面活性剂的影响甚微.在模拟石油污染的最优培养条件下,菌株能够长期保持活性,所产生物表面活性剂可使以石油为碳源的发酵液表面张力保持在35mN/m以下.研究结果表明,X1A-2是一株高效生物表面活性剂产生菌,在实际海洋石油污染的生物修复方面具有很好的应用前景.

Isolation,Identification and Culture Conditions Optimization of a High-efficiency Bio-surfactant Producing Bacterium

A high-efficiency bio-surfactant producing bacterium X1A-2 was obtained from bio-trickling filter,in which seeded with waste activated sludge.X1A-2 was identified as Gordonia according to and morphology and 16SrDNA sequence.The experimental results showed that X1A-2 reached the steady state after 14h of fermentation culture,and the surface tension of the fermentation liquor decreased to 33.0mN/m under a large range of conditions.It had little effect on bio-surfactant producing capability when the petroleum hydrocarbon was carbon source.Further investigation showed that X1A-2maintained activity within 30d under the optimum conditions.The surface tension of the fermentation liquor kept below 35.0mN/m.X1A-2 is a high-efficiency bio-surfactant producing bacterium,and it has good prospect of bio-remediation in marine oil pollution.