耐盐菌BF40产表面活性剂特性及其对石油污染盐渍化土壤的修复能力

Biosurfactant Producing Characteristics of a Salt-tolerant BF40 Strain and Its Remediation in Petroleum Contaminated Saline Soil

为强化微生物修复石油污染盐渍化土壤并提供高效产表面活性剂菌种,研究了耐盐菌SerratiaBF40产生物表面活性剂的条件、动力学特征以及对石油污染盐渍化土壤的修复能力。结果表明:BF40产表面活性剂最适碳源为牛肉膏,最适氮源为氯化铵。在30～37℃,pH7.0～9.0范围内产表面活性剂的能力较强。BF40在对数生长期产生表面活性剂,产生方式与细胞生长相关联。在含2.0%NaCl的培养基中,BF40可将发酵液表面张力降低到32.0mN·m-1,EI24达到66.9%。在含盐量为0.22%和0.61%土壤中添加BF40,降解40d后,土壤总石油烃降解率达到50%以上,表明BF40在强化修复石油污染盐渍化土壤中具有很大的应用潜力。

To provide high-efficient biosurfactant-producing bacteria and enhance the bioremediation efficiency of petroleum contaminated saline soil,the biosurfactant-producing conditions and dynamics of a salt-tolerant Serratia BF40 strain and its remediation in petroleum con-taminated saline soil were carried out.Results indicated that the optimum carbon and nitrogen sources for biosurfactant production were beef extract and NH 4 Cl,respectively.BF40 strain could produce more biosurfactant at 30~37 ℃ and pH ranged from 7.0 to 9.0.Biosurfactant was produced during the log phase and producing type was correlated with cell growth.Surface activity of fermentation broth was significantly ef-fective in the presence of 2.0% NaCl,and the value of surface tension and EI24 were 32.0 mN·m-1 and 66.9%,respectively.Petroleum degra-dation experiments showed that BF40 strain could remove more than 50% of total petroleum hydrocarbons after 40 days in the soil with 0.22% and 0.60% salinity.These results indicated that BF40 strain had potential used in bioremediation of petroleum-contaminated saline soil.