MacElwee C G, Lee H, Trevors J T
Department of Environmental Biology, University of Guelph, Ontario, Canada.
J Ind Microbiol. 1990 Jan;5(1):25-31. doi: 10.1007/BF01569603.
Twenty-three bacterial strains were isolated from oil-contaminated soil samples. Of these, 20 displayed some ability to effect oil dispersion and they were screened quantitatively for the ability to emulsify 0.5% (v/v) reference oil. One strain, identified as Pseudomonas aeruginosa UG1, produced extracellular material that emulsified reference oil, hexadecane and 2-methylnaphthalene at concentrations as high as 6% (v/v) in nutrient broth. Emulsification activity increased during a 10 day incubation period at 30 degrees C. The activity was not influenced by pH over the range 5 to 9. The emulsifying agent was precipitated by cold ethanol. The highest emulsifying activity was detected in the extracellular fraction precipitated between 30 and 50% (v/v) ethanol. A linear relationship was observed between emulsifier concentration (mg/ml) and emulsifying activity. Genetic analysis showed that the Pseudomonas aeruginosa UG1 strain did not carry extrachromosomal plasmids, suggesting that the gene(s) coding for emulsifying activity was carried on the chromosome.
从受油污染的土壤样本中分离出23株细菌菌株。其中，20株表现出一定的使油分散的能力，并对它们乳化0.5%（v/v）参比油的能力进行了定量筛选。一株被鉴定为铜绿假单胞菌UG1的菌株产生了能在营养肉汤中乳化高达6%（v/v）参比油、十六烷和2-甲基萘的胞外物质。在30℃下孵育10天期间，乳化活性增加。在pH值5至9范围内，该活性不受影响。乳化剂可被冷乙醇沉淀。在30%至50%（v/v）乙醇沉淀的胞外组分中检测到最高乳化活性。观察到乳化剂浓度（mg/ml）与乳化活性之间存在线性关系。基因分析表明，铜绿假单胞菌UG1菌株不携带染色体外质粒，这表明编码乳化活性的基因位于染色体上。
