石油高效降解菌的筛选及其降解特性

Screening of highly efficient petroleum-degrading bacteria and their biodegradation characteristics

从石油污染土壤中筛选、分离得到三株高效石油降解菌GX1、GX2、GX3,初步鉴定分别为假单胞菌属(Pseudomonas sp.)、邻单胞菌属(Plesionmonas sp.)和动胶菌属(Zoogloea sp.).同时还研究了pH值、营养物质、油质量浓度对菌体生长和降油率的影响.结果表明,这三株菌在初始pH值为7-9对石油的降解率分别为86.7%,72.9%,64.7%;最佳氮源为NH4NO3,氮磷比大约控制在4∶1左右时,降解效果较好.在原油初始浓度较低时,降解率随石油浓度的升高而略有提高.不同菌株耐油程度不同.

Three strains of bacteria, identified as Pseudomonas sp. （GX1）, Plesionmonas sp. （GX2） and Zoogloea sp. （GX3） ,for degrading oil with high efficiency were isolated from oil-contaminated soil. And the optimum ecological conditions for their degrading were studied by changing the pH value,the nutrients and the mass concentration of the oil. The testing results show that if the pH value was in the range of 7 to 9,the biodegrading efficiency of the three strains can reach to 86.7% ,72.9% and 64.7% respectively. The ammonium nitrate（NH4NO3）was demonstrated as the optimum nitrogen source and the optimum ratio of nitrogen over phosphorus was 4 over 1. The degrading efficiency will increase a little with the increasing of the oil concentration under low initial oil concentration. Different strains have different degrees of oil tolerance.