石油降解菌群的筛选、构建及其降解特性研究

Isolation and construction of petroleum-degrading flora and their degrading characteristics

为了构建高效石油降解混合菌群,从潜江某油田采集8个石油污染土样(分别记为S1~S8)和2个石油污染水样(分别记为W3、W4),以石油为唯一碳源进行富集驯化培养;采用外观评分、石油降解率、石油3组分降解率、饱和烃中正构烷烃色谱分析等方法筛选石油降解优势菌群,构建石油降解混合菌群;采用正交试验研究混合菌群最佳降解条件。结果表明,富集的10个石油降解菌群中S3、S4、S5、S6、S8为优势菌群,培养30d后的石油降解率分别为21.67%、22.34%、27.23%、20.46%、19.99%;菌群W3、W4对石油乳化效果较好;混合菌群M3(S3+S4+S5+S8+W3+W4)为石油降解优势混合菌群,其最佳降解条件为35℃、pH7.60、含油率1.70%,在最佳条件下培养30d后,混合菌群M3对石油降解率达30.71%,比最优菌群S5的石油降解率提高了12.78%。

In order to construct high efficient petroleum-degrading flora, eight oil-contaminated soil samples （signed S1-S8） and two oil-contaminated water samples （signed W3 and W4） were collected from an oil field in Qian Jiang. Taking petroleum as the sole carbon source, the enrichment and domestication were carried out to obtain the flora,and finally the flora with good petroleum-degrading performance were screen by scoring criteria of appearance, petroleum removal rate and gas chromatographic. The predominant petroleum-degrading flora were applied to con- structed mixed flora. The oil degradation characteristics of mixed flora were studied by orthogonal experiment. The results showed that five bacteria of 83,84, S5,S6, S8 displayed the perfect petroleum removal efficiency, the petroleum degrading rate was 21.67% ,22.34%,27.23% ,20.46% and 19.99% respectively after 30 d of culture. The mixed bac teria M3 （S3＋S4＋S5＋S8＋W3＋W4） was the superior mix flora for petroleum degrading, the oil removal rate reached 30.71% in 30 days at optimal growth conditions of 35 ℃ ,pH 7.60,oil content 1.70%. It was 12.78% higher than that of superior flora S5.