含油污泥中石油降解菌的分离及其降解特性

从渤海油田含油污泥中分离出3株石油烃降解菌,通过16S rRNA基因序列鉴定RS1、RS2和RS3分别为棒状杆菌、短杆菌和假单胞菌。经单因素实验确定,3株细菌对石油的最适降解条件分别为37℃、盐度3%、pH 8;32℃、盐度1%、pH 8;42℃、盐度1%、pH 6。降解实验结果表明,3株细菌30 d内对含油污泥中总石油烃的降解率分别为39.69%、31.13%和53.29%,而混合菌的降解效果明显高于单一菌株,降解率为58.08%;不同菌株对原油中不同组分的降解能力不同,其中,RS1对饱和烃的降解率最高,达20.74%,RS3对芳香烃的降解率最高,达到8.08%;GC-MS分析表明,混合菌对n-C12~n-C34等正构烷烃均有明显降解,且对萘、苊、屈和苯并[b]荧蒽等多环芳烃的降解能力较强。

Isolation of petroleum hydrocarbon degrading bacteria from oily sludge and its degrading characteristics

Three bacteria strains,RS1,RS2 and RS3,were isolated from petrochemical oily sludge of Bohai Sea Oilfield (Tianjin,China) and identified as Corynebacterium sp.,Brevibacterium sp.,and Pseudomonas sp.through 16S rRNA sequence similarity search.The optimum degradation conditions of three bacteria were studied by single factor experiment,and the results were 37℃,salinity 3%,pH 8;32℃,salinity 1%,pH 8;42℃,salinity 1%,pH 6,respectively.The degradation results showed that the degradation rates of TPH in oily sludge by RS1,RS2 and RS3 were 39.69%,31.13% and 53.29%,and the effect of mixed bacterial cultures,with a degradation rate of 58.08%,was significantly better than the single bacteria.The degrading ability of bacteria vary with oil component.RS1 had the best degradation effect on aliphatic hydrocarbon,its degradation rate was 20.74%;and RS3 had the best degradation effect on aromatic hydrocarbon,and its degradation rate was 8.08%.GC-MS analysis showed that n-C12~n-C34 n-alkanes were significantly degraded by mixed bacteria,which have strong degradation capacity with PAHs including naphthalene,acenaphthene,chrysene and benzo[b] fluoranthene.