Research On The Isolation Of Crude-oil-degrading Strains And Their Hydrocarbon Degradation Ability

Abstract：With the development of morden petroleum industry,thepollution caused by oil becomes more and more serious. In this work, we isolated of microbial strains for oil degradation from envoironmental samples and their characteristics of those oil-degrading strains were investigated.36strains were isolated from the environmental samples. BLAST of the nucleotide sequence of the16S rRNA gene showed that these isolates belonged to genera Pseudomonas, Acinetobacter, Bacillus, Bordetella, Klebsiella, Microbacterium, Escherichia, Sinorhizobium, Massilia, Stenotrophomonas, Herbaspirillum, Methylobacterium, Bordetella and Micrococcus luteus, respectively.Among the36isolates, strains J42(Massilia timonae,96%), N4(Sinorhizobium,97%), B11(Escherichia hermannii,98%), NY23(Acinetobacter,98%) and NS3(Pseudomonas,97%) show high emulsification activity. The highest rate of emulsification activity of60%for all those strains were observed after5days of cultivation with optimum conditions. At the same time, J42and NS3could reduce the solution surface tension to below40mN/m, while N4, NY23and B11could reduce the solution surface tension to55mN/m. Invstigtion on the contact angles of isolates show temperature and pH value play important roles on bacterial surface hydrophilicity. It was indicated that strain J42and strain B11could degraded almost all aromatic hydrocarbon with5g/L.