Properties study and phylogenetic analysis of a bacterial strain with high de-emulsification efficiency

For further practical application,the phylogenetic analysis and de-emulsification properties study of strain XHl with high de-emulsification efficiency isolated from crude oil contaminated soil in Daqing oil field were conducted with a surfactant-stabilized water-kerosene model emulsion.The factors infuencing the de-e-mulsification efficiency and the generation site of de-emulsification active component of the strain were also in-vestigated.The similarity of 16SrDNA sequences between strain XHI and Bacillus mojavensis (DQ993678)was 99%.According to the physiological biochemical test,strain XHl was preliminarily identified as Bacillus mojavensis. The logarithmic growth,stable phase and decline phase of strain XHl were determined as 14.18 and 28 h,respectively-The best de-emulsification activity emerged after cultivating for 18h,and the complete de-emulsification Was achieved at 24 h.The most favorable incubation conditions for de-emulsification occurred metabolites.The above results indicate that strain XHl has high de-emulsification efficiency and is potential as a commercial de-emulsifier.