Determination of wax removal and viscosity reduction in crude oil treated by dominant bacteria

Five paraffin-degrading bacteria were isolated from petroleum-contaminated soil collected from Liaohe Oilfield, from which a dominant strain named SS13 was screened out via D2O-labeled single-cell Raman spectroscopy. The dominant strain was identified asStenotrophomonas maltophilia, and its potential effect in the biodegradation of crude oil was investigated. Results show that the strain produces a biosurfactant which has an emulsification effect on liquid paraffin, and the emulsification index is 65%. The crude oil after incubation with SS13 shows the rates of the wax removal and viscosity reduction reach 74.36% and 47.83%, respectively.