Enhancement of rhamnolipid biosurfactant for biodegradation of petroleum hydrocarbons in water

Four bacterial strains (X1, X2, X3 and X4)using diesel oil as sole carbon source were screened from soil, which was polluted by oily wastewater, and they were identified as Serratia sp., Acinetobacter sp., Bacillus sp. and Azomonas sp., respectively. After strain X4 was cultured for 28 d with a rotary shaker at 32°C, the degradation rate of diesel oil by the strain reached 62% and also the biodegradation of diesel oil was significantly enhanced …