Abstract:

In order to study the effect of microbe remediation on soil contaminated by petroleum, three strains of petroleum degrading bacteria were isolated from contaminated soil in Daqing oil field, which was named No.18, H and 21 strains, which can use oil as the carbon nutrition for their growth. These three bacterium species had been clearly identified by using morphological and molecular biological methods as micro-bacterium, arthrobacter and bacillus. Single factor test design was used to test the strain growth conditions in inorganic salt medium including pH, salt concentration, nitrogen, phosphorus and other factors. The results showed that the optimum growth conditions was pH=7, NaCl concentration of 3% for strain H, and pH=8, 3% salt for No.18 strain as well as pH=7, NaCl concentration of 1% for No.21 strain. The best nitrogen source was KNO3 for H strain, NH4NO3 for No.18 strain and NH4Cl for No.21 strain. The most suitable phosphorus source was K2HPO4:KH2PO4 with the rate 1:2.for No.18 strain, and K2HPO4.for both of No.18 and No.21 strains.