RESUMO
OBJECTIVE: In order to study the synergic effect of two marine obligate hydrocarbonoclastic bacteria in the oil biodegradation process. METHODS: We combined the PAHs degrader Marinobacter sp. PY97S with the oil degrader Alcanivorax sp. 22CO-6 and Alcanivorax sp. JZ9B respectively to construct oil-degrading consortia. Multiple methods including weighting method, gas chromatography-flame ionization detection, gas chromatography-mass spectrometry and thin layer chromatography-flame ionization detection were used to analyze and compare the oil degradation rates as well as the chromatographic figures of degraded oil between the pure cultures of obligate hydrocarbonoclastic bacteria and defined consortia. RESULTS: The two consortia, 22CO-6 + PY97S and JZ9B + PY97S, exhibited synergic effects in the oil biodegradation process. The degradation rates of oil by the consortia were increased from 27.81% and 83.52% to 64.03% and 86.89% compared to the pure culture of oil degrader 22CO-6 and JZ9B, respectively. The consortia could degrade aliphatic and aromatic fraction at the same time, including high molecular weight PAHs chrysene and its alkyl derivatives. CONCLUSION: There are obvious synergic effect of Alcanivorax and Marinobacter strains in the oil biodegradation process, which accelerated the oil biodegradation and decomposed thoroughly the more ecotoxic high molecular weight compounds in crude oil.