The Study On The Degradation And Application Of The Oil-degrading Strains

The petroleum hydrocarbon contamination of the environment is a serious threat to the health of human and ecosystem. Bioremediation as a potentially effective and low-cost treatment has become a promising option of hydrocarbon contamination. Because the petroleum hydrocarbon is a kind of complicated mixture, and pure bacteria can only metabolize the petroleum hydrocarbon in the limited range, an option to enhance the biodegradation rate and extent of hydrocarbons is to find a bacterial consortium with overall broad enzymatic capacities to degrade complex hydrocarbon mixture. Bacterial consortium has become an effective option in dealing with petroleum pollution because of its higher degradation rate,faster speed and more steady effect. Biodegradation of petroleum hydrocarbon compounds by bacterial consortium was studied in this paper.A bacterial consortium consisting of seven members(named as B4-1,B4-2,B4-3,B4-4,B4-5,B4-6,B4-7)was obtained by a soil enrichment procedure using diesel fuel as carbon source. The former five of them can degrade the petroleum hydrocarbon tested while the last two can not.The degradation effect of the bacterial consortium B4 is better than any constituting pure bacterial strain, with the degrading rate is up to 90.4%. The consortium is well able to bear high salinity and degradation rate remain 69.8~90.1% when the salinity is up to 3.0~3.5%. So the consortium can be applied to the bioremediation of the petroleum hydrocarbon polluted seawater. The experimental result of the influence of the initial diesel oil concentration and inoculation to the degradation rate show diesel oil concentration(0.1%~1.0%)and inoculation (0.05~3.0%, bacteria density 1.28×108/ml) have little influence on degradation capability of the consortium and this result indicate the consortium have better...