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With oil exploration and development of oil industry, oil has become the most important human survival and development of energy sources. In oil exploration, storage and use of the process, due to an accident, abnormal operation and maintenance and other reasons, will occur petroleum hydrocarbon spills and emissions. Oil pollution has enormous human and environmental hazards, has been a threat to humans and other organisms to survive and develop. Thus, scholars around the world are very concerned about oil pollution problems, and actively seek safe, economical and reliable method of governance. In recent years, with the development of modern biotechnology, microbiology in environmental protection has become increasingly broad application prospects. Physical, chemical methods, oil pollution bioremediation technology has great advantages, has become a hot research. In this study, the long-term petroleum contaminated soils effectively isolated from a petroleum-degrading bacteria, named Z1a-B, and its identification; then subjected to mutagenesis in order to obtain efficient processing of oil degrading bacteria, and high oil degrading bacteria to degrade conditions and other aspects of research, obtained the following results: 1. Through enrichment, domestication and separation test, get a screening advantage petroleum degrading strains measured by shake flask fermentation its oil degradation rate of 66.4%. (2) using the blood test plate and the oil discharge activity detected, Z1a-B strain can produce biosurfactants, and has a strong activity of hemolysis and drain, indicating the generation of a strong ability of biosurfactant. To further understand the strain Zla-B's ability to degrade oil by gas chromatography - mass spectrometry (GS-MS) method for each component before and after degradation of crude oil were analyzed and found that strains Z1a-B for C12 ~ C38 most of the long- alkanes have good degradation effect, indicating that the strain has a wide spectrum of degradation, degradation of petroleum contaminants can be very good. 3 utilization colony morphology, individual form and scanning electron microscopy spore morphology, physiology and biochemistry and ancillary testing, preliminary identification of strains Z1a-B of the genus Streptomyces white spore taxa. 4 to strain Z1a-B as starting strain, its UV mutagenesis and UV plus LiCl complex mutation, compared to mutagenic effects choose the right way mutagenesis, mutagenesis tablet after pre-screening and rescreening flask results UV plus LiCl complex mutation showed good effect on UV mutagenesis, mutagenesis by UV plus LiCl composite strain Z1a-B for mutagenesis treatment to obtain a significantly improved oil degradation ability of the strains ZB Ⅱ -12. 5. contrast induced colony characteristics change before and after the strain and degradation found changed colony morphology after mutagenesis of strain produced ZB Ⅱ -12 biosurfactant increase capacity and activity, increased degradation, degradation wider spectrum, which can degrade more many types of petroleum hydrocarbons, degradation and more completely. 6. Optimum nitrogen and phosphorus sources and optimization of culture conditions test results show that the optimum strain ZB Ⅱ -12 nitrogen and phosphorus sources were KN03 and K2HPO4; their optimum growth conditions for the initial pH 7.5, temperature 30 ℃, inoculation the amount of 8%, oil concentration 7 g · L-1, and the pH value of 6.0 to 9.0 and the temperature 20 ~ 42 ℃ when the strain ZB Ⅱ -12 oil degradation rate reached more than 60%, indicating that it can tolerate a wide range pH , temperature changes. 7 orthogonal test for petroleum contaminated soil bioremediation indoor studies have shown that various factors affecting the oil degradation rate of the primary and secondary order of inoculation gt; KN03 gt; K2HP04 gt; sawdust, soil remediation optimal combination of oil degradation KNO33 g · L-1, K2HPO40.75 g · L-1, sawdust, 30 g · L-1, inoculum size of 8%. For oil contaminated soil remediation process, add the right amount of fertilizer, nutrients nitrogen and phosphorus source, leavening agents, can effectively improve the efficiency of microbial degradation. By measuring the amount of plant growth, and the rate of oil degradation of pollutants measured results match more directly reflects the effect of microbial treatment of oil pollution. 8 solid state fermentation experiments showed that the ratio of the solid medium to use bran 2 g, chicken 40 g, peat 52.5 g, 1.5 g or quicklime bran 2 g, 大米 20 g, soybean flour 28g, compared with 1.5 g of quicklime Jia. In both the ratio of medium Streptomyces fast growth, growing well, spore quantity. The use of inexpensive and readily available starting materials a lot of spores that can be directly used for bioremediation of petroleum contaminated soil treatment, the production of the bacterial activity is high, easy to store and transport, is conducive to the use of live agents for bioremediation of petroleum contaminated soil treatment large-scale promotion and application.
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