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Isolated and screened from the activated sludge of a coking plant out two to polycyclic aromatic hydrocarbons fluorene as the sole carbon and energy growth of bacteria (respectively named W-1 and W-2), in the morphological observation, physiological and biochemical tests foundation on the 16S rDNA sequence analysis and phylogenetic analysis, to identify strains W-faecalis Alcaligenes of Alcaligenes faecalis, W-2 for the micro-eosinophilic oligonucleotide raising Aeromonas bacteria (Stenotrophomonas acidaminiphila). Strain W-1 and W-2 of the fluorene degradation efficiency, respectively, in the inoculation amount of 10% (V / V), the initial fluorene concentration of 40 mg / L, pH 7.0 and a temperature of 30 ° C conditions, inoculation after 11 d of incubation, reached 87.8% and 86.0%; strains mixed culture under the same conditions, can significantly improve the ability to degrade of the fluorene, fluorene degradation efficiency of 94.0%. Using the alkaline lysis method and the boiling lysis method of strain W-1 and W-2 for plasmid extraction, and were not found in the plasmid bands, speculated strain fluorene degradation genes may be located on the chromosome. Strain W-1 and W-2 PAHs degradation characteristics. Contain 20mg / L [Lv Qu] pyrene, anthracene, and phenanthrene culture system, strain W-1 [Lv flexor, pyrene, anthracene, and phenanthrene degradation efficiency up to 95.5%, 71.0%, 85.7 % and 80.0%, strains W-2 [Lv flexor, pyrene, anthracene, and phenanthrene degradation efficiency of up to 86.0%, 80.2%, 91.4% and 94.5%. The research results show that the two strains can be excellent microbial resources as repair of polycyclic aromatic hydrocarbons in complex environmental pollution. Fluorene concentration in water, cast the amount of bacteria and pH factors such strains degradation fluorene, the stimulating effect of the external carbon source (glucose, phthalic acid, salicylic acid, catechol, and naphthyl) fluorene biological degradation been studied. The results show that the vote in the amount of bacteria, and initial fluorene concentration and pH and other factors impact on the degradation of fluorene strain W-1 fluorene appropriate degradation conditions: fluorene concentration of 10mg / L ~ 40mg / L, voted 7% of the amount of bacteria ~ 25%, pH 7.0 ~ 9.0. Strain W-2 degradation of fluorene optimum conditions: fluorene concentration of 10 mg / L to 40 mg / L, voted bacteria amount 7% to 20% of pH 6.0 to 7.0. External carbon source of strain W-1 and W-2 degradation of fluorene quite different, adding to the reaction system, the amount of glucose, salicylic acid, catechol, and polycyclic aromatic hydrocarbons naphthalene, strain W-2 could stimulate fluorene degradation. When the dosage of 100 mg / L glucose and 50 mg / L, salicylic acid, catechol and naphthalene, strain W-2 water fluorene degradation efficiency of up to 93.8%, 97.3%, 97.4% and 96.5 %. The dosage amount phthalate and naphthalene strain W-1 degradation fluorene has a stimulating effect. Dosage of 50 mg / L phthalic acid and 20 mg / L naphthalene, strain W-1 water fluorene degradation efficiency reached 94.6% and 97.1% to the reaction system.
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