Isolation And Identification Of Polybrominated Diphenyl Ethers(BDE-47) Degrading Bacterium And Characteristics Of Biodegradation

Polybrominated diphenyl ethers (PBDEs) belong to persistent organic pollutantsbecause of their chemical stability, very low water solubility and bioavailability.2,2’,4,4’-Tetrabromodiphenyl ether (BDE-47) is one of the most predominant PBDEcongeners in environmental media, especially in soil environment, its content was onlysecond to BDE-209. As an important part of Penta-Brominated Diphenyl Ethersindustrial products, due to BDE-47toxicity is higher, harmful to human health, and itwas the secondary metabolites of many high Polybrominated diphenyl ethers, so attractsmore and more attention of researchers. In all kinds of BDE-47degradated methods,microbial degradation due to high efficiency, will not cause two pollution and lowprices, and been highly valued and widely used.We used polymerase chain reaction-denaturing gradient gelelectrophoresis(PCR-DGGE) to examine bacterial diversity of a nearby electronic waste recyclingplant soil in Zhe Jiang City, China. A total of13bands could be detected in the DGGEprofiles. The4dominant bands were sequenced belonged to Aeromonas sp., Bacillus sp.and Acinetobacter sp. respectively, the similarity of up to100%.Application of different acclimated and screen method can isolated14strainswhich used BDE-47as the sole carbon source for growth. By morphologicalidentification, No.1strain was Long bacteria, the others are bacillus brevis. No.3,4-1,5,8,9,12,13strains have flagella, the rest no flagella. Through the Berger’s Manual ofdeterminative bacteriology, the physiological and biochemical identification andmolecular biology identification results showed that: No.14strain belong toAcinetobacter sp, No.10strain belong to Lysinibacillus sp, Residual strains belong tothe genus Bacillus sp. Degradation ability for a period of8days were determinated, theresults showed that the strain No.1,2,4-1and6, had the best ability to degradated ofBDE-47, the degradation rate can almost reach50%.The optimum growth conditions of the strains were determined by experiment. InLB liquid medium, the strains into the logarithmic phase about10hours. The strains No.1and No.2in pH value was6with better growth condition. But for strain No.4-1andNo.6in alkaline environment condition, pH was9better grow. Dissolved oxygen has a certain influence on the growth of different strains, showed that the strains belongs tothe aerobic degradation strains.