Characteristics and composition of the microbial consortium for decabromodiphenyl ether (BDE-209) degradation

Abstract:

[Objective] A microbial consortium Cf3, which was obtained and enriched from an e-waste contaminated river sediment, was applied to study the characteristics for decabromodiphenyl ether (BDE-209) degradation in order to pave a way for the bioremediation of PBDEs contaminant in sediment. And the composition of the microbial consortium was also studied. [Methods] Congeners of BDE-209 after the biodegradation were analyzed by GC-MS and the degradation rates were calculated. the composition of the microbial consortium was analyzed by DGGE. [Results] High BDE-209 degradation rates were obtained by consortium Cf3. After 120 days incubation, 80.03% BDE-209 was transformed by consortium Cf3 when the initial amount of BDE-209 was 2.6 μmol. Meanwhile, the biomass was obtained and the OD600 value increased from 0.01 to 0.21. The pH also changed from 6.93 to 8.50 during the degradation process. Ten cultivable strains were isolated from this consortium, six of which associated with Citrobacter spp. and four with Alcaligenes spp. based on the 16S rRNA gene sequences. Denaturing gradient gel electrophoresis (DGGE) results showed that other four major genera Wolinella spp., Acidaminococcus spp., Acetobacterium spp. and Desulfovibrio spp. were presented besides Citrobacter spp. and Alcaligenes spp.. However, the bands for Acetobacterium spp. and Desulfovibrio spp. disappeared with prolonging the incubation time. [Conclusion] A microbial consortium with high PBDEs degradation rate was obtained. The data obtained in the study about the characteristics of the degradation of BDE-209 by the microbial consortium and the composition of the consortium could provides some useful information and precious strains resources for the anaerobic bioremediation of polybrominated diphenyl ethers (PBDEs) in the persistent organic polluted environment.

Key words:Degradation consortium, Decabromodiphenyl ether (BDE-209), biodegradation, microbial composition