Microbial electricity generation enhances decabromodiphenyl ether (BDE-209) degradation

Area of Science:

• Environmental Science
• Microbiology
• Environmental Engineering

Background:

• Polybrominated diphenyl ethers (PBDEs) are persistent environmental pollutants with significant biotoxicity.
• Developing effective remediation technologies for PBDEs is crucial due to their environmental persistence.
• Microbial fuel cells (MFCs) offer a promising approach for bioremediation of organic pollutants.

Purpose of the Study:

• To investigate whether microbial electricity generation enhances the anaerobic degradation of PBDEs, specifically BDE-209.
• To analyze the microbial community structure and functional genes involved in PBDE degradation under different MFC conditions.
• To correlate microbial community changes with the efficiency of PBDE removal.

Main Methods:

• Utilized closed-circuit (c-MFC) and open-circuit (o-MFC) microbial fuel cell systems for BDE-209 degradation experiments.
• Employed the GeoChip 4.0 functional gene array to analyze microbial community composition and functional genes.
• Quantified PBDE concentrations and degradation products over a 70-day period.

Main Results:

• Distinct microbial community structures were observed between c-MFCs and o-MFCs.
• c-MFCs showed significantly lower concentrations of BDE-209 and its brominated products compared to o-MFCs.
• Higher diversity and abundance of functional genes, including those for reductive dechlorination and aromatic hydrocarbon degradation, were found in c-MFCs, correlating positively with PBDE removal.

Conclusions:

• Microbial electricity generation via electrodes effectively promotes PBDE degradation.
• The enhanced degradation is linked to the stimulation of specific microbial functional genes involved in pollutant metabolism and nutrient cycling.
• MFC technology presents a viable strategy for the bioremediation of PBDE-contaminated environments.