# High-Performance Microbial Fuel Cell for Aromatic Hydrocarbon Bioremediation: Leveraging a Unique Mangrove-Derived Electrogenic Consortium

## TL;DR

A new microbial community from mangrove sediments improves both energy generation and benzene cleanup in microbial fuel cells.

## Contribution

A novel mangrove-derived electrogenic microbial consortium is introduced for enhanced aromatic hydrocarbon bioremediation and bioelectricity generation.

## Key findings

- The microbial consortium achieved 98.7% benzene removal in 96 hours.
- Voltage increased from 568 mV to 902 mV when switching from acetate to benzene.
- Power density reached 390.1 mW/m², surpassing previous benchmarks.

## Abstract

Enhancing bioelectrocatalytic activity to increase the
efficiency
of toxic compound biodegradation and energy generation continues to
be a critical challenge in bioelectrochemical systems. In this context,
the present study aimed to obtain a novel electrogenic microbial consortium,
sourced from mangrove sediments, capable of improving microbial fuel
cell (MFC) performance in both energy generation and aromatic compound’s
biodegradation. This new microbial consortium was tested in dual-chamber
MFCs designed for the biodegradation of benzene, employed as a model
aromatic compound. Overall, the results demonstrated that the enrichment
of a microbial community derived from mangrove sediments in the southeastern
region of Brazil (State of Espírito Santo) significantly enhanced
bioelectricity generation in MFCs via benzene biodegradation. During
the initial acclimation phase using 1000.0 mg L–1 sodium acetate, the bacterial genera Arcobacter (20.2%) and Comamonas (11.0%) were
predominant. As sodium acetate was progressively replaced and the
MFC operated solely with benzene (330.0 mg L–1), Bacillus (32.9%) and Arcobacter (30.3%) became the dominant genera. The MFC exhibited remarkable
efficiency, achieving 98.7 ± 2.4% benzene removal within 96 h,
while the output voltage increased from 568.0 ± 10.3 mV to 902.3
± 20.6 mV as the feedstock shifted from sodium acetate to benzene.
The maximum power density, Coulombic efficiency, and MFC cumulative
energy efficiency were 390.1 ± 26 mW m–2, 14.4%,
and 17.8%, respectively, surpassing previously established benchmarks
and improving power density by approximately 100-fold compared to
other devices. In conclusion, this innovative electrogenic microbial
consortium, characterized by its unique bacterial diversity, markedly
enhanced electron transfer, voltage, power density, and current generation
in MFCs. It represents a highly promising and sophisticated approach
for both substantial bioelectricity production and the effective bioremediation
of aromatics, especially benzene, a compound known for its extreme
toxicity, mutagenicity, and carcinogenicity.