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Updated: May 13, 2026
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Electrochemical Detection of Deuterium Kinetic Isotope Effect on Extracellular Electron Transport in Shewanella oneidensis MR-1
Published on: April 16, 2018
Long-term anaerobic conversion of lindane by electrochemically generated hydrogen
Guanxiong Wang1, David Fernández-Verdejo1, Ernest Marco-Urrea1
1BioremUAB, Department of Chemical, Biological and Environmental Engineering, School of Engineering, Universitat Autònoma de Barcelona, Bellaterra, Barcelona 08193, Spain.
Journal of Hazardous Materials
|May 11, 2026
Summary
Microbial electrochemical technology (MET) effectively degrades the persistent pollutant lindane (γ‑HCH) by supplying hydrogen. Flushing with nitrogen gas overcame product inhibition, significantly boosting lindane removal rates.
Area of Science:
- Environmental microbiology
- Biotechnology
- Environmental remediation
Background:
- Lindane (γ‑HCH) is a persistent organic pollutant found in aquifers.
- Electron donor scarcity hinders reductive dechlorination of lindane in situ.
- Microbial electrochemical technology (MET) offers a potential solution for in-situ contaminant degradation.
Purpose of the Study:
- To investigate the long-term efficacy of MET for lindane biotransformation.
- To optimize cathode potential for enhanced lindane degradation.
- To identify microbial communities involved in lindane reduction.
Main Methods:
- A 116-day microbial electrochemical technology (MET) experiment was conducted.
- Cathode potential was sequentially decreased (-0.6 to -0.8 V vs SHE) to supply hydrogen.
- Nitrogen gas flushing was applied to mitigate product inhibition.
- 16S rRNA gene sequencing was used for microbial community analysis.
Main Results:
- Decreasing cathode potential increased hydrogen production and lindane degradation rates.
- Product inhibition by monochlorobenzene and benzene was observed.
- Nitrogen flushing restored microbial activity and significantly boosted lindane removal rates (33.3 to 85.3 µM/d).
- Cathode potential influenced the distribution of degradation products.
Conclusions:
- MET effectively sustains lindane biotransformation by providing a continuous electron source.
- MET can be optimized through cathode potential manipulation and periodic flushing to overcome inhibition.
- The study identified Shewanella and Pseudomonas as key genera potentially involved in lindane reduction.
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