[01] Oluwaseun Adelaja, Department of Life Sciences, Applied Biotechnology Research Group, University of Westminster, London, UK; Department of Chemistry, Federal University of Technology, Akure, Nigeria. [02] Tajalli Keshavarz, Department of Life Sciences, Applied Biotechnology Research Group, University of Westminster, London, UK. [03] Lukman Bello, Department of Chemistry, Federal University of Technology, Akure, Nigeria. [04] Godfrey Kyazze, Department of Life Sciences, Applied Biotechnology Research Group, University of Westminster, London, UK.

Petroleum hydrocarbon contamination in the environment resulting from anthropogenic activities has posed a significant health threat. Microbial fuel cell (MFC) could be used as one of the biotechnological tools in hydrocarbons removal especially in the subsurface environment. In this present work, the biodegradation of benzene using a range of inocula (Shewanella oneidensis MR1 14063, Pseudomonas aeruginosa NCTC 10662, mixed cultures and combinations thereof) in MFCs was investigated with respect to degradation rate, degradation efficiency and power production. Results indicated that all inocula tested could degrade benzene effectively. The best performing inocula, AMC (adapted anaerobic digested sludge) gave a benzene degradation rate of 64µM/h (which is 2 fold higher than the anaerobic (non-MFC) control), a maximum power density of 0.82mW/m ² and a COD removal of 87.3%. Ecotoxcity testing based on Vibrio fischeri indicated that the treated solution was three times less toxic than the original solution. This work highlights the possibility of using microbial fuel cells to achieve efficient benzene biodegradation through co-metabolism with concomitant bioelectricity production. MFCs could be employed for treatment of benzene-contaminated subsurface environments or oil refinery wastewater.

Benzene, Biodegradation, Microbial Fuel Cells, Bioelectricity Production, Cometabolism, Inocula

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