Assessing microbial exoelectrogenicity for enhanced industrial waste water management and power generation

Abstract

The quest for eco-friendly waste management and renewable sources of energy is rapidly increasing. Microbial fuel cell is promising form of renewable energy, which treat and convert organic matter in wastewater to electricity through the aid of microorganisms present in the wastewater. This study assessed for electrogenic microorganisms that generate power during wastewater treatment at a referenced pH of 8.5 and temperature of 37 0C. The exoelectrogenicity and identity of the microbial isolates were confirmed using microbial fuel cell (MFC) and molecular characterization, respectively. Two bacterial isolates: N4- Providencia species, N6- Proteus species, and three fungal isolates: S9- Clavispora lusitaniae, S10- Candida parapsilosis ,S14- Clavispora lusitaniae with accession numbers; KX548357.1, KX548358.1 and KX548359.1, KX548360.1, KX548361.1, respectively showed exoelectrogenic properties. Proteus species and Candida parapsilosis generated relative high-power densities of 1.59 and 1.55 W/m2, respectively. Significant difference (p < 0.05) in wastewater treatment was also observed. When compared with the control wastewater, S10 recorded about 38% of contaminant removal with the following parameters; biochemical oxygen demand (536.38mg/l), chemical oxygen demand (1974mg/l), total dissolved solid (640mg/l) and conductivity (512µS/cm). The findings showed that, not only bacteria, but fungi are good exoelectrogenic microorganisms for industrial wastewater treatment and power generation in MFC setup.