Screening of Exoelectrogenic Bacteria from Marine Water Inoculated Microbial Fuel Cell for Electricity Generation

Abstract

Microbial fuel cells (MFCs) are bioelectric devices that use bacterial metabolic activity to convert chemical energy to electricity, which offers a potential way to green energy production. Exoelectrogenic bacteria that can transfer their metabolic electrons outside their cells are the primary contributing organisms in this process. This study aims to screen and identify exoelectrogenic bacteria for electricity generation in MFCs. Seawater samples were collected from Kuakata, Bangladesh, and a dual-chambered MFC was used to detect the presence of exoelectrogenic bacteria in the sample. The exoelectrogenic bacterium was screened and isolated from the anode biofilm of the MFC using an MnO₂-supplemented agar medium. The ability of electricity generation by the isolated bacteria was also determined in a dual-chambered MFC. Then, the isolated exoelectrogen was identified via biochemical assay and 16S rRNA gene sequencing. The isolated exoelectrogenic bacteria generated a voltage of up to 0.341 volts, a current density of 0.044 mA/cm², and a maximum power density of 0.015 mW/cm² in the MFC. Biochemical assay and sequencing analysis reported the bacteria as Pseudomonas aeruginosa (similarity index: 99.45%), which demonstrates potential for bioelectricity and sustainable energy production, contributing to novel, eco-friendly resources for biofuel production in Bangladesh.