Isolation and Characterisation of Electrogenic Bacteria from Mud Samples

Abstract

To develop efficient microbial fuel cell systems for green energy production using different waste products, establishing characterised bacterial consortia is necessary. In this study, bacteria with electrogenic potentials were isolated from mud samples and examined to determine biofilm-formation capacities and macromolecule degradation. Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry identifications have revealed that isolates represented 18 known and 4 unknown genuses. They all had the capacities to reduce the Reactive Black 5 stain in the agar medium, and 48 of them were positive in the wolfram nanorod reduction assay. The isolates formed biofilm to different extents on the surfaces of both adhesive and non-adhesive 96-well polystyrene plates and glass. Scanning electron microscopy images revealed the different adhesion potentials of isolates to the surface of carbon tissue fibres. Eight of them (15%) were able to form massive amounts of biofilm in three days at 23 °C. A total of 70% of the isolates produced proteases, while lipase and amylase production was lower, at 38% and 27% respectively. All of the macromolecule-degrading enzymes were produced by 11 isolates, and two isolates of them had the capacity to form a strong biofilm on the carbon tissue one of the most used anodic materials in MFC systems. This study discusses the potential of the isolates for future MFC development applications.

The Performance of a Modified Anode Using a Combination of Kaolin and Graphite Nanoparticles in Microbial Fuel Cells

“…SEM images revealed the different adhesion potentials of isolates to the surface of carbon tissue fibers. Eight of the isolates (15%) were able to form massive amounts of biofilm in three days at 23 °C [ 41 ]. Engel et al studied the biofilm characteristics of pure cultures of Geobacter sulfurreducens and Shewanella oneidensis and compared them to a defined mixed culture of both organisms in bio-electrochemical systems.…”

Effect of pH, COD, and HRT on the Performance of Microbial Fuel Cell Using Synthetic Dairy Wastewater

“…In order to ensure that the S. baltica acclimatized, 10 mL from the 100 mL inoculated media was taken out and added into the anode chamber for 5-7 days. This led to the formation of a biofilm on the surface of the anode [69]. A batch study was carried out simultaneously at different substrate concentrations by using a Monod model to determine the maximum specific growth rate and substrate saturation constant.…”