Complete Genome Sequence of Pseudomonas Stutzeri S116 Provides Insights into the Mechanism of Microbial Fuel Cells

To identify suitable biocatalysts applied in microbial fuel cells (MFCs), Pseudomonas stutzeri S116 isolated from marine sludge was investigated, which possessed excellcent bioelectricity generation ability (BGA). Herein, P. stutzeri as a bioanode and biocathode achieved maximum output voltage (254.2 mV and 226.0 mV), and power density of (765 mW/m2 and 656.6 mW/m2). Complete genome sequencing of P. stutzeri was performed to reveal its potential microbial functions. The results exhibited that the strain was the ecologically dominant Pseudomonas, and its primary annotations were associated with energy production and conversion (6.84%), amino acid transport and metabolism (6.82%) and inorganic ion transport and metabolism (6.77%). The thirty-six genes involved in oxidative phosphorylation indicate that strain possesses an integrated electron transport chain. Moreover, many genes encoding redox mediators (mainly riboflavin and phenazine) were detected in the databases. Simultaneously, thiosulfate oxidization and dissimilatory nitrate reduction were annotated in the sulfur metabolism and nitrogen metabolism pathway. Gene function and cyclic voltammetry (CV) analysis indicated BGA of P. stutzeri probably was attributed to its cytochrome c and redox mediators, which enhance extracellular electron transfer (EET) rate.

From Waste to Watts: Updates on Key Applications of Microbial Fuel Cells in Wastewater Treatment and Energy Production

Due to fossil fuel depletion and the rapid growth of industry, it is critical to develop environmentally friendly and long-term alternative energy technologies. Microbial fuel cells (MFCs) are a powerful platform for extracting energy from various sources and converting it to electricity. As no intermediate steps are required to harness the electricity from the organic substrate’s stored chemical energy, MFC technology offers a sustainable alternative source of energy production. The generation of electricity from the organic substances contained in waste using MFC technology could provide a cost-effective solution to the issue of environmental pollution and energy shortages in the near future. Thus, technical advancements in bioelectricity production from wastewater are becoming commercially viable. Due to practical limitations, and although promising prospects have been reported in recent investigations, MFCs are incapable of upscaling and of high-energy production. In this review paper, intensive research has been conducted on MFCs’ applications in the treatment of wastewater. Several types of waste have been extensively studied, including municipal or domestic waste, industrial waste, brewery wastewater, and urine waste. Furthermore, the applications of MFCs in the removal of nutrients (nitrogen and sulphates) and precious metals from wastewater were also intensively reviewed. As a result, the efficacy of various MFCs in achieving sustainable power generation from wastewater has been critically addressed in this study.