Journal of Energy Bioscience 2024, Vol.15, No.5, 314-325 http://bioscipublisher.com/index.php/jeb 318 5.3 Renewable and waste-derived fuels The use of renewable and waste-derived fuels in EBCs is a promising approach to enhance sustainability and reduce environmental impact. Whole-cell biocatalysis has been explored to convert waste biomass into valuable biofuels, leveraging the robustness of microbial systems to process a wide range of substrates (Madavi et al., 2021). This method not only provides a sustainable source of fuel but also addresses waste management issues by converting waste materials into energy. Additionally, innovative approaches have been developed to utilize pollutants as fuels in EBCs, demonstrating the versatility and environmental benefits of these systems (Li et al., 2020). For example, a novel single-enzymatic biofuel cell has been designed to use persistent pollutants like bisphenol A and hydroquinone as fuel, showcasing the potential for wastewater recycling and pollutant degradation (Li et al., 2020). 6 Case Study: Successful Implementations in Enzyme-Catalyzed Biofuel Cells 6.1 Case study 1: medical devices and glucose biofuel cells Enzyme-catalyzed biofuel cells (EBFCs) have shown significant promise in powering medical devices, particularly those that can utilize glucose as a fuel source. For instance, a study demonstrated the development of a glucose/oxygen biofuel cell with a three-dimensional macroporous gold film-based biocathode and a bacterial surface-displayed glucose dehydrogenase-based bioanode. This configuration achieved a high power output of (55.8±2.0) μW cm-2 and maintained 84% of its maximal power density after 55 hours of continuous operation, highlighting its potential for long-term applications in medical devices (Hou et al., 2014). Another study optimized a membraneless glucose/oxygen enzymatic biofuel cell, achieving a maximum power output of 20 μW cm-2 and an estimated half-life of up to 12 hours, which is crucial for the reliable operation of implantable medical devices (Shao et al., 2013). 6.2 Case study 2: wastewater treatment and environmental applications Enzyme-catalyzed biofuel cells have also been explored for environmental applications, such as wastewater treatment. These biofuel cells can harness the chemical energy from organic waste to generate electricity, thus providing a dual benefit of waste reduction and energy production. A review highlighted the potential of enzymatic biofuel cells in various environmental applications, emphasizing their ability to operate under mild conditions and their biodegradability, which makes them suitable for sustainable wastewater treatment processes (Figure 2) (Barelli et al., 2021). Additionally, the use of bioelectrocatalytic carbon nanotube-based pellets in a flow-through fuel cell design demonstrated the feasibility of integrating multiple biofuel cells to achieve higher power outputs, which can be beneficial for large-scale environmental applications (Abreu et al., 2017). Figure 2 Schematic representation of an enzymatic biofuel cell (EFC) device (Adopted from Barelli et al., 2021)
RkJQdWJsaXNoZXIy MjQ4ODYzMg==