Enhanced bioelectricity generation by improving pyocyanin production and membrane permeability through sophorolipid addition in Pseudomonas aeruginosa-inoculated microbial fuel cells

• Published in: Bioresource technology 2014-09, Vol.167, p.490-494
• Main Authors: Shen, Hai-Bo, Yong, Xiao-Yu, Chen, Yi-Lu, Liao, Zhi-Hong, Si, Rong-Wei, Zhou, Jun, Wang, Shu-Ya, Yong, Yang-Chun, OuYang, Ping-Kai, Zheng, Tao
• Format: Article
• Language: English
• Subjects: Biochemical fuel cells; Bioelectric Energy Sources - microbiology; Bioelectricity; Cell Membrane Permeability; Chromatography, High Pressure Liquid; Current density; Density; Electricity; Electrochemical Techniques; Electrodes; Electrons; Glycolipids - metabolism; Membranes; Microbial fuel cell (MFC); Microorganisms; Permeability; Pseudomonas; Pseudomonas aeruginosa; Pseudomonas aeruginosa - metabolism; Pyocyanin; Pyocyanine - biosynthesis; Sophorolipid; Surface-Active Agents - metabolism
• ISSN: 0960-8524; 1873-2976
• DOI: 10.1016/j.biortech.2014.05.093

•Sophorolipid enhanced the membrane permeability of electrochemically active bacteria.•Sophorolipid decreased the charge transfer resistance of MFC.•The electron shuttle (pyocyanin) concentration increased upon sophorolipid addition.•Addition of bio-surfactant is a powerful strategy to increase the performance of MFC. Improvement on electron shuttle-mediated extracellular electron transfer (EET) is of great potential to enhance the power output of MFCs. In this study, sophorolipid was added to enhance the performance of Pseudomonas aeruginosa-inoculated MFC by improving the electron shuttle-mediated EET. Upon sophorolipid addition, the current density and power density increased ∼1.7 times and ∼2.6 times, respectively. In accordance, significant enhancement on pyocyanin production (the electron shuttle) and membrane permeability were observed. Furthermore, the conditions for sophorolipid addition were optimized to achieve maximum pyocyanin production (14.47±0.23μg/mL), and 4 times higher power output was obtained compared to the control. The results substantiated that enhanced membrane permeability and pyocyanin production by sophorolipid, which promoted the electron shuttle-mediated EET, underlies the improvement of the energy output in the P. aeruginosa-inoculated MFC. It suggested that addition of biosurfactant could be a promising way to enhance the energy generation in MFCs.