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The dynamics of electrochemicals and microbial populations during anaerobic treatment of human urine in soil microbial fuel cells (MFCs) were investigated. The experimental MFC was supplemented with daily urine input while the control MFC was without urine. During the treatment process, electrochemical and microbiological parameters in effluent of the urine-supplemented MFC were monitored using standard methods. The pH of the urine increased from 5.70 to 7.16 after 15 days of treatment in the urine supplemented MFC. The concentration of phosphorus, potassium, sodium, calcium, magnesium, total nitrogen and total organic carbon of the urine reduced from 0.76 g/l to 0.07 g/l, 1.91 g/l to 0.17 g/l, 2.24 g/l to 0.09 g/l, 0.14 g/l to 0.003 g/l, 0.08 g/l to 0.00 g/l, 8.25 g/l to 0.74 g/l and 7.10 g/l to 0.53 g/l respectively after 15 days of treatment. Furthermore, Open voltage of the urine supplemented MFC ranged from 5.63 V to 10.34 V while Open voltage of the control ranged from 1.84 V to 5.02 V after 15 days of operation. The population of facultative bacteria (FAB) and strict anaerobic bacteria (SAB) ranged from 64.2 x 104 CFU to 36.2 x 104 CFU and 21.2 x104 CFU to 61.3 x104 CFU respectively with time. The urine supplemented MFC performed significantly (p < 0.05) better than the control with respect to voltage output while significantly reduced concentrations of organic carbon, nitrogen and metallic (salt) species were found. Therefore, the soil MFC may be applied as a waste management option to treat human urine while generating electricity before disposal.
Logan BE, Aelterman P, Hamelers B, Rozendal R, Schroder U, Keller J, Freguiac S, Verstraete W, Rabaey K. Microbial fuel cells: Methodology and technology. Environmental Science and Technology. 2006;40(17):5181–5192.
Rabaey K, Boon N, Siciliano SD, Verhaege M, Verstraete W. Biofuel cells select for microbial consortia that self-mediate electron transfer. Applied and Environmental Microbiology. 2004; 70(9):5373–5382.
Kim BH, Chang IS, Gadd GM. Challenges in microbial fuel cell development and operation. Applied Microbiology and Biotechnology. 2007;76(3):485–494.
Virdis B, Rabaey K, Yuan Z, Keller J. Microbial fuel cells for simultaneous carbon and nitrogen removal. Water Research. 2008;42(12):3013-3024.
Orellana R, Leavitt JJ, Comolli LR, Csencsits R, Janot N, Flanagan KA, Gray AS, Leang C, Izallalen M, Mester T. U (VI) reduction by a diversity of outer surface c-type cytochromes of Geobacter sulfurreducens. Journal of Applied and Environmental Microbiology. 2013;79: 6369– 6374.
Aelterman P, Rabaey K, Pham TH, Boon N, Verstraete W. Continuous electricity generation at high voltages and currents using stacked microbial fuel cells. Environmental Science and Technology. 2006;40:3388–3394.
Bermek H, Catal T, Akan SS, Ulutas MS, Kumru M, Ozguven M, Liu H, Ozcelik H, Akarsubasi AT. Olive mill wastewater treatment in single-chamber air-cathode microbial fuel cells. World Journal of Microbiology and Biotechnology. 2014;30: 1177–1185.
Kumar R, Singh L, Wahid ZA, Fadhil M. Exoelectrogensis in microbial fuel cells towards bioelectricity generation: A review. International Journal of Energy Research. 2015;39:1048– 1067.
Reguera G, McCarthy KD, Mehta T, Nicoll JS, Tuominen MT, Lovley DR. Extracellular electron transfers via microbial nanowires. Natur. 2005;435:1098–1101.
Pham TH, Rabaey K, Aelterman P, Clauwaert P, De Schamphelaire L, Boon N, Verstraete W. Microbial Fuel Cells in Relation to Conventional Anaerobic Digestion Technology. Engineering Life Science. 2006;6(3):285–292.
Sun M, Reible DD, Lowry GV, Gregory KB. Effect of applied voltage, initial concentration, and natural organic matter on sequential reduction/oxidation of nitrobenzene by graphite electrodes. Environmental Science and Technology. 2012;46:6174–6181.
Zhou M, Wang H, Hassett JD, Gu T. Recent advances in microbial fuel cells (MFCs) and microbial electrolysis cells (MECs) for wastewater treatment, bioenergy and bio-products. Journal of Chemical Technology and Biotechnology. 2013;88:508–518.
Kumar R, Singh L, Wahid ZA. Exoelectrogensis: Recent advances in molecular drivers involved in extracellular electron transfer and strategies used to improve it for microbial fuel cell applications. Renewable and Sustainable Energy Review. 2016;56:1322–1336.
Venkata MS, Velvizhi G, Modestra JA, Srikanth S. Microbial fuel cell: Critical factors regulating bio-catalyzed electrochemical process and recent advancements. Renewable and Sustainable Energy Review. 2014;40:779–797.
Oh S, Kim J, Premier G, Lee T, Changwon K, Sloan W. Sustainable wastewater treatment: How might microbial fuel cells contribute. Journal of Biotechnological Advances. 2010;28:871–881.
Rhoads A, Beyenal H, Lewandowski Z. Microbial fuel cell using anaerobic respiration as an anodic reaction and biomineralized manganese as a cathodic reactant. Environmental Science and Technology. 2005;39:4666–4671.
Simeon MI, Raji OA, Kuti IA. Determination of the suitability of urine as substrate in a power generating soil microbial fuel cell. SEET Annual Conference. 2016;16:114–122.
Yan H, Saito T, Rrgan JM. Nitrogen removal in a single-chamber microbial fuel cell with nitrifying biofilm enriched at the air cathode. Water Research. 2012;46:2215–2224.
APHA. Standard Methods for the Examination of Water and Wastewater (21st Ed.). Washington, DC: American Public Health Association; 2005.
Mahlangu TO, Mpenyana-Monyatsi L, Momba MNB, Mamba BB. A simple cost-effective bio-sand filter (BSFZ) for removal of chemical contaminants from water. Journal of Chemical Engineering and Materials Science. 2011;2(10):156–167.
Ogbonna CB, Stanley HO, Abu GO. Effect of Seasonal Variation on Anaerobic Treatment of Organic Municipal Solid Waste-II: Population Dynamics of Bacteria and Archaea Communities. Applied Microbiology. 2018a;4(3):1–9.
Ogbonna CB, Stanley HO, Abu GO. Effect of Liquid Digestate on Agricultural Soil–II: Microbial Population Dynamics. Applied Microbiology. 2018b;4(1):1–10.
Abdulkadir M, Waliyu S. Screening and isolation of soil bacteria for the ability to produce antibiotics. European Journal of Applied Sciences. 2012;4(5):211–215.
Wolf RS. Techniques for Cultivating Methanogens. Methods in Enzymology. 2011;494:1–22.
Holdman LV, Moore WEC. Roll-Tube Techniques for Anaerobic bacteria. The American Journal of Clinical Nutrition. 1972;25:1314–1317.
Holt JG, Krieg NR. Bergey’s Manual of Determinative Bacteriology (9th Ed). The Williams and Wilkins Co., Baltimore; 1994.
Dubey RC, Maheshwari DK. Practical Microbiology, S. Chand and Company LTD Ram Nagar, New Delhi. 2008;21-231.
Woodland J. Bacteriology: In Heil, N. (Ed) NWFHS Laboratory Procedures Manual (5th Ed), Chapter five. U.S. Fish and Wildlife Service, Warm Spring, GA. 2009;75–122.
Niessen J, SchroE` der U, Scholz F. Exploiting complex carbohydrates for microbial electricity generation-a bacterial fuel cell operating on starch. Journal of Electrochemical Communication. 2004;6:955–958.
Phung NT, Lee J, Kang KH, Chang IS, Gadd GM, Kim BH. Analysis of microbial diversity in oligotrophic microbial fuel cells using 16S rDNA sequences. FEMS Microbiological Letter. 2004; 233:77–82.
Franks AE, Nevin KP. Microbial Fuel Cells, A Current Review. Energies. 2013;3:899-919.
Virdis B, Rabaey K, Rozendal RA, Yuan ZG, Keller J. Simultaneous nitrification, denitrification and carbon removal in microbial fuel cells. Water Research. 2010;44(9):2970–2980.
Xie S, Liang P, Chen Y, Xia X,Huang X. Simultaneous carbon and nitrogen removal using an oxic/anoxic-biocathode microbial fuel cells coupled system. Bioresource Technology. 2011; 102(1):348–354.
Dada EO, Aruwa CE. Microorganisms associated with urine contaminated soils around lecture theatres in Federal University of Technology, Akure, Nigeria. International Journal of Applied Microbiology and Biotechnology Research. 2014;2:79-85.