Selective enrichment of electrogenic bacteria for fuel cell application: Enumerating microbial dynamics using MiSeq platform

• Published in: Bioresource technology Vol. 213; pp. 146 - 154
• Main Authors: Vamshi Krishna, K., Venkata Mohan, S.
• Format: Journal Article
• Language: English
• Published: England Elsevier Ltd 01.08.2016
• Subjects: Bacteria - chemistry; Bacteria - genetics; Biodiversity; Bioelectric Energy Sources - microbiology; Coulombic efficiency; Electricity; Electrochemistry; Electrodes; Electrogenic bacteria; Fatty Acids, Volatile - analysis; Fermentation; Heat-shock; Hydrogen-Ion Concentration; Iodopropane; Microbial Electrochemical system; RNA, Ribosomal, 16S - genetics; Sequence Analysis, DNA - methods; Coulombic efficiency; Microbial Electrochemical system; Heat-shock; Iodopropane; Electrogenic bacteria
• ISSN: 0960-8524; 1873-2976
• DOI: 10.1016/j.biortech.2016.03.117

•Selective enrichment of electrogens by iodopropane & heat pretreatments.•Both strategies yielded high power output compared to untreated MFC.•High coulombic efficiency was observed in iodopropane pretreated MFC.•MiSeq analysis depicted enrichment of exoelectrogens in pretreated MFCs. This study is intended to examine the effect of pretreatment on selective enrichment of electrogenic bacteria from mixed culture. It has been observed that the iodopropane and heat-shock pretreatments suppress the growth of non-exoelectrons, while selecting only a limited number of strains belonging to genera Xanthomonas, Pseudomonas and Prevotella while untreated control inoculum showed more diverse community comprising of both exoelectrogens and non-exoelectrogens. High power output was observed in iodopropane (180mW/m2) pretreated microbial fuel cell (MFC) compared to heat-shock pretreated MFC (128mW/m2) and untreated control (92mW/m2). Coulombic efficiency of iodopropane and heat-shock pretreated MFC was higher compared to untreated control MFC, while drop in pH and volatile fatty acids (VFA) production was less in iodopropane pretreated MFC signifying the shifts in bacterial community structure toward electrogenesis instead of fermentation. These results signify the role of iodopropane and heat pretreatments on enrichment of electrogenic bacteria for fuel cell application.