Enrichment of electrochemically active bacteria using a three-electrode electrochemical cell.
Electrochemically active bacteria were successfully enriched in an electrochemical cell using a positively poised working electrode. The positively poised working electrode (+0.7 V vs. Ag/AgCl) was used as an electron acceptor for enrichment and growth of electrochemically active bacteria. When activated sludge and synthetic wastewater were fed to the electrochemical cell, a gradual increase in amperometric current was observed. After a period of time in which the amperometric current was stabilized (generally 8 days), linear correlations between the amperometric signals from the electrochemical cell and added BOD (biochemical oxygen demand) concentrations were established. Cyclic voltammetry of the enriched electrode also showed prominent electrochemical activity. When the enriched electrodes were examined with electron microscopy and confocal scanning laser microscopy, a biofilm on the enriched electrode surface and bacterium-like particles were observed. These experimental results indicate that the electrochemical system in this study is a useful tool for the enrichment of an electrochemically active bacterial consortium and could be used as a novel microbial biosensor.
Yoon
Seok-Min
SM
Department of Microbial Engineering, University of Konkuk, Seoul 143-701, Korea.
Choi
Chang-Ho
CH
Kim
Mia
M
Hyun
Moon-Sik
MS
Shin
Sung-Hye
SH
Yi
Dong-Heui
DH
Kim
Hyung Joo
HJ
D001419:Bacteria / Q000302:isolation & purification* / Q000378:metabolism* / Q000648:ultrastructure; D001431:Bacteriological Techniques / Q000295:instrumentation; D004563:Electrochemistry / Q000295:instrumentation* / Q000379:methods; D004566:Electrodes; D008855:Microscopy, Electron, Scanning; D010100:Oxygen / Q000378:metabolism; D012722:Sewage / Q000382:microbiology; D014865:Waste Disposal, Fluid; D014871:Water Microbiology
D012722:Sewage; D010100:Oxygen