Response of microbial community structure to pre-acclimation strategies in microbial fuel cells for domestic wastewater treatment
Younghyun Park, Hyunwoo Cho, Jaechul Yu, Booki Min, Hong Suck Kim, Byung Goon Kim, Taeho Lee
Department of Civil and Environmental Engineering, Pusan National University, Busan 609-735, Republic of Korea.
Microbial community structures and performance of air-cathode microbial fuel cells (MFCs) inoculated with activated sludge from domestic wastewater were investigated to evaluate the effects of three substrate pre-acclimation strategies: 1, serial pre-acclimation with acetate and glucose before supplying domestic wastewater; 2, one step pre-acclimation with acetate before supplying domestic wastewater; and 3, direct supply of domestic wastewater without any pre-acclimation. Strategy 1 showed much higher current generation (1.4 mA) and Coulombic efficiency (33.5%) than strategies 2 (0.7 mA and 9.4%) and 3 (0.9 mA and 10.3%). Pyrosequencing showed that microbial communities were significantly affected by pre-acclimation strategy. Although Proteobacteria was the dominant phylum with all strategies, Actinobacteria was abundant when MFCs were pre-acclimated with glucose after acetate. Not only anode-respiring bacteria (ARB) in the genus Geobacter but also non-ARB belonging to the family Anaerolinaceae seemed to play important roles in air-cathode MFCs to produce electricity from domestic wastewater.
Keywords: Air-cathode microbial fuel cell; Anode-respiring bacteria; Domestic wastewater; Microbial community structure; Pyrosequencing.