Microbial communities change in an anaerobic digestion after application of microbial electrolysis cells.
Microbial electrolysis cells (MECs) are being studied to improve the efficiency of anaerobic digesters and biogas production. In the present study, we investigated the effects of electrochemical reactions in AD-MEC (anaerobic digester combined with MECs) on changes in the microbial communities of bulk sludge through 454-pyrosequencing analysis, as well as the effect of these changes on anaerobic digestion. Methanobacterium beijingense and Methanobacterium petrolearium were the dominant archaeal species in AD, while Methanosarcina thermophila and Methanobacterium formicicum were dominant in AD-MEC at steady-state. There were no substantial differences in dominant bacterial species. Clostridia class was more abundant than Bacteroidia class in both reactors. Compared to AD, AD-MEC showed a 40% increase in overall bacterial population, increasing the removal of organic matters and the conversion of volatile fatty acids (VFAs). Thus, the MEC reaction more effectively converts organic matters to VFAs and activates microbial communities favorable for methane production.
Dept. of Environmental Engineering, Chungbuk National University, Cheongju, Republic of Korea. Electronic address: leeb@cbnu.ac.kr.
Beom
B
Lee
Dept. of Environmental Engineering, Chungbuk National University, Cheongju, Republic of Korea. Electronic address: ppp19@cbnu.ac.kr.
Jun-Gyu
JG
Park
Dept. of Environmental Engineering, Chungbuk National University, Cheongju, Republic of Korea. Electronic address: shinkb1634@cbnu.ac.kr.
Won-Beom
WB
Shin
Jeonbong Co. Ltd. Cheongju, Republic of Korea. Electronic address: dongjie1203@cbnu.ac.kr.
Dong-Jie
DJ
Tian
Dept. of Environmental Engineering, Chungbuk National University, Cheongju, Republic of Korea. Electronic address: jhbcbe@cbnu.ac.kr.
Hang-Bae
HB
Jun
D000693:Anaerobiosis; D019149:Bioreactors / Q000382:microbiology*; D004572:Electrolysis; D008697:Methane / Q000096:biosynthesis*; D012722:Sewage / Q000382:microbiology
D012722:Sewage; D008697:Methane
Anaerobic digestion; Archaea; Bacteria; Microbial communities; Microbial electrolysis cell