Open AccessBiogas production using anaerobic groundwater containing a subterranean microbial community associated with the accretionary prism
Author(s) -
Baito Kyohei,
Imai Satomi,
Matsushita Makoto,
Otani Miku,
Sato Yu,
Kimura Hiroyuki
Publication year - 2015
Publication title -
microbial biotechnology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.287
H-Index - 74
ISSN - 1751-7915
DOI - 10.1111/1751-7915.12179
Subject(s) - bioreactor , methanogen , methanogenesis , microbial population biology , groundwater , environmental chemistry , methane , biology , chemistry , bacteria , ecology , botany , geology , genetics , geotechnical engineering
Summary In a deep aquifer associated with an accretionary prism, significant methane ( CH 4 ) is produced by a subterranean microbial community. Here, we developed bioreactors for producing CH 4 and hydrogen ( H 2 ) using anaerobic groundwater collected from the deep aquifer. To generate CH 4 , the anaerobic groundwater amended with organic substrates was incubated in the bioreactor. At first, H 2 was detected and accumulated in the gas phase of the bioreactor. After the H 2 decreased, rapid CH 4 production was observed. Phylogenetic analysis targeting 16 S rRNA genes revealed that the H 2 ‐producing fermentative bacterium and hydrogenotrophic methanogen were predominant in the reactor. The results suggested that syntrophic biodegradation of organic substrates by the H 2 ‐producing fermentative bacterium and the hydrogenotrophic methanogen contributed to the CH 4 production. For H 2 production, the anaerobic groundwater, amended with organic substrates and an inhibitor of methanogens (2‐bromoethanesulfonate), was incubated in a bioreactor. After incubation for 24 h, H 2 was detected from the gas phase of the bioreactor and accumulated. Bacterial 16 S rRNA gene analysis suggested the dominance of the H 2 ‐producing fermentative bacterium in the reactor. Our study demonstrated a simple and rapid CH 4 and H 2 production utilizing anaerobic groundwater containing an active subterranean microbial community.