TY - JOUR
T1 - Hydrogen consumption in microbial electrochemical systems (MXCs)
T2 - The role of homo-acetogenic bacteria
AU - Parameswaran, Prathap
AU - Torres, Cesar
AU - Lee, Hyung Sool
AU - Rittmann, Bruce
AU - Krajmalnik-Brown, Rosa
N1 - Funding Information:
The research was supported by the Biohydrogen Initiative at Arizona State University and OpenCEL, LLC .
PY - 2011/1
Y1 - 2011/1
N2 - Homo-acetogens in the anode of a microbial electrolysis cell (MEC) fed with H2 as sole electron donor allowed current densities similar to acetate-fed biofilm anodes (∼10A/m2). Evidence for homo-acetogens included accumulation of acetate at high concentrations (up to 18mM) in the anode compartment; detection of formate, a known intermediate during reductive acetogenesis by the acetyl-CoA pathway; and detection of formyl tetrahydrofolate synthetase (FTHFS) genes by quantitative real-time PCR. Current production and acetate accumulation increased in parallel in batch and continuous mode, while both values decreased simultaneously at short hydraulic retention times (1h) in the anode compartment, which limited suspended homo-acetogens. Acetate produced by homo-acetogens accounted for about 88% of the current density of 10A/m2, but the current density was sustained at 4A/m2 at short hydraulic retention time because of a robust partnership of homo-acetogens and anode respiring bacteria (ARB) in the biofilm anode.
AB - Homo-acetogens in the anode of a microbial electrolysis cell (MEC) fed with H2 as sole electron donor allowed current densities similar to acetate-fed biofilm anodes (∼10A/m2). Evidence for homo-acetogens included accumulation of acetate at high concentrations (up to 18mM) in the anode compartment; detection of formate, a known intermediate during reductive acetogenesis by the acetyl-CoA pathway; and detection of formyl tetrahydrofolate synthetase (FTHFS) genes by quantitative real-time PCR. Current production and acetate accumulation increased in parallel in batch and continuous mode, while both values decreased simultaneously at short hydraulic retention times (1h) in the anode compartment, which limited suspended homo-acetogens. Acetate produced by homo-acetogens accounted for about 88% of the current density of 10A/m2, but the current density was sustained at 4A/m2 at short hydraulic retention time because of a robust partnership of homo-acetogens and anode respiring bacteria (ARB) in the biofilm anode.
KW - Biofilm anode
KW - Formyl tetrahydrofolate synthetase (FTHFS)
KW - Homo-acetogens
KW - Hydraulic retention time (HRT)
KW - Microbial fuel cells
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U2 - 10.1016/j.biortech.2010.03.133
DO - 10.1016/j.biortech.2010.03.133
M3 - Article
C2 - 20430615
AN - SCOPUS:77957377821
SN - 0960-8524
VL - 102
SP - 263
EP - 271
JO - Bioresource Technology
JF - Bioresource Technology
IS - 1
ER -