TY - JOUR
T1 - Methanogenesis stimulation and inhibition for the production of different target electrobiofuels in microbial electrolysis cells through an on-demand control strategy using the coenzyme M and 2-bromoethanesulfonate
AU - Park, Sung Gwan
AU - Rhee, Chaeyoung
AU - Shin, Seung Gu
AU - Shin, J.
AU - Mohamed, Hend Omar
AU - Choi, Yun Jeong
AU - Chae, Kyu Jung
N1 - Funding Information:
This work was supported by the National Research Foundation of Korea (NRF) grant funded by the Korea government (MSIT) (No. 2019R1A2C1006356 ).
Publisher Copyright:
© 2019 The Authors
PY - 2019/10
Y1 - 2019/10
N2 - Electron allocation through the suppression or the stimulation of methanogenesis is critical for microbial electrolysis cells (MECs) to produce the desired target product (e.g., CH4 or H2). In this study, selective methanogenesis control using the coenzyme M (CoM) and 2-bromoethanesulfonate (2-BES) was investigated in a two-chambered MEC to evaluate the effect of CoM and 2-BES on the production of different electrobiofuels, net energy conversion efficiency and microbial community structure. Because the CoM is a crucial methyl-group carrier in the final process of methanogenesis, it was postulated that CoM would stimulate methanogenic activity at the anode, while a structural analog of the CoM (i.e., 2-BES) was expected to improve cathodic H2 yield using electrons conserved because of methanogen inhibition (electron equivalence: 8 mol e− = 1 mol CH4 = 4 mol H2). CoM injection in MECs significantly enhanced their CH4 production rate, purity, and yield by 4.5-fold, 14.5%, and 76.1%, respectively, compared to the control. Moreover, microbial community analysis indicated that Methanosaeta, the major acetoclastic methanogen, continued to dominate the microbial community but steadily decreased in relative abundance after the CoM injection. On the other hand, drastic increases in hydrogenotrophic methanogens, such as Methanoculleus and Methanolinea, were observed along with potential syntrophic acetate-oxidizing bacteria. In contrast, CH4 production in the 2-BES injected trials was significantly inhibited by 79.5%, resulting in a corresponding increase of H2 production by 145.5% compared to the control. Unlike the CoM, the microbial community did not noticeably change when 2-BES was injected, although the population size gradually decreased over time. Also, a single injection of CoM and 2-BES, even at low concentrations (500 μM), enabled the desired allocation of electrons as characterized by a high sensitivity, fast response, and negligible interference. In terms of energy conversion efficiency, methanogenesis stimulation approach resulted in higher net energy production than inhibition approach, whereas the remained electrons were not fully converted to hydrogen in case of the inhibition trial, thus producing less energy.
AB - Electron allocation through the suppression or the stimulation of methanogenesis is critical for microbial electrolysis cells (MECs) to produce the desired target product (e.g., CH4 or H2). In this study, selective methanogenesis control using the coenzyme M (CoM) and 2-bromoethanesulfonate (2-BES) was investigated in a two-chambered MEC to evaluate the effect of CoM and 2-BES on the production of different electrobiofuels, net energy conversion efficiency and microbial community structure. Because the CoM is a crucial methyl-group carrier in the final process of methanogenesis, it was postulated that CoM would stimulate methanogenic activity at the anode, while a structural analog of the CoM (i.e., 2-BES) was expected to improve cathodic H2 yield using electrons conserved because of methanogen inhibition (electron equivalence: 8 mol e− = 1 mol CH4 = 4 mol H2). CoM injection in MECs significantly enhanced their CH4 production rate, purity, and yield by 4.5-fold, 14.5%, and 76.1%, respectively, compared to the control. Moreover, microbial community analysis indicated that Methanosaeta, the major acetoclastic methanogen, continued to dominate the microbial community but steadily decreased in relative abundance after the CoM injection. On the other hand, drastic increases in hydrogenotrophic methanogens, such as Methanoculleus and Methanolinea, were observed along with potential syntrophic acetate-oxidizing bacteria. In contrast, CH4 production in the 2-BES injected trials was significantly inhibited by 79.5%, resulting in a corresponding increase of H2 production by 145.5% compared to the control. Unlike the CoM, the microbial community did not noticeably change when 2-BES was injected, although the population size gradually decreased over time. Also, a single injection of CoM and 2-BES, even at low concentrations (500 μM), enabled the desired allocation of electrons as characterized by a high sensitivity, fast response, and negligible interference. In terms of energy conversion efficiency, methanogenesis stimulation approach resulted in higher net energy production than inhibition approach, whereas the remained electrons were not fully converted to hydrogen in case of the inhibition trial, thus producing less energy.
KW - 2-bromoethanesulfonate
KW - Coenzyme M
KW - Electrobiofuel
KW - Energy efficiency
KW - Methanogenesis control
KW - Microbial electrolysis cell
UR - http://www.scopus.com/inward/record.url?scp=85069544735&partnerID=8YFLogxK
U2 - 10.1016/j.envint.2019.105006
DO - 10.1016/j.envint.2019.105006
M3 - Article
C2 - 31330362
AN - SCOPUS:85069544735
SN - 0160-4120
VL - 131
JO - Environment international
JF - Environment international
M1 - 105006
ER -