TY - JOUR
T1 - Synergistic Inorganic Carbon and Denitrification Genes Contributed to Nitrite Accumulation in a Hydrogen-Based Membrane Biofilm Reactor
AU - Pang, Si
AU - Rittmann, Bruce E.
AU - Wu, Chengyang
AU - Yang, Lin
AU - Zhou, Jingzhou
AU - Xia, Siqing
N1 - Funding Information:
Funding: This research was funded by National Key Project of Research and Development Plan of China, grant number 2021YFC3201300 and National Natural Science Foundation of China, grant number NSFC 51678422.
Publisher Copyright:
© 2022 by the authors. Licensee MDPI, Basel, Switzerland.
PY - 2022/5
Y1 - 2022/5
N2 - Partial denitrification, the termination of NO3−-N reduction at nitrite (NO2−-N), has received growing interest for treating wastewaters with high ammonium concentrations, because it can be coupled to anammox for total-nitrogen removal. NO2− accumulation in the hydrogen (H2)-based membrane biofilm reactor (MBfR) has rarely been studied, and the mechanisms behind its accumulation have not been defined. This study aimed at achieving the partial denitrification with H2-based autotrophic reducing bacteria in a MBfR. Results showed that by increasing the NO3− loading, increasing the pH, and decreasing the inorganic-carbon concentration, a nitrite transformation rate higher than 68% was achieved. Community analysis indicated that Thauera and Azoarcus became the dominant genera when partial denitrification was occurring. Functional genes abundances proved that partial denitrification to accumulate NO2− was correlated to increases of gene for the form I RuBisCo enzyme (cbbL). This study confirmed the feasibility of autotrophic partial denitrification formed in the MBfR, and revealed the inorganic carbon mechanism in MBfR denitrification.
AB - Partial denitrification, the termination of NO3−-N reduction at nitrite (NO2−-N), has received growing interest for treating wastewaters with high ammonium concentrations, because it can be coupled to anammox for total-nitrogen removal. NO2− accumulation in the hydrogen (H2)-based membrane biofilm reactor (MBfR) has rarely been studied, and the mechanisms behind its accumulation have not been defined. This study aimed at achieving the partial denitrification with H2-based autotrophic reducing bacteria in a MBfR. Results showed that by increasing the NO3− loading, increasing the pH, and decreasing the inorganic-carbon concentration, a nitrite transformation rate higher than 68% was achieved. Community analysis indicated that Thauera and Azoarcus became the dominant genera when partial denitrification was occurring. Functional genes abundances proved that partial denitrification to accumulate NO2− was correlated to increases of gene for the form I RuBisCo enzyme (cbbL). This study confirmed the feasibility of autotrophic partial denitrification formed in the MBfR, and revealed the inorganic carbon mechanism in MBfR denitrification.
KW - autotrophic partial denitrification
KW - denitrification genes
KW - inorganic carbon fixing genes
KW - membrane biofilm reactor
KW - microbial community
KW - nitrite accumulation
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U2 - 10.3390/bioengineering9050222
DO - 10.3390/bioengineering9050222
M3 - Article
AN - SCOPUS:85130908196
SN - 2306-5354
VL - 9
JO - Bioengineering
JF - Bioengineering
IS - 5
M1 - 222
ER -