Comparative analysis of microbial community between different cathode systems of microbial fuel cells for denitrification
Chao Li
Ming Xu
Yi Lu
Fang Fang
Jiashun Cao
10.6084/m9.figshare.1569181
https://tandf.figshare.com/articles/journal_contribution/Comparative_analysis_of_microbial_community_between_different_cathode_systems_of_microbial_fuel_cells_for_denitrification/1569181
<p>Two types of cathodic biofilm in microbial fuel cells (MFC) were established for comparison on their performance and microbial communities. Complete autotrophic simultaneous nitrification and denitrification (SND) without organics addition was achieved in nitrifying-MFC (N-MFC) with a total nitrogen (TN) removal rate of 0.35 mg/(L·h), which was even higher than that in denitrifying-MFC (D-MFC) at same TN level. Integrated denaturing gradient gel electrophoresis analysis based on both 16S rRNA and <i>nirK</i> genes showed that <i>Alpha-, Gammaproteobacteria</i> were the main denitrifier communities. Some potential autotrophic denitrifying bacteria which can use electrons and reducing power from cathodes, such as <i>Shewanella oneidensis, Shewanella loihica, Pseudomonas aeruginosa, Starkeya novella</i> and <i>Rhodopseudomonas palustris</i> were identified and selectively enriched on cathode biofilms. Further, relative abundance of denitrifying bacteria characterized by <i>nirK</i>/16S ratios was much higher in biofilm than suspended sludge according to real-time polymerase chain reaction. The highest enrichment efficiency for denitrifiers was obtained in N-MFC cathode biofilms, which confirmed autotrophic denitrifying bacteria enrichment is the key factor for a D-MFC system.</p>
2015-10-08 14:55:09
Microbial fuel cell
denitrification
simultaneous nitrification and denitrification
microbial community
autotrophic denitrifying bacteria