Performance of a sulfidogenic bioreactor and bacterial community shifts under different alkalinity levels.
The performance of a sulfidogenic bioreactor and the response of bacterial populations to influent alkalinity changes were investigated. The bioreactor reached 40% of sulfate removal efficiency (SRE) with 0 mg l(-1) of alkalinity, and single-stranded conformation polymorphism profiles showed that some members of Bacteroides, Dysgonomonas, Sporobacter, Quinella, and Citrobacter became dominant populations. 16S rRNA gene library analysis indicated that the Actinobacteria group increased from 0% in seed to 23% in sludge. An increase in alkalinity to 1300 mg l(-1) led to a rapid increase of SRE to 65% and changes in the bacterial community. Sequences representing Dysgonomonas, Raoultella, Kluyvera, and Phascolarctobacterium were now found. When alkalinity was deceased to 0 mg l(-1), SRE dropped and the bands representing Raoultella, Kluyvera, and Phascolarctobacterium disappeared, while bands representing Clostridium appeared. A second cycle of low/high alkalinity did not result in obvious changes to the bacterial community. These results indicate that the sulfidogenic bioreactor favored higher influent alkalinity and that the different functional microbial populations responded well to the alkalinity changes.
Zhao
Yang-Guo
YG
College of Environmental Science and Engineering, Ocean University of China, Qingdao 266100, China. yg.zhao@yahoo.com.cn
Li
Xin-Wei
XW
Wang
Jun-Cai
JC
Bai
Jie
J
Tian
Wei-Jun
WJ
D000468:Alkalies / Q000494:pharmacology*; D001419:Bacteria / Q000187:drug effects* / Q000235:genetics / Q000254:growth & development*; D001483:Base Sequence; D019149:Bioreactors / Q000382:microbiology* / Q000592:standards*; D015723:Gene Library; D008969:Molecular Sequence Data; D010084:Oxidation-Reduction / Q000187:drug effects; D010802:Phylogeny; D018807:Polymorphism, Single-Stranded Conformational; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D013431:Sulfates / Q000378:metabolism; D013440:Sulfides / Q000378:metabolism*
D000468:Alkalies; D012336:RNA, Ribosomal, 16S; D013431:Sulfates; D013440:Sulfides