title: Denitrifying capability and community dynamics of glycogen accumulating organisms during sludge granulation in an anaerobic-aerobic sequencing batch reactor.
abstract: Denitrifying capability of glycogen accumulating organisms (GAOs) has received great attention in environmental science and microbial ecology. Combining this ability with granule processes would be an interesting attempt. Here, a laboratory-scale sequencing batch reactor (SBR) was operated to enrich GAOs and enable sludge granulation. The results showed that the GAO granules were cultivated successfully and the granules had denitrifying capability. The batch experiments demonstrated that all NO3(-)-N could be removed or reduced, some amount of NO2(-)-N were accumulated in the reactor, and N2 was the main gaseous product. SEM analysis suggested that the granules were tightly packed with a large amount of tetrad-forming organisms (TFOs); filamentous bacteria served as the supporting structures for the granules. The microbial community structure of GAO granules was differed substantially from the inoculant conventional activated sludge. Most of the bacteria in the seed sludge grouped with members of Proteobacterium. FISH analysis confirmed that GAOs were the predominant members in the granules and were distributed evenly throughout the granular space. In contrast, PAOs were severely inhibited. Overall, cultivation of the GAO granules and utilizing their denitrifying capability can provide us with a new approach of nitrogen removal and saving more energy.
authors.affiliation: Institute of Health and Environmental Medicine, Tianjin Key Laboratory of Risk Assessment and Control for Environment and Food Safety, Tianjin 300050, China.
authors.forename: Zhang
authors.initials: Z
authors.lastname: Bin
authors.affiliation: Institute of Health and Environmental Medicine, Tianjin Key Laboratory of Risk Assessment and Control for Environment and Food Safety, Tianjin 300050, China.
authors.forename: Xue
authors.initials: X
authors.lastname: Bin
authors.affiliation: Institute of Health and Environmental Medicine, Tianjin Key Laboratory of Risk Assessment and Control for Environment and Food Safety, Tianjin 300050, China.
authors.forename: Qiu
authors.initials: Q
authors.lastname: Zhigang
authors.affiliation: Institute of Health and Environmental Medicine, Tianjin Key Laboratory of Risk Assessment and Control for Environment and Food Safety, Tianjin 300050, China.
authors.forename: Chen
authors.initials: C
authors.lastname: Zhiqiang
authors.affiliation: Institute of Health and Environmental Medicine, Tianjin Key Laboratory of Risk Assessment and Control for Environment and Food Safety, Tianjin 300050, China.
authors.forename: Li
authors.initials: L
authors.lastname: Junwen
authors.affiliation: Institute of Health and Environmental Medicine, Tianjin Key Laboratory of Risk Assessment and Control for Environment and Food Safety, Tianjin 300050, China.
authors.forename: Gong
authors.initials: G
authors.lastname: Taishi
authors.affiliation: Institute of Health and Environmental Medicine, Tianjin Key Laboratory of Risk Assessment and Control for Environment and Food Safety, Tianjin 300050, China.
authors.forename: Zou
authors.initials: Z
authors.lastname: Wenci
authors.affiliation: Institute of Health and Environmental Medicine, Tianjin Key Laboratory of Risk Assessment and Control for Environment and Food Safety, Tianjin 300050, China.
authors.forename: Wang
authors.initials: W
authors.lastname: Jingfeng
mesh_terms: D001419:Bacteria / Q000378:metabolism*; D018533:Biomass; D019149:Bioreactors; D002244:Carbon / Q000737:chemistry / Q000378:metabolism; D058645:Denaturing Gradient Gel Electrophoresis; D058440:Denitrification; D006003:Glycogen / Q000378:metabolism*; D017404:In Situ Hybridization, Fluorescence; D008855:Microscopy, Electron, Scanning; D009584:Nitrogen / Q000737:chemistry / Q000378:metabolism; D010758:Phosphorus / Q000737:chemistry / Q000378:metabolism; D020560:Proteobacteria / Q000235:genetics / Q000378:metabolism; D012722:Sewage / Q000737:chemistry* / Q000382:microbiology
chemical_list: D012722:Sewage; D010758:Phosphorus; D002244:Carbon; D006003:Glycogen; D009584:Nitrogen