title: Bacterial communities in different locations, seasons and segments of a dairy wastewater treatment system consisting of six segments.
abstract: A dairy wastewater treatment system composed of the 1st segment (no aeration) equipped with a facility for the destruction of milk fat particles, four successive aerobic treatment segments with activated sludge and a final sludge settlement segment was developed. The activated sludge is circulated through the six segments by settling sediments (activated sludge) in the 6th segment and sending the sediments beck to the 1st and 2nd segments. Microbiota was examined using samples from the non-aerated 1st and aerated 2nd segments obtained from two farms using the same system in summer or winter. Principal component analysis showed that the change in microbiota from the 1st to 2nd segments concomitant with effective wastewater treatment is affected by the concentrations of activated sludge and organic matter (biological oxygen demand [BOD]), and dissolved oxygen (DO) content. Microbiota from five segments (1st and four successive aerobic segments) in one location was also examined. Although the activated sludge is circulating throughout all the segments, microbiota fluctuation was observed. The observed successive changes in microbiota reflected the changes in the concentrations of organic matter and other physicochemical conditions (such as DO), suggesting that the microbiota is flexibly changeable depending on the environmental condition in the segments. The genera Dechloromonas, Zoogloea and Leptothrix are frequently observed in this wastewater treatment system throughout the analyses of microbiota in this study.
authors: Bioproduction Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), 2-17-2-1 Tsukisamu-Higashi, Toyohira-ku, Sapporo 062-8517, Japan.
authors: Kikue
authors: K
authors: Hirota
authors: Bioproduction Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), 2-17-2-1 Tsukisamu-Higashi, Toyohira-ku, Sapporo 062-8517, Japan.
authors: Yuji
authors: Y
authors: Yokota
authors: ACT Corporation, 21-5 West-21 South-4, Obihiro 080-2471, Japan.
authors: Toru
authors: T
authors: Sekimura
authors: ACT Corporation, 21-5 West-21 South-4, Obihiro 080-2471, Japan.
authors: Hiroshi
authors: H
authors: Uchiumi
authors: Ibaraki University College of Agriculture, 3-21-1 Chuou, Ami-machi, Ibaraki, Japan.
authors: Yong
authors: Y
authors: Guo
authors: Ibaraki University College of Agriculture, 3-21-1 Chuou, Ami-machi, Ibaraki, Japan.
authors: Hiroyuki
authors: H
authors: Ohta
authors: Bioproduction Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), 2-17-2-1 Tsukisamu-Higashi, Toyohira-ku, Sapporo 062-8517, Japan; Laboratory of Environmental Microbiology, Graduate School of Agriculture, Hokkaido University, Kita-ku, Sapporo 060-8589, Japan. Electronic address: i.yumoto@aist.go.jp.
authors: Isao
authors: I
authors: Yumoto
mesh_terms: D001419:Bacteria / Q000145:classification*; D057919:Biological Oxygen Demand Analysis; D003612:Dairying; D004784:Environmental Monitoring; D012621:Seasons; D014865:Waste Disposal, Fluid; D062065:Wastewater / Q000382:microbiology*
chemical_list: D062065:Wastewater
keywords: Activated sludge; Bacterial community analysis; Dairy fat; Dairy wastewater