title: Isolation, identification, and algicidal activity of aerobic denitrifying bacterium R11 and its effect on Microcystis aeruginosa.
abstract: Recently, algicidal bacteria have attracted attention as possible agents for the inhibition of algal water blooms. In this study, an aerobic denitrifying bacterium, R11, with high algicidal activity against the toxic Microcystis aeruginosa was isolated from lake sediments. Based on its physiological characteristics and 16S rRNA gene sequence, it was identified as Raoultella, indicating that the bacterium R11 has a good denitrifying ability at 30 °C and can reduce the concentration of nitrate-N completely within 36 h. Additionally, different algicidal characteristics against Microcystis aeruginosa were tested. The results showed that the initial bacterial cell density and algal cell densities strongly influence the removal rates of chlorophyll a. Algicidal activity increased with an increase in the bacterial cell density. With densities of bacterial culture at over 2.4 × 10(5) cell/mL, algicidal activity of up to 80% was obtained in 4 days. We have demonstrated that, with the low initial algal cell density (OD680 less than 0.220), the algicidal activity reached was higher than 90% after 6 days.
authors.affiliation: School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China; State Key Laboratory of Urban Water Resource and Environment, School of Municipal and Environmental Engineering, Harbin Institute of Technology, Harbin 150090, China E-mail: mafang@hit.edu.cn.
authors.forename: Jun-feng
authors.initials: JF
authors.lastname: Su
authors.affiliation: School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China.
authors.forename: Si-cheng
authors.initials: SC
authors.lastname: Shao
authors.affiliation: School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China.
authors.forename: Ting-lin
authors.initials: TL
authors.lastname: Huang
authors.affiliation: State Key Laboratory of Urban Water Resource and Environment, School of Municipal and Environmental Engineering, Harbin Institute of Technology, Harbin 150090, China E-mail: mafang@hit.edu.cn.
authors.forename: Fang
authors.initials: F
authors.lastname: Ma
authors.affiliation: School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China.
authors.forename: Kai
authors.initials: K
authors.lastname: Zhang
authors.affiliation: School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China.
authors.forename: Gang
authors.initials: G
authors.lastname: Wen
authors.affiliation: School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China.
authors.forename: Sheng-chen
authors.initials: SC
authors.lastname: Zheng
mesh_terms: D000898:Antibiosis; D002734:Chlorophyll / Q000032:analysis; D000077194:Chlorophyll A; D058440:Denitrification; D004755:Enterobacteriaceae / Q000502:physiology*; D005068:Eutrophication; D060106:Lakes / Q000382:microbiology; D046931:Microcystis; D012336:RNA, Ribosomal, 16S / Q000235:genetics
chemical_list: D012336:RNA, Ribosomal, 16S; D002734:Chlorophyll; D000077194:Chlorophyll A