title: Growth, physiochemical and antioxidant responses of overwintering benthic cyanobacteria to hydrogen peroxide.
abstract: The recruitment of overwintering benthic cyanobacteria from the sediment surface is important for the development of cyanobacterial blooms during warm spring seasons. Thus, controlling the growth of cyanobacteria at the benthic stage to inhibit their recruitment is vital to control or delay the formation of summer blooms. In this study, overwintering benthic cyanobacteria were exposed to ascending hydrogen peroxide (H2O2) concentrations (0, 1, 5, and 20 mg/L) in a simulated overwintering environment. Photosynthetic pigments, physiochemical features, and antioxidant responses were evaluated to determine the inhibitory effects of H2O2on the growth of benthic cyanobacteria and to identify the potential mechanisms thereof. These H2O2-treated cyanobacteria were then collected through filtration and transferred to an optimum environment to evaluate their recovery capacity. The results showed that chlorophyll a and phycocyanin contents, photosynthetic yield, and esterase activity decreased significantly in H2O2treated groups compared to the control. The activities of superoxide dismutase (SOD) and catalase (CAT) in benthic cyanobacteria were inhibited after 72 h exposure to H2O2, while the malondialdehyde (MDA) contents were stimulated at the same time. These results indicate that H2O2can inhibit the growth of benthic cyanobacteria, and H2O2-induced oxidative damage might be one of the mechanisms involved. The recovery experiment showed that the impairment of benthic cyanobacteria was temporary at a low dose of 1 mg/L H2O2, but permanent damage was induced when H2O2concentrations were increased to 5 and 20 mg/L. Overall, our results highlight that H2O2is a potential cyanobacteria inhibitor and can be used to decreasing the biomass of overwintering cyanobacteria, and could further control the intensity of cyanobacteria during the growth seasons.
authors.affiliation: State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, 73 East Beijing Road, Nanjing, 210008, China; College of Resources and Environment, University of Chinese Academy of Sciences, Beijing, 100049, China.
authors.forename: Chao
authors.initials: C
authors.lastname: Chen
authors.affiliation: State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, 73 East Beijing Road, Nanjing, 210008, China.
authors.forename: Zhen
authors.initials: Z
authors.lastname: Yang
authors.affiliation: State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, 73 East Beijing Road, Nanjing, 210008, China.
authors.forename: Fanxiang
authors.initials: F
authors.lastname: Kong
authors.affiliation: State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, 73 East Beijing Road, Nanjing, 210008, China.
authors.forename: Min
authors.initials: M
authors.lastname: Zhang
authors.affiliation: State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, 73 East Beijing Road, Nanjing, 210008, China.
authors.forename: Yang
authors.initials: Y
authors.lastname: Yu
authors.affiliation: State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, 73 East Beijing Road, Nanjing, 210008, China. Electronic address: xlshi@niglas.ac.cn.
authors.forename: Xiaoli
authors.initials: X
authors.lastname: Shi
mesh_terms: D000975:Antioxidants / Q000378:metabolism*; D018533:Biomass; D002374:Catalase / Q000378:metabolism; D002734:Chlorophyll / Q000378:metabolism; D000077194:Chlorophyll A; D000458:Cyanobacteria / Q000378:metabolism; D004950:Esterases / Q000378:metabolism; D006861:Hydrogen Peroxide / Q000494:pharmacology*; D008315:Malondialdehyde / Q000378:metabolism; D018384:Oxidative Stress / Q000187:drug effects; D010788:Photosynthesis / Q000187:drug effects; D010798:Phycocyanin / Q000378:metabolism; D010839:Phytoplankton / Q000187:drug effects* / Q000201:enzymology / Q000254:growth & development* / Q000378:metabolism; D012621:Seasons; D013482:Superoxide Dismutase / Q000378:metabolism
chemical_list: D000975:Antioxidants; D010798:Phycocyanin; D002734:Chlorophyll; D008315:Malondialdehyde; D006861:Hydrogen Peroxide; D002374:Catalase; D013482:Superoxide Dismutase; D004950:Esterases; D000077194:Chlorophyll A
keywords: Algicide; Benthic cyanobacteria; Hydrogen peroxide; Oxidative damage; Recovery capability