title: Protective effects of ectoine on behavioral, physiological and biochemical parameters of Daphnia magna subjected to hydrogen peroxide.
abstract: Ectoine (ECT) is an osmoprotectant produced by halophilic microorganisms inducing protective effects against various stressful factors. However, little is known about its influence on aquatic invertebrates subjected to hydrogen peroxide (H2O2)-a commonly used oxidative disinfectant. Therefore, the aim of our study was to determine the effects of H2O2 alone (at 5 and 10 mg/L) and in the combination with various concentrations of ECT (5, 10 and 25 mg/L) on behavioral, physiological and biochemical parameters of Daphnia magna. The following endpoints were determined: mortality, heart rate, thoracic limb movement, total glutathione (GSH)/oxidized glutathione (GSSG) ratio, catalase (CAT) activity and nitric oxide (NOx) level. The study showed that daphnids exposed to the combination of H2O2+ECT showed decreased mortality, attenuated inhibition of heart rate and thoracic limb activity, less decreased GSH/GSSG ratio, lower stimulation of CAT activity and NOx level when compared to the crustaceans exposed to H2O2 alone. The most pronounced alleviation of toxic effects was observed in the combination of 5 mg/L H2O2+25 mg/L ECT. The results suggest that protective effects of ECT in D. magna subjected to H2O2 may be related to antioxidative properties of the osmoprotectant.
authors.affiliation: Department of Physiology and Ecotoxicology, Faculty of Biotechnology and Environmental Sciences, The John Paul II Catholic University of Lublin, Kontstantynów 1 "I", 20-708 Lublin, Poland.
authors.forename: Adam
authors.initials: A
authors.lastname: Bownik
authors.affiliation: Department of Biochemistry and Enironmental Chemistry, Faculty of Biotechnology and Environmental Sciences, The John Paul II Catholic University of Lublin, Kontstantynów 1 "I", 20-708 Lublin, Poland. Electronic address: adambownik@wp.pl.
authors.forename: Zofia
authors.initials: Z
authors.lastname: Stępniewska
mesh_terms: D000599:Amino Acids, Diamino / Q000494:pharmacology*; D000818:Animals; D003621:Daphnia / Q000187:drug effects* / Q000378:metabolism; D004305:Dose-Response Relationship, Drug; D006339:Heart Rate / Q000187:drug effects* / Q000502:physiology; D006861:Hydrogen Peroxide / Q000633:toxicity*; D018384:Oxidative Stress / Q000187:drug effects* / Q000502:physiology; D020011:Protective Agents / Q000494:pharmacology*; D013550:Swimming / Q000502:physiology
chemical_list: D000599:Amino Acids, Diamino; D020011:Protective Agents; C045628:ectoine; D006861:Hydrogen Peroxide
keywords: Catalase; Daphnia; Ectoine; Glutathione; Hydrogen peroxide; Nitric oxide; Oxidative stress