title: Acclimation of Ceratophyllum demersum to stress imposed by Phragmites australis and Quercus robur leaf extracts.
abstract: Natural and anthropogenic activities lead to deposition of leaves into water bodies, releasing allelochemicals that might influence aquatic biota. Time-response experiments were performed with Ceratophyllum demersum using aqueous Quercus robur and Phragmites australis leaf extracts. The aim was to investigate the ability of C. demersum to acclimate to stress imposed by leaf extracts using antioxidative enzymes (GR, POD, GST, GPx) and photosynthesis as endpoints. Highest enzyme activity and photosynthetic reduction was observed after 24 h in both extracts. After 48 h, photosynthesis and enzyme levels were significantly different from the ones noted at 24 h. Enzyme activities, except GR, and oxygen production did not return to control levels after 1 week in Q. robur extracts. In contrast, enzyme and photosynthetic oxygen levels in P. australis extract recovered after 168 h. Results indicate that increase in antioxidative enzyme levels is part of the protection strategy of C. demersum against oxidative stress.
authors.affiliation: Leibniz Institute of Freshwater Ecology and Inland Fisheries, Biochemical Regulation, Müggelseedamm 301, 12587 Berlin, Germany.
authors.forename: Sheku
authors.initials: S
authors.lastname: Kamara
authors.forename: Stephan
authors.initials: S
authors.lastname: Pflugmacher
mesh_terms: D000064:Acclimatization; D000975:Antioxidants / Q000378:metabolism; D004305:Dose-Response Relationship, Drug; D005979:Glutathione Peroxidase / Q000378:metabolism; D005980:Glutathione Reductase / Q000378:metabolism; D005982:Glutathione Transferase / Q000378:metabolism; D019684:Magnoliopsida / Q000187:drug effects* / Q000201:enzymology / Q000378:metabolism; D018384:Oxidative Stress / Q000187:drug effects*; D010544:Peroxidases / Q000378:metabolism; D010788:Photosynthesis / Q000187:drug effects*; D010936:Plant Extracts / Q000633:toxicity; D018515:Plant Leaves; D006109:Poaceae; D029963:Quercus; D017382:Reactive Oxygen Species / Q000378:metabolism; D013997:Time Factors; D014874:Water Pollutants, Chemical / Q000633:toxicity*
chemical_list: D000975:Antioxidants; D010936:Plant Extracts; D017382:Reactive Oxygen Species; D014874:Water Pollutants, Chemical; D010544:Peroxidases; D005979:Glutathione Peroxidase; D005980:Glutathione Reductase; D005982:Glutathione Transferase