|
|||||
|
|
Toxicity of complex cyanobacterial samples and their fractions in Xenopus laevis embryos and the role of microcystins |
|
| Authors: | Burýsková Blanka Hilscherová Klára Babica Pavel Vrsková Dagmar Marsálek Blahoslav Bláha Ludek |
| Affiliation: | aCentre for Cyanobacteria and their Toxins, Institute of Botany, Czech Academy of Science and RECETOX, Masaryk University, Kamenice 3, CZ62500 Brno, Czech Republic bDepartment of Biology and Wildlife Diseases, University of Veterinary and Pharmaceutical Sciences, Palackého 1-3, CZ61242 Brno, Czech Republic cDepartment of Pharmacology, Faculty of Medicine, Masaryk University, Komenského nám. 2, CZ66243 Brno, Czech Republic |
| Abstract: | This work evaluated the effects of various cyanobacterial fractions in Frog Embryo Teratogenesis Assay Xenopus (FETAX) with African clawed frog embryos. Fractions were prepared from five biomasses with different dominant genera (Microcystis, Aphanizomenon, Anabaena, Planktothrix) and different microcystin content. Effects of following fractions were investigated: (I) homogenate of complex cyanobacterial biomass, (II) cell debris (pellet) after centrifugation of complex biomass, (III) supernatant after centrifugation of complex biomass (=crude aqueous extract), (IV) permeate after passing of crude extract through C-18 column (fraction devoid of microcystins), and (V) eluate from C-18 column (containing microcystins, if present). Besides classical parameters evaluated in 96 h FETAX (mortality, growth inhibition, malformations), we have also assessed the effects on biochemical markers of oxidative stress and detoxification (glutathione pool, GSH; activity of glutathione peroxidase, GPx; glutathione reductase, GR; activity of glutathione-S-transferase, GST). Complex biomass (I) and aqueous extract (III) were generally the most toxic fractions in terms of mortality and growth inhibition, whereas eluates containing microcystins (V) were generally less toxic. On the other hand, the same fraction (eluates) induced significant malformations in low concentrations but the effects were not related to the content of microcystins. Biomarkers were affected in variable manner but no significant effect or clear relation to microcystin content was observed. Our data support the hypothesis that microcystins are not the only or major toxic compounds in the complex cyanobacterial samples (at least for some species) and that more attention should be paid to other components of complex cyanobacterial biomass including non-specific parameters such as oxygen content or toxic ammonia released during bacterial decay of organic material. |
| Keywords: | FETAX Xenopus laevis Malformations Cyanobacterial fractions Biomarkers |
| 本文献已被 ScienceDirect PubMed 等数据库收录！ | |