Promotion of oxidative stress in the aquatic macrophyte Ceratophyllum demersum during biotransformation of the cyanobacterial toxin microcystin-LR.

摘要: Cyanobacterial toxins have been shown to adverse effects on mammals, birds and fish are therefore being increasingly recognised as a potent stress health hazard factor in aquatic ecosystems. Microcystins, which cyclic heptapeptides main group of the cyanotoxins, mainly retained within producer-cells during cyanobacterial bloom development. However, these released into surrounding medium by senescence lysis blooms. The could then come contact with wide range organisms including invertebrates, plants. In many organisms, biotransformation will take place via several glutathione-related conjugate. During process toxin conjugate broken down, formation reactive oxygen species might occur. These activate antioxidant enzymes such superoxide dismutase, catalase, ascorbate peroxidase also influence glutathione-ascorbate cycle. Aim this study was investigate glutathione-conjugate, activation glutathione S-transferases elevation giving evidence for promotion oxidative microcystins. exposure Ceratophyllum demersum microcystin-LR an concentration 5.0 microg/L, microsomal cytosolic S-transferase measured, showing beginning glutathione-toxin dismutase well parallel hydrogen peroxide level increased plant. Other detoxifiying were elevated pool, expressed reduced disulfide changed accordingly.