Reactive oxygen species as causative agents in the ichthyotoxicity of the red tide dinoflagellate Cochlodinium polykrikoides |
| |
Authors: | Kim, Chang Sook Lee, Sam Geun Lee, Chang Kyu Kim, Hak Gyoon Jung, Jin |
| |
Affiliation: | Harmful Algal Biology Division, National Fisheries Research and Development Institute, Pusan 619-900 and 1 Division of Applied Biology and Chemistry, College of Agriculture and Life Sciences, Seoul National University, Suwon 441-744, Korea |
| |
Abstract: | The underlying toxic mechanisms of the red tide dinoflagellate,Cochlodinium polykrikoides, were studied with respect to thereactive oxygen species-mediated toxic effect. Cochlodiniumpolykrikoides generates superoxide anion (O2) and hydrogenperoxide (H2O2), as measured by the cytochrome c reduction methodand scopoletinperoxidase method, respectively. The capabilityof C.polykrikoides to generate these oxygen radicals was relatedto the growth phase: the highest rate in the exponential phaseand a gradual decrease in the stationary phase. Other phytoplankton,such as Eutreptiella gymnastica, Heterosigma akashiwo, Prorocentrummicans, Gymnodinium sanguineum and Alexandrium tamarense, alsoproduce H2O2; the rate of H2O2 generation by these species waslower than that of C.polykrikoides. The exposure of liposomalsamples to intact or ruptured individuals of C.polykrikoidesresulted in severe membrane damage, such as liposomal lipidperoxidation. Cochlodinium polykrikoides-induced lipid peroxidationwas significantly reduced by oxygen radical scavengers, superoxidedismutase, benzoquinone, catalase and mannitol. In addition,lipid peroxidation of gill tissue of flatfish exposed to C.polykrikoidesincreased with increasing algal cell density. These resultssuggest that reactive oxygen species generated from C.polykrikoidesare responsible for oxidative damage leading to fish kills. |
| |
Keywords: | |
本文献已被 Oxford 等数据库收录! |
|