Possible Factors Responsible for the Fish-Killing Mechanisms of the Red Tide Phytoplankton, Chattonella marina and Cochlodinium polykrikoides

摘要: Generation of reactive oxygen species (ROS) such as superoxide (O2 –) and hydroxyl radical (·OH) by Chattonella marina could be confirmed ESR spin trapping method. Several lines evidence suggested that cell surface structure C. marina, glycocalyx, has NADPH-dependent O2 – generation system. Immunohistochemical analysis gill lamellae from yellowtail exposed to using antiserum against crude glycocalyx demonstrated there were the antigns recognaised on lamellae. The results suggest continuous accumulation discharged occurs during exposure, which may responsible for ROSmediated severe tissue damage leading fish death. As compare levels H2O2 detected in Cochlodinium polykrikoides trace levels. Furthermore, no significant increase was observed presence lectins or mucus prepared skin yellowtail, whereas generated increased level responding these stimuli. cell-free aqueous extract showed toxic effect HeLa cells, but had almost effect. gradual polysaccharides medium culture polykrikoides, gradually became viscous, change marina. These ichthyotoxic mechanisms are different. ROS play a role fish-killing activity case certain substances mainly toxicity rather than ROS.