Comparative study on the toxic factors of Chochlodinium polykrikoides and Chattonella marina

用ESR自旋捕捉法证实了海洋查顿氏菌产生的ROS。用粗糖萼抗血清对暴露于滨海梭子蟹的黄尾鱼鳃片进行免疫组织化学分析，结果表明，鳃片表面有抗血清识别的抗血清。与滨海梭子藻相比，其体内的ROS含量为微量水平。此外，在黄尾鱼皮肤和鳃制备的凝集素或鱼粘液的存在下，波氏梭子藻产生的O^2-没有显著增加，而滨海梭子蟹对这些刺激产生的O^2-反应水平增加。白花蛇舌草的无细胞水提物对HeLa细胞有明显的毒性作用，而滨海金鱼提取液对HeLa细胞几乎没有影响。此外，在培养过程中观察到多糖在培养基中的逐渐积累，而在滨海梭子藻的培养中则没有观察到这种变化。这些结果表明，ROS可能在滨海梭子蟹的杀鱼活性中起着重要的作用，而对于波氏梭子藻来说，某些有毒物质或多糖是主要的毒性物质或多糖，而不是ROS。

Generation of reactive oxygen species (ROS) by Chattonella marina could be confirmed by ESR spin trapping method. Immunohistochemical analysis of gill lamellae from yellowtail exposed to C.marina using antiserum against crude glycocalyx demonstrated that there were the antigns recognaised by the antiserum on the surface of gill lamellae. As compared to C.marina, the levels of ROS detected in Cochlodinium polykrikoides were trace levels. Furthermore, no significant increase in O^2_- generation by C.polykrikoides was observed in the presence of lectins or fish mucus prepared from skin and gill of yellowtail, whereas C.marina generated increased level of O^2_- responding to these stimuli. The cell-free aqueous extract prepared from C.polykrikoides showed toxic effect on HeLa cells, but the extract of C.marina had almost no effect. Furthermore, gradual accumulation of polysaccharides in the medium was observed during the culture of C.polykrikoides, but no such change was observed in the medium of C.marina. These results suggest that ROS may play a significant role in the fish-killing activity of C.marina, whereas in the case of C.polykrikoides, certain toxic substances or polysaccharides are mainly responsible for the toxicity rather than ROS.