Microbioassay for the analysis of toxic factors produced by red tide phytoplankton

赤潮是严重的环境问题之一。为探讨赤潮生物的毒性机制，进行了对鱼类或贝类的直接暴露实验。然而，这种暴露实验通常需要特殊的动物饲养设施和浮游植物的大规模培养。使用适当的培养细胞作为整个活动物的替代品似乎是一个很有前途的策略。我们评价了乳酸脱氢酶(LDH)释放法作为一种在细胞水平上评估有害藻类的毒性潜力的简单方法。对轮虫有较高毒性和溶血活性的米氏卡氏杆菌(Suo-1)活细胞悬液诱导所有细胞株在细胞密度和时间依赖的方式下释放显著水平的乳酸脱氢酶，而对轮虫毒性较小且溶血活性较低的另一株米氏卡氏杆菌(Fuk)则表现出较低的活性。

Harmful algal blooms (HABs) are one of serious environmental problems. To investigate the toxic mechanism of HABs species, direct exposure experiments against fish or shellfish have been conducted. However, such exposure experiments generally require special animal rearing facilities and mass-culture of phytoplankton. Usage of appropriate cultured cells as an alternative for whole living animals seems to be a promising strategy. We evaluated lactate dehydrogenase (LDH)-release assay as a simple estimation method for toxic potential of harmful algal species at cellular level. Live cell suspension of Karenia mikimotoi (strain SUO-1), which is highly toxic to rotifer and has potent hemolytic activity, induced the release of significant levels of LDH from all the cell lines tested in cell-density and time-dependent manners, whereas another strain of K. mikimotoi (strain FUK), which is less-toxic to rotifer and has low hemolytic activity, showed fairly low activities.