STUDIES ON TOXIC AGENT IN LOWER BENTHIC ANIMALS INHABITING IN THE SETO INLAND SEA, ESPECIALLY ON TETRODOTOXIN OF THE FLATWORM

为了阐明濑户内海中河豚毒素（TTX）的分布、来源及在底栖动物体内的积累机制，本研究进行了以下研究.在多棘星扇贝的各个器官中，卵巢的活力最高（最大值）。12700 MU/g），其次为消化器官。结果表明，雌鼠的总体毒性明显高于雄鼠.在多触手扁角虫的各组织中，输卵管的毒性最大，其次是消化器官。产下的卵块表现出极高的效力，高达10700 MU/g。这些结果表明，扁形虫和海星具有TTX作为防御或报警物质。从扁虫的消化道中分离到一些产TTX的细菌.褐绿扁带蠕虫（Lineus fuscoviridis）、斑点扁带虫（Tubulanus punctatus）等具有致死力。经薄层层析、高效液相色谱和气质联用等方法鉴定，该化合物为TTX及其有关物质。

In order to clarify the distribution, origin and mechanism of accumulation of tetrodotoxin (TTX) in the lower benthic animals in the Seto Inland Sea, some examinations were performed and following results were obtained.1. Among the various organs of the starfish Astropecten polyacanthus, ovary showed the highest potency (max. 12700 MU/g) followed by digestive organs. As the result, overall toxicity was remarkably higher in female than in male.2. Among the various tissues of the flatworm planocera multitentaculate, oviduct was most toxic, followed by digestive organs. The egg masses laid exhibited extremely high potency upto 10700 MU/g. These rusults suggested that the flatworm and the starfish possess TTX as defense or alarm substance against predators. Some TTX-producing bacteria were isolated from the digestive tract of flatworm.3. Ribbon worms, Lineus fuscoviridis, Tubulanus punctatus and some others, had lethal potencise. The toxios were partially purified and identified as TTX and its relating substances by TLC, HPLC and GC-MS. This may be the first finding of TTX in Nemertini.