Asakawa M, Toyoshima T, Shida Y, Noguchi T, Miyazawa K
Faculty of Applied Biological Science, Hiroshima University, Higashi-Hiroshima, Japan.
Toxicon. 2000 Jun;38(6):763-73. doi: 10.1016/s0041-0101(99)00172-5.
In 1998, during the surveillance of the toxicity of various marine fouling organisms in Hiroshima Bay, Hiroshima Prefecture, Japan, specimens of the ribbon worm, "himomushi" Cephalothrix sp. (Nemertean) adherent to the shells of cultured oysters hanging onto floating culture rafts were found to contain toxins which showed strong paralytic action in mice throughout the survey period, February to May. The maximum toxicity (as tetrodotoxin, TTX) was 14,734 MU/g whole body. Attempts were made to identify the paralytic toxins in this worm. The "himomushi" toxin (HMT) was extracted from the worm with 80% methanol acidified with acetic acid and the extract defatted with dichloromethane. The aqueous layer was chromatographed on activated charcoal and the unbound and bound toxic fractions were analyzed by high-performance liquid chromatography and gas chromatography-mass spectrometry. It was rather unexpectedly revealed from these results that HMT was comprised of TTX, 4-epiTTX, anhydroTTX and three unidentified toxins. To our knowledge, this is the first report of the occurrence of toxic organisms, containing a high concentration of TTX, adherent to cultured bivalves such as oysters.
1998年，在日本广岛县广岛湾对各种海洋污损生物的毒性监测过程中，发现附着在悬挂于浮式养殖筏上的养殖牡蛎壳上的带状蠕虫“蛭形虫”（Cephalothrix sp.，纽形动物门）标本在整个调查期间（2月至5月）均含有对小鼠表现出强烈麻痹作用的毒素。最大毒性（以河豚毒素，TTX计）为14,734鼠单位/克全身。人们尝试鉴定这种蠕虫中的麻痹性毒素。用乙酸酸化的80%甲醇从蠕虫中提取“蛭形虫毒素”（HMT），并用二氯甲烷对提取物进行脱脂处理。水层在活性炭上进行色谱分离，未结合和结合的有毒馏分通过高效液相色谱和气相色谱 - 质谱联用进行分析。从这些结果相当意外地发现，HMT由TTX、4 - 表TTX、脱水TTX和三种未鉴定的毒素组成。据我们所知，这是首次报道附着在养殖双壳贝类如牡蛎上的含有高浓度TTX的有毒生物的出现。
