Tetrodotoxins in Ribbon Worms Cephalothrix cf. simula and Kulikovia alborostrata from Peter the Great Bay, Sea of Japan

Abstract

Tetrodotoxin, an extremely potent low-molecular-weight neurotoxin, and its analogues (TTXs) are widely distributed in aquatic and terrestrial ecosystems. Most investigations concerning TTXs have been conducted mainly on puffer fish, octopus, and mollusks, without paying due attention to various non-edible animals including nemerteans, a small group of marine worms, several species of which have been shown to possess high amounts of TTXs. In this study, for the first time, variations in TTX and its analogues, in 32 specimens of Cephalothrix cf. simula and 36 specimens of Kulikovia alborostrata, from Peter the Great Bay Sea of Japan were investigated, which may contribute to elucidation of TTXs migration pathways in ecosystems. Using high performance liquid chromatography with tandem mass spectrometry (HPLC–MS/MS), it was found that the total TTXs concentrations within both species vary by one to several orders of magnitude, 85.75–7108.26 µg/g and 0.35–8.11 ng/g in C. cf. simula and K. alborostrata, respectively. The intra- and interspecies similarities in proportions of TTXs in both species were observed; based on the results, a possible way of their toxification was discussed.

Tetrodotoxin Profiles in Xanthid Crab Atergatis floridus and Blue-Lined Octopus Hapalochlaena cf. fasciata from the Same Site in Nagasaki, Japan

“…fasciata as the source of TTX. This suggestion is supported by reports that the possession of similar major toxins in several different organisms, such as two species of ribbon worm [ 38 ], pufferfish and goby [ 39 ], suggests the presence of a common prey. TTX is thought to accumulate in higher trophic levels through the food chain starting from the TTX-producing bacteria [ 7 , 9 ].…”

“…), bivalves, gastropods, animal tissues, and sand were preferentially found in the stomach contents of A. floridus collected on the Miura Peninsula in Japan [ 44 ], so it is not surprising that octopuses and A. floridus feed on the same food. There are many reports about organisms of lower trophic levels, such as snails, ribbon worms, and flatworms, around the world that contain TTX and non-equilibrium analogs [ 38 , 45 , 46 , 47 , 48 ]. Since bacteria and lower trophic levels of organisms were not investigated in this study, it is necessary to search for organisms that are sources of toxins in the bodies of TTX-bearing organisms and in the surrounding environment in this site in the future.…”

Japanese Planocerid Flatworms: Difference in Composition of Tetrodotoxin and Its Analogs and the Effects of Ingestion by Toxin-Bearing Fishes in the Ryukyu Islands, Japan

“…The 5,6,11-trideoxyTTX has been reported to be dominantly high in a variety of organisms (Rambla-Alegre et al 2017 ; Suo et al 2021 , 2022 , 2024 ; Ito et al 2022 , 2023 ; Vlasenko and Magarlamov 2020 , 2022 ). Recently, TTX/5,6,11-trideoxyTTX ratios of pufferfish, including C. patoca , collected throughout the Japanese Archipelago, ranged from 2 to 5 regardless of species or region.…”