Co-Occurrence of Tetrodotoxin and Saxitoxins and Their Intra-Body Distribution in the Pufferfish <i>Canthigaster valentini</i>

• Main Authors: Hongchen Zhu, Takayuki Sonoyama, Misako Yamada, Wei Gao, Ryohei Tatsuno, Tomohiro Takatani, Osamu Arakawa
• Format: Article
• Language: English
• Published: MDPI AG 2020-07-01
• Series: Toxins
• Subjects: tetrodotoxin (TTX); saxitoxin (STX); pufferfish; <i>Canthigaster valentini</i>
• Online Access: https://www.mdpi.com/2072-6651/12/7/436

Pufferfish of the family Tetraodontidae possess tetrodotoxin (TTX) and/or saxitoxins (STXs), but the toxin ratio differs, depending on the genus or species. In the present study, to clarify the distribution profile of TTX and STXs in Tetraodontidae, we investigated the composition and intra-body distribution of the toxins in <i>Canthigaster valentini</i>. <i>C. valentini</i> specimens (four male and six female) were collected from Amami-Oshima Island, Kagoshima Prefecture, Japan, and the toxins were extracted from the muscle, liver, intestine, gallbladder, gonads, and skin. Analysis of the extracts for TTX by liquid chromatography tandem mass spectrometry and of STXs by high-performance liquid chromatography with post-column fluorescence derivatization revealed TTX, as well as a large amount of STXs, with neoSTX as the main component and dicarbamoylSTX and STX itself as minor components, in the skin and ovary. The toxins were also detected in the other tissues, but in much lower amounts than in the skin and ovary. The TTX/STX ratio varied greatly, depending on the tissue, but TTX was the major toxin component in the whole body, and STXs accounted for 25% and 13% of the total toxin amount in males and females, respectively. Like the marine pufferfish of the genus <i>Arothron</i>, <i>C. valentini</i> should be considered a pufferfish with considerable amounts of both TTX and STXs present simultaneously.