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Dr. Tomohiro Takatani
Nagasaki University

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0 Tetrodotoxin
0 Marine Toxins
0 Food hygiene
0 biotoxins
0 HPLC analysis

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Journal article
Published: 30 October 2020 in Toxins
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The species classification of Cambodian freshwater pufferfish is incomplete and confusing, and scientific information on their toxicity and toxin profile is limited. In the present study, to accumulate information on the phylogeny and toxin profile of freshwater pufferfish, and to contribute to food safety in Cambodia, we conducted simultaneous genetic-based phylogenetic and toxin analyses using freshwater pufferfish individuals collected from Phnom Penh and Kratie (designated PNH and KTI, respectively). Phylogenetic analysis of partial sequences of three mitochondrial genes (cytochrome b, 16S rRNA, and cytochrome c oxidase subunit I) determined for each fish revealed that PNH and KTI are different species in the genus Pao (designated Pao sp. A and Pao sp. B, respectively). A partial sequence of the nuclear tributyltin-binding protein type 2 (TBT-bp2) gene differentiated the species at the amino acid level. Instrumental analysis of the toxin profile revealed that both Pao sp. A and Pao sp. B possess saxitoxins (STXs), comprising STX as the main component. In Pao sp. A, the toxin concentration in each tissue was extremely high, far exceeding the regulatory limit for STXs set by the Codex Committee, whereas in Pao sp. B, only the skin contained high toxin concentrations. The difference in the STX accumulation ability between the two species with different TBT-bp2 sequences suggests that TBT-bp2 is involved in STX accumulation in freshwater pufferfish.

ACS Style

Hongchen Zhu; Akinori Yamada; Yui Goto; Linan Horn; Laymithuna Ngy; Minoru Wada; Hiroyuki Doi; Jong Lee; Tomohiro Takatani; Osamu Arakawa. Phylogeny and Toxin Profile of Freshwater Pufferfish (Genus Pao) Collected from 2 Different Regions in Cambodia. Toxins 2020, 12, 689 .

AMA Style

Hongchen Zhu, Akinori Yamada, Yui Goto, Linan Horn, Laymithuna Ngy, Minoru Wada, Hiroyuki Doi, Jong Lee, Tomohiro Takatani, Osamu Arakawa. Phylogeny and Toxin Profile of Freshwater Pufferfish (Genus Pao) Collected from 2 Different Regions in Cambodia. Toxins. 2020; 12 (11):689.

Chicago/Turabian Style

Hongchen Zhu; Akinori Yamada; Yui Goto; Linan Horn; Laymithuna Ngy; Minoru Wada; Hiroyuki Doi; Jong Lee; Tomohiro Takatani; Osamu Arakawa. 2020. "Phylogeny and Toxin Profile of Freshwater Pufferfish (Genus Pao) Collected from 2 Different Regions in Cambodia." Toxins 12, no. 11: 689.

Journal article
Published: 07 July 2020 in Toxins
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Paralytic shellfish toxins (PSTs) produced by Alexandrium catenella (formerly A. tamarense) in Korean coastal waters caused the deaths of four people (in 1986 and 1996) who consumed contaminated mussels (Mytilus edulis). This led to more detailed consideration of the risks of PST outbreaks and incidents in Korea, including the introduction of shellfish collection bans. In this study, we investigated the relationships between A. catenella population dynamics and PST accumulation in the mussel M. galloprovincialis. Discharges from the Nakdong River affect the environmental conditions along the Geoje coast, resulting in low salinity and high nutrient levels that trigger blooms of A. catenella. At the toxin peak on 24 April 2017, the toxins detected in A. catenella cells were C1, gonyautoxin (GTX)1 and GTX2, whereas the concentrations of PSTs in M. galloprovincialis were high and in the order of GTX4 > GTX1 > GTX3 > saxitoxin (STX) > GTX2 > neoSTX > decarbamoylgonyautoxin (dcGTX)2 > dc GTX3. The PST level in mussels was also high. At 15 °C, the PSTs are constantly found to be higher (10-fold higher in 2017 and 30-fold higher in 2018) than safe levels for human consumption (80 μg STX diHCl equivalents 100 g−1).

ACS Style

Seung Ho Baek; Jungmin Choi; Minji Lee; Bum Soo Park; Yuchengmin Zhang; Osamu Arakawa; Tomohiro Takatani; Joong-Kyun Jeon; Young Ok Kim. Change in Paralytic Shellfish Toxins in the Mussel Mytilus galloprovincialis Depending on Dynamics of Harmful Alexandrium catenella (Group I) in the Geoje Coast (South Korea) during Bloom Season. Toxins 2020, 12, 442 .

AMA Style

Seung Ho Baek, Jungmin Choi, Minji Lee, Bum Soo Park, Yuchengmin Zhang, Osamu Arakawa, Tomohiro Takatani, Joong-Kyun Jeon, Young Ok Kim. Change in Paralytic Shellfish Toxins in the Mussel Mytilus galloprovincialis Depending on Dynamics of Harmful Alexandrium catenella (Group I) in the Geoje Coast (South Korea) during Bloom Season. Toxins. 2020; 12 (7):442.

Chicago/Turabian Style

Seung Ho Baek; Jungmin Choi; Minji Lee; Bum Soo Park; Yuchengmin Zhang; Osamu Arakawa; Tomohiro Takatani; Joong-Kyun Jeon; Young Ok Kim. 2020. "Change in Paralytic Shellfish Toxins in the Mussel Mytilus galloprovincialis Depending on Dynamics of Harmful Alexandrium catenella (Group I) in the Geoje Coast (South Korea) during Bloom Season." Toxins 12, no. 7: 442.

Journal article
Published: 03 July 2020 in Toxins
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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 Canthigaster valentini. C. valentini 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 Arothron, C. valentini should be considered a pufferfish with considerable amounts of both TTX and STXs present simultaneously.

ACS Style

Hongchen Zhu; Takayuki Sonoyama; Misako Yamada; Wei Gao; Ryohei Tatsuno; Tomohiro Takatani; Osamu Arakawa. Co-Occurrence of Tetrodotoxin and Saxitoxins and Their Intra-Body Distribution in the Pufferfish Canthigaster valentini. Toxins 2020, 12, 436 .

AMA Style

Hongchen Zhu, Takayuki Sonoyama, Misako Yamada, Wei Gao, Ryohei Tatsuno, Tomohiro Takatani, Osamu Arakawa. Co-Occurrence of Tetrodotoxin and Saxitoxins and Their Intra-Body Distribution in the Pufferfish Canthigaster valentini. Toxins. 2020; 12 (7):436.

Chicago/Turabian Style

Hongchen Zhu; Takayuki Sonoyama; Misako Yamada; Wei Gao; Ryohei Tatsuno; Tomohiro Takatani; Osamu Arakawa. 2020. "Co-Occurrence of Tetrodotoxin and Saxitoxins and Their Intra-Body Distribution in the Pufferfish Canthigaster valentini." Toxins 12, no. 7: 436.

Journal article
Published: 10 August 2019 in Toxins
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To clarify the differences in toxin selectivity between marine and freshwater pufferfish, we conducted experiments in artificially reared nontoxic specimens of Takifugu pardalis (marine) and Pao suvattii (freshwater) using tetrodotoxin (TTX) and paralytic shellfish poison (PSP; decarbamoylsaxitoxin (dcSTX) or saxitoxin (STX)). T. pardalis specimens were administered feed homogenate containing TTX or dcSTX (dose of toxin, 55.2 nmol/fish) and P. suvattii specimens were administered feed homogenate containing TTX + STX (dose of each toxin, 19.2 nmol/fish) by oral gavage. The toxin content in the intestine, muscle, skin, liver, and gonads was quantified after 24 and 48 or 72 h. In T. pardalis, TTX administered into the intestine was absorbed into the body and transferred and retained mainly in the skin and liver, while dcSTX was hardly retained in the body, although it partly remained in the intestine. In strong contrast, in P. suvattii, little TTX remained in the body, whereas STX was absorbed into the body and was transferred and retained in the ovary and skin. The findings revealed that TTX/PSP selectivity differs between the marine species T. pardalis and the freshwater species P. suvattii. T. pardalis, which naturally harbors TTX, selectively accumulates TTX, and P. suvattii, which naturally harbors PSP, selectively accumulates PSP.

ACS Style

Wei Gao; Yoko Kanahara; Misako Yamada; Ryohei Tatsuno; Hiroyuki Yoshikawa; Hiroyuki Doi; Tomohiro Takatani; Osamu Arakawa. Contrasting Toxin Selectivity between the Marine Pufferfish Takifugu pardalis and the Freshwater Pufferfish Pao suvattii. Toxins 2019, 11, 470 .

AMA Style

Wei Gao, Yoko Kanahara, Misako Yamada, Ryohei Tatsuno, Hiroyuki Yoshikawa, Hiroyuki Doi, Tomohiro Takatani, Osamu Arakawa. Contrasting Toxin Selectivity between the Marine Pufferfish Takifugu pardalis and the Freshwater Pufferfish Pao suvattii. Toxins. 2019; 11 (8):470.

Chicago/Turabian Style

Wei Gao; Yoko Kanahara; Misako Yamada; Ryohei Tatsuno; Hiroyuki Yoshikawa; Hiroyuki Doi; Tomohiro Takatani; Osamu Arakawa. 2019. "Contrasting Toxin Selectivity between the Marine Pufferfish Takifugu pardalis and the Freshwater Pufferfish Pao suvattii." Toxins 11, no. 8: 470.