Isolation and Characterization of Marine Toxins

A special issue of Toxins (ISSN 2072-6651). This special issue belongs to the section "Marine and Freshwater Toxins".

Deadline for manuscript submissions: closed (30 November 2020) | Viewed by 36110

Special Issue Editors

Graduate School of Healthcare, Tokyo Healthcare University
Interests: isolation and characterization of biotoxins from toxic marine organisms; analytical determination of marine biotoxins related to seafood poisonings; toxicity studies of biotoxins in shellfish and fish; paralytic shellfish poison (PSP) composition of toxic marine dinofalagellate; distribution and accumulation of tetrodotoxin in aquatic organisms; accumulation of PSP by filter-feeding and nonfilter feeding vectors in the sea
Graduate School of Integrated Sciences for Life, Hiroshima University
Interests: isolation and characterization of biotoxins from toxic marine organisms; analytical determination of marine biotoxins related to seafood poisonings; toxicity studies of biotoxins in shellfish and fish; paralytic shellfish poison (PSP) composition of toxic marine dinofalagellate; distribution and accumulation of tetrodotoxin in aquatic organisms; accumulation of PSP by filter-feeding and nonfilter feeding vectors in the sea

Special Issue Information

Dear Colleagues,

Typical fishery products such as fish and shellfish are important as human food, in particular as an animal protein source. However, some species of fish and shellfish contain toxins that may cause food poisoning to humans. Many naturally occurring biotoxins are produced in many species of organisms, including toxic microalgae species associated with “harmful algal blooms (HAB)”, such as paralytic shellfish poison (PSP)-producing dinoflagellate, and other organisms inhabiting the hydrosphere. These toxins have a severe impact on fisheries, their related industries and human health, because they can be transferred and accumulate on marine and freshwater vertebrates and invertebrates through a more complicated pathway including the food chain. This is exemplified by the paralytic shellfish poisoning of humans on eating PSP contaminated shellfish. It is necessary for us to isolate and characterize these marine biotoxins, to prevent tragic food poisoning incidents and severe damage to aquaculture around the world. This Special Issue call for papers deals with structure and analytical chemistry studies of toxins in aquatic habitats, characterization of new toxins isolated from marine and freshwater organisms, case studies of seafood poisonings, biotransformation/accumulation of toxins from aquatic organisms, and novel targets or modes of action for aquatic toxins. The editors will also consider reviews that summarize current thinking or present controversial viewpoints for further discussion. Short communications that report important self-contained observations are also welcome.

Prof. Tamao Noguchi
Prof. Manabu Asakawa
Guest Editors

Manuscript Submission Information

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Keywords

  • paralytic shellfish poison
  • tetrodotoxin
  • marine biotoxin
  • instrumental analysis
  • toxic marine phytoplankton
  • seafood poisonings
  • mass spectrometry
  • chromatography

Published Papers (10 papers)

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Research

15 pages, 2270 KiB  
Article
The Anemonia sulcata Toxin BDS-I Protects Astrocytes Exposed to Aβ1–42 Oligomers by Restoring [Ca2+]i Transients and ER Ca2+ Signaling
by Ilaria Piccialli, Valentina Tedeschi, Francesca Boscia, Roselia Ciccone, Antonella Casamassa, Valeria de Rosa, Paolo Grieco, Agnese Secondo and Anna Pannaccione
Toxins 2021, 13(1), 20; https://doi.org/10.3390/toxins13010020 - 31 Dec 2020
Cited by 6 | Viewed by 2169
Abstract
Intracellular calcium concentration ([Ca2+]i) transients in astrocytes represent a highly plastic signaling pathway underlying the communication between neurons and glial cells. However, how this important phenomenon may be compromised in Alzheimer’s disease (AD) remains unexplored. Moreover, the involvement of [...] Read more.
Intracellular calcium concentration ([Ca2+]i) transients in astrocytes represent a highly plastic signaling pathway underlying the communication between neurons and glial cells. However, how this important phenomenon may be compromised in Alzheimer’s disease (AD) remains unexplored. Moreover, the involvement of several K+ channels, including KV3.4 underlying the fast-inactivating currents, has been demonstrated in several AD models. Here, the effect of KV3.4 modulation by the marine toxin blood depressing substance-I (BDS-I) extracted from Anemonia sulcata has been studied on [Ca2+]i transients in rat primary cortical astrocytes exposed to Aβ1–42 oligomers. We showed that: (1) primary cortical astrocytes expressing KV3.4 channels displayed [Ca2+]i transients depending on the occurrence of membrane potential spikes, (2) BDS-I restored, in a dose-dependent way, [Ca2+]i transients in astrocytes exposed to Aβ1–42 oligomers (5 µM/48 h) by inhibiting hyperfunctional KV3.4 channels, (3) BDS-I counteracted Ca2+ overload into the endoplasmic reticulum (ER) induced by Aβ1–42 oligomers, (4) BDS-I prevented the expression of the ER stress markers including active caspase 12 and GRP78/BiP in astrocytes treated with Aβ1–42 oligomers, and (5) BDS-I prevented Aβ1–42-induced reactive oxygen species (ROS) production and cell suffering measured as mitochondrial activity and lactate dehydrogenase (LDH) release. Collectively, we proposed that the marine toxin BDS-I, by inhibiting the hyperfunctional KV3.4 channels and restoring [Ca2+]i oscillation frequency, prevented Aβ1–42-induced ER stress and cell suffering in astrocytes. Full article
(This article belongs to the Special Issue Isolation and Characterization of Marine Toxins)
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14 pages, 1438 KiB  
Article
Tetrodotoxin and Its Analogues in Cephalothrix cf. simula (Nemertea: Palaeonemertea) from the Sea of Japan (Peter the Great Gulf): Intrabody Distribution and Secretions
by Anna E. Vlasenko and Timur Yu. Magarlamov
Toxins 2020, 12(12), 745; https://doi.org/10.3390/toxins12120745 - 26 Nov 2020
Cited by 12 | Viewed by 1938
Abstract
Some nemertean species from the genus Cephalothrix accumulate tetrodotoxin (TTX) in extremely high concentrations. The current study is the first to provide high-performance liquid chromatography–tandem mass spectrometry (HPLC–MS/MS) data on tetrodotoxin and its analogues (TTXs) profile and concentration in different regions and organs [...] Read more.
Some nemertean species from the genus Cephalothrix accumulate tetrodotoxin (TTX) in extremely high concentrations. The current study is the first to provide high-performance liquid chromatography–tandem mass spectrometry (HPLC–MS/MS) data on tetrodotoxin and its analogues (TTXs) profile and concentration in different regions and organs of Cephalothrix cf. simula, and its secretions produced in response to stimulation. Different specimens of C. cf. simula possessed 7–11 analogues, including nine previously found in this species and two new for nemerteans—4,9-anhydro-8-epi-5,6,11-trideoxyTTX and 1-hydroxy-8-epi-5,6,11-trideoxyTTX. The study of the toxins’ distribution in different regions and organs of nemerteans revealed the same qualitative composition of TTXs throughout the body but differences in the total concentration of the toxins. The total concentration of TTXs was highest in the anterior region of the body and decreased towards the posterior; the ratio of the analogues also differed between regions. The data obtained suggest a pathway of TTXs uptake in C. cf. simula and the role of toxins in the life activity of nemerteans. Full article
(This article belongs to the Special Issue Isolation and Characterization of Marine Toxins)
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15 pages, 3095 KiB  
Article
Phylogeny and Toxin Profile of Freshwater Pufferfish (Genus Pao) Collected from 2 Different Regions in Cambodia
by Hongchen Zhu, Akinori Yamada, Yui Goto, Linan Horn, Laymithuna Ngy, Minoru Wada, Hiroyuki Doi, Jong Soo Lee, Tomohiro Takatani and Osamu Arakawa
Toxins 2020, 12(11), 689; https://doi.org/10.3390/toxins12110689 - 30 Oct 2020
Cited by 7 | Viewed by 3190
Abstract
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 [...] Read more.
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. Full article
(This article belongs to the Special Issue Isolation and Characterization of Marine Toxins)
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13 pages, 3106 KiB  
Article
In Silico Modeling of Spirolides and Gymnodimines: Determination of S Configuration at Butenolide Ring Carbon C-4
by Christian Zurhelle, Tilmann Harder, Urban Tillmann and Jan Tebben
Toxins 2020, 12(11), 685; https://doi.org/10.3390/toxins12110685 - 29 Oct 2020
Cited by 1 | Viewed by 1713
Abstract
Only few naturally occurring cyclic imines have been fully structurally elucidated or synthesized to date. The configuration at the C-4 carbon plays a pivotal role in the neurotoxicity of many of these metabolites, for example, gymnodomines (GYMs) and spirolides (SPXs). However, the stereochemistry [...] Read more.
Only few naturally occurring cyclic imines have been fully structurally elucidated or synthesized to date. The configuration at the C-4 carbon plays a pivotal role in the neurotoxicity of many of these metabolites, for example, gymnodomines (GYMs) and spirolides (SPXs). However, the stereochemistry at this position is not accessible by nuclear Overhauser effect—nuclear magnetic resonance spectroscopy (NOE-NMR) due to unconstrained rotation of the single carbon bond between C-4 and C-5. Consequently, the relative configuration of GYMs and SPXs at C-4 and its role in protein binding remains elusive. Here, we determined the stereochemical configuration at carbon C-4 in the butenolide ring of spirolide- and gymnodimine-phycotoxins by comparison of measured 13C NMR shifts with values obtained in silico using force field, semiempirical and density functional theory methods. This comparison demonstrated that modeled data support S configuration at C-4 for all studied SPXs and GYMs, suggesting a biosynthetically conserved relative configuration at carbon C-4 among these toxins. Full article
(This article belongs to the Special Issue Isolation and Characterization of Marine Toxins)
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17 pages, 1081 KiB  
Article
Multi-Toxin Quantitative Analysis of Paralytic Shellfish Toxins and Tetrodotoxins in Bivalve Mollusks with Ultra-Performance Hydrophilic Interaction LC-MS/MS—An In-House Validation Study
by Fadillah Putri Patria, Heidi Pekar and Aida Zuberovic-Muratovic
Toxins 2020, 12(7), 452; https://doi.org/10.3390/toxins12070452 - 13 Jul 2020
Cited by 15 | Viewed by 3245
Abstract
Ultra-performance hydrophilic interaction liquid chromatography tandem mass spectrometry system (UP-HILIC–MS/MS) was used in multi-toxin analysis of paralytic shellfish toxins (PSTs) and tetrodotoxins (TTXs) in sample matrices from bivalve molluscan species commercially produced for human consumption in Sweden. The method validation includes 17 toxins [...] Read more.
Ultra-performance hydrophilic interaction liquid chromatography tandem mass spectrometry system (UP-HILIC–MS/MS) was used in multi-toxin analysis of paralytic shellfish toxins (PSTs) and tetrodotoxins (TTXs) in sample matrices from bivalve molluscan species commercially produced for human consumption in Sweden. The method validation includes 17 toxins of which GTX6 and two TTX analogues, TTX and 4,9-anhydroTTX, were previously not analyzed together with hydrophilic PSTs. 11-deoxyTTX was monitored qualitatively with a non-certified reference standard. The performance of the method was evaluated for selectivity, repeatability, and linearity by analyzing spiked samples which generated linear calibration curves across the concentration ranges used (R2 > 0.99). The in-house reproducibility (RSD) was satisfactory including the LOD and LOQ for both PST and TTX toxins being far below their regulatory action limits. The major advantage of the method is that it allows direct confirmation of the toxin identity and specific toxin quantification using a derivatization-free approach. Unlike the PST-chemical methods used in routine regulatory monitoring until now for food control, the UP-HILIC-MS/MS approach enables the calibration set-up for each of the toxin analogs separately, thereby providing the essential flexibility and specificity in analysis of this challenging group of toxins. The method is suitable to implement in food monitoring for PSTs and TTXs in bivalves, and can serve as a fast and cost-efficient screening method. However, positive samples would, for regulatory reasons still need to be confirmed using the AOAC official method (2005.06). Full article
(This article belongs to the Special Issue Isolation and Characterization of Marine Toxins)
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14 pages, 3385 KiB  
Article
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
by Seung Ho Baek, Jung Min Choi, Minji Lee, Bum Soo Park, Yuchengmin Zhang, Osamu Arakawa, Tomohiro Takatani, Joong-Kyun Jeon and Young Ok Kim
Toxins 2020, 12(7), 442; https://doi.org/10.3390/toxins12070442 - 07 Jul 2020
Cited by 11 | Viewed by 3496
Abstract
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 [...] Read more.
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). Full article
(This article belongs to the Special Issue Isolation and Characterization of Marine Toxins)
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13 pages, 2670 KiB  
Article
Co-Occurrence of Tetrodotoxin and Saxitoxins and Their Intra-Body Distribution in the Pufferfish Canthigaster valentini
by Hongchen Zhu, Takayuki Sonoyama, Misako Yamada, Wei Gao, Ryohei Tatsuno, Tomohiro Takatani and Osamu Arakawa
Toxins 2020, 12(7), 436; https://doi.org/10.3390/toxins12070436 - 03 Jul 2020
Cited by 13 | Viewed by 3686
Abstract
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 [...] Read more.
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. Full article
(This article belongs to the Special Issue Isolation and Characterization of Marine Toxins)
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12 pages, 2364 KiB  
Article
Algicidal Molecular Mechanism and Toxicological Degradation of Microcystis aeruginosa by White-Rot Fungi
by Guoming Zeng, Pei Gao, Jiale Wang, Jinxi Zhang, Maolan Zhang and Da Sun
Toxins 2020, 12(6), 406; https://doi.org/10.3390/toxins12060406 - 19 Jun 2020
Cited by 15 | Viewed by 2711
Abstract
Current research on the inhibition of Microcystis aeruginosa growth is primarily focused on algae-lysing bacteria, and few studies have investigated the inhibitory mechanisms by which fungi affect it at the molecular level. A comparative analysis of the effects of Phanerochaete chrysosporium on the [...] Read more.
Current research on the inhibition of Microcystis aeruginosa growth is primarily focused on algae-lysing bacteria, and few studies have investigated the inhibitory mechanisms by which fungi affect it at the molecular level. A comparative analysis of the effects of Phanerochaete chrysosporium on the expression of the algal cell antioxidant protease synthesis gene prx, the biological macromolecule damage and repair genes recA, grpE, and fabZ, and the photosynthesis system-related genes psaB, psbD1 and rbcL, as well as genes for algal toxin synthesis mcyB, were performed to elucidate the molecular mechanism of Phanerochaete chrysosporium against Microcystis aeruginosa cells. RT-qPCR technology was used to study the molecular mechanism of algal cell inhibition by Phanerochaete chrysosporium liquid containing metabolites of Phanerochaete chrysosporium, Phanerochaete chrysosporium supernatant and Phanerochaete chrysosporium inactivated via high temperature sterilization at the gene expression level. Compared with the control, the chlorophyll-a contents dropped, and the recA, grpE, fabZ, and prx increased, but the psaB, psbD1, rbcL and mcyB showed that they were significantly reduced, which indicated that Phanerochaete chrysosporium can not only effectively destroy algal cells, but they may also reduce the expression of the Microcystis aeruginosa toxin gene and significantly block the metabolic system underlying the growth of algal cells and the synthesis of microcystins. Full article
(This article belongs to the Special Issue Isolation and Characterization of Marine Toxins)
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11 pages, 828 KiB  
Article
Contrasting Toxin Selectivity between the Marine Pufferfish Takifugu pardalis and the Freshwater Pufferfish Pao suvattii
by Wei Gao, Yoko Kanahara, Misako Yamada, Ryohei Tatsuno, Hiroyuki Yoshikawa, Hiroyuki Doi, Tomohiro Takatani and Osamu Arakawa
Toxins 2019, 11(8), 470; https://doi.org/10.3390/toxins11080470 - 10 Aug 2019
Cited by 24 | Viewed by 3926
Abstract
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 [...] Read more.
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. Full article
(This article belongs to the Special Issue Isolation and Characterization of Marine Toxins)
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8 pages, 1943 KiB  
Article
Toxic Flatworm Egg Plates Serve as a Possible Source of Tetrodotoxin for Pufferfish
by Taiki Okabe, Hikaru Oyama, Maho Kashitani, Yuta Ishimaru, Rei Suo, Haruo Sugita and Shiro Itoi
Toxins 2019, 11(7), 402; https://doi.org/10.3390/toxins11070402 - 11 Jul 2019
Cited by 25 | Viewed by 9263
Abstract
The pufferfish Takifugu niphobles (at present Takifugu alboplumbeus) possesses highly concentrated tetrodotoxin (TTX), an extremely potent neurotoxin that provides effective protection from predators, at least at the larval stages. However, the source of the toxin has remained unclear. Recently, DNA from the [...] Read more.
The pufferfish Takifugu niphobles (at present Takifugu alboplumbeus) possesses highly concentrated tetrodotoxin (TTX), an extremely potent neurotoxin that provides effective protection from predators, at least at the larval stages. However, the source of the toxin has remained unclear. Recently, DNA from the toxic flatworm Planocera multitentaculata was detected in the intestinal contents of juveniles and young of the pufferfish, suggesting that the flatworm contributes to its toxification at various stages of its life. In this study, we describe the behavior of the pufferfish in the intertidal zone that appears to contribute to its toxification before and during its spawning period: pufferfish were found to aggregate and ingest flatworm egg plates by scraping them off the surface of rocks. DNA analysis based on 28S rRNA and cytochrome c oxidase subunit I (COI) genes identified the egg plates as those of P. multitentaculata. Liquid chromatography with tandem mass spectrometry analysis revealed that the egg plates contain highly concentrated TTX. The feeding behavior of the pufferfish on the flatworm egg plates was also observed in the aquarium. These results suggest that pufferfish feed on the flatworm egg plate, which enables them to acquire toxicity themselves while providing their offspring with the protective shield of TTX. Full article
(This article belongs to the Special Issue Isolation and Characterization of Marine Toxins)
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