1
|
Ozawa M, Uchida H, Watanabe R, Matsushima R, Oikawa H, Takahashi K, Iwataki M, Suzuki T. Azaspiracid accumulation in Japanese coastal bivalves and ascidians fed with Azadinium poporum producing azaspiracid-2 as the dominant toxin component. Toxicon 2023; 226:107069. [PMID: 36871920 DOI: 10.1016/j.toxicon.2023.107069] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2022] [Revised: 02/27/2023] [Accepted: 02/27/2023] [Indexed: 03/06/2023]
Abstract
The filter-feeding bivalves often accumulate marine toxins by feeding on toxic dinoflagellates that produce marine toxins. Azaspiracids (AZAs) are a group of lipophilic polyether toxins which have been detected in a variety of organisms in many countries. In our present study, accumulation kinetics and toxin distributions in the tissues of seven bivalve species and ascidians relevant to Japanese coastal waters were investigated by experimentally feeding a toxic dinoflagellate Azadinium poporum, which produces azaspiracid-2 (AZA2) as the dominant toxin component. All bivalve species and ascidians investigated in this study had the capability to accumulate AZA2 and no metabolites of AZA2 were detected in the bivalves and the ascidians. Japanese short-neck clams, Japanese oysters, Pacific oysters and ascidians accumulated AZA2 with the highest concentrations on the hepatopancreas, whereas the highest concentrations of AZA2 were found on the gills in surf clams and horse clams. Hard clams and cockles accumulated high levels of AZA2 in both the hepatopancreas and the gills. As far as we know, this is the first report describing detailed tissue distribution of AZAs in several bivalve species other than mussels (M. edulis) and scallops (P. maximus). Variation of accumulation rates of AZA2 in Japanese short-neck clams on different cell densities or temperatures were observed.
Collapse
Affiliation(s)
- Mayu Ozawa
- Tokyo University of Marine Science and Technology, 4-5-7 Konan, Minato, Tokyo, 108-8477, Japan; Fisheries Technology Institute, Japan Fisheries Research and Education Agency, 2-12-4 Fukuura, Kanazawa, Yokohama, Kanagawa, 236-8648, Japan.
| | - Hajime Uchida
- Fisheries Technology Institute, Japan Fisheries Research and Education Agency, 2-12-4 Fukuura, Kanazawa, Yokohama, Kanagawa, 236-8648, Japan.
| | - Ryuichi Watanabe
- Fisheries Technology Institute, Japan Fisheries Research and Education Agency, 2-12-4 Fukuura, Kanazawa, Yokohama, Kanagawa, 236-8648, Japan.
| | - Ryoji Matsushima
- Fisheries Technology Institute, Japan Fisheries Research and Education Agency, 2-12-4 Fukuura, Kanazawa, Yokohama, Kanagawa, 236-8648, Japan.
| | - Hiroshi Oikawa
- Fisheries Technology Institute, Japan Fisheries Research and Education Agency, 2-12-4 Fukuura, Kanazawa, Yokohama, Kanagawa, 236-8648, Japan.
| | - Kazuya Takahashi
- Graduate School of Agricultural and Life Sciences, The University of Tokyo, 1-1-1 Yayoi, Bunkyo, Tokyo, 113-8657, Japan.
| | - Mitsunori Iwataki
- Graduate School of Agricultural and Life Sciences, The University of Tokyo, 1-1-1 Yayoi, Bunkyo, Tokyo, 113-8657, Japan.
| | - Toshiyuki Suzuki
- Fisheries Technology Institute, Japan Fisheries Research and Education Agency, 2-12-4 Fukuura, Kanazawa, Yokohama, Kanagawa, 236-8648, Japan.
| |
Collapse
|
2
|
Neves RAF, Nascimento SM, Santos LN. Harmful algal blooms and shellfish in the marine environment: an overview of the main molluscan responses, toxin dynamics, and risks for human health. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2021; 28:55846-55868. [PMID: 34480308 DOI: 10.1007/s11356-021-16256-5] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/24/2021] [Accepted: 08/26/2021] [Indexed: 06/13/2023]
Abstract
Besides human health risks, phycotoxins may cause physiological injuries on molluscan shellfish and, consequently, damages to marine ecosystems and global fisheries production. In this way, this review aimed to present an overview of HABs impacts on marine shellfish by evaluating the effects of cultivated molluscs exposure to microalgae and cyanobacteria that form blooms and/or synthesize toxins. More specifically, it was assessed the main molluscan shellfish responses to harmful algae, trophic transfer and dynamics of phycotoxins, and the risks for human health. Of the 2420 results obtained from literature search, 150 scientific publications were selected after thorough inspections for subject adherence. In total, 70 molluscan species and 37 taxa of harmful algae were assessed from retrieved scientific publications. A significant positive correlation was found between the marine production of molluscs and the number of available studies by molluscan category. Molluscan responses to HABs and phycotoxins were categorized and discussed in three sub-sections: effects on grazing and behavior, metabolic and physiological reactions, and fitness consequences. The main histopathological injuries and toxin concentrations in molluscan tissues were also compiled and discussed. Bivalves often accumulate more toxins than gastropods and cephalopods, occasionally exceeding recommended levels for safe consumption, representing a risk for human health. Harmful algae impact on molluscan shellfish are complex to trace and predict; however, considering the perspective of increase in the occurrence and intensity of HABs, the intensification of efforts to expand the knowledge about HABs impacts on marine molluscs is crucial to mitigate the damages on economy and human health.
Collapse
Affiliation(s)
- Raquel A F Neves
- Graduate Program in Neotropical Biodiversity, Institute of Biosciences, Federal University of the State of Rio de Janeiro (UNIRIO), Avenida Pasteur, 458, Urca, Rio de Janeiro, CEP: 22.290-240, Brazil.
- Research Group of Experimental and Applied Aquatic Ecology, Institute of Biosciences, Federal University of the State of Rio de Janeiro (UNIRIO), Avenida Pasteur, 458 - 307, Urca, Rio de Janeiro, CEP: 22.290-240, Brazil.
| | - Silvia M Nascimento
- Graduate Program in Neotropical Biodiversity, Institute of Biosciences, Federal University of the State of Rio de Janeiro (UNIRIO), Avenida Pasteur, 458, Urca, Rio de Janeiro, CEP: 22.290-240, Brazil
- Laboratory of Marine Microalgae, Institute of Biosciences, Federal University of the State of Rio de Janeiro (UNIRIO), Avenida Pasteur, 458 - 314A, Urca, Rio de Janeiro, CEP: 22.290-240, Brazil
| | - Luciano N Santos
- Graduate Program in Neotropical Biodiversity, Institute of Biosciences, Federal University of the State of Rio de Janeiro (UNIRIO), Avenida Pasteur, 458, Urca, Rio de Janeiro, CEP: 22.290-240, Brazil
- Laboratory of Theoretical and Applied Ichthyology, Institute of Biosciences, Federal University of the State of Rio de Janeiro (UNIRIO), Avenida Pasteur, 458 - 314A, Urca, Rio de Janeiro, CEP: 22.290-240, Brazil
| |
Collapse
|
3
|
Mudge EM, Miles CO, Hardstaff WR, McCarron P. Fatty acid esters of azaspiracids identified in mussels ( Mytilus edulis) using liquid chromatography-high resolution mass spectrometry. Toxicon X 2020; 8:100059. [PMID: 33073234 PMCID: PMC7549145 DOI: 10.1016/j.toxcx.2020.100059] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2020] [Revised: 08/25/2020] [Accepted: 09/25/2020] [Indexed: 12/02/2022] Open
Abstract
Azaspiracids (AZAs) are lipophilic polyether toxins produced by Azadinium and Amphidoma species of marine microalgae. The main dinoflagellate precursors AZA1 and AZA2 are metabolized by shellfish to produce an array of AZA analogues. Many marine toxins undergo fatty acid esterification in shellfish, therefore mussel tissues contaminated with AZAs were screened for intact fatty acid esters of AZAs using liquid chromatography-high resolution mass spectrometry. Acyl esters were primarily observed for AZAs containing hydroxy groups at C-3 with 3-O-palmitoylAZA4 identified as the most abundant acyl ester, while other fatty acid esters including 18:1, 16:1, 17:0, 20:2 and 18:0 acyl esters were detected. The structures of these acyl derivatives were determined through LC-MS/MS experiments, and supported by periodate cleavage reactions and semi-synthesis of palmitate esters of the AZAs. Esters of the hydroxy groups at C-20 or C-21 were not observed in mussel tissue. The relative proportion of the most abundant AZA ester was less than 3% of the sum of the major free AZA analogues. These findings reveal an additional metabolic pathway for AZAs in shellfish. Fatty acid esters of azaspiracids were identified in mussels (Mytilus edulis). Fatty acid esters of azaspiracids with hydroxy groups at C-3 were primarily observed. Fatty acid esters of regulated azaspiracids (AZA1, 2, −3) were absent. Structures were determined with LC-HRMS and confirmed by semi-synthesis of palmitate esters and periodate cleavage. This work reveals an additional metabolic pathway for azaspiracids in shellfish.
Collapse
|
4
|
Lassudrie M, Hégaret H, Wikfors GH, da Silva PM. Effects of marine harmful algal blooms on bivalve cellular immunity and infectious diseases: A review. DEVELOPMENTAL AND COMPARATIVE IMMUNOLOGY 2020; 108:103660. [PMID: 32145294 DOI: 10.1016/j.dci.2020.103660] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/09/2019] [Revised: 02/04/2020] [Accepted: 02/18/2020] [Indexed: 06/10/2023]
Abstract
Bivalves were long thought to be "symptomless carriers" of marine microalgal toxins to human seafood consumers. In the past three decades, science has come to recognize that harmful algae and their toxins can be harmful to grazers, including bivalves. Indeed, studies have shown conclusively that some microalgal toxins function as active grazing deterrents. When responding to marine Harmful Algal Bloom (HAB) events, bivalves can reject toxic cells to minimize toxin and bioactive extracellular compound (BEC) exposure, or ingest and digest cells, incorporating nutritional components and toxins. Several studies have reported modulation of bivalve hemocyte variables in response to HAB exposure. Hemocytes are specialized cells involved in many functions in bivalves, particularly in immunological defense mechanisms. Hemocytes protect tissues by engulfing or encapsulating living pathogens and repair tissue damage caused by injury, poisoning, and infections through inflammatory processes. The effects of HAB exposure observed on bivalve cellular immune variables have raised the question of possible effects on susceptibility to infectious disease. As science has described a previously unrecognized diversity in microalgal bioactive substances, and also found a growing list of infectious diseases in bivalves, episodic reports of interactions between harmful algae and disease in bivalves have been published. Only recently, studies directed to understand the physiological and metabolic bases of these interactions have been undertaken. This review compiles evidence from studies of harmful algal effects upon bivalve shellfish that establishes a framework for recent efforts to understand how harmful algae can alter infectious disease, and particularly the fundamental role of cellular immunity, in modulating these interactions. Experimental studies reviewed here indicate that HABs can modulate bivalve-pathogen interactions in various ways, either by increasing bivalve susceptibility to disease or conversely by lessening infection proliferation or transmission. Alteration of immune defense and global physiological distress caused by HAB exposure have been the most frequent reasons identified for these effects on disease. Only few studies, however, have addressed these effects so far and a general pattern cannot be established. Other mechanisms are likely involved but are under-studied thus far and will need more attention in the future. In particular, the inhibition of bivalve filtration by HABs and direct interaction between HABs and infectious agents in the seawater likely interfere with pathogen transmission. The study of these interactions in the field and at the population level also are needed to establish the ecological and economical significance of the effects of HABs upon bivalve diseases. A more thorough understanding of these interactions will assist in development of more effective management of bivalve shellfisheries and aquaculture in oceans subjected to increasing HAB and disease pressures.
Collapse
Affiliation(s)
| | - Hélène Hégaret
- CNRS, Univ Brest, IRD, Ifremer, LEMAR, F-29280, Plouzané, France
| | - Gary H Wikfors
- NOAA Fisheries Service, Northeast Fisheries Science Center, Milford, CT, 0640, USA
| | - Patricia Mirella da Silva
- Laboratory of Immunology and Pathology of Invertebrates, Department of Molecular Biology, Federal University of Paraíba (UFPB), Paraíba, Brazil
| |
Collapse
|
5
|
Biological Effects of the Azaspiracid-Producing Dinoflagellate Azadinium dexteroporum in Mytilus galloprovincialis from the Mediterranean Sea. Mar Drugs 2019; 17:md17100595. [PMID: 31652521 PMCID: PMC6835248 DOI: 10.3390/md17100595] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2019] [Revised: 10/17/2019] [Accepted: 10/18/2019] [Indexed: 12/11/2022] Open
Abstract
Azaspiracids (AZAs) are marine biotoxins including a variety of analogues. Recently, novel AZAs produced by the Mediterranean dinoflagellate Azadinium dexteroporum were discovered (AZA-54, AZA-55, 3-epi-AZA-7, AZA-56, AZA-57 and AZA-58) and their biological effects have not been investigated yet. This study aimed to identify the biological responses (biomarkers) induced in mussels Mytilus galloprovincialis after the bioaccumulation of AZAs from A. dexteroporum. Organisms were fed with A. dexteroporum for 21 days and subsequently subjected to a recovery period (normal diet) of 21 days. Exposed organisms accumulated AZA-54, 3-epi-AZA-7 and AZA-55, predominantly in the digestive gland. Mussels' haemocytes showed inhibition of phagocytosis activity, modulation of the composition of haemocytic subpopulation and damage to lysosomal membranes; the digestive tissue displayed thinned tubule walls, consumption of storage lipids and accumulation of lipofuscin. Slight genotoxic damage was also observed. No clear occurrence of oxidative stress and alteration of nervous activity was detected in AZA-accumulating mussels. Most of the altered parameters returned to control levels after the recovery phase. The toxic effects detected in M. galloprovincialis demonstrate a clear biological impact of the AZAs produced by A. dexteroporum, and could be used as early indicators of contamination associated with the ingestion of seafood.
Collapse
|
6
|
Brown ER, Cepeda MR, Mascuch SJ, Poulson-Ellestad KL, Kubanek J. Chemical ecology of the marine plankton. Nat Prod Rep 2019; 36:1093-1116. [DOI: 10.1039/c8np00085a] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
A review of chemically mediated interactions in planktonic marine environments covering new studies from January 2015 to December 2017.
Collapse
Affiliation(s)
- Emily R. Brown
- School of Biological Sciences
- Aquatic Chemical Ecology Center
- Institute for Bioengineering and Biosciences
- Georgia Institute of Technology
- Atlanta
| | - Marisa R. Cepeda
- School of Chemistry and Biochemistry
- Aquatic Chemical Ecology Center
- Institute for Bioengineering and Biosciences
- Georgia Institute of Technology
- Atlanta
| | - Samantha J. Mascuch
- School of Biological Sciences
- Aquatic Chemical Ecology Center
- Institute for Bioengineering and Biosciences
- Georgia Institute of Technology
- Atlanta
| | | | - Julia Kubanek
- School of Biological Sciences
- Aquatic Chemical Ecology Center
- Institute for Bioengineering and Biosciences
- Georgia Institute of Technology
- Atlanta
| |
Collapse
|
7
|
Effect of Suspended Particulate Matter on the Accumulation of Dissolved Diarrhetic Shellfish Toxins by Mussels ( Mytilus galloprovincialis) under Laboratory Conditions. Toxins (Basel) 2018; 10:toxins10070273. [PMID: 29970810 PMCID: PMC6071173 DOI: 10.3390/toxins10070273] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2018] [Revised: 06/19/2018] [Accepted: 06/28/2018] [Indexed: 11/17/2022] Open
Abstract
In recent years, detection of trace amounts of dissolved lipophilic phycotoxins in coastal waters has been possible using solid phase adsorption toxin tracking (SPATT) samplers. To explore the contribution of dissolved diarrhetic shellfish toxins (DST) to the accumulation of toxins by cultivated bivalves, mussels (Mytilus galloprovincialis) were exposed to different concentrations of purified okadaic acid (OA) and dinophysistoxin-1 (DTX1) in filtered (0.45 µm) seawater for 96 h. Accumulation and esterification of DST by mussels under different experimental conditions, including with and without the addition of the food microalga Isochrysis galbana, and with the addition of different size-fractions of suspended particulate matter (SPM) (<75 µm, 75–150 µm, 150–250 µm) were compared. Results showed that mussels accumulated similar amounts of OA and DTX1 from seawater with or without food microalgae present, and slightly lower amounts when SPM particles were added. Mussels preferentially accumulated OA over DTX1 in all treatments. The efficiency of the mussel’s accumulation of OA and DTX1 from seawater spiked with low concentrations of toxins was higher than that in seawater with high toxin levels. A large proportion of OA (86–94%) and DTX1 (65–82%) was esterified to DTX3 by mussels in all treatments. The proportion of I. galbana cells cleared by mussels was markedly inhibited by dissolved OA and DTX1 (OA 9.2 µg L−1, DTX1 13.2 µg L−1) in seawater. Distribution of total OA and DTX1 accumulated in the mussel tissues ranked in all treatments as follows: digestive gland > gills > mantle > residual tissues. However, the percentage of total DST in the digestive gland of mussels in filtered seawater (67%) was higher than with the addition of SPM particles (75–150 µm) (51%), whereas the gills showed the opposite trend in filtered seawater with (27%) and without (14.4%) SPM particles. Results presented here will improve our understanding of the mechanisms of DST accumulation by bivalves in marine aquaculture environments.
Collapse
|
8
|
Roué M, Darius HT, Chinain M. Solid Phase Adsorption Toxin Tracking (SPATT) Technology for the Monitoring of Aquatic Toxins: A Review. Toxins (Basel) 2018; 10:toxins10040167. [PMID: 29677131 PMCID: PMC5923333 DOI: 10.3390/toxins10040167] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2018] [Revised: 04/17/2018] [Accepted: 04/18/2018] [Indexed: 12/26/2022] Open
Abstract
The Solid Phase Adsorption Toxin Tracking (SPATT) technology, first introduced in 2004, uses porous synthetic resins capable of passively adsorbing toxins produced by harmful microalgae or cyanobacteria and dissolved in the water. This method allows for the detection of toxic compounds directly in the water column and offers numerous advantages over current monitoring techniques (e.g., shellfish or fish testing and microalgae/cyanobacteria cell detection), despite some limitations. Numerous laboratory and field studies, testing different adsorbent substrates of which Diaion® HP20 resin appears to be the most versatile substrate, have been carried out worldwide to assess the applicability of these passive monitoring devices to the detection of toxins produced by a variety of marine and freshwater microorganisms. SPATT technology has been shown to provide reliable, sensitive and time-integrated sampling of various aquatic toxins, and also has the potential to provide an early warning system for both the occurrence of toxic microalgae or cyanobacteria and bioaccumulation of toxins in foodstuffs. This review describes the wide range of lipophilic and hydrophilic toxins associated with toxin-producing harmful algal blooms (HABs) that are successfully detected by SPATT devices. Implications in terms of monitoring of emerging toxic risks and reinforcement of current risk assessment programs are also discussed.
Collapse
Affiliation(s)
- Mélanie Roué
- Institut de Recherche pour le Développement (IRD), UMR 241 EIO, P.O. box 53267, 98716 Pirae, Tahiti, French Polynesia.
| | - Hélène Taiana Darius
- Laboratory of Toxic Microalgae, Institut Louis Malardé (ILM), UMR 241 EIO, P.O. box 30, 98713 Papeete, Tahiti, French Polynesia.
| | - Mireille Chinain
- Laboratory of Toxic Microalgae, Institut Louis Malardé (ILM), UMR 241 EIO, P.O. box 30, 98713 Papeete, Tahiti, French Polynesia.
| |
Collapse
|
9
|
Ji Y, Qiu J, Xie T, McCarron P, Li A. Accumulation and transformation of azaspiracids in scallops (Chlamys farreri) and mussels (Mytilus galloprovincialis) fed with Azadinium poporum, and response of antioxidant enzymes. Toxicon 2017; 143:20-28. [PMID: 29229237 DOI: 10.1016/j.toxicon.2017.12.040] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2017] [Revised: 12/02/2017] [Accepted: 12/06/2017] [Indexed: 11/16/2022]
Abstract
Azaspiracid (AZA) producing microalgae have been reported internationally and could potentially impact a variety of seafood. Scallops (Chlamys farreri) and mussels (Mytilus galloprovincialis) from China were fed with the AZA2 producer, Azadinium poporum, to study uptake, metabolism and oxidative stress in the shellfish. LC-MS/MS showed significant accumulation and differential metabolism of AZA2 in the scallops and mussels. In mussels AZA2 was metabolized to AZA19, with subsequent decarboxylation to AZA6. In scallops no AZA19 or AZA6 was observed, however, a novel AZA metabolite was formed that is isobaric with AZA19 ([M+H]+, m/z 886), but elutes at a different retention time. In addition it was noted that the scallop metabolite was stable during heating, while AZA19 has been shown to decarboxylate. Concentrations of reactive oxygen species (ROS) and activities of antioxidant enzymes were monitored. ROS levels increased slightly in the meat of scallops and mussels due to starvation in the acclimation and depuration periods, but reduced in the feeding periods with non-toxic Isochrysis galbana or toxic A. poporum. No obvious variations were found in activities for a range of antioxidant enzymes. These results provide new insights on the potential for accumulation and metabolism of AZAs in bivalve species relevant to this area of China, which is of importance considering the recent finding of AZA producing microalgae in the region.
Collapse
Affiliation(s)
- Ying Ji
- College of Environmental Science and Engineering, Ocean University of China, Qingdao, 266100, China; Key Laboratory of Marine Environment and Ecology, Ocean University of China, Ministry of Education, Qingdao, 266100, China
| | - Jiangbing Qiu
- College of Environmental Science and Engineering, Ocean University of China, Qingdao, 266100, China; Key Laboratory of Marine Environment and Ecology, Ocean University of China, Ministry of Education, Qingdao, 266100, China
| | - Tian Xie
- College of Environmental Science and Engineering, Ocean University of China, Qingdao, 266100, China
| | - Pearse McCarron
- Measurement Science and Standards, National Research Council Canada, 1411 Oxford Street, Halifax, B3H 3Z1, Nova Scotia, Canada
| | - Aifeng Li
- College of Environmental Science and Engineering, Ocean University of China, Qingdao, 266100, China; Key Laboratory of Marine Environment and Ecology, Ocean University of China, Ministry of Education, Qingdao, 266100, China.
| |
Collapse
|
10
|
Nielsen LT, Hansen PJ, Krock B, Vismann B. Accumulation, transformation and breakdown of DSP toxins from the toxic dinoflagellate Dinophysis acuta in blue mussels, Mytilus edulis. Toxicon 2016; 117:84-93. [PMID: 27045361 DOI: 10.1016/j.toxicon.2016.03.021] [Citation(s) in RCA: 42] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2016] [Revised: 03/08/2016] [Accepted: 03/31/2016] [Indexed: 11/24/2022]
Abstract
Okadaic acid (OA), dinophysistoxins (DTX) and pectenotoxins (PTX) produced by the dinoflagellates Dinophysis spp. can accumulate in shellfish and cause diarrhetic shellfish poisoning upon human consumption. Shellfish toxicity is a result of algal abundance and toxicity as well as accumulation and depuration kinetics in mussels. We mass-cultured Dinophysis acuta containing OA, DTX-1b and PTX-2 and fed it to the blue mussel, Mytilus edulis under controlled laboratory conditions for a week to study toxin accumulation and transformation. Contents of OA and DTX-1b in mussels increased linearly with incubation time, and the net toxin accumulation was 66% and 71% for OA and DTX-1b, respectively. Large proportions (≈50%) of both these toxins were transformed to fatty acid esters. Most PTX-2 was transformed to PTX-2 seco-acid and net accumulation was initially high, but decreased progressively throughout the experiment, likely due to esterification and loss of detectability. We also quantified depuration during the subsequent four days and found half-life times of 5-6 days for OA and DTX-1b. Measurements of dissolved toxins revealed that depuration was achieved through excreting rather than metabolizing toxins. This is the first study to construct a full mass balance of DSP toxins during both accumulation and depuration, and we demonstrate rapid toxin accumulation in mussels at realistic in situ levels of Dinophysis. Applying the observed accumulation and depuration kinetics, we model mussel toxicity, and demonstrate that a concentration of only 75 Dinophysis cells l(-1) is enough to make 60 mm long mussels exceed the regulatory threshold for OA equivalents.
Collapse
Affiliation(s)
- Lasse Tor Nielsen
- Centre for Ocean Life, National Institute of Aquatic Resources, Technical University of Denmark, DK-2920 Charlottenlund, Denmark.
| | - Per Juel Hansen
- Marine Biological Section, University of Copenhagen, Strandpromenaden 5, DK-3000 Helsingør, Denmark
| | - Bernd Krock
- Alfred-Wegener-Institute for Polar and Marine Research, Am Handelshafen 12, D-27570 Bremerhaven, Germany
| | - Bent Vismann
- Marine Biological Section, University of Copenhagen, Strandpromenaden 5, DK-3000 Helsingør, Denmark
| |
Collapse
|
11
|
Everaert G, De Laender F, Goethals PLM, Janssen CR. Multidecadal Field Data Support Intimate Links between Phytoplankton Dynamics and PCB Concentrations in Marine Sediments and Biota. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2015; 49:8704-8711. [PMID: 26079074 DOI: 10.1021/acs.est.5b01159] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
We analyzed three decades of field observations in the North Sea with additive models to infer spatiotemporal trends of chlorophyll a concentration, sediment organic carbon content, and polychlorinated biphenyls (PCBs) concentrations in mussels and sediments. By doing so, we separated long-term changes in PCB concentrations from seasonal variability. Using the inferred seasonal variability, we demonstrated that phytoplankton blooms in spring and autumn correspond to the annual maxima of the organic carbon content (r = 0.56; p = 0.004) and the PCB concentrations in sediments (r = 0.57; p = 0.004). Furthermore, we found a negative correlation between the PCB concentrations in sediments and in blue mussels (Mytilus edulis; r = -0.33, p = 0.012), which is probably related to the cleansing of the dissolved PCB phase driven by sinking organic matter during phytoplankton blooms and the filter-feeding behavior of the blue mussel. The present research demonstrates the role of seasonal phytoplankton dynamics in the environmental fate of PCBs at large spatiotemporal scales.
Collapse
Affiliation(s)
- Gert Everaert
- †Ghent University, Laboratory of Environmental Toxicology and Aquatic Ecology, J. Plateaustraat 22, B-9000 Ghent, Belgium
| | - Frederik De Laender
- ‡Université de Namur, Research Unit in Environmental and Evolutionary Biology, Laboratory of Environmental Ecosystem Ecology, Rue de Bruxelles 61, B-5000 Namur, Belgium
| | - Peter L M Goethals
- †Ghent University, Laboratory of Environmental Toxicology and Aquatic Ecology, J. Plateaustraat 22, B-9000 Ghent, Belgium
| | - Colin R Janssen
- †Ghent University, Laboratory of Environmental Toxicology and Aquatic Ecology, J. Plateaustraat 22, B-9000 Ghent, Belgium
| |
Collapse
|
12
|
Kilcoyne J, Nulty C, Jauffrais T, McCarron P, Herve F, Foley B, Rise F, Crain S, Wilkins AL, Twiner MJ, Hess P, Miles CO. Isolation, structure elucidation, relative LC-MS response, and in vitro toxicity of azaspiracids from the dinoflagellate Azadinium spinosum. JOURNAL OF NATURAL PRODUCTS 2014; 77:2465-2474. [PMID: 25356854 DOI: 10.1021/np500555k] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
We identified three new azaspiracids (AZAs) with molecular weights of 715, 815, and 829 (AZA33 (3), AZA34 (4), and AZA35, respectively) in mussels, seawater, and Azadinium spinosum culture. Approximately 700 μg of 3 and 250 μg of 4 were isolated from a bulk culture of A. spinosum, and their structures determined by MS and NMR spectroscopy. These compounds differ significantly at the carboxyl end of the molecule from known AZA analogues and therefore provide valuable information on structure-activity relationships. Initial toxicological assessment was performed using an in vitro model system based on Jurkat T lymphocyte cytotoxicity, and the potencies of 3 and 4 were found to be 0.22- and 5.5-fold that of AZA1 (1), respectively. Thus, major changes in the carboxyl end of 1 resulted in significant changes in toxicity. In mussel extracts, 3 was detected at low levels, whereas 4 and AZA35 were detected only at extremely low levels or not at all. The structures of 3 and 4 are consistent with AZAs being biosynthetically assembled from the amino end.
Collapse
Affiliation(s)
- Jane Kilcoyne
- Marine Institute , Rinville, Oranmore, Galway, Ireland
| | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|