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Ozawa M, Uchida H, Watanabe R, Numano S, Matsushima R, Oikawa H, Takahashi K, Lum WM, Benico G, Iwataki M, Suzuki T. New azaspiracid analogues detected as bi-charged ions in Azadinium poporum (Amphidomataceae, Dinophyceae) isolated from Japanese coastal waters. J Chromatogr B Analyt Technol Biomed Life Sci 2024; 1236:124065. [PMID: 38460449 DOI: 10.1016/j.jchromb.2024.124065] [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: 09/22/2023] [Revised: 01/22/2024] [Accepted: 02/20/2024] [Indexed: 03/11/2024]
Abstract
Lipophilic marine biotoxin azaspiracids (AZAs) are produced by dinoflagellates Azadinium and Amphidoma. Recently, several strains of Azadinium poporum were isolated from Japanese coastal waters, and detailed toxin profiles of two strains (mdd421 and HM536) among them were clarified by several detection techniques on liquid chromatography-tandem mass spectrometry (LC-MS/MS) and liquid chromatography-quadrupole time of flight mass spectrometry (LC-QTOFMS). In our present study, AZA analogues in seven strains of A. poporum from Japanese coastal waters (including two previously reported strains) were determined by these detection techniques. The dominant AZA in the seven strains was AZA2 accompanied by small amounts of several known AZAs and twelve new AZA analogues. Eight of the twelve new AZA analogues discovered in our present study were detected as bi-charged ions on the positive mode LC/MS/MS. This is the first report describing AZA analogues detected as bi-charged ions with hexose and sulfate groups in their structures.
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Affiliation(s)
- Mayu Ozawa
- 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.
| | - Satoshi Numano
- 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.
| | - Wai Mun Lum
- Fisheries Technology Institute, Japan Fisheries Research and Education Agency, 2-12-4 Fukuura, Kanazawa, Yokohama, Kanagawa 236-8648, Japan; Graduate School of Agricultural and Life Sciences, The University of Tokyo, 1-1-1 Yayoi, Bunkyo, Tokyo 113-8657, Japan.
| | - Garry Benico
- Department of Biological Sciences, Central Luzon State University, Science City of Muñoz, Nueva Ecija, Philippines.
| | - 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.
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Salas R, Murphy E, Doohan R, Tillmann U, Thomas OP. Production of the dinoflagellate Amphidoma languida in a large scale photobioreactor and structure elucidation of its main metabolite AZA-39. HARMFUL ALGAE 2023; 127:102471. [PMID: 37544671 DOI: 10.1016/j.hal.2023.102471] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/08/2023] [Revised: 05/27/2023] [Accepted: 06/10/2023] [Indexed: 08/08/2023]
Abstract
Shellfish contamination with azaspiracids (AZA) is a major and recurrent problem for the Irish shellfish industry. Amphidoma languida, a small thecate dinoflagellate of the family Amphidomataceae, is widely distributed in Irish coastal waters and is one of the identified source species of azaspiracids. Irish and North Sea strains of Am. languida have been found to produce as major metabolites AZA-38 and -39 whose structures have only been provisionally elucidated by mass spectrometry and their toxic potential is currently unknown. In order to provide pure AZA-38 and -39 for subsequent structural and toxicological analyses, we present the first successful large-scale culture of Am. languida. A 180 L in house prototype bioreactor was used for culture growth and harvesting in semi-continuous mode for two months. Two different runs of the photobiorector with different light and pH setting showed the highest toxin yield at higher light intensity and slightly higher pH. AZA-38 and -39 cell quota were measured throughout the complete growth cycle with AZA-39 cell quota increasing in proportion to AZA-38 at late stationary to senescence phase. Over two experiments a total of 700 L of culture was harvested yielding 0.45 mg of pure AZA-39. The structure of AZA-39 was elucidated through NMR data analyses, which led to a revision of the structure proposed previously by mass spectrometry. While the spirotetrahydrofuran/tetrahydrofuran of rings A and B has been confirmed by NMR for AZA-39, a methyl is still present in position C-14 and the carboxylic acid chain is different from the structure proposed initially.
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Affiliation(s)
- Rafael Salas
- Marine Institute, Rinville, Oranmore, H91 R673, Co. Galway, Ireland.
| | - Elliot Murphy
- Marine Institute, Rinville, Oranmore, H91 R673, Co. Galway, Ireland; School of Biological and Chemical Sciences, Ryan Institute, University of Galway, University Road, H91TK33 Galway, Ireland
| | - Roisin Doohan
- School of Biological and Chemical Sciences, Ryan Institute, University of Galway, University Road, H91TK33 Galway, Ireland
| | - Urban Tillmann
- Alfred Wegener Institut-Helmholtz Zentrum für Polar- und Meeresforschung Am Handelshafen 12, D-27570 Bremerhaven, Germany
| | - Olivier P Thomas
- School of Biological and Chemical Sciences, Ryan Institute, University of Galway, University Road, H91TK33 Galway, Ireland
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Tebben J, Zurhelle C, Tubaro A, Samdal IA, Krock B, Kilcoyne J, Sosa S, Trainer VL, Deeds JR, Tillmann U. Structure and toxicity of AZA-59, an azaspiracid shellfish poisoning toxin produced by Azadinium poporum (Dinophyceae). HARMFUL ALGAE 2023; 124:102388. [PMID: 37164556 DOI: 10.1016/j.hal.2023.102388] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/01/2022] [Revised: 01/13/2023] [Accepted: 01/18/2023] [Indexed: 05/12/2023]
Abstract
To date, the putative shellfish toxin azaspiracid 59 (AZA-59) produced by Azadinium poporum (Dinophyceae) has been the only AZA found in isolates from the Pacific Northwest coast of the USA (Northeast Pacific Ocean). Anecdotal reports of sporadic diarrhetic shellfish poisoning-like illness, with the absence of DSP toxin or Vibrio contamination, led to efforts to look for other potential toxins, such as AZAs, in water and shellfish from the region. A. poporum was found in Puget Sound and the outer coast of Washington State, USA, and a novel AZA (putative AZA-59) was detected in low quantities in SPATT resins and shellfish. Here, an A. poporum strain from Puget Sound was mass-cultured and AZA-59 was subsequently purified and structurally characterized. In vitro cytotoxicity of AZA-59 towards Jurkat T lymphocytes and acute intraperitoneal toxicity in mice in comparison to AZA-1 allowed the derivation of a provisional toxicity equivalency factor of 0.8 for AZA-59. Quantification of AZA-59 using ELISA and LC-MS/MS yielded reasonable quantitative results when AZA-1 was used as an external reference standard. This study assesses the toxic potency of AZA-59 and will inform guidelines for its potential monitoring in case of increasing toxin levels in edible shellfish.
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Affiliation(s)
- Jan Tebben
- Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research, Section Ecological Chemistry, Am Handelshafen 12, Bremerhaven, 27570, Germany.
| | - Christian Zurhelle
- University of Bremen, Department of Biology and Chemistry, Marine Chemistry, Leobener Straße 6, Bremen, 28359, Germany
| | - Aurelia Tubaro
- Department of Life Sciences, University of Trieste, Via A. Valerio 6, Trieste, 34127, Italy
| | | | - Bernd Krock
- Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research, Section Ecological Chemistry, Am Handelshafen 12, Bremerhaven, 27570, Germany
| | - Jane Kilcoyne
- Marine Institute, Rinville, Oranmore, County Galway H91 R673, Ireland
| | - Silvio Sosa
- Department of Life Sciences, University of Trieste, Via A. Valerio 6, Trieste, 34127, Italy
| | - Vera L Trainer
- Olympic Natural Resources Center, University of Washington, 1455 S. Forks Ave, Forks, WA 98331, United States
| | - Jonathan R Deeds
- Center for Food Safety and Applied Nutrition, Office of Regulatory Science, U.S. Food and Drug Administration, 5001 Campus Drive, College Park, Maryland, 20740, United States of America
| | - Urban Tillmann
- Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research, Section Ecological Chemistry, Am Handelshafen 12, Bremerhaven, 27570, Germany.
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Preparation of Ciguatoxin Reference Materials from Canary Islands (Spain) and Madeira Archipelago (Portugal) Fish. JOURNAL OF MARINE SCIENCE AND ENGINEERING 2022. [DOI: 10.3390/jmse10060835] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Ciguatoxins (CTXs) are naturally occurring neurotoxins that can accumulate in fish and cause Ciguatera Poisoning (CP) in seafood consumers. Ciguatoxic fish have been detected in tropical and subtropical regions of the world including the Pacific and Indian Oceans, the Caribbean Sea, and more recently in the northeast Atlantic Ocean. The biogeographic distribution of ciguatoxic fish appears to be expanding; however, the paucity of CTX standards and reference materials limits the ability of public health authorities to monitor for these toxins in seafood supply chains. Recent reports establish that Caribbean Ciguatoxin-1 (C-CTX1) is the principal toxin responsible for CP cases and outbreaks in the northeast Atlantic Ocean and that C-CTX congener profiles in contaminated fish samples match those from the Caribbean Sea. Therefore, in this work, C-CTX reference materials were prepared from fish obtained from the northeast Atlantic Ocean. The collection of fish specimens (e.g., amberjack, grouper, or snapper) was screened for CTX-like toxicity using the in vitro sodium channel mouse neuroblastoma cytotoxicity assay (N2a cell assay). Muscle and liver tissues from toxic specimens were pooled for extraction and purified products were ultimately profiled and quantified by comparison with authentic C-CTX1 using LC-MS/MS. This work presents a detailed protocol for the preparation of purified C-CTX reference materials to enable continued research and monitoring of the ciguatera public health hazard. To carry out this work, C-CTX1 was isolated and purified from fish muscle and liver tissues obtained from the Canary Islands (Spain) and Madeira archipelago (Portugal).
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McGirr S, Clarke D, Kilcoyne J, Silke J, Touzet N. Co-localisation of Azaspiracid Analogs with the Dinoflagellate Species Azadinium spinosum and Amphidoma languida in the Southwest of Ireland. MICROBIAL ECOLOGY 2022; 83:635-646. [PMID: 34195856 DOI: 10.1007/s00248-021-01777-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/21/2020] [Accepted: 05/17/2021] [Indexed: 06/13/2023]
Abstract
Phytoplankton and biotoxin monitoring programmes have been implemented in many countries to protect human health and to mitigate the impacts of harmful algal blooms (HABs) on the aquaculture industry. Several amphidomatacean species have been confirmed in Irish coastal waters, including the azaspiracid-producing species Azadinium spinosum and Amphidoma languida. Biogeographic distribution studies have been hampered by the fact that these small, armoured dinoflagellates share remarkably similar morphologies when observed by light microscopy. The recent releases of species-specific molecular detection assays have, in this context, been welcome developments. A survey of the south west and west coasts of Ireland was carried out in August 2017 to investigate the late summer distribution of toxic amphidomataceans and azaspiracid toxins. Azadinium spinosum and Am. languida were detected in 83% of samples in the southwest along the Crease Line and Bantry Bay transects between 20 and 70 m depth, with maximal cell concentrations of 7000 and 470,000 cells/L, respectively. Azaspiracid concentrations were well aligned with the distributions of Az. spinosum and Am. languida, up to 1.1 ng/L and 4.9 ng/L for combined AZA-1, -2, -33, and combined AZA-38, -39, respectively. Although a snapshot in time, this survey provides new insights in the late summer prominence of AZAs and AZA-producing species in the southwest of Ireland, where major shellfish aquaculture operations are located. Results showed a substantial overlap in the distribution of amphidomatacean species in the area and provide valuable baseline information in the context of ongoing monitoring efforts of toxigenic amphidomataceans in the region.
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Affiliation(s)
- Stephen McGirr
- School of Science, Department of Environmental Science, Innovation and Sustainability, Institute of Technology Sligo, Centre for Environmental Research, Ash Lane, Sligo, F91 YW50, Ireland.
| | - Dave Clarke
- Shellfish Safety, Marine Institute, Rinville, Oranmore, Co. Galway, H91 R673, Ireland
| | - Jane Kilcoyne
- Shellfish Safety, Marine Institute, Rinville, Oranmore, Co. Galway, H91 R673, Ireland
| | - Joe Silke
- Shellfish Safety, Marine Institute, Rinville, Oranmore, Co. Galway, H91 R673, Ireland
| | - Nicolas Touzet
- School of Science, Department of Environmental Science, Innovation and Sustainability, Institute of Technology Sligo, Centre for Environmental Research, Ash Lane, Sligo, F91 YW50, Ireland
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Sandvik M, Miles CO, Løvberg KLE, Kryuchkov F, Wright EJ, Mudge EM, Kilcoyne J, Samdal IA. In Vitro Metabolism of Azaspiracids 1-3 with a Hepatopancreatic Fraction from Blue Mussels ( Mytilus edulis). JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2021; 69:11322-11335. [PMID: 34533950 DOI: 10.1021/acs.jafc.1c03831] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Azaspiracids (AZAs) are a group of biotoxins produced by the marine dinoflagellates Azadinium and Amphidoma spp. that can accumulate in shellfish and cause food poisoning in humans. Of the 60 AZAs identified, levels of AZA1, AZA2, and AZA3 are regulated in shellfish as a food safety measure based on occurrence and toxicity. Information about the metabolism of AZAs in shellfish is limited. Therefore, a fraction of blue mussel hepatopancreas was made to study the metabolism of AZA1-3 in vitro. A range of AZA metabolites were detected by liquid chromatography-high-resolution tandem mass spectrometry analysis, most notably the novel 22α-hydroxymethylAZAs AZA65 and AZA66, which were also detected in naturally contaminated mussels. These appear to be the first intermediates in the metabolic conversion of AZA1 and AZA2 to their corresponding 22α-carboxyAZAs (AZA17 and AZA19). α-Hydroxylation at C-23 was also a prominent metabolic pathway, producing AZA8, AZA12, and AZA5 as major metabolites of AZA1-3, respectively, and AZA67 and AZA68 as minor metabolites via double-hydroxylation of AZA1 and AZA2, but only low levels of 3β-hydroxylation were observed in this study. In vitro generation of algal toxin metabolites, such as AZA3, AZA5, AZA6, AZA8, AZA12, AZA17, AZA19, AZA65, and AZA66 that would otherwise have to be laboriously purified from shellfish, has the potential to be used for the production of standards for analytical and toxicological studies.
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Affiliation(s)
- Morten Sandvik
- Norwegian Veterinary Institute, P.O. Box 64, N-1431 Ås, Norway
| | - Christopher O Miles
- Norwegian Veterinary Institute, P.O. Box 64, N-1431 Ås, Norway
- Biotoxin Metrology, National Research Council Canada, Halifax, NS B3H 3Z1, Canada
| | | | - Fedor Kryuchkov
- Norwegian Veterinary Institute, P.O. Box 64, N-1431 Ås, Norway
| | - Elliott J Wright
- Biotoxin Metrology, National Research Council Canada, Halifax, NS B3H 3Z1, Canada
| | - Elizabeth M Mudge
- Biotoxin Metrology, National Research Council Canada, Halifax, NS B3H 3Z1, Canada
| | - Jane Kilcoyne
- Marine Institute, Rinville, Oranmore, County Galway H91 R673, Ireland
| | - Ingunn A Samdal
- Norwegian Veterinary Institute, P.O. Box 64, N-1431 Ås, Norway
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Antioxidant Compounds from Microalgae: A Review. Mar Drugs 2021; 19:md19100549. [PMID: 34677448 PMCID: PMC8537667 DOI: 10.3390/md19100549] [Citation(s) in RCA: 47] [Impact Index Per Article: 15.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2021] [Revised: 09/23/2021] [Accepted: 09/24/2021] [Indexed: 02/08/2023] Open
Abstract
The demand for natural products isolated from microalgae has increased over the last decade and has drawn the attention from the food, cosmetic and nutraceutical industries. Among these natural products, the demand for natural antioxidants as an alternative to synthetic antioxidants has increased. In addition, microalgae combine several advantages for the development of biotechnological applications: high biodiversity, photosynthetic yield, growth, productivity and a metabolic plasticity that can be orientated using culture conditions. Regarding the wide diversity of antioxidant compounds and mode of action combined with the diversity of reactive oxygen species (ROS), this review covers a brief presentation of antioxidant molecules with their role and mode of action, to summarize and evaluate common and recent assays used to assess antioxidant activity of microalgae. The aim is to improve our ability to choose the right assay to assess microalgae antioxidant activity regarding the antioxidant molecules studied.
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Ozawa M, Uchida H, Watanabe R, Matsushima R, Oikawa H, Takahashi K, Iwataki M, Suzuki T. Complex profiles of azaspiracid analogues in two culture strains of Azadinium poporum (Amphidomataceae, Dinophyceae) isolated from Japanese coastal waters determined by LC-MS/MS. Toxicon 2021; 199:145-155. [PMID: 34166679 DOI: 10.1016/j.toxicon.2021.06.010] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2021] [Revised: 06/10/2021] [Accepted: 06/15/2021] [Indexed: 10/21/2022]
Abstract
Lipophilic marine biotoxins azaspiracids (AZAs) are produced by dinoflagellates Azadinium and Amphidoma. Recently, several strains of Azadinium poporum were isolated from Japanese coastal waters. In our present study, AZA analogues in two strains (mdd421 and HM536) of A. poporum were analyzed by several detection techniques on the liquid chromatography-tandem mass spectrometry (LC-MS/MS) and liquid chromatography-quadrupole time of flight mass spectrometry (LC-QTOFMS). The dominant AZA analogue in the Japanese A. poporum strains was AZA2. Other known AZA analogues were AZA11, AZA35, AZA2 methyl ester and AZA2 phosphate ester. Besides these AZAs, thirteen new AZA analogues were discovered in the two strains. A putative AZA analogue (Compound 1) with the smallest molecular weight ever found in nature was also discovered in the two strains. This is the first report describing detailed AZA profiles in Japanese isolates of A. poporum.
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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.
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Wright EJ, McCarron P. A mussel tissue certified reference material for multiple phycotoxins. Part 5: profiling by liquid chromatography-high-resolution mass spectrometry. Anal Bioanal Chem 2021; 413:2055-2069. [PMID: 33661347 DOI: 10.1007/s00216-020-03133-2] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2020] [Revised: 12/14/2020] [Accepted: 12/16/2020] [Indexed: 02/07/2023]
Abstract
A freeze-dried mussel tissue-certified reference material (CRM-FDMT1) was prepared containing the marine algal toxin classes azaspiracids, okadaic acid and dinophysistoxins, yessotoxins, pectenotoxins, cyclic imines, and domoic acid. Thus far, only a limited number of analogues in CRM-FDMT1 have been assigned certified values; however, the complete toxin profile is significantly more complex. Liquid chromatography-high-resolution mass spectrometry was used to profile CRM-FDMT1. Full-scan data was searched against a list of previously reported toxin analogues, and characteristic product ions extracted from all-ion-fragmentation data were used to guide the extent of toxin profiling. A series of targeted and untargeted acquisition MS/MS experiments were then used to collect spectra for analogues. A number of toxins previously reported in the literature but not readily available as standards were tentatively identified including dihydroxy and carboxyhydroxyyessotoxin, azaspiracids-33 and -39, sulfonated pectenotoxin analogues, spirolide variants, and fatty acid acyl esters of okadaic acid and pectenotoxins. Previously unreported toxins were also observed including compounds from the pectenotoxin, azaspiracid, yessotoxin, and spirolide classes. More than one hundred toxin analogues present in CRM-FDMT1 are summarized along with a demonstration of the major acyl ester conjugates of several toxins. Retention index values were assigned for all confirmed or tentatively identified analogues to help with qualitative identification of the broad range of lipophilic toxins present in the material.
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Affiliation(s)
- Elliott J Wright
- Biotoxin Metrology, National Research Council Canada, 1411 Oxford Street, Halifax, Nova Scotia, B3H 3Z1, Canada
| | - Pearse McCarron
- Biotoxin Metrology, National Research Council Canada, 1411 Oxford Street, Halifax, Nova Scotia, B3H 3Z1, Canada.
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Schrenk D, Bignami M, Bodin L, del Mazo J, Grasl‐Kraupp B, Hogstrand C, Chipman KJ, Leblanc J, Nebbia CS, Nielsen E, Ntzani E, Petersen A, Sand S, Schwerdtle T, Vleminckx C, Wallace H, Martinez AG, Gerssen A, Tubaro A, Cascio C, Abrahantes JC, Steinkellner H, Hoogenboom L(R. Evaluation of the shucking of certain species of scallops contaminated with lipophilic toxins with a view to the production of edible parts meeting the safety requirements foreseen in the Union legislation. EFSA J 2021; 19:e06422. [PMID: 33732388 PMCID: PMC7942228 DOI: 10.2903/j.efsa.2021.6422] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
Abstract
EFSA was asked by the European Commission to provide information on levels of lipophilic shellfish toxins in whole scallops that would ensure levels in edible parts below the regulatory limits after shucking, i.e. removal of non-edible parts. This should include the okadaic acid (OA), the azaspiracid (AZA) and the yessotoxin (YTX) groups, and five species of scallops. In addition, EFSA was asked to recommend the number of scallops in an analytical sample. To address these questions, EFSA received suitable data on the three toxin groups in two scallop species, Aequipecten opercularis and Pecten maximus, i.e. data on individual and pooled samples of edible and non-edible parts from contamination incidents. The majority of the concentration levels were below limit of quantification (LOQ)/limit of detection (LOD), especially in adductor muscle but also in gonads. Shucking in most cases resulted in a strong decrease in the toxin levels. For Pecten maximus, statistical analysis showed that levels in whole scallops should not exceed 256 μg OA eq/kg or 217 μg AZA1 eq/kg to ensure that levels in gonads are below the regulatory limits of 160 μg OA or AZA1 eq/kg with 99% certainty. Such an analysis was not possible for yessotoxins or any toxin in Aequipecten opercularis and an assessment could only be based on upper bound levels. To ensure a 95% correct prediction on whether the level in scallops in an area or lot is correctly predicted to be compliant/non-compliant, it was shown that 10 scallops per sample would be sufficient to predict with 95% certainty if levels of OA-group toxins in the area/lot were 25% below or above the regulatory limit. However, to predict with a 95% certainty for levels between 140 and 180 μg OA eq/kg, a pooled sample of more than 30 scallops would have to be tested.
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Tillmann U, Wietkamp S, Gu H, Krock B, Salas R, Clarke D. Multiple New Strains of Amphidomataceae (Dinophyceae) from the North Atlantic Revealed a High Toxin Profile Variability of Azadinium spinosum and a New Non-Toxigenic Az. cf. spinosum. Microorganisms 2021; 9:microorganisms9010134. [PMID: 33430155 PMCID: PMC7826828 DOI: 10.3390/microorganisms9010134] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2020] [Revised: 01/04/2021] [Accepted: 01/07/2021] [Indexed: 12/13/2022] Open
Abstract
Azaspiracids (AZA) are a group of lipophilic toxins, which are produced by a few species of the marine nanoplanktonic dinoflagellates Azadinium and Amphidoma (Amphidomataceae). A survey was conducted in 2018 to increase knowledge on the diversity and distribution of amphidomatacean species and their toxins in Irish and North Sea waters (North Atlantic). We here present a detailed morphological, phylogenetic, and toxinological characterization of 82 new strains representing the potential AZA producers Azadinium spinosum and Amphidoma languida. A total of ten new strains of Am. languida were obtained from the North Sea, and all conformed in terms of morphology and toxin profile (AZA-38 and-39) with previous records from the area. Within 72 strains assigned to Az. spinosum there were strains of two distinct ribotypes (A and B) which consistently differed in their toxin profile (dominated by AZA-1 and -2 in ribotype A, and by AZA-11 and -51 in ribotype B strains). Five strains conformed in morphology with Az. spinosum, but no AZA could be detected in these strains. Moreover, they revealed significant nucleotide differences compared to known Az. spinosum sequences and clustered apart from all other Az. spinosum strains within the phylogenetic tree, and therefore were provisionally designated as Az. cf. spinosum. These Az. cf. spinosum strains without detectable AZA were shown not to cause amplification in the species-specific qPCR assay developed to detect and quantify Az. spinosum. As shown here for the first time, AZA profiles differed between strains of Az. spinosum ribotype A in the presence/absence of AZA-1, AZA-2, and/or AZA-33, with the majority of strains having all three AZA congeners, and others having only AZA-1, AZA-1 and AZA-2, or AZA-1 and AZA-33. In contrast, no AZA profile variability was observed in ribotype B strains. Multiple AZA analyses of a period of up to 18 months showed that toxin profiles (including absence of AZA for Az. cf. spinosum strains) were consistent and stable over time. Total AZA cell quotas were highly variable both among and within strains, with quotas ranging from 0.1 to 63 fg AZA cell−1. Cell quota variability of single AZA compounds for Az. spinosum strains could be as high as 330-fold, but the underlying causes for the extraordinary large variability of AZA cell quota is poorly understood.
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Affiliation(s)
- Urban Tillmann
- Helmholtz Center for Polar and Marine Research, Alfred Wegener Institute, Am Handelshafen 12, D-27570 Bremerhaven, Germany; (S.W.); (B.K.)
- Correspondence: ; Tel.: +49-471-4831-1470
| | - Stephan Wietkamp
- Helmholtz Center for Polar and Marine Research, Alfred Wegener Institute, Am Handelshafen 12, D-27570 Bremerhaven, Germany; (S.W.); (B.K.)
| | - Haifeng Gu
- Third Institute of Oceanography, Ministry of Natural Resources, Xiamen 361005, China;
- School of Marine Sciences, Nanjing University of Information Science and Technology, Nanjing 210044, China
| | - Bernd Krock
- Helmholtz Center for Polar and Marine Research, Alfred Wegener Institute, Am Handelshafen 12, D-27570 Bremerhaven, Germany; (S.W.); (B.K.)
| | - Rafael Salas
- Marine Institute, Rinville, Oranmore, H91 R673 Co. Galway, Ireland; (R.S.); (D.C.)
| | - Dave Clarke
- Marine Institute, Rinville, Oranmore, H91 R673 Co. Galway, Ireland; (R.S.); (D.C.)
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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.
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Adams NG, Tillmann U, Trainer VL. Temporal and spatial distribution of Azadinium species in the inland and coastal waters of the Pacific northwest in 2014-2018. HARMFUL ALGAE 2020; 98:101874. [PMID: 33129464 DOI: 10.1016/j.hal.2020.101874] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/07/2020] [Revised: 07/20/2020] [Accepted: 07/22/2020] [Indexed: 06/11/2023]
Abstract
Azaspiracids, produced by some species of the dinoflagellate genera Azadinium and Amphidoma, can cause a syndrome in humans called azaspiracid shellfish poisoning (AZP). In 1995, mussels from the Irish west coast contaminated with azaspiracids were, for the first time, linked to this human illness that has symptoms of nausea, vomiting, severe diarrhea, and stomach cramps. The only confirmed cases of AZP to date in the United States occurred in Washington State in 2008 from mussels imported from Ireland. Shortly after this case, several others involving similar gastrointestinal symptoms were reported by shellfish consumers from Washington State. However, no detectable diarrhetic shellfish toxins or Vibrio contamination were found. Cursory analysis of Solid Phase Adsorption Toxin Tracking (SPATT) samplers suggested the presence of azaspiracids in Washington State waters and motivated a study to evaluate the presence and distribution of Azadinium species in the region. During the spring and summer months of 2014-2015, quantitative polymerase chain reaction (qPCR) analyses detected the presence of the toxigenic species Azadinium poporum and A. spinosum on the outer coast and throughout the inland waters of Washington State. In 2016-2018, standard curves developed using A. poporum isolated from Puget Sound and A. spinosum isolated from the North Sea were used to quantify abundances of up to 10,525 cells L-1 of A. poporum and 156 cells L-1 of A. spinosum at shore-based sites. Abundances up to 1,206 cells L-1 of A. poporum and 30 cells L-1 of A. spinosum were measured in the coastal waters of the Pacific Northwest in 2017. Other harmful genera, including Alexandrium, Dinophysis, and Pseudo-nitzschia, were observed using light microscopy at coastal sites where A. poporum was also observed. In some samples where both A. poporum and A. spinosum were absent, an Amphidomataceae-specific qPCR assay indicated that other species of Azadinium or Amphidoma were present. The identification of Azadinium species in the PNW demonstrates the need to assess their toxicity and to incorporate their routine detection in monitoring programs to aid resource managers in mitigating risks to azaspiracid shellfish poisoning in this region.
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Affiliation(s)
- Nicolaus G Adams
- Environmental and Fisheries Science Division, Northwest Fisheries Science Center, National Marine Fisheries Service, National Oceanic and Atmospheric Administration, 2725 Montlake Blvd. E., Seattle, WA 98112, USA.
| | - Urban Tillmann
- Alfred Wegener Institute for Polar and Marine Research, Am Handelshafen 12 D-27570 Bremerhaven, Germany
| | - Vera L Trainer
- Environmental and Fisheries Science Division, Northwest Fisheries Science Center, National Marine Fisheries Service, National Oceanic and Atmospheric Administration, 2725 Montlake Blvd. E., Seattle, WA 98112, USA
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Qiu J, Wright EJ, Thomas K, Li A, McCarron P, Beach DG. Semiquantitation of Paralytic Shellfish Toxins by Hydrophilic Interaction Liquid Chromatography-Mass Spectrometry Using Relative Molar Response Factors. Toxins (Basel) 2020; 12:toxins12060398. [PMID: 32560098 PMCID: PMC7354571 DOI: 10.3390/toxins12060398] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2020] [Revised: 06/10/2020] [Accepted: 06/12/2020] [Indexed: 12/30/2022] Open
Abstract
Paralytic shellfish toxins (PSTs) are a complex class of analogs of the potent neurotoxin saxitoxin (STX). Since calibration standards are not available for many PSTs, including C-11 hydroxyl analogs called M-toxins, accurate quantitation by liquid chromatography–mass spectrometry (LC-MS) can be challenging. In the absence of standards, PSTs are often semiquantitated using standards of a different analog (e.g., STX), an approach with a high degree of uncertainty due to the highly variable sensitivity between analytes in electrospray ionization. Here, relative molar response factors (RMRs) were investigated for a broad range of PSTs using common LC-MS approaches in order to improve the quantitation of PSTs for which standards are unavailable. First, several M-toxins (M1-M6, M9 and dcM6) were semipurified from shellfish using preparative gel filtration chromatography and quantitated using LC-charged aerosol detection (LC-CAD). The RMRs of PST certified reference materials (CRMs) and M-toxins were then determined using selective reaction monitoring LC-MS/MS and full scan LC-high-resolution MS (LC-HRMS) methods in positive and negative electrospray ionization. In general, RMRs for PSTs with similar chemical structures were comparable, but varied significantly between subclasses, with M-toxins showing the lowest sensitivity. For example, STX showed a greater than 50-fold higher RMR than M4 and M6 by LC-HRMS. The MS instrument, scan mode and polarity also had significant impacts on RMRs and should be carefully considered when semiquantitating PSTs by LC-MS. As a demonstration of their utility, the RMRs determined were applied to the semiquantitation of PSTs in contaminated mussels, showing good agreement with results from calibration with CRMs.
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Affiliation(s)
- Jiangbing Qiu
- College of Fisheries, Ocean University of China, Qingdao 266003, China;
| | - Elliott J. Wright
- Biotoxin Metrology, National Research Council Canada, 1411 Oxford St, Halifax, NS B3H 3Z1, Canada; (E.J.W.); (K.T.); (P.M.)
| | - Krista Thomas
- Biotoxin Metrology, National Research Council Canada, 1411 Oxford St, Halifax, NS B3H 3Z1, Canada; (E.J.W.); (K.T.); (P.M.)
| | - 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
| | - Pearse McCarron
- Biotoxin Metrology, National Research Council Canada, 1411 Oxford St, Halifax, NS B3H 3Z1, Canada; (E.J.W.); (K.T.); (P.M.)
| | - Daniel G. Beach
- Biotoxin Metrology, National Research Council Canada, 1411 Oxford St, Halifax, NS B3H 3Z1, Canada; (E.J.W.); (K.T.); (P.M.)
- Correspondence: ; Tel.: +1-(902)-426-8274
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Effects of Temperature, Growth Media, and Photoperiod on Growth and Toxin Production of Azadinium spinosum. Mar Drugs 2019; 17:md17090489. [PMID: 31443393 PMCID: PMC6780083 DOI: 10.3390/md17090489] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2019] [Revised: 08/13/2019] [Accepted: 08/16/2019] [Indexed: 01/02/2023] Open
Abstract
Azaspiracids (AZAs) are microalgal toxins that can accumulate in shellfish and lead to human intoxications. To facilitate their study and subsequent biomonitoring, purification from microalgae rather than shellfish is preferable; however, challenges remain with respect to maximizing toxin yields. The impacts of temperature, growth media, and photoperiod on cell densities and toxin production in Azadinium spinosum were investigated. Final cell densities were similar at 10 and 18 °C, while toxin cell quotas were higher (~3.5-fold) at 10 °C. A comparison of culture media showed higher cell densities and AZA cell quotas (2.5-5-fold) in f10k compared to f/2 and L1 media. Photoperiod also showed differences, with lower cell densities in the 8:16 L:D treatment, while toxin cell quotas were similar for 12:12 and 8:16 L:D treatments but slightly lower for the 16:8 L:D treatment. AZA1, -2 and -33 were detected during the exponential phase, while some known and new AZAs were only detected once the stationary phase was reached. These compounds were additionally detected in field water samples during an AZA event.
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16
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Dhanji-Rapkova M, O'Neill A, Maskrey BH, Coates L, Swan SC, Teixeira Alves M, Kelly RJ, Hatfield RG, Rowland-Pilgrim SJ, Lewis AM, Turner AD. Variability and profiles of lipophilic toxins in bivalves from Great Britain during five and a half years of monitoring: azaspiracids and yessotoxins. HARMFUL ALGAE 2019; 87:101629. [PMID: 31349886 DOI: 10.1016/j.hal.2019.101629] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/22/2019] [Revised: 05/04/2019] [Accepted: 06/11/2019] [Indexed: 06/10/2023]
Abstract
Cefas has been responsible for the delivery of official control biotoxin testing of bivalve molluscs from Great Britain for just over a decade. Liquid chromatography tandem mass spectrometric (LC-MS/MS) methodology has been used for the quantitation of lipophilic toxins (LTs) since 2011. The temporal and spatial distribution of okadaic acid group toxins and profiles in bivalves between 2011 and 2016 have been recently reported. Here we present data on the two other groups of regulated lipophilic toxins, azaspiracids (AZAs) and yessotoxins (YTXs), over the same period. The latter group has also been investigated for a potential link with Protoceratium reticulatum and Lingulodinium polyedra, both previously recognised as YTXs producing phytoplankton. On average, AZAs were quantified in 3.2% of all tested samples but notable inter-annual variation in abundance was observed. The majority of all AZA contaminated samples were found between July 2011 and August 2013 in Scotland, while only two, three-month long, AZA events were observed in 2015 and 2016 in the south-west of England. Maximum concentrations were generally reached in late summer or early autumn. Reasons for AZAs persistence during the 2011/2012 and 2012/2013 winters are discussed. Only one toxin profile was identified, represented by both AZA1 and AZA2 toxins at an approximate ratio of 2 : 1, suggesting a single microalgal species was the source of AZAs in British bivalves. Although AZA1 was always the most dominant toxin, its proportion varied between mussels, Pacific oysters and surf clams. The YTXs were the least represented group among regulated LTs. YTXs were found almost exclusively on the south-west coast of Scotland, with the exception of 2013, when the majority of contaminated samples originated from the Shetland Islands. The highest levels were recorded in the summer months and followed a spike in Protoceratium reticulatum cell densities. YTX was the most dominant toxin in shellfish, further strengthening the link to P. reticulatum as the YTX source. Neither homo-YTX, nor 45-OH homo-YTX were detected throughout the monitored period. 45-OH YTX, thought to be a shellfish metabolite associated with YTX elimination, contributed on average 26% in mussels. Although the correlation between 45-OH YTX abundance and the speed of YTX depuration could not be confirmed, we noted the half-life of YTX was more than two-times longer in queen scallops, which contained 100% YTX, than in mussels. No other bivalve species were affected by YTXs. This is the first detailed evaluation of AZAs and YTXs occurrences and their profiles in shellfish from Great Britain over a period of multiple years.
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Affiliation(s)
- Monika Dhanji-Rapkova
- Centre for Environment, Fisheries and Aquaculture Science (Cefas), The Nothe, Barrack Road, Weymouth, Dorset, DT4 8UB, United Kingdom.
| | - Alison O'Neill
- Centre for Environment, Fisheries and Aquaculture Science (Cefas), The Nothe, Barrack Road, Weymouth, Dorset, DT4 8UB, United Kingdom
| | - Benjamin H Maskrey
- Centre for Environment, Fisheries and Aquaculture Science (Cefas), The Nothe, Barrack Road, Weymouth, Dorset, DT4 8UB, United Kingdom
| | - Lewis Coates
- Centre for Environment, Fisheries and Aquaculture Science (Cefas), The Nothe, Barrack Road, Weymouth, Dorset, DT4 8UB, United Kingdom
| | - Sarah C Swan
- Scottish Association for Marine Science (SAMS), Scottish Marine Institute, Oban, Argyll, PA37 1QA, Scotland, United Kingdom
| | - Mickael Teixeira Alves
- Centre for Environment, Fisheries and Aquaculture Science (Cefas), The Nothe, Barrack Road, Weymouth, Dorset, DT4 8UB, United Kingdom
| | - Rebecca J Kelly
- Centre for Environment, Fisheries and Aquaculture Science (Cefas), The Nothe, Barrack Road, Weymouth, Dorset, DT4 8UB, United Kingdom
| | - Robert G Hatfield
- Centre for Environment, Fisheries and Aquaculture Science (Cefas), The Nothe, Barrack Road, Weymouth, Dorset, DT4 8UB, United Kingdom
| | - Stephanie J Rowland-Pilgrim
- Centre for Environment, Fisheries and Aquaculture Science (Cefas), The Nothe, Barrack Road, Weymouth, Dorset, DT4 8UB, United Kingdom
| | - Adam M Lewis
- Centre for Environment, Fisheries and Aquaculture Science (Cefas), The Nothe, Barrack Road, Weymouth, Dorset, DT4 8UB, United Kingdom
| | - Andrew D Turner
- Centre for Environment, Fisheries and Aquaculture Science (Cefas), The Nothe, Barrack Road, Weymouth, Dorset, DT4 8UB, United Kingdom
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17
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Samdal IA, Løvberg KE, Kristoffersen AB, Briggs LR, Kilcoyne J, Forsyth CJ, Miles CO. A Practical ELISA for Azaspiracids in Shellfish via Development of a New Plate-Coating Antigen. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2019; 67:2369-2376. [PMID: 30763083 DOI: 10.1021/acs.jafc.8b05652] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Azaspiracids (AZAs) are a group of biotoxins that appear periodically in shellfish and can cause food poisoning in humans. Current methods for quantifying the regulated AZAs are restricted to LC-MS but are not well suited to detecting novel and unregulated AZAs. An ELISA method for total AZAs in shellfish was reported recently, but unfortunately, it used relatively large amounts of the AZA-1-containing plate-coating conjugate, consuming significant amounts of pure AZA-1 per assay. Therefore, a new plate-coater, OVA-cdiAZA1 was produced, resulting in an ELISA with a working range of 0.30-4.1 ng/mL and a limit of quantification of 37 μg/kg for AZA-1 in shellfish. This ELISA was nearly twice as sensitive as the previous ELISA while using 5-fold less plate-coater. The new ELISA displayed broad cross-reactivity toward AZAs, detecting all available quantitative AZA reference materials as well as the precursors to AZA-3 and AZA-6, and results from shellfish analyzed with the new ELISA showed excellent correlation ( R2 = 0.99) with total AZA-1-10 by LC-MS. The results suggest that the new ELISA is suitable for screening samples for total AZAs, even in cases where novel AZAs are present and regulated AZAs are absent, such as was reported recently from Puget Sound and the Bay of Naples.
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Affiliation(s)
- Ingunn A Samdal
- Norwegian Veterinary Institute , P.O. Box 750 Sentrum, N-0106 Oslo , Norway
| | - Kjersti E Løvberg
- Norwegian Veterinary Institute , P.O. Box 750 Sentrum, N-0106 Oslo , Norway
| | | | - Lyn R Briggs
- AgResearch Ltd., Ruakura Research Centre , Hamilton 3214 , New Zealand
| | - Jane Kilcoyne
- Marine Institute , Rinville, Oranmore, County Galway H91 R673 , Ireland
| | - Craig J Forsyth
- Department of Chemistry and Biochemistry , The Ohio State University , Columbus , Ohio 43220 , United States
| | - Christopher O Miles
- Norwegian Veterinary Institute , P.O. Box 750 Sentrum, N-0106 Oslo , Norway
- National Research Council Canada , 1411 Oxford St , Halifax , NS B3H 3Z1 , Canada
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Krock B, Tillmann U, Tebben J, Trefault N, Gu H. Two novel azaspiracids from Azadinium poporum, and a comprehensive compilation of azaspiracids produced by Amphidomataceae, (Dinophyceae). HARMFUL ALGAE 2019; 82:1-8. [PMID: 30928006 DOI: 10.1016/j.hal.2018.12.005] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/16/2018] [Revised: 11/26/2018] [Accepted: 12/18/2018] [Indexed: 06/09/2023]
Abstract
Two novel azaspiracids (AZA) with a molecular mass of 869 Da were found in Pacific strains of Azadinium poporum and characterized by tandem mass spectrometry and high resolution mass spectrometry (HRMS). One compound, AZA-42, was found in Az. poporum strains AZFC25 and AZFC26, both isolated from the South China Sea. AZA-42 belongs to the 360-type AZA that in comparison to AZA-1 has an additional double bond in the F-I ring system of AZA comprising C28-C40. The other compound, AZA-62, was detected in Az. poporum strain 1D5 isolated off Chañaral, Northern Chile. Mass spectral data indicate that AZA-62 is a variant of AZA-11 with an additional double bond in the C1-C9 region of AZA. In addition to the description of the two novel AZA, a comprehensive list of all AZA known to be produced by species of the genera Azadinium and Amphidoma comprising 26 AZA variants is presented.
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Affiliation(s)
- Bernd Krock
- Alfred Wegener Institut-Helmholtz Zentrum für Polar- und Meeresforschung, Am Handelshafen 12, 27570 Bremerhaven, Germany.
| | - Urban Tillmann
- Alfred Wegener Institut-Helmholtz Zentrum für Polar- und Meeresforschung, Am Handelshafen 12, 27570 Bremerhaven, Germany
| | - Jan Tebben
- Alfred Wegener Institut-Helmholtz Zentrum für Polar- und Meeresforschung, Am Handelshafen 12, 27570 Bremerhaven, Germany
| | - Nicole Trefault
- GEMA Center for Genomics, Ecology & Environment, Faculty of Sciences, Universidad Mayor, Camino La Pirámide 5750, Huechuraba, Santiago, Chile
| | - Haifeng Gu
- Third Institute of Oceanography, State Oceanic Administration, Xiamen 361005, China
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Abstract
Azaspiracid-34 (AZA34) is a recently described structurally unique member of the azaspiracid class of marine neurotoxins. Its novel structure, tentatively assigned on the basis of MS and 1H NMR spectroscopy, is accompanied by a 5.5-fold higher level of toxicity against Jurkat T lymphocytes than AZA1. To completely assign the structure of AZA34 and provide material for in-depth biological evaluation and detection, synthetic access to AZA34 was targeted. This began with the convergent and stereoselective assembly of the C1-C19 domain of AZA34 designed to dovetail with the recent total synthesis approach to AZA3.
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Affiliation(s)
- Antony A Okumu
- Department of Chemistry and Biochemistry , The Ohio State University , Columbus , Ohio 43210 , United States
| | - Craig J Forsyth
- Department of Chemistry and Biochemistry , The Ohio State University , Columbus , Ohio 43210 , United States
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20
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Tillmann U, Edvardsen B, Krock B, Smith KF, Paterson RF, Voß D. Diversity, distribution, and azaspiracids of Amphidomataceae (Dinophyceae) along the Norwegian coast. HARMFUL ALGAE 2018; 80:15-34. [PMID: 30502808 DOI: 10.1016/j.hal.2018.08.011] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/11/2018] [Revised: 08/27/2018] [Accepted: 08/30/2018] [Indexed: 06/09/2023]
Abstract
Azaspiracids (AZA) are a group of lipophilic polyether compounds which have been implicated in shellfish poisoning incidents around Europe. They are produced by a few species of the dinophycean genera Azadinium and Amphidoma (Amphidomataceae). The presence of AZA toxins in Norway is well documented, but knowledge of the distribution and diversity of Azadinium and other Amphidomataceae along the Norwegian coast is rather limited and poorly documented. On a research survey along the Norwegian coast in 2015 from the Skagerrak in the South to Trondheimsfjorden in the North, plankton samples from 67 stations were analysed for the presence of Azadinium and Amphidoma and their respective AZA by on-board live microscopy, real-time PCR assays specific for Amphidomataceae, and liquid chromatography-tandem mass spectrometry (LC-MS/MS). Microscopy using live samples and positive real-time PCR assays using a general family probe and two species specific probes revealed the presence of Amphidomataceae distributed throughout the sampling area. Overall abundance was low, however, and was in agreement with a lack of detectable AZA in plankton samples. Single cell isolation and morphological and molecular characterisation of established strains revealed the presence of 7 amphidomatacean species (Azadiniun spinosum, Az. poporum, Az. obesum, Az. dalianense, Az. trinitatum, Az. polongum, Amphidoma languida) in the area. Azaspiracids were produced by the known AZA producing species Az. spinosum, Az. poporum and Am. languida only. LC-MS/MS analysis further revealed that Norwegian strains produce previously unreported AZA for Norway (AZA-11 by Az. spinosum, AZA-37 by Az. poporum, AZA-38 and AZA-39 by Am. languida), and also four novel compounds (AZA-50, -51 by Az. spinosum, AZA-52, -53 by Am. languida), whose structural properties are described and which now can be included in existing analytical protocols. A maximum likelihood analysis of concatenated rDNA regions (SSU, ITS1-ITS2, partial LSU) showed that the strains of Az. spinosum fell in two well supported clades, where most but not all new Norwegian strains formed the new Ribotype B. Ribotype differentiation was supported by a minor morphological difference with respect to the presence/absence of a rim around the pore plate, and was consistently reflected by different AZA profiles. Strains of Az. spinosum from ribotype A produce AZA-1, -2 and -33, whereas the new strains of ribotype B produce mainly AZA-11 and AZA-51. Significant sequence differences between both Az. spinosum ribotypes underline the need to redesign the currently used qPCR probes in order to detect all AZA producing Az. spinosum. The results generally underline the conclusion that for the Norwegian coast area it is important that amphidomatacean species are taken into account in future studies and monitoring programs.
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Affiliation(s)
- Urban Tillmann
- Alfred Wegener Institute, Am Handelshafen 12, D-27570 Bremerhaven, Germany.
| | - Bente Edvardsen
- University of Oslo, Department of Biosciences, Section for Aquatic Biology and Toxicology, P.O. Box 1066 Blindern, 0316 Oslo, Norway
| | - Bernd Krock
- Alfred Wegener Institute, Am Handelshafen 12, D-27570 Bremerhaven, Germany
| | - Kirsty F Smith
- Cawthron Institute, Privat Bag 2, Nelson 7042, New Zealand
| | - Ruth F Paterson
- Scottish Association for Marine Science, Scotland, PA37 1QA, United Kingdom
| | - Daniela Voß
- Institut für Chemie und Biologie des Meeres (ICBM), Carl von Ossietzky Universität Oldenburg, Schleusenstraße 1, D-26382 Wilhelmshaven, Germany
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Kilcoyne J, McCarron P, Twiner MJ, Rise F, Hess P, Wilkins AL, Miles CO. Identification of 21,22-Dehydroazaspiracids in Mussels ( Mytilus edulis) and in Vitro Toxicity of Azaspiracid-26. JOURNAL OF NATURAL PRODUCTS 2018; 81:885-893. [PMID: 29488755 DOI: 10.1021/acs.jnatprod.7b00973] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Azaspiracids (AZAs) are marine biotoxins produced by the genera Azadinium and Amphidoma, pelagic marine dinoflagellates that may accumulate in shellfish resulting in human illness following consumption. The complexity of these toxins has been well documented, with more than 40 structural variants reported that are produced by dinoflagellates, result from metabolism in shellfish, or are extraction artifacts. Approximately 34 μg of a new AZA with MW 823 Da (AZA26 (3)) was isolated from blue mussels ( Mytilus edulis), and its structure determined by MS and NMR spectroscopy. AZA26, possibly a bioconversion product of AZA5, lacked the C-20-C-21 diol present in all AZAs reported thus far and had a 21,22-olefin and a keto group at C-23. Toxicological assessment of 3 using an in vitro model system based on Jurkat T lymphocyte cells showed the potency to be ∼30-fold lower than that of AZA1. The corresponding 21,22-dehydro-23-oxo-analogue of AZA10 (AZA28) and 21,22-dehydro analogues of AZA3, -4, -5, -6, -9, and -10 (AZA25, -48 (4), -60, -27, -49, and -61, respectively) were also identified by HRMS/MS, periodate cleavage reactivity, conversion from known analogues, and NMR (for 4 that was present in a partially purified sample of AZA7).
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Affiliation(s)
- Jane Kilcoyne
- Marine Institute , Rinville, Oranmore , Co. Galway H91 R673 , Ireland
| | - Pearse McCarron
- Measurement Science and Standards , National Research Council Canada , Halifax , NS B3H 3Z1 , Canada
| | - Michael J Twiner
- Department of Emergency Medicine, Detroit Receiving Hospital , Wayne State University , Detroit , Michigan 48202 , United States
| | - Frode Rise
- Department of Chemistry , University of Oslo , N-0315 Oslo , Norway
| | - Philipp Hess
- Ifremer, Laboratoire Phycotoxines , Rue de l'Ile d'Yeu , 44311 Nantes , France
| | - Alistair L Wilkins
- Norwegian Veterinary Institute , P.O. Box 750 Sentrum, 0106 Oslo , Norway
| | - Christopher O Miles
- Measurement Science and Standards , National Research Council Canada , Halifax , NS B3H 3Z1 , Canada
- Norwegian Veterinary Institute , P.O. Box 750 Sentrum, 0106 Oslo , Norway
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Miles CO, Kilcoyne J, McCarron P, Giddings SD, Waaler T, Rundberget T, Samdal IA, Løvberg KE. Selective Extraction and Purification of Azaspiracids from Blue Mussels ( Mytilus edulis) Using Boric Acid Gel. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2018; 66:2962-2969. [PMID: 29502403 DOI: 10.1021/acs.jafc.8b00346] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Azaspiracids belong to a family of more than 50 polyether toxins originating from marine dinoflagellates such as Azadinium spinosum. All of the azaspiracids reported thus far contain a 21,22-dihydroxy group. Boric acid gel can bind selectively to compounds containing vic-diols or α-hydroxycarboxylic acids via formation of reversible boronate complexes. Here we report use of the gel to selectively capture and release azaspiracids from extracts of blue mussels. Analysis of the extracts and fractions by liquid chromatography-tandem mass spectrometry (LC-MS) showed that this procedure resulted in an excellent cleanup of the azaspiracids in the extract. Analysis by enzyme-linked immunoasorbent assay (ELISA) and LC-MS indicated that most azaspiracid analogues were recovered in good yield by this procedure. The capacity of boric acid gel for azaspiracids was at least 50 μg/g, making this procedure suitable for use in the early stages of preparative purification of azaspiracids. In addition to its potential for concentration of dilute samples, the extensive cleanup provided by boric acid gel fractionation of azaspiracids in mussel samples almost eliminated matrix effects during subsequent LC-MS and could be expected to reduce matrix effects during ELISA analysis. The method may therefore prove useful for quantitative analysis of azaspiracids as part of monitoring programs. Although LC-MS data showed that okadaic acid analogues also bound to the gel, this was much less efficient than for azaspiracids under the conditions used. The boric acid gel methodology is potentially applicable to other important groups of natural toxins containing diols including ciguatoxins, palytoxins, pectenotoxins, tetrodotoxin, trichothecenes, and toxin glycosides.
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Affiliation(s)
- Christopher O Miles
- Norwegian Veterinary Institute, P.O. Box 750 Sentrum , N-0106 Oslo , Norway
- Measurement Science and Standards , National Research Council , 1411 Oxford Street , Halifax , Nova Scotia B3H 3Z1 , Canada
| | - Jane Kilcoyne
- Marine Institute, Rinville, Oranmore, Co., Galway H91 R673 , Ireland
| | - Pearse McCarron
- Measurement Science and Standards , National Research Council , 1411 Oxford Street , Halifax , Nova Scotia B3H 3Z1 , Canada
| | - Sabrina D Giddings
- Measurement Science and Standards , National Research Council , 1411 Oxford Street , Halifax , Nova Scotia B3H 3Z1 , Canada
| | - Thor Waaler
- Norwegian Veterinary Institute, P.O. Box 750 Sentrum , N-0106 Oslo , Norway
| | - Thomas Rundberget
- Norwegian Veterinary Institute, P.O. Box 750 Sentrum , N-0106 Oslo , Norway
- Norwegian Institute for Water Research , N-0349 Oslo , Norway
| | - Ingunn A Samdal
- Norwegian Veterinary Institute, P.O. Box 750 Sentrum , N-0106 Oslo , Norway
| | - Kjersti E Løvberg
- Norwegian Veterinary Institute, P.O. Box 750 Sentrum , N-0106 Oslo , Norway
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23
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Kenton NT, Adu‐Ampratwum D, Okumu AA, McCarron P, Kilcoyne J, Rise F, Wilkins AL, Miles CO, Forsyth CJ. Stereochemical Definition of the Natural Product (6
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)‐Azaspiracid‐3 by Total Synthesis and Comparative Analyses. Angew Chem Int Ed Engl 2018; 57:810-813. [DOI: 10.1002/anie.201711008] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2017] [Indexed: 11/08/2022]
Affiliation(s)
- Nathaniel T. Kenton
- Department of Chemistry and BiochemistryThe Ohio State University 151 W. Woodruff Ave Columbus OH 43210 USA
| | - Daniel Adu‐Ampratwum
- Department of Chemistry and BiochemistryThe Ohio State University 151 W. Woodruff Ave Columbus OH 43210 USA
| | - Antony A. Okumu
- Department of Chemistry and BiochemistryThe Ohio State University 151 W. Woodruff Ave Columbus OH 43210 USA
| | - Pearse McCarron
- Measurement Science and StandardsNational Research Council of Canada 1411 Oxford St. Halifax Nova Scotia B3H 3Z1 Canada
| | - Jane Kilcoyne
- Marine Institute, RinvilleOranmore, Co. Galway Ireland
| | - Frode Rise
- Department of ChemistryUniversity of Oslo 0315 Oslo Norway
| | - Alistair L. Wilkins
- Norwegian Veterinary Institute P.O. Box 750 Sentrum 0106 Oslo Norway
- Chemistry DepartmentUniversity of Waikato Private Bag 3105 3240 Hamilton New Zealand
| | - Christopher O. Miles
- Measurement Science and StandardsNational Research Council of Canada 1411 Oxford St. Halifax Nova Scotia B3H 3Z1 Canada
- Norwegian Veterinary Institute P.O. Box 750 Sentrum 0106 Oslo Norway
| | - Craig J. Forsyth
- Department of Chemistry and BiochemistryThe Ohio State University 151 W. Woodruff Ave Columbus OH 43210 USA
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24
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Kenton NT, Adu‐Ampratwum D, Okumu AA, Zhang Z, Chen Y, Nguyen S, Xu J, Ding Y, McCarron P, Kilcoyne J, Rise F, Wilkins AL, Miles CO, Forsyth CJ. Total Synthesis of (6
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)‐Azaspiracid‐3 Reveals Non‐Identity with the Natural Product. Angew Chem Int Ed Engl 2018; 57:805-809. [DOI: 10.1002/anie.201711006] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2017] [Revised: 11/16/2017] [Indexed: 11/11/2022]
Affiliation(s)
- Nathaniel T. Kenton
- Department of Chemistry and BiochemistryThe Ohio State University 151 W. Woodruff Ave Columbus OH 43210 USA
| | - Daniel Adu‐Ampratwum
- Department of Chemistry and BiochemistryThe Ohio State University 151 W. Woodruff Ave Columbus OH 43210 USA
| | - Antony A. Okumu
- Department of Chemistry and BiochemistryThe Ohio State University 151 W. Woodruff Ave Columbus OH 43210 USA
| | - Zhigao Zhang
- Shanghai Hengrui Pharmaceutical Inc. No. 279 Wenjing Road Shanghai 200245 P. R. China
| | - Yong Chen
- Asymchem Life Science No. 71 7th Ave., TEDA Tianjin 300000 P. R. China
| | - Son Nguyen
- Johnson Matthey Pharma Services 25 Patton Road Devens MA 01434 USA
| | - Jianyan Xu
- Shanghai Hengrui Pharmaceutical Inc. No. 279 Wenjing Road Shanghai 200245 P. R. China
| | - Yue Ding
- Viva Biotech Ltd. 581 Shenkuo Rd., Pudong District Shanghai 201203 China
| | - Pearse McCarron
- Measurement Science and StandardsNational Research Council of Canada Halifax Nova Scotia B3H 3Z1 Canada
| | - Jane Kilcoyne
- Marine Institute, RinvilleOranmore, Co. Galway Ireland
| | - Frode Rise
- Department of ChemistryUniversity of Oslo 0315 Oslo Norway
| | - Alistair L. Wilkins
- Norwegian Veterinary Institute P.O. Box 750 Sentrum 0106 Oslo Norway
- Chemistry DepartmentUniversity of Waikato Private Bag 3105 3240 Hamilton New Zealand
| | - Christopher O. Miles
- Measurement Science and StandardsNational Research Council of Canada Halifax Nova Scotia B3H 3Z1 Canada
- Norwegian Veterinary Institute P.O. Box 750 Sentrum 0106 Oslo Norway
| | - Craig J. Forsyth
- Department of Chemistry and BiochemistryThe Ohio State University 151 W. Woodruff Ave Columbus OH 43210 USA
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25
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Kenton NT, Adu‐Ampratwum D, Okumu AA, McCarron P, Kilcoyne J, Rise F, Wilkins AL, Miles CO, Forsyth CJ. Stereochemical Definition of the Natural Product (6
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)‐Azaspiracid‐3 by Total Synthesis and Comparative Analyses. Angew Chem Int Ed Engl 2017. [DOI: 10.1002/ange.201711008] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- Nathaniel T. Kenton
- Department of Chemistry and BiochemistryThe Ohio State University 151 W. Woodruff Ave Columbus OH 43210 USA
| | - Daniel Adu‐Ampratwum
- Department of Chemistry and BiochemistryThe Ohio State University 151 W. Woodruff Ave Columbus OH 43210 USA
| | - Antony A. Okumu
- Department of Chemistry and BiochemistryThe Ohio State University 151 W. Woodruff Ave Columbus OH 43210 USA
| | - Pearse McCarron
- Measurement Science and StandardsNational Research Council of Canada 1411 Oxford St. Halifax Nova Scotia B3H 3Z1 Canada
| | - Jane Kilcoyne
- Marine Institute, RinvilleOranmore, Co. Galway Ireland
| | - Frode Rise
- Department of ChemistryUniversity of Oslo 0315 Oslo Norway
| | - Alistair L. Wilkins
- Norwegian Veterinary Institute P.O. Box 750 Sentrum 0106 Oslo Norway
- Chemistry DepartmentUniversity of Waikato Private Bag 3105 3240 Hamilton New Zealand
| | - Christopher O. Miles
- Measurement Science and StandardsNational Research Council of Canada 1411 Oxford St. Halifax Nova Scotia B3H 3Z1 Canada
- Norwegian Veterinary Institute P.O. Box 750 Sentrum 0106 Oslo Norway
| | - Craig J. Forsyth
- Department of Chemistry and BiochemistryThe Ohio State University 151 W. Woodruff Ave Columbus OH 43210 USA
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26
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Kenton NT, Adu‐Ampratwum D, Okumu AA, Zhang Z, Chen Y, Nguyen S, Xu J, Ding Y, McCarron P, Kilcoyne J, Rise F, Wilkins AL, Miles CO, Forsyth CJ. Total Synthesis of (6
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)‐Azaspiracid‐3 Reveals Non‐Identity with the Natural Product. Angew Chem Int Ed Engl 2017. [DOI: 10.1002/ange.201711006] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Affiliation(s)
- Nathaniel T. Kenton
- Department of Chemistry and BiochemistryThe Ohio State University 151 W. Woodruff Ave Columbus OH 43210 USA
| | - Daniel Adu‐Ampratwum
- Department of Chemistry and BiochemistryThe Ohio State University 151 W. Woodruff Ave Columbus OH 43210 USA
| | - Antony A. Okumu
- Department of Chemistry and BiochemistryThe Ohio State University 151 W. Woodruff Ave Columbus OH 43210 USA
| | - Zhigao Zhang
- Shanghai Hengrui Pharmaceutical Inc. No. 279 Wenjing Road Shanghai 200245 P. R. China
| | - Yong Chen
- Asymchem Life Science No. 71 7th Ave., TEDA Tianjin 300000 P. R. China
| | - Son Nguyen
- Johnson Matthey Pharma Services 25 Patton Road Devens MA 01434 USA
| | - Jianyan Xu
- Shanghai Hengrui Pharmaceutical Inc. No. 279 Wenjing Road Shanghai 200245 P. R. China
| | - Yue Ding
- Viva Biotech Ltd. 581 Shenkuo Rd., Pudong District Shanghai 201203 China
| | - Pearse McCarron
- Measurement Science and StandardsNational Research Council of Canada Halifax Nova Scotia B3H 3Z1 Canada
| | - Jane Kilcoyne
- Marine Institute, RinvilleOranmore, Co. Galway Ireland
| | - Frode Rise
- Department of ChemistryUniversity of Oslo 0315 Oslo Norway
| | - Alistair L. Wilkins
- Norwegian Veterinary Institute P.O. Box 750 Sentrum 0106 Oslo Norway
- Chemistry DepartmentUniversity of Waikato Private Bag 3105 3240 Hamilton New Zealand
| | - Christopher O. Miles
- Measurement Science and StandardsNational Research Council of Canada Halifax Nova Scotia B3H 3Z1 Canada
- Norwegian Veterinary Institute P.O. Box 750 Sentrum 0106 Oslo Norway
| | - Craig J. Forsyth
- Department of Chemistry and BiochemistryThe Ohio State University 151 W. Woodruff Ave Columbus OH 43210 USA
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27
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Zendong Z, Sibat M, Herrenknecht C, Hess P, McCarron P. Relative molar response of lipophilic marine algal toxins in liquid chromatography/electrospray ionization mass spectrometry. RAPID COMMUNICATIONS IN MASS SPECTROMETRY : RCM 2017; 31:1453-1461. [PMID: 28582796 DOI: 10.1002/rcm.7918] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/17/2017] [Revised: 06/01/2017] [Accepted: 06/01/2017] [Indexed: 06/07/2023]
Abstract
RATIONALE Accurate quantitative analysis of lipophilic toxins by liquid chromatography/mass spectrometry (LC/MS) requires calibration solution reference materials (RMs) for individual toxin analogs. Untargeted analysis is aimed at identifying a vast number of compounds and thus validation of fully quantitative untargeted methods is not feasible. However, a semi-quantitative approach allowing for profiling is still required and will be strengthened by knowledge of the relative molar response (RMR) of analogs in LC/MS with electrospray ionization (ESI). METHODS RMR factors were evaluated for toxins from the okadaic acid (OA/DTXs), yessotoxin (YTX), pectenotoxin (PTX), azaspiracid (AZA) and cyclic imine (CI) toxin groups, in both solvent standards and environmental sample extracts. Since compound ionization and fragmentation influences the MS response of toxins, RMRs were assessed under different chromatographic conditions (gradient, isocratic) and MS acquisition modes (SIM, SRM, All-ion, target MS/MS) on low- and high-resolution mass spectrometers. RESULTS In general, RMRs were not significantly impacted by chromatographic conditions (isocratic vs gradient), with the exception of DTX1. MS acquisition modes had a more significant impact, with PnTX-G and SPX differing notably. For a given toxin group, response factors were generally in the range of 0.5 to 2. The cyclic imines were an exception. CONCLUSIONS Differences in RMRs between toxins of a same chemical base structure were not significant enough to indicate major issues for non-targeted semi-quantitative analysis, where there is limited or no availability of standards for many compounds, and where high degrees of accuracy are not required. Differences in RMRs should be considered when developing methods that use a standard of a single analogue to quantitate other toxins from the same group.
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Affiliation(s)
- Zita Zendong
- Ifremer, Laboratoire Phycotoxines, Nantes, France
| | | | | | - Philipp Hess
- Ifremer, Laboratoire Phycotoxines, Nantes, France
| | - Pearse McCarron
- Measurement Science and Standards, National Research Council Canada, Halifax, NS, Canada
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28
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Kim JH, Tillmann U, Adams NG, Krock B, Stutts WL, Deeds JR, Han MS, Trainer VL. Identification of Azadinium species and a new azaspiracid from Azadinium poporum in Puget Sound, Washington State, USA. HARMFUL ALGAE 2017; 68:152-167. [PMID: 28962976 DOI: 10.1016/j.hal.2017.08.004] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/25/2017] [Revised: 08/07/2017] [Accepted: 08/07/2017] [Indexed: 06/07/2023]
Abstract
The identification of a new suite of toxins, called azaspiracids (AZA), as the cause of human illnesses after the consumption of shellfish from the Irish west coast in 1995, resulted in interest in understanding the global distribution of these toxins and of species of the small dinoflagellate genus Azadinium, known to produce them. Clonal isolates of four species of Azadinium, A. poporum, A. cuneatum, A. obesum and A. dalianense were obtained from incubated sediment samples collected from Puget Sound, Washington State in 2016. These Azadinium species were identified using morphological characteristics confirmed by molecular phylogeny. Whereas AZA could not be detected in any strains of A. obesum, A. cuneatum and A. dalianense, all four strains of A. poporum produced a new azaspiracid toxin, based on LC-MS analysis, named AZA-59. The presence of AZA-59 was confirmed at low levels in situ using a solid phase resin deployed at several stations along the coastlines of Puget Sound. Using a combination of molecular methods for species detection and solid phase resin deployment to target shellfish monitoring of toxin at high-risk sites, the risk of azaspiracid shellfish poisoning can be minimized.
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Affiliation(s)
- Joo-Hwan Kim
- Department of Life Science, College of Natural Sciences, Hanyang University, Seoul 04763, South Korea
| | - Urban Tillmann
- Alfred Wegener Institute, Helmholtz Center for Polar and Marine Research, Am Handelshafen 12, D-27570 Bremerhaven, Germany
| | - Nicolaus G Adams
- Northwest Fisheries Science Center, National Marine Fisheries Service, National Oceanic and Atmospheric Administration, 2725 Montlake Blvd. E., Seattle, WA 98112, USA
| | - Bernd Krock
- Alfred Wegener Institute, Helmholtz Center for Polar and Marine Research, Am Handelshafen 12, D-27570 Bremerhaven, Germany
| | - Whitney L Stutts
- United States Food and Drug Administration, Center for Food Safety and Applied Nutrition, 5001 Campus Drive, College Park, MD 20740, USA
| | - Jonathan R Deeds
- United States Food and Drug Administration, Center for Food Safety and Applied Nutrition, 5001 Campus Drive, College Park, MD 20740, USA
| | - Myung-Soo Han
- Department of Life Science, College of Natural Sciences, Hanyang University, Seoul 04763, South Korea.
| | - Vera L Trainer
- Northwest Fisheries Science Center, National Marine Fisheries Service, National Oceanic and Atmospheric Administration, 2725 Montlake Blvd. E., Seattle, WA 98112, USA.
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29
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Marine Toxins Analysis for Consumer Protection. RECENT ADVANCES IN THE ANALYSIS OF MARINE TOXINS 2017. [DOI: 10.1016/bs.coac.2017.07.004] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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Rossi R, Dell'Aversano C, Krock B, Ciminiello P, Percopo I, Tillmann U, Soprano V, Zingone A. Mediterranean Azadinium dexteroporum (Dinophyceae) produces six novel azaspiracids and azaspiracid-35: a structural study by a multi-platform mass spectrometry approach. Anal Bioanal Chem 2016; 409:1121-1134. [PMID: 27822651 DOI: 10.1007/s00216-016-0037-4] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2016] [Revised: 10/11/2016] [Accepted: 10/17/2016] [Indexed: 10/20/2022]
Abstract
Azadinium dexteroporum is the first species of the genus described from the Mediterranean Sea and it produces different azaspiracids (AZA). The aims of this work were to characterize the toxin profile of the species and gain structural information on azaspiracids produced by the A. dexteroporum strain SZN-B848 isolated from the Gulf of Naples. Liquid chromatography-mass spectrometry (LC-MS) analyses were carried out on three MS systems having different ion source geometries (ESI, TurboIonSpray®, ESI ION MAX) and different MS analyzers operating either at unit resolution or at high resolution, namely a hybrid triple quadrupole-linear ion trap (Q-Trap MS), a time of flight (TOF MS), and a hybrid linear ion trap Orbitrap XL Fourier transform mass spectrometer (LTQ Orbitrap XL FTMS). As a combined result of these different analyses, A. dexteroporum showed to produce AZA-35, previously reported from Azadinium spinosum, and six compounds that represent new additions to the AZA-group of toxins, including AZA-54 to AZA-58 and 3-epiAZA-7, a stereoisomer of the shellfish metabolite AZA-7. Based on the interpretation of fragmentation patterns, we propose that all these molecules, except AZA-55, have the same A to I ring system as AZA-1, with structural modifications all located in the carboxylic side chain. Considering that none of the azaspiracids produced by the Mediterranean strain of A. dexteroporum is currently regulated by European food safety authorities, monitoring programs of marine biotoxins in the Mediterranean area should take into account the occurrence of the new analogues to avoid an underestimation of the AZA-related risk for seafood consumers. Graphical Abstract A multi-platform MS approach reveals known and new azaspiracids in a Mediterranean strain of Azadinium dexteroporum.
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Affiliation(s)
- Rachele Rossi
- Istituto Zooprofilattico Sperimentale del Mezzogiorno, Via Salute 2, 80055, Portici, Italy
| | - Carmela Dell'Aversano
- Department of Pharmacy, University of Napoli Federico II, Via D. Montesano 49, 80131, Napoli, Italy.
| | - Bernd Krock
- Alfred-Wegener-Institut, Helmholtz-Zentrum für Polar- und Meeresforschung, Am Handelshafen 12, 27570, Bremerhaven, Germany
| | - Patrizia Ciminiello
- Department of Pharmacy, University of Napoli Federico II, Via D. Montesano 49, 80131, Napoli, Italy
| | - Isabella Percopo
- Department of Integrative Marine Ecology, Stazione Zoologica Anton Dohrn, Villa Comunale, 80121, Napoli, Italy
| | - Urban Tillmann
- Alfred-Wegener-Institut, Helmholtz-Zentrum für Polar- und Meeresforschung, Am Handelshafen 12, 27570, Bremerhaven, Germany
| | - Vittorio Soprano
- Istituto Zooprofilattico Sperimentale del Mezzogiorno, Via Salute 2, 80055, Portici, Italy
| | - Adriana Zingone
- Department of Integrative Marine Ecology, Stazione Zoologica Anton Dohrn, Villa Comunale, 80121, Napoli, Italy.
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Abstract
This review covers the literature published in 2014 for marine natural products (MNPs), with 1116 citations (753 for the period January to December 2014) referring to compounds isolated from marine microorganisms and phytoplankton, green, brown and red algae, sponges, cnidarians, bryozoans, molluscs, tunicates, echinoderms, mangroves and other intertidal plants and microorganisms. The emphasis is on new compounds (1378 in 456 papers for 2014), together with the relevant biological activities, source organisms and country of origin. Reviews, biosynthetic studies, first syntheses, and syntheses that lead to the revision of structures or stereochemistries, have been included.
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Affiliation(s)
- John W Blunt
- Department of Chemistry, University of Canterbury, Christchurch, New Zealand.
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32
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Kilcoyne J, McCarron P, Hess P, Miles CO. Effects of Heating on Proportions of Azaspiracids 1-10 in Mussels (Mytilus edulis) and Identification of Carboxylated Precursors for Azaspiracids 5, 10, 13, and 15. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2015; 63:10980-10987. [PMID: 26631586 DOI: 10.1021/acs.jafc.5b04609] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Azaspiracids (AZAs) are marine biotoxins that induce human illness following the consumption of contaminated shellfish. European Union regulation stipulates that only raw shellfish are tested, yet shellfish are often cooked prior to consumption. Analysis of raw and heat-treated mussels (Mytilus edulis) naturally contaminated with AZAs revealed significant differences (up to 4.6-fold) in AZA1-3 (1-3) and 6 (6) values due to heat-induced chemical conversions. Consistent with previous studies, high levels of 3 and 6 were detected in some samples that were otherwise below the limit of quantitation before heating. Relative to 1, in heat-treated mussels the average (n = 40) levels of 3 (range, 11-502%) and 6 (range, 3-170%) were 62 and 31%, respectively. AZA4 (4) (range, <1-27%), AZA5 (5) (range, 1-21%), and AZA8 (8) (range, 1-27%) were each ∼5%, whereas AZA7 (7), AZA9 (9), and AZA10 (10) (range, <1-8%) were each under 1.5%. Levels of 5, 10, AZA13 (13), and AZA15 (15) increased after heating, leading to the identification of novel carboxylated AZA precursors in raw shellfish extracts, which were shown by deuterium labeling to be precursors for 5, 10, 13, and 15.
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Affiliation(s)
- Jane Kilcoyne
- Marine Institute , Rinville, Oranmore, Co. Galway, Ireland
| | - Pearse McCarron
- Measurement Science and Standards, National Research Council Canada , Halifax, Nova Scotia B3H 3Z1, Canada
| | - Philipp Hess
- Laboratoire Phycotoxines, Ifremer , Rue de l'Ile d'Yeu, 44311 Nantes, France
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Krock B, Tillmann U, Potvin É, Jeong HJ, Drebing W, Kilcoyne J, Al-Jorani A, Twiner MJ, Göthel Q, Köck M. Structure Elucidation and in Vitro Toxicity of New Azaspiracids Isolated from the Marine Dinoflagellate Azadinium poporum. Mar Drugs 2015; 13:6687-702. [PMID: 26528990 PMCID: PMC4663548 DOI: 10.3390/md13116687] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2015] [Revised: 06/14/2015] [Accepted: 10/14/2015] [Indexed: 11/23/2022] Open
Abstract
Two strains of Azadinium poporum, one from the Korean West coast and the other from the North Sea, were mass cultured for isolation of new azaspiracids. Approximately 0.9 mg of pure AZA-36 (1) and 1.3 mg of pure AZA-37 (2) were isolated from the Korean (870 L) and North Sea (120 L) strains, respectively. The structures were determined to be 3-hydroxy-8-methyl-39-demethyl-azaspiracid-1 (1) and 3-hydroxy-7,8-dihydro-39-demethyl-azaspiracid-1 (2) by ¹H- and (13)C-NMR. Using the Jurkat T lymphocyte cell toxicity assay, (1) and (2) were found to be 6- and 3-fold less toxic than AZA-1, respectively.
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Affiliation(s)
- Bernd Krock
- Alfred-Wegener-Institut, Helmholtz-Zentrum für Polar- und Meeresforschung, Am Handelshafen 12, Bremerhaven 27570, Germany; E-Mails: (U.T.); (W.D.); (Q.G.)
| | - Urban Tillmann
- Alfred-Wegener-Institut, Helmholtz-Zentrum für Polar- und Meeresforschung, Am Handelshafen 12, Bremerhaven 27570, Germany; E-Mails: (U.T.); (W.D.); (Q.G.)
| | - Éric Potvin
- Division of Polar Ocean Environment, Korea Polar Research Institute, Incheon 406-840, Korea; E-Mail:
| | - Hae Jin Jeong
- School of Earth and Environmental Science, Seoul National University, Seoul 151-747, Korea; E-Mail:
| | - Wolfgang Drebing
- Alfred-Wegener-Institut, Helmholtz-Zentrum für Polar- und Meeresforschung, Am Handelshafen 12, Bremerhaven 27570, Germany; E-Mails: (U.T.); (W.D.); (Q.G.)
| | - Jane Kilcoyne
- Marine Institute, Rinville, Oranmore, Co. Galway, H91 R673, Ireland; E-Mail:
| | - Ahmed Al-Jorani
- Department of Natural Sciences, University of Michigan, Dearborn, MI 48202, USA; E-Mails: (A.A.-J.); (M.J.T.)
| | - Michael J. Twiner
- Department of Natural Sciences, University of Michigan, Dearborn, MI 48202, USA; E-Mails: (A.A.-J.); (M.J.T.)
| | - Qun Göthel
- Alfred-Wegener-Institut, Helmholtz-Zentrum für Polar- und Meeresforschung, Am Handelshafen 12, Bremerhaven 27570, Germany; E-Mails: (U.T.); (W.D.); (Q.G.)
| | - Matthias Köck
- Alfred-Wegener-Institut, Helmholtz-Zentrum für Polar- und Meeresforschung, Am Handelshafen 12, Bremerhaven 27570, Germany; E-Mails: (U.T.); (W.D.); (Q.G.)
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Samdal IA, Løvberg KE, Briggs LR, Kilcoyne J, Xu J, Forsyth CJ, Miles CO. Development of an ELISA for the Detection of Azaspiracids. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2015; 63:7855-7861. [PMID: 26245830 DOI: 10.1021/acs.jafc.5b02513] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Azaspiracids (AZAs) are a group of biotoxins that cause food poisoning in humans. These toxins are produced by small marine dinoflagellates such as Azadinium spinosum and accumulate in shellfish. Ovine polyclonal antibodies were produced and used to develop an ELISA for quantitating AZAs in shellfish, algal cells, and culture supernatants. Immunizing antigens were prepared from synthetic fragments of the constant region of AZAs, while plate coating antigen was prepared from AZA-1. The ELISA provides a sensitive and rapid analytical method for screening large numbers of samples. It has a working range of 0.45-8.6 ng/mL and a limit of quantitation for total AZAs in whole shellfish at 57 μg/kg, well below the maximum permitted level set by the European Commission. The ELISA has good cross-reactivity to AZA-1-10, -33, and -34 and 37-epi-AZA-1. Naturally contaminated Irish mussels gave similar results whether they were cooked or uncooked, indicating that the ELISA also detects 22-carboxy-AZA metabolites (e.g., AZA-17 and AZA-19). ELISA results showed excellent correlation with LC-MS/MS analysis, both for mussel extract spiked with AZA-1 and for naturally contaminated Irish mussels. The assay is therefore well suited to screening for AZAs in shellfish samples intended for human consumption, as well as for studies on AZA metabolism.
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Affiliation(s)
- Ingunn A Samdal
- Norwegian Veterinary Institute, P.O. Box 750 Sentrum, N-0106 Oslo, Norway
| | - Kjersti E Løvberg
- Norwegian Veterinary Institute, P.O. Box 750 Sentrum, N-0106 Oslo, Norway
| | - Lyn R Briggs
- AgResearch, Ruakura, East Street, Private Bag 3123, Hamilton, New Zealand
| | - Jane Kilcoyne
- Marine Institute , Rinville, Oranmore, County Galway, Ireland
| | - Jianyan Xu
- Department of Chemistry, University of Minnesota-Twin Cities , Minneapolis, Minnesota 55455, United States
| | - Craig J Forsyth
- Department of Chemistry and Biochemistry, The Ohio State University , Columbus, Ohio 43210, United States
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Kilcoyne J, Twiner MJ, McCarron P, Crain S, Giddings SD, Foley B, Rise F, Hess P, Wilkins AL, Miles CO. Structure Elucidation, Relative LC-MS Response and In Vitro Toxicity of Azaspiracids 7-10 Isolated from Mussels (Mytilus edulis). JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2015; 63:5083-5091. [PMID: 25909151 DOI: 10.1021/acs.jafc.5b01320] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Azaspiracids (AZAs) are marine biotoxins produced by dinoflagellates that can accumulate in shellfish, which if consumed can lead to poisoning events. AZA7-10, 7-10, were isolated from shellfish and their structures, previously proposed on the basis of only LC-MS/MS data, were confirmed by NMR spectroscopy. Purified AZA4-6, 4-6, and 7-10 were accurately quantitated by qNMR and used to assay cytotoxicity with Jurkat T lymphocyte cells for the first time. LC-MS(MS) molar response studies performed using isocratic and gradient elution in both selected ion monitoring and selected reaction monitoring modes showed that responses for the analogues ranged from 0.3 to 1.2 relative to AZA1, 1. All AZA analogues tested were cytotoxic to Jurkat T lymphocyte cells in a time- and concentration-dependent manner; however, there were distinct differences in their EC50 values, with the potencies for each analogue being: AZA6 > AZA8 > AZA1 > AZA4 ≈ AZA9 > AZA5 ≈ AZA10. This data contributes to the understanding of the structure-activity relationships of AZAs.
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Affiliation(s)
- Jane Kilcoyne
- †Marine Institute, Rinville, Oranmore, County Galway, Ireland
- ‡School of Chemical and Pharmaceutical Sciences, Dublin Institute of Technology, Kevin Street, Dublin 8, Ireland
| | - Michael J Twiner
- §School of Medicine, Wayne State University, Detroit, Michigan 48202, United States
| | - Pearse McCarron
- ⊥Measurement Science and Standards, Biotoxin Metrology, National Research Council Canada, 1411 Oxford Street, Halifax, Nova Scotia B3H 3Z1, Canada
| | - Sheila Crain
- ⊥Measurement Science and Standards, Biotoxin Metrology, National Research Council Canada, 1411 Oxford Street, Halifax, Nova Scotia B3H 3Z1, Canada
| | - Sabrina D Giddings
- ⊥Measurement Science and Standards, Biotoxin Metrology, National Research Council Canada, 1411 Oxford Street, Halifax, Nova Scotia B3H 3Z1, Canada
| | - Barry Foley
- ‡School of Chemical and Pharmaceutical Sciences, Dublin Institute of Technology, Kevin Street, Dublin 8, Ireland
| | - Frode Rise
- ∥Department of Chemistry, University of Oslo, N-0315 Oslo, Norway
| | - Philipp Hess
- ▽Ifremer, Laboratoire Phycotoxines, Rue de l'Ile d'Yeu, 44311 Nantes, France
| | | | - Christopher O Miles
- ○Norwegian Veterinary Institute, P.O. Box 750 Sentrum, 0106 Oslo Norway
- #Department of Pharmaceutical Chemistry, School of Pharmacy, University of Oslo, P.O. Box 1068 Blindern, N-0316 Oslo Norway
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