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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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Oliveira CYB, Abreu JL, Santos EP, Matos ÂP, Tribuzi G, Oliveira CDL, Veras BO, Bezerra RS, Müller MN, Gálvez AO. Light induces peridinin and docosahexaenoic acid accumulation in the dinoflagellate Durusdinium glynnii. Appl Microbiol Biotechnol 2022; 106:6263-6276. [PMID: 35972515 DOI: 10.1007/s00253-022-12131-6] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2022] [Revised: 08/02/2022] [Accepted: 08/03/2022] [Indexed: 11/02/2022]
Abstract
Peridinin is a light-harvesting carotenoid present in phototrophic dinoflagellates and has great potential for new drug applications and cosmetics development. Herein, the effects of irradiance mediated by light-emitting diodes on growth performance, carotenoid and fatty acid profiles, and antioxidant activity of the endosymbiotic dinoflagellate Durusdinium glynnii were investigated. The results demonstrate that D. glynnii is particularly well adapted to low-light conditions; however, it can be high-light-tolerant. In contrast to other light-harvesting carotenoids, the peridinin accumulation in D. glynnii occurred during high-light exposure. The peridinin to chlorophyll-a ratio varied as a function of irradiance, while the peridinin to total carotenoids ratio remained stable. Under optimal irradiance for growth, there was a peak in docosahexaenoic acid (DHA) bioaccumulation. This study contributes to the understanding of the photoprotective role of peridinin in endosymbiont dinoflagellates and highlights the antioxidant activity of peridinin-rich extracts. KEY POINTS: • Peridinin has a protective role against chlorophyll photo-oxidation • High light conditions induce cellular peridinin accumulation • D. glynnii accumulates high amounts of DHA under optimal light supply.
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Affiliation(s)
- Carlos Yure B Oliveira
- Department of Fishing and Aquaculture, Federal Rural University of Pernambuco, St. Dom Manuel de Medeiros, Dois Irmãos, Recife, 52171-900, Brazil.
| | - Jéssika L Abreu
- Department of Fishing and Aquaculture, Federal Rural University of Pernambuco, St. Dom Manuel de Medeiros, Dois Irmãos, Recife, 52171-900, Brazil
| | - Elizabeth P Santos
- Department of Fishing and Aquaculture, Federal Rural University of Pernambuco, St. Dom Manuel de Medeiros, Dois Irmãos, Recife, 52171-900, Brazil
| | - Ângelo P Matos
- Center of Agricultural Sciences, Federal University of Santa Catarina, Florianópolis, 88034-001, Brazil
| | - Giustino Tribuzi
- Department of Food Science and Technology, Federal University of Santa Catarina, Florianopolis, 88034-801, Brazil
| | - Cicero Diogo L Oliveira
- Institute of Biological Sciences and Health, Federal University of Alagoas, Maceio, 57072-900, Brazil
| | - Bruno O Veras
- Department of Biochemistry, Federal University of Pernambuco, Recife, 50740-550, Brazil
| | - Railson S Bezerra
- Department of Biochemistry, Federal University of Pernambuco, Recife, 50740-550, Brazil
| | - Marius N Müller
- Department of Oceanography, Federal University of Pernambuco, Recife, 50740-550, Brazil
| | - Alfredo O Gálvez
- Department of Fishing and Aquaculture, Federal Rural University of Pernambuco, St. Dom Manuel de Medeiros, Dois Irmãos, Recife, 52171-900, Brazil
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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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Otero P, Silva M. Emerging Marine Biotoxins in European Waters: Potential Risks and Analytical Challenges. Mar Drugs 2022; 20:199. [PMID: 35323498 PMCID: PMC8955394 DOI: 10.3390/md20030199] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2022] [Revised: 02/15/2022] [Accepted: 03/05/2022] [Indexed: 01/21/2023] Open
Abstract
Harmful algal blooms pose a challenge regarding food safety due to their erratic nature and forming circumstances which are yet to be disclosed. The best strategy to protect human consumers is through legislation and monitoring strategies. Global warming and anthropological intervention aided the migration and establishment of emerging toxin producers into Europe's temperate waters, creating a new threat to human public health. The lack of information, standards, and reference materials delay effective solutions, being a matter of urgent resolution. In this work, the recent findings of the presence of emerging azaspiracids, spirolildes, pinnatoxins, gymnodimines, palitoxins, ciguatoxins, brevetoxins, and tetrodotoxins on European Coasts are addressed. The information concerning emerging toxins such as new matrices, locations, and toxicity assays is paramount to set the risk assessment guidelines, regulatory levels, and analytical methodology that would protect the consumers.
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Affiliation(s)
- Paz Otero
- Department of Pharmacology, Pharmacy and Pharmaceutical Technology, Faculty of Veterinary Science, Universidade de Santiago de Compostela, 27002 Lugo, Spain
| | - Marisa Silva
- MARE—Marine and Environmental Sciences Centre, Faculty of Sciences, University of Lisbon, Campo Grande, 1749-016 Lisbon, Portugal
- Department of Plant Biology, Faculty of Sciences, University of Lisbon, Campo Grande, 1749-016 Lisbon, Portugal
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Assunção J, Amaro HM, Lopes G, Tavares T, Malcata FX, Guedes AC. Karlodinium veneficum: Growth optimization, metabolite characterization and biotechnological potential survey. J Appl Microbiol 2021; 132:2844-2858. [PMID: 34865282 DOI: 10.1111/jam.15403] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2021] [Revised: 07/23/2021] [Accepted: 11/28/2021] [Indexed: 11/26/2022]
Abstract
AIM OF THIS STUDY The major aim of this work was to consistently optimize the production of biomass of the dinoflagellate Karlodinium veneficum and evaluate its extracts biotechnological potential application towards food, nutraceutical or/and pharmaceutical industries. METHODS AND RESULTS A successful approach of biomass production of K. veneficum CCMP 2936 was optimized along with the chemical characterization of its metabolite profile. Several temperatures (12, 16, 20, 25, 30°C), L1 nutrient concentrations (0.5×, 2×, 2.5×, 3×) and NaCl concentrations (20, 25, 30, 40 g L-1 ) were tested. The growth rate was maximum at 16°C, 2× nutrient concentration and 40 g L-1 of NaCl; hence, these conditions were chosen for bulk production of biomass. Methanolic extracts were prepared, and pigments, lipids and phenolic compounds were assessed; complemented by antioxidant and anti-inflammatory capacities, and cytotoxicity. Fucoxanthin and derivatives accounted for 0.06% of dry weight, and up to 60% (w/w) of all quantified metabolites were lipids. Said extracts displayed high antioxidant capacity, as towards assessed via the NO•- and ABTS•+ assays (IC50 = 109.09 ± 6.73 and 266.46 ± 2.25 µgE ml-1 , respectively), unlike observed via the O2 •- assay (IC25 reaching 56.06 ± 5.56 µgE ml-1 ). No signs of cytotoxicity were observed. CONCLUSIONS Karlodinium veneficum biomass production was consistently optimized in terms of temperature, L1 nutrient concentrations and NaCl concentration. In addition, this strain appears promising for eventual biotechnological exploitation. SIGNIFICANCE AND IMPACT OF THE STUDY This work provides fundamental insights about the growth and potential of value-added compounds of dinoflagellate K. veneficum. Dinoflagellates, as K. veneficum are poorly studied regarding its biomass production and added-value compounds for potential biotechnological exploitation. These organisms are difficult to maintain and grow in the laboratory. Thus, any fundamental contribution is relevant to share with the scientific community.
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Affiliation(s)
- Joana Assunção
- CIIMAR - Interdisciplinary Centre of Marine and Environmental Research, Novo Edíficio do Terminal de Cruzeiros do Porto de Leixões, Matosinhos, Portugal.,LEPABE - Laboratory for Process Engineering, Environment, Biotechnology and Energy, University of Porto, Porto, Portugal
| | - Helena M Amaro
- CIIMAR - Interdisciplinary Centre of Marine and Environmental Research, Novo Edíficio do Terminal de Cruzeiros do Porto de Leixões, Matosinhos, Portugal
| | - Graciliana Lopes
- CIIMAR - Interdisciplinary Centre of Marine and Environmental Research, Novo Edíficio do Terminal de Cruzeiros do Porto de Leixões, Matosinhos, Portugal.,FCUP, Department of Biology, Faculty of Sciences, University of Porto, Porto, Portugal
| | - Tânia Tavares
- LEPABE - Laboratory for Process Engineering, Environment, Biotechnology and Energy, University of Porto, Porto, Portugal
| | - F Xavier Malcata
- LEPABE - Laboratory for Process Engineering, Environment, Biotechnology and Energy, University of Porto, Porto, Portugal.,FEUP - Faculty of Engineering of University of Porto, Porto, Portugal
| | - A Catarina Guedes
- CIIMAR - Interdisciplinary Centre of Marine and Environmental Research, Novo Edíficio do Terminal de Cruzeiros do Porto de Leixões, Matosinhos, Portugal
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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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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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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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Kilcoyne J, Burrell S, Nulty C, Salas R, Wright EJ, Rajotte I, Miles CO. Improved Isolation Procedures for Okadaic Acid Group Toxins from Shellfish ( Mytilus edulis) and Microalgae ( Prorocentrum lima). Mar Drugs 2020; 18:md18120647. [PMID: 33339248 PMCID: PMC7766028 DOI: 10.3390/md18120647] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2020] [Revised: 12/03/2020] [Accepted: 12/14/2020] [Indexed: 11/17/2022] Open
Abstract
Okadaic acid (OA) group toxins may accumulate in shellfish and can result in diarrhetic shellfish poisoning when consumed by humans, and are therefore regulated. Purified toxins are required for the production of certified reference materials used to accurately quantitate toxin levels in shellfish and water samples, and for other research purposes. An improved procedure was developed for the isolation of dinophysistoxin 2 (DTX2) from shellfish (M. edulis), reducing the number of purification steps from eight to five, thereby increasing recoveries to ~68%, compared to ~40% in a previously reported method, and a purity of >95%. Cell densities and toxin production were monitored in cultures of Prorocentrum lima, that produced OA, DTX1, and their esters, over ~1.5 years with maximum cell densities of ~70,000 cells mL−1 observed. Toxin accumulation progressively increased over the study period, to ~0.7 and 2.1 mg L−1 of OA and DTX1 (including their esters), respectively, providing information on appropriate harvesting times. A procedure for the purification of OA and DTX1 from the harvested biomass was developed employing four purification steps, with recoveries of ~76% and purities of >95% being achieved. Purities were confirmed by LC-HRMS, LC-UV, and NMR spectroscopy. Additional stability observations led to a better understanding of the chemistry of these toxins.
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Affiliation(s)
- Jane Kilcoyne
- Marine Institute, Rinville, Oranmore, Co. Galway H91 R673, Ireland; (S.B.); (C.N.); (R.S.)
- Correspondence: ; Tel.: +353-91387200
| | - Stephen Burrell
- Marine Institute, Rinville, Oranmore, Co. Galway H91 R673, Ireland; (S.B.); (C.N.); (R.S.)
| | - Cíara Nulty
- Marine Institute, Rinville, Oranmore, Co. Galway H91 R673, Ireland; (S.B.); (C.N.); (R.S.)
| | - Rafael Salas
- Marine Institute, Rinville, Oranmore, Co. Galway H91 R673, Ireland; (S.B.); (C.N.); (R.S.)
| | - Elliott J. Wright
- Biotoxin Metrology, National Research Council Canada, Halifax, NS B3H 3Z1, Canada; (E.J.W.); (I.R.); (C.O.M.)
| | - Isabelle Rajotte
- Biotoxin Metrology, National Research Council Canada, Halifax, NS B3H 3Z1, Canada; (E.J.W.); (I.R.); (C.O.M.)
| | - Christopher O. Miles
- Biotoxin Metrology, National Research Council Canada, Halifax, NS B3H 3Z1, Canada; (E.J.W.); (I.R.); (C.O.M.)
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Distribution and abundance of azaspiracid-producing dinophyte species and their toxins in North Atlantic and North Sea waters in summer 2018. PLoS One 2020; 15:e0235015. [PMID: 32559229 PMCID: PMC7304611 DOI: 10.1371/journal.pone.0235015] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2020] [Accepted: 06/05/2020] [Indexed: 12/11/2022] Open
Abstract
Representatives of the marine dinophyte family Amphidomataceae produce lipophilic phycotoxins called azaspiracids (AZA) which may cause azaspiracid shellfish poisoning (AZP) in humans after consumption of contaminated seafood. Three of the four known toxigenic species are observed frequently in the eastern North Atlantic. In 2018, a research survey was performed to strengthen knowledge on the distribution and abundance of toxigenic Amphidomataceae and their respective toxins in Irish coastal waters and in the North Sea. Species-specific quantification of the three toxigenic species (Azadinium spinosum, Azadinium poporum and Amphidoma languida) was based on recently developed qPCR assays, whose performance was successfully validated and tested with specificity tests and spike experiments. The multi-method approach of on-board live microscopy, qPCR assays and chemical AZA-analysis revealed the presence of Amphidomataceae in the North Atlantic including the three targeted toxigenic species and their respective AZA analogues (AZA-1, -2, -33, -38, -39). Azadinium spinosum was detected at the majority of Irish stations with a peak density of 8.3 x 104 cells L-1 and AZA (AZA-1, -2, -33) abundances up to 1,274 pg L-1. Amphidoma languida was also present at most Irish stations but appeared in highest abundance in a bloom at a central North Sea station with a density of 1.2 x 105 cells L-1 and an AZA (AZA-38, -39) abundances of 618 pg L-1. Azadinium poporum was detected sporadically at the Irish south coast and North Sea and was rather low in abundance during this study. The results confirmed the wide distribution and frequent occurrence of the target species in the North Atlantic area and revealed, for the first time, bloom abundances of toxigenic Amphidomataceae in this area. This emphasizes the importance of future studies and monitoring of amphidomatacean species and their respective AZA analogues in the North Atlantic.
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