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Registros recuperados: 11 | |
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Mccarron, Pearse; Giddings, Sabrina D.; Reeves, Kelley L.; Hess, Philipp; Quilliam, Michael A.. |
Azaspiracids (AZAs) are lipophilic biotoxins produced by marine algae that can contaminate shellfish and cause human illness. The European Union (EU) regulates the level of AZAs in shellfish destined for the commercial market, with liquid chromatography-mass spectrometry (LC-MS) being used as the official reference method for regulatory analysis. Certified reference materials (CRMs) are essential tools for the development, validation, and quality control of LC-MS methods. This paper describes the work that went into the planning, preparation, characterization, and certification of CRM-AZA-Mus, a tissue matrix CRM, which was prepared as a wet homogenate from mussels (Mytilus edulis) naturally contaminated with AZAs. The homogeneity and stability of... |
Tipo: Text |
Palavras-chave: Azaspiracids; Seafood safety; Matrix certified reference material; Liquid chromatography-mass spectrometry; Matrix effects. |
Ano: 2015 |
URL: http://archimer.ifremer.fr/doc/00320/43138/42761.pdf |
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Kilcoyne, Jane; Nulty, Ciara; Jauffrais, Thierry; Mccarron, Pearse; Herve, Fabienne; Foley, Barry; Rise, Frode; Crain, Sheila; Wilkins, Alistair L.; Twiner, Michael J.; Hess, Philipp; Miles, Christopher O.. |
We identified three new azaspiracids (AZAs) with molecular weights of 715, 815, and 829 (AZA33 (3), AZA34 (4), and AZA35, respectively) in mussels, seawater, and Azadinium spinosum culture. Approximately 700 mu g of 3 and 250 mu g of 4 were isolated from a bulk culture of A. spinosum, and their structures determined by MS and NMR spectroscopy. These compounds differ significantly at the carboxyl end of the molecule from known AZA analogues and therefore provide valuable information on structure-activity relationships. Initial toxicological assessment was performed using an in vitro model system based on Jurkat T lymphocyte cytotoxicity, and the potencies of 3 and 4 were found to be 0.22- and 5.5-fold that of AZA1 (1), respectively. Thus, major changes in... |
Tipo: Text |
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Ano: 2014 |
URL: https://archimer.ifremer.fr/doc/00245/35606/34414.pdf |
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Zendong, Suzie Zita; Mccarron, Pearse; Herrenknecht, Christine; Sibat, Manoella; Amzil, Zouher; Cole, Richard B.; Hess, Philipp. |
Measurement of marine algal toxins has traditionally focussed on shellfish monitoring while, over the last decade, passive sampling has been introduced as a complementary tool for exploratory studies. Since 2011, liquid chromatography-tandem mass spectrometry (LC-MS/MS) has been adopted as the EU reference method (No.15/2011) for detection and quantitation of lipophilic toxins. Traditional LC-MS approaches have been based on low-resolution mass spectrometry (LRMS), however, advances in instrument platforms have led to a heightened interest in the use of high-resolution mass spectrometry (HRMS) for toxin detection. This work describes the use of HRMS in combination with passive sampling as a progressive approach to marine algal toxin surveys. Experiments... |
Tipo: Text |
Palavras-chave: Monitoring; Marine toxins; Passive sampling; SPATT; Matrix effects. |
Ano: 2015 |
URL: http://archimer.ifremer.fr/doc/00277/38848/37388.pdf |
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Zendong, Suzie Zita; Sibat, Manoella; Herrenknecht, Christine; Hess, Philipp; Mccarron, Pearse. |
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 liquid chromatography-mass spectrometry (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... |
Tipo: Text |
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Ano: 2017 |
URL: http://archimer.ifremer.fr/doc/00387/49877/50434.pdf |
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Mccarron, Pearse; Emteborg, Hakan; Nulty, Ciara; Rundberget, Thomas; Loader, Jared I.; Teipel, Katharina; Miles, Christopher O.; Quilliam, Michael A.; Hess, Philipp. |
The development of multi-analyte methods for lipophilic shellfish toxins based on liquid chromatography-mass spectrometry permits rapid screening and analysis of samples for a wide variety of toxins in a single run. Validated methods and appropriate certified reference materials (CRMs) are required to ensure accuracy of results. CRMs are essential for accurate instrument calibration, for assessing the complete analytical method from sample extraction to data analysis and for verifying trueness. However, CRMs have hitherto only been available for single toxin groups. Production of a CRM containing six major toxin groups was achieved through an international collaboration. Preparation of this material, CRM-FDMT1, drew on information from earlier studies as... |
Tipo: Text |
Palavras-chave: CRM-FDMT1; Certified reference material; Shellfish toxins; Phycotoxins; Accuracy; Precision; Liquid chromatography-mass spectrometry. |
Ano: 2011 |
URL: http://archimer.ifremer.fr/doc/00037/14826/12237.pdf |
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Kilcoyne, Jane; Twiner, Michael J.; Mccarron, Pearse; Crain, Sheila; Giddings, Sabrina D.; Foley, Barry; Rise, Frode; Hess, Philipp; Willdns, Alistair L.; Miles, Christopher O.. |
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... |
Tipo: Text |
Palavras-chave: Azaspiracid; Structure confirmation; LC-MS molar response; NMR; Mass spectrometry; Purification; Jurkat T; Toxicity. |
Ano: 2015 |
URL: http://archimer.ifremer.fr/doc/00269/38059/36190.pdf |
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Ji, Ying; Che, Yijia; Wright, Elliott J.; Mccarron, Pearse; Hess, Philipp; Li, Aifeng. |
Marine shellfish exposed to the microalgae Karenia selliformis can accumulate gymnodimines (GYM). Shellfish samples collected from Beihai City in Guangxi Autonomous Region, and Ningde City in Fujian Province, in the South China Sea, as well as mussels Mytilus galloprovincialis fed on K. selliformis under laboratory conditions were analyzed. Gymnodimines and various fatty acid ester metabolites were detected in the clam Antigona lamellaris and pen shell Atrina pectinata, while no esters were found in the oyster Crassostrea sp. and the gastropod Batillaria zonalis despite positive detection of free GYM in both species. When present, the predominant acyl esters observed were 18:0-GYM-A and 20:1-GYM-A. Under laboratory conditions GYM-A was accumulated and... |
Tipo: Text |
Palavras-chave: Gymnodimines (GYM); Fatty acid ester; Karenia selliformis; Toxin profiles; Antioxidant enzymes. |
Ano: 2020 |
URL: https://archimer.ifremer.fr/doc/00609/72153/73203.pdf |
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Jauffrais, Thierry; Herrenknecht, Christine; Sechet, Veronique; Sibat, Manoella; Tillmann, Urban; Krock, Bernd; Kilcoyne, Jane; Miles, Christopher O.; Mccarron, Pearse; Amzil, Zouher; Hess, Philipp. |
Azaspiracids (AZAs) are secondary metabolites of Azadinium spinosum, that have been shown to cause diarrhetic shellfish poisoning when accumulated in bivalve molluscs. We describe here an analytical procedure for the determination of AZAs in cultures of A. spinosum with a focus on the potential formation of AZA methyl-esters as artefacts in the extraction and sample pre-treatment. A. spinosum cells were collected from bioreactor cultures, using centrifugation or filtration. Different extraction procedures were evaluated for formation of methyl-ester artefacts, yield, and matrix effects. Filtration of cultures using glass-fibre filters led to increased formation of methyl-esters. Hence centrifugation is recommended for recovery of cells. The type of... |
Tipo: Text |
Palavras-chave: Extraction procedure; Extraction artefact; Matrix effects; LC-MS/MS; Azaspiracid methyl ester; Dinoflagellate; Liquid chromatography-mass spectrometry. |
Ano: 2012 |
URL: http://archimer.ifremer.fr/doc/00077/18812/16463.pdf |
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Kilcoyne, Jane; Mccarron, Pearse; Hess, Philipp; Miles, Christopher O.. |
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... |
Tipo: Text |
Palavras-chave: Azaspiracid; Decarboxylation; Hydroxylation; Chemical conversion; Heating mass spectrometry; Metabolism. |
Ano: 2015 |
URL: http://archimer.ifremer.fr/doc/00303/41433/41005.pdf |
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Kilcoyne, Jane; Mccarron, Pearse; Twiner, Michael J.; Rise, Frode; Hess, Philipp; Wilkins, Alistair L.; Miles, Christopher O.. |
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... |
Tipo: Text |
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Ano: 2018 |
URL: https://archimer.ifremer.fr/doc/00428/54001/55286.pdf |
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Kilcoyne, Jane; Mccarron, Pearse; Hess, Philipp; Miles, Christopher O.. |
This dataset is composed by the supporting information of Kilcoyne Jane, Mccarron Pearse, Hess Philipp, Miles Christopher O. (2015). 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, 63(51), 10980-10987. http://dx.doi.org/10.1021/acs.jafc.5b04609 |
Tipo: Dataset |
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Ano: 2015 |
URL: http://dx.doi.org/10.17882/41845 |
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Registros recuperados: 11 | |
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