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| Registros recuperados: 40 | |
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| Kerbrat, Anne Sophie; Amzil, Zouher; Pawlowiez, Ralph; Golubic, Stjepko; Sibat, Manoella; Darius, Helene Taiana; Chinain, Mireille; Laurent, Dominique. |
| Marine pelagic diazotrophic cyanobacteria of the genus Trichodesmium (Oscillatoriales) are widespread throughout the tropics and subtropics, and are particularly common in the waters of New Caledonia. Blooms of Trichodesmium are suspected to be a potential source of toxins in the ciguatera food chain and were previously reported to contain several types of paralyzing toxins. The toxicity of water-soluble extracts of Trichodesmium spp. were analyzed by mouse bioassay and Neuroblastoma assay and their toxic compounds characterized using liquid chromatography coupled with tandem mass spectrometry techniques. Here, we report the first identification of palytoxin and one of its derivatives, 42-hydroxy-palytoxin, in field samples of Trichodesmium collected in... |
| Tipo: Text |
Palavras-chave: Cyanobacteria; Trichodesmium; Palytoxin; 42-hydroxy-palytoxin; Clupeotoxism. |
| Ano: 2011 |
URL: https://archimer.ifremer.fr/doc/00040/15143/12576.pdf |
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| Amzil, Zouher; Sibat, Manoella; Royer, Florence; Masson, Nadine; Abadie, Eric. |
| In the context of the French Phytoplankton and Phycotoxins Monitoring Network (REPHY) programme, shellfish samples were harvested from different locations where harmful algae blooms were known to have occurred. For all shellfish samples found positive by the mouse bioassay for diarrhetic shellfish poisoning (DSP) toxins, liquid chromatography (LC) coupled with mass spectrometry (MS) was used to search for the following lipophilic toxins: okadaic acid (OA), dinophysistoxins (DTXs), pectenotoxins (PTXs), azaspiracids (AZAs), yessotoxins (YTXs), spirolides (SPXs) and gymnodimines (GYMs). In order to investigate the presence of acyl-OAs and/or acyl-DTX-1,-2 (DTX-3), alkaline hydrolysis was performed on all samples, and LC/ MS analyses were carried out on the... |
| Tipo: Text |
Palavras-chave: LC/MS analysis; Pectenotoxins; Spirolides; DSP toxins. |
| Ano: 2007 |
URL: http://archimer.ifremer.fr/doc/2007/publication-6206.pdf |
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| Laabir, Mohamed; Collos, Yves; Masseret, Estelle; Grzebyk, Daniel; Abadie, Eric; Savar, Veronique; Sibat, Manoella; Amzil, Zouher. |
| Laboratory experiments were designed to study the toxin content and profile of the Alexandrium catenella strain ACT03 (isolated from Thau Lagoon, French Mediterranean) in response to abiotic environmental factors under nutrient-replete conditions. This dinoflagellate can produce various paralytic shellfish toxins with concentrations ranging from 2.9 to 50.3 fmol/cell. The toxin profile was characterized by carbamate toxins (GTX3, GTX4 and GTX5) and N-sulfocarbamoyl toxins (C1, C2, C3 and C4). C2 dominated at 12-18 degrees C, but only for salinities ranging from 10 to 25 psu, whereas GTX5 became dominant at temperatures ranging from 21 to 30 degrees C at almost all salinities. There was no significant variation in the cellular toxin amount from 18 degrees C... |
| Tipo: Text |
Palavras-chave: Alexandrium catenella; PSP toxins; Temperature; Salinity; Light. |
| Ano: 2013 |
URL: http://archimer.ifremer.fr/doc/00148/25969/24056.pdf |
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| Briand, Enora; Reubrech, Sébastien; Mondeguer, Florence; Sibat, Manoella; Hess, Philipp; Amzil, Zouher; Bormans, Myriam. |
| Freshwater cyanobacteria are well known for their ability to produce a wide variety of bioactive compounds, some of which have been described as allelochemicals. There is growing evidence that these secondary metabolites play an important role in shaping community composition through biotic interactions; however, for the most part, their biological role and mode of regulation of the production are poorly understood. In temperate eutrophic freshwaters, Microcystis and Planktothrix often co-occur, with Planktothrix being an early colonizer and Microcystis appearing subsequently. We tested if the production of a range of peptides by co-existing species could be regulated through interspecific interactions. Using a combined approach of co-cultures and analyses... |
| Tipo: Text |
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| Ano: 2017 |
URL: http://archimer.ifremer.fr/doc/00374/48515/48794.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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| Darius, Ht; Viallon, J; Gatti, Cm; Chinain, M; Roué, M; Sibat, Manoella; Amzil, Zouher; Hess, Philipp; Vandersea, Mw; Litaker, Rw; Tester, Pa. |
| Tipo: Text |
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| Ano: 2018 |
URL: https://archimer.ifremer.fr/doc/00450/56181/57729.pdf |
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| Mondeguer, Florence; Souard, Florence; Guitton, Yann; Latimier, Marie; Quere, Julien; Sibat, Manoella; Hess, Philipp; Siano, Raffaele. |
| Aquatic ecosystems worldwide have been negatively affected by eutrophication, many of them driven by increasing nutrient inputs from untreated domestic sewage and industrial and agricultural wastewater. During their life cycle, Alexandrium minutum and Scrippsiella donghaienis can produce resistant and revivable cysts that can accumulate in the sediments of the coastal marine environment for hundreds of years. As a working hypothesis, we presumed that these two genera have preserved their adaptation to such ecosystem changes in the form of cysts in the old sediments. From revivified cysts, some cultures of toxic and non-toxic dinoflagellates (A. minutum and S. donghaienis) were analyzed by a untargeted metabolomics approach by LC-HRMS to study the possible... |
| Tipo: Text |
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| Ano: 2018 |
URL: https://archimer.ifremer.fr/doc/00440/55199/56664.pdf |
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| Darius, Helene Taiana; Roue, Melanie; Sibat, Manoella; Viallon, Jerome; Gatti, Clemence Mahana Iti; Vandersea, Mark W.; Tester, Patricia A.; Litaker, R. Wayne; Amzil, Zouher; Hess, Philipp; Chinain, Mireille. |
| The sea urchin Tripneustes gratilla (Toxopneustidae, Echinoids) is a source of protein for many islanders in the Indo-West Pacific. It was previously reported to occasionally cause ciguatera-like poisoning; however, the exact nature of the causative agent was not confirmed. In April and July 2015, ciguatera poisonings were reported following the consumption of T. gratilla in Anaho Bay (Nuku Hiva Island, Marquesas archipelago, French Polynesia). Patient symptomatology was recorded and sea urchin samples were collected from Anaho Bay in July 2015 and November 2016. Toxicity analysis using the neuroblastoma cell–based assay (CBA-N2a) detected the presence of ciguatoxins (CTXs) in T. gratilla samples. Gambierdiscus species were predominant in the benthic... |
| Tipo: Text |
Palavras-chave: Ciguatera poisoning; Ciguatoxins; Tripneustes gratilla; Sea urchin; Echinoidea; Gambierdiscus polynesiensis; Windowscreens; Artificial substrates; QPCR assays; CBA-N2a; LC-MS/MS. |
| Ano: 2018 |
URL: https://archimer.ifremer.fr/doc/00436/54716/56153.pdf |
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| Longo, Sébastien; Sibat, Manoella; Taiana Darius, Hélène; Hess, Philipp; Chinain, Mireille. |
| Ciguatera poisoning is a foodborne disease caused by the consumption of seafood contaminated with ciguatoxins (CTXs) produced by dinoflagellates in the genera Gambierdiscus and Fukuyoa. Ciguatera outbreaks are expected to increase worldwide with global change, in particular as a function of its main drivers, including changes in sea surface temperature, acidification, and coastal eutrophication. In French Polynesia, G. polynesiensis is regarded as the dominant source of CTXs entering the food web. The effects of pH (8.4, 8.2, and 7.9), Nitrogen:Phosphorus ratios (24N:1P vs. 48N:1P), and nitrogen source (nitrates vs. urea) on growth rate, biomass, CTX levels, and profiles were examined in four clones of G. polynesiensis at different culture age (D10, D21,... |
| Tipo: Text |
Palavras-chave: Gambierdiscus polynesiensis; French Polynesia; Ciguatera; Ciguatoxins; LC-MS; MS; Toxin profile; Nitrate; Urea; Culture medium acidification. |
| Ano: 2020 |
URL: https://archimer.ifremer.fr/doc/00662/77382/78981.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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| Pisapia, Francesco; Sibat, Manoella; Herrenknecht, Christine; Lhaute, Korian; Gaiani, Greta; Ferron, Pierre-jean; Fessard, Valerie; Fraga, Santiago; Nascimento, Silvia M.; Litaker, R. Wayne; Holland, William C.; Roullier, Catherine; Hess, Philipp. |
| Maitotoxins (MTXs) are among the most potent toxins known. These toxins are produced by epi-benthic dinoflagellates of the genera Gambierdiscus and Fukuyoa and may play a role in causing the symptoms associated with Ciguatera Fish Poisoning. A recent survey revealed that, of the species tested, the newly described species from the Canary Islands, G. excentricus, is one of the most maitotoxic. The goal of the present study was to characterize MTX-related compounds produced by this species. Initially, lysates of cells from two Canary Island G. excentricus strains VGO791 and VGO792 were partially purified by (i) liquid-liquid partitioning between dichloromethane and aqueous methanol followed by (ii) size-exclusion chromatography. Fractions from... |
| Tipo: Text |
Palavras-chave: Gambierdiscus excentricus; Maitotoxin-4; Bioguided fractionation; Size-exclusion chromatography (LH-20); Neuro-2a (N2a) assay; LC-HRMS/MS (Q-Tof 6550); LC-LRMS/MS (API4000 QTrap). |
| Ano: 2017 |
URL: http://archimer.ifremer.fr/doc/00392/50320/51001.pdf |
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| Mondeguer, Florence; Souard, Florence; Guitton, Yann; Allard, Pierre-marie; Elie, Nicolas; Sibat, Manoella; Latimier, Marie; Quere, Julien; Wolfender, Jean-luc; Siano, Raffaele; Hess, Philipp. |
| Aquatic ecosystems worldwide have been negatively affected by eutrophication, many of them driven by increasing nutrient inputs from untreated domestic sewage and industrial and agricultural wastewater. During their life cycle, Alexandrium minutum and Scrippsiella donghaienis can produce resistant and revivable cysts that can accumulate in the sediments of the coastal marine environment for hundreds of years. As a working hypothesis, we presumed that these two genera have preserved their adaptation to such ecosystem changes in the form of cysts in the old sediments. From revivified cysts, some cultures of toxic and non-toxic dinoflagellates (A. minutum and S. donghaienis) were analyzed by a metabolomic approach to study the possible adaptive responses of... |
| Tipo: Text |
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| Ano: 2018 |
URL: https://archimer.ifremer.fr/doc/00464/57591/59769.pdf |
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| Roué, Mélanie; Smith, Kirsty F.; Sibat, Manoella; Viallon, Jérôme; Henry, Kévin; Ung, André; Biessy, Laura; Hess, Philipp; Darius, Hélène Taiana; Chinain, Mireille. |
| Ciguatera poisoning is a foodborne illness caused by the consumption of seafood contaminated with ciguatoxins (CTXs) produced by dinoflagellates from the genera Gambierdiscus and Fukuyoa. The suitability of Solid Phase Adsorption Toxin Tracking (SPATT) technology for the monitoring of dissolved CTXs in the marine environment has recently been demonstrated. To refine the use of this passive monitoring tool in ciguateric areas, the effects of deployment time and sampler format on the adsorption of CTXs by HP20 resin were assessed in Anaho Bay (Nuku Hiva Island, French Polynesia), a well-known ciguatera hotspot. Toxicity data assessed by means of the mouse neuroblastoma cell-based assay (CBA-N2a) showed that a 24 h deployment of 2.5 g of resin allowed... |
| Tipo: Text |
Palavras-chave: Ciguatera monitoring; Gambierdiscus; Ciguatoxins; SPATT passive samplers; HP20 resin; CBA-N2a; LC-MS; MS; WS artificial substrate; QPCR; HTS metabarcoding. |
| Ano: 2020 |
URL: https://archimer.ifremer.fr/doc/00629/74143/73670.pdf |
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| Mondeguer, Florence; Sibat, Manoella; Reubrecht, Sébastien; Amzil, Zouher; Bormans, Myriam; Hess, Philipp; Briand, Enora. |
| Cyanobacterial proliferation is one of the most harmful hazards, in both freshwater and marine ecosystems. Cyanobacteria are well known for their ability to produce a wide variety of bioactive compounds, some of which have been described as allelochemicals. There is growing evidence that these secondary metabolites play an important role in shaping community composition through biotic interactions; however, for the most part, their biological role and mode of regulation of the production are poorly understood. In temperate eutrophic freshwaters, Microcystis and Planktothrix often co-occur, with Planktothrix being an early colonizer and Microcystis appearing subsequently. By integrating LC-MS/MS molecular networking and an innovative experimental design, we... |
| Tipo: Text |
Palavras-chave: Cyanobacteria; Cyanotoxins; Plankton interactions; Co_culture; LC_HRMS; Molecular Network; Metabolomics. |
| Ano: 2017 |
URL: http://archimer.ifremer.fr/doc/00405/51666/52215.pdf |
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| Briand, Enora; Reubrecht, Sébastien; Mondeguer, Florence; Sibat, Manoella; Hess, Philipp; Amzil, Zouher; Bormans, Myriam. |
| Freshwater cyanobacteria are known for their ability to produce bioactive compounds, some of which have been described as allelochemicals. Using a combined approach of co‐cultures and analyses of metabolic profiles, we investigated chemically mediated interactions between two cyanobacterial strains, Microcystis aeruginosa PCC7806 and Planktothrix agardhii PCC7805. More precisely, we evaluated changes in growth, morphology and metabolite production and release by both interacting species. Co‐culture of Microcystis with Planktothrix resulted in a reduction of the growth of Planktothrix together with a decrease of its trichome size and alterations in the morphology of its cells. The production of intracellular compounds by Planktothrix showed a slight... |
| Tipo: Text |
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| Ano: 2019 |
URL: https://archimer.ifremer.fr/doc/00470/58152/60632.pdf |
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| Estevez, Pablo; Sibat, Manoella; Leão-martins, José Manuel; Tudó, Angels; Rambla-alegre, Maria; Aligizaki, Katerina; Diogène, Jorge; Gago-martinez, Ana; Hess, Philipp. |
| Over the last decade, knowledge has significantly increased on the taxonomic identity and distribution of dinoflagellates of the genera Gambierdiscus and Fukuyoa. Additionally, a number of hitherto unknown bioactive metabolites have been described, while the role of these compounds in ciguatera poisoning (CP) remains to be clarified. Ciguatoxins and maitotoxins are very toxic compounds produced by these dinoflagellates and have been described since the 1980s. Ciguatoxins are generally described as the main contributors to this food intoxication. Recent reports of CP in temperate waters of the Canary Islands (Spain) and the Madeira archipelago (Portugal) triggered the need for isolation and cultivation of dinoflagellates from these areas, and their... |
| Tipo: Text |
Palavras-chave: Maitotoxins; Ciguatoxins; Gambierdiscus; Fukuyoa; LC-MS; MS; HRMS; QToF; Ciguatera poisoning. |
| Ano: 2020 |
URL: https://archimer.ifremer.fr/doc/00629/74081/73530.pdf |
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| Roue, Melanie; Darius, Helene Taiana; Ung, Andre; Viallon, Jerome; Sibat, Manoella; Hess, Philipp; Amzil, Zouher; Chinain, Mireille. |
| Ciguatera is a foodborne disease caused by the consumption of seafood contaminated with ciguatoxins (CTXs). Ciguatera-like poisoning events involving giant clams (Tridacna maxima) are reported occasionally from Pacific islands communities. The present study aimed at providing insights into CTXs tissue distribution and detoxification rate in giant clams exposed to toxic cells of Gambierdiscus polynesiensis, in the framework of seafood safety assessment. In a first experiment, three groups of tissue (viscera, flesh and mantle) were dissected from exposed individuals, and analyzed for their toxicity using the neuroblastoma cell-based assay (CBA-N2a) and liquid chromatography-tandem mass spectrometry (LC-MS/MS) analyses. The viscera, flesh, and mantle were... |
| Tipo: Text |
Palavras-chave: Giant clams; Ex situ exposure to toxic algae; Ciguatoxins; Gambierdiscus polynesiensis; Anatomical distribution; Toxin elimination; CBA-N2a; LC-MS/MS. |
| Ano: 2018 |
URL: https://archimer.ifremer.fr/doc/00440/55123/56579.pdf |
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| Darius, Helene Taiana; Roue, Melanie; Sibat, Manoella; Viallon, Jerome; Gatti, Clemence Mahana Iti; Vandersea, Mark W.; Tester, Patricia A.; Litaker, R. Wayne; Amzil, Zouher; Hess, Philipp; Chinain, Mireille. |
| Ciguatera fish poisoning (CFP) is a foodborne disease caused by the consumption of seafood (fish and marine invertebrates) contaminated with ciguatoxins (CTXs) produced by dinoflagellates in the genus Gambierdiscus. The report of a CFP-like mass-poisoning outbreak following the consumption of Tectus niloticus (Tegulidae, Gastropod) from Anaho Bay on Nuku Hiva Island (Marquesas archipelago, French Polynesia) prompted field investigations to assess the presence of CTXs in T. niloticus. Samples were collected from Anaho Bay, 1, 6 and 28 months after this poisoning outbreak, as well as in Taiohae and Taipivai bays. Toxicity analysis using the neuroblastoma cell-based assay (CBA-N2a) detected the presence of CTXs only in Anaho Bay T. niloticus samples. This is... |
| Tipo: Text |
Palavras-chave: Ciguatera poisoning; Ciguatoxins; Tectus niloticus; Gastropods; Gambierdiscus polynesiensis; QPCR assays; CBA-N2a; LC-MS; MS. |
| Ano: 2018 |
URL: https://archimer.ifremer.fr/doc/00426/53798/54719.pdf |
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| Amzil, Zouher; Sibat, Manoella; Chomerat, Nicolas; Grossel, Hubert; Marco-miralles, Francoise; Lemee, Rodolphe; Nezan, Elisabeth; Sechet, Veronique. |
| Dinoflagellates of the genus Ostreopsis are known to cause (often fatal) food poisoning in tropical coastal areas following the accumulation of palytoxin (PLTX) and/or its analogues (PLTX group) in crabs, sea urchins or fish. Ostreopsis spp. occurrence is presently increasing in the northern to north western Mediterranean Sea (Italy, Spain, Greece and France), probably in response to climate change. In France, Ostreopsis. cf. ovata has been associated with toxic events during summer 2006, at Morgiret, off the coast of Marseille, and a specific monitoring has been designed and implemented since 2007. Results from 2008 and 2009 showed that there is a real danger of human poisoning, as these demonstrated bioaccumulation of the PLTX group (PLTX and ovatoxin-a)... |
| Tipo: Text |
Palavras-chave: Ostreopsis cf. ovata; Palytoxin; Ovatoxin-a; LC-MS/MS; Seafood. |
| Ano: 2012 |
URL: http://archimer.ifremer.fr/doc/00071/18230/15799.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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| Registros recuperados: 40 | |
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