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| Registros recuperados: 40 | |
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| Geiger, Marie; Desanglois, Gwenaelle; Hogeveen, Kevin; Fessard, Valerie; Lepretre, Thomas; Mondeguer, Florence; Guitton, Yann; Herve, Fabienne; Sechet, Veronique; Grovel, Olivier; Pouchus, Yves-francois; Hess, Philipp. |
| Pinnatoxin G (PnTX-G) is a marine toxin belonging to the class of cyclic imines and produced by the dinoflagellate Vulcanodinium rugosum. In spite of its strong toxicity to mice, leading to the classification of pinnatoxins into the class of “fast-acting toxins”, its hazard for human health has never been demonstrated. In this study, crude extracts of V. rugosum exhibited significant cytotoxicity against Neuro2A and KB cells. IC50 values of 0.38 µg mL−1 and 0.19 µg mL−1 were estimated on Neuro2A cells after only 24 h of incubation and on KB cells after 72 h of incubation, respectively. In the case of Caco-2 cells 48 h after exposure, the crude extract of V. rugosum induced cell cycle arrest accompanied by a dramatic increase in double strand DNA breaks,... |
| Tipo: Text |
Palavras-chave: Dereplication; Cyclic imine; HRMS; Bioactivity; Pinnatoxins. |
| Ano: 2013 |
URL: http://archimer.ifremer.fr/doc/00156/26723/24802.pdf |
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| Guitton, Yann; Mondeguer, Florence; Nicolau, Elodie; Royer, Florence; Hilbert, Jean-louis; Fournier, Isabelle; Wisztorski, Maxence. |
| MALDI Mass Spectrometry Imaging (MALDI-MSI) is a two-dimensional MALDI mass spectrometric technique used to visualize the spatial distribution of a large variety of biological molecules (from small metabolites to large proteins) without extraction, purification, separation or labelling of biological samples. Since its introduction by Caprioli et al in 1997, it has become one of the most important molecular histology methods for biomarker hunting and for understanding the spatial distribution of biomolecules in various tissues. MALDI-MSI is thus ideal for complementing the expanding field of metabolomics. Despite the fact that MALDI-MSI have been very successfully applied in divers studies (even in clinical applications) its use remains far from routine,... |
| Tipo: Text |
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| Ano: 2012 |
URL: http://archimer.ifremer.fr/doc/00179/29041/27479.pdf |
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| Zendong, Zita; Herrenknecht, Christine; Abadie, Eric; Brissard, Charline; Tixier, Celine; Mondeguer, Florence; Sechet, Veronique; Amzil, Zouher; Hess, Philipp. |
| Marine biotoxins are algal metabolites that can accumulate in fish or shellfish and render these foodstuffs unfit for human consumption. These toxins, released into seawater during algal occurrences, can be monitored through passive sampling. Acetone, methanol and isopropanol were evaluated for their efficiency in extracting toxins from algal biomass. Isopropanol was chosen for further experiments thanks to a slightly higher recovery and no artifact formation. Comparison of Oasis HLB, Strata-X, BondElut C18 and HP-20 sorbent materials in SPE-mode led to the choice of Oasis HLB, HP-20 and Strata-X. These three sorbents were separately exposed as passive samplers for 24 h to seawater spiked with algal extracts containing known amounts of okadaic acid (OA),... |
| Tipo: Text |
Palavras-chave: Passive sampling; Oasis HLB; Strata-X; LOPE; PDMS; SPATT. |
| Ano: 2014 |
URL: https://archimer.ifremer.fr/doc/00186/29756/28187.pdf |
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| Fux, E; Marcaillou-le Baut, Claire; Mondeguer, Florence; Bire, R; Hess, Philipp. |
| It has been demonstrated that polymeric resins can be used as receiving phase in passive samplers designed for the detection of lipophilic marine toxins at sea and was referred to as solid phase adsorption toxin tracking (SPATT). The present study describes the uptake and desorption behaviour of the lipophilic marine toxins okadaic acid (OA) and dinophysistoxin-1 (DTX1) from Prorocentrum lima cultures by five styrene-divinylbenzene based polymeric resins Sepabeads (R) SP850, Sepabeads (R) SP825L, Amberlite (R) XAD4, Dowex (R) Optipore (R) L-493 and Diaion (R) HP-20. All resins accumulated OA and DTX1 from the P. lima culture with differences in adsorption rate and equilibrium rate. Following statistical evaluation, HP-20, SP850 and SP825L demonstrated... |
| Tipo: Text |
Palavras-chave: Polymeric resin; Dinophysistoxin 1; Okadaic acid; SPATT; Prorocentrum lima. |
| Ano: 2008 |
URL: http://archimer.ifremer.fr/doc/2008/publication-4739.pdf |
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| Mondeguer, Florence; Marcaillou-le Baut, Claire. |
| Le littoral français est touché tous les ans par des proliférations d'algues toxiques dont l'ampleur géographique et la durée sont très variables selon les genres/espèces et les années. Par exemple, à partir du mois de mai, voire fin avril certaines années, les côtes sud de la Bretagne et celles des Pays de la Loire sont touchées par des proliférations de Dinophysis spp, genre responsable des intoxications diarrhéiques et cause la plus fréquente des fermetures de zones conchylicoles. Depuis 1988, la côte nord de la Bretagne est exposée à des efflorescences à Alexandrium minutum, producteur de toxines paralysantes. Ces fermetures répétées s'accompagnent d'une diminution, voire d'une cessation d'activité pour les établissements d'expédition car... |
| Tipo: Text |
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| Ano: 2005 |
URL: http://archimer.ifremer.fr/doc/00154/26512/24630.pdf |
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| Mondeguer, Florence. |
| Metabolomics is a new approach to assess the contamination of organisms, environmental compartments or foodstuffs, and the impact marine pollution, (natural or anthropogenic), can have on them. Through the analysis of the variation of the metabolite profiles present in the cell, tissues, organs or even the whole organism it is possible to define a physiological state, a stage of development, or the level and nature of a contamination. Generally, analysis of metabolites correlates to experimental design built around a clear biological or environmental question, needs to be supported by sensitive and reproducible tools, and requires access to libraries "house" or international. Often, the non-targeted approach allows for evaluation of many hypotheses. Thus,... |
| Tipo: Text |
Palavras-chave: Biotoxines; Biomarqueurs; Métabolomique; Microalgues; Moules; Spectrométrie de masse haute résolution (HRMS); Workflow. |
| Ano: 2016 |
URL: http://archimer.ifremer.fr/doc/00358/46892/46777.pdf |
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| Lepinay, Alexandra; Capiaux, Herve; Turpin, Vincent; Mondeguer, Florence; Lebeau, Thierry. |
| Haslea ostrearia produces a water-soluble, blue-green pigment, called marennine, with proven economic benefits (as a bioactive compound used to green oysters, which improves their market value). Incomplete knowledge of the ecological features of this marine diatom complicates its cultivation. More specifically, the ecology of bacteria surrounding H. ostrearia in ponds is what remains unknown. The structure of this bacterial community was previously analyzed by means of PCR-TTGE before and after isolating H. ostrearia cells recovered from 4 localities in order to distinguish the relative parts of the biotope and biocenose and to describe the temporal dynamics of the bacterial community structure at two time scales (2 weeks vs. 9 months). The bacterial... |
| Tipo: Text |
Palavras-chave: Biofilm; Ecology; Metabolic fingerprinting; Microalgae; Phycosphere; TTGE. |
| Ano: 2016 |
URL: https://archimer.ifremer.fr/doc/00326/43737/43344.pdf |
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| Hess, Philipp; Geiger, Marie; Brochard, Solène; Lepretre, Thomas; Fessard, Valerie; Antignac, Jean-philippe; Dupont, Jacques; Sechet, Veronique; Vanel, Faustine; Mondeguer, Florence; Herve, Fabienne; Leborgne, Sabrina; Deslanglois, Gwenaëlle; Marshall, Lindsey; Rounds, Lucy; Guitton, Yann; Amzil, Zouher; Grovel, Olivier; Ruiz, Nicolas; Pouchus, Francois. |
| Cette étude s’est inscrite dans un contexte d’évaluation de la salubrité des mollusques bivalves destinés à la consommation humaine. Ces organismes peuvent en effet accumuler des toxines, en particulier de microalgues, en concentrations importantes, pouvant induire des intoxications chez les personnes les consommant. Afin d’assurer la protection des consommateurs, les toxines réglementées sont recherchées dans les coquillages par techniques physico-chimiques. En parallèle, les toxines émergentes, potentiellement produites par d’autres organismes que les micro-algues telles que les micromycètes, peuvent être detectées par l’utilisation du test de toxicité aigüe sur souris. Cependant, ce bio-essai présente de très nombreux inconvénients, notamment éthiques... |
| Tipo: Text |
Palavras-chave: Cytotoxicité; Toxicité sur larves de diptères; Activité antibactérienne; Bactéries marines; Toxines lipophiles; Micro-algues; Dinoflagellés; Micromycètes; Penicillium; Acide okadaïque; Azaspiracide; Pinnatoxine G; Vulcanodinium rugosum; Prorocentrum lima; Azadinium spinosum; Beauveria brongniartii. |
| Ano: 2015 |
URL: http://archimer.ifremer.fr/doc/00253/36470/35015.pdf |
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| Mondeguer, Florence; Antignac, Jean-philippe; Guitton, Yann; Monteau, Fabrice; Le Borgne, Sabrina; Hess, Philipp. |
| La bioactivité des toxines du phytoplancton qui s’accumulent dans les coquillages est presque toujours évaluée sur modèle animal (test souris). Malgré ses avantages, la capacité de ce test à expliquer la nature de cette bio-activité reste limitée. Par ailleurs, le contrôle sanitaire actuellement basé sur une méthode ciblée d’identification et de quantification d’un ensemble de toxines connues ne permet pas de détecter des toxines encore inconnues. Afin de répondre à ce besoin de caractérisation de substances toxiques inconnues, une nouvelle approche de profilage chimique différentiel et non ciblé, de type métabolomique, a été proposée. Les 2 extraits sélectionnés sont ceux ayant montré une toxicité positive chez la souris, sans que les substances... |
| Tipo: Text |
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| Ano: 2013 |
URL: http://archimer.ifremer.fr/doc/00179/29042/27480.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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| 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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| Poyer, Salomé; Loutelier-bourhis, Corinne; Mondeguer, Florence; Coadou, Gaël; Hubert-roux, Marie; Enche, Julien; Bossee, Anne; Hess, Philipp; Afonso, Carlos. |
| Saxitoxin and its analogues also called paralytic shellfish poisons (PSPs) are very potent neurotoxins [1] produced by dinoflagellates and referenced as chemical weapon in the chemical warfare convention (CWC). The official detection methods for these toxins present limitations concerning their speed and reliability [2]. Due to the presence of isomers, not differentiable by mass spectrometry (MS), an upstream separation is necessary. In order to separate saxitoxin analogues, hydrophilic interaction liquid chromatography (HILIC) and ion mobility (IM) were used. Those techniques respectively developed for high polar compounds and three dimensional structure differentiation are particularly well adapted to the separation of PSPs. This HILIC/IM-MS coupling... |
| Tipo: Text |
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| Ano: 2013 |
URL: http://archimer.ifremer.fr/doc/00179/29039/27475.pdf |
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| Poyer, Salome; Loutelier-bourhis, Corinne; Coadou, Gael; Mondeguer, Florence; Enche, Julien; Bossee, Anne; Hess, Philipp; Afonso, Carlos. |
| The aim of this work was to develop a reliable and efficient analytical method to characterise and differentiate saxitoxin analogues (STX), including sulphated (gonyautoxins, GTX) and non-sulphated analogues. For this purpose, hydrophilic interaction liquid chromatography (HILIC) was used to separate sulphated analogues. We also resorted to ion mobility spectrometry to differentiate the STX analogues because this technique adds a new dimension of separation based on ion gas phase conformation. Positive and negative ionisation modes were used for gonyautoxins while positive ionisation mode was used for non-sulphated analogues. Subsequently, the coupling of these three complementary techniques, HILIC-IM-MS, permitted the separation and identification of STX... |
| Tipo: Text |
Palavras-chave: Saxitoxin; Ion mobility-mass spectrometry; Isomers; Multidimensional separation; HILIC. |
| Ano: 2015 |
URL: https://archimer.ifremer.fr/doc/00249/36067/34924.pdf |
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| Delporte, C; Vanhaverbeke, C; Noret, N; Van Anterpwen, P; Stévigny, C; Hardy, O; Mondeguer, Florence; Touboul, David; Souard, Florence. |
| To highlight plant adaptive traits, we have observed the metabolome from leaves of wild type tropical Erythrophleum genus that includes the set of particular metabolites present in an organ at a certain time. To answer those ecological questions, genetic approaches as neutral genetic markers (like microsatellites) are usually used to evaluate how evolutionary forces interact to shape phenotypic variations observed among natural populations. As metabolites are the result of a complex network of gene expression, protein expression and interactions and other regulatory processes, they are therefore closer to the phenotype than transcriptome or proteome. Secondary metabolites resulting from specific biosynthetic pathways possess characteristic structural... |
| Tipo: Text |
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| Ano: 2019 |
URL: https://archimer.ifremer.fr/doc/00498/60935/64331.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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| Mondeguer, Florence; Antignac, Jean-philippe; Guitton, Yann; Monteau, Fabrice; Le Borgne, Sabrina; Hess, Philipp. |
| The bioactivity of phytoplankton toxins that accumulate in shellfish is almost always tested on animal model (mice assay). In spite of these advantages, the ability of this test to explain the nature of the bioactivity remains limited. Besides, the current sanitary control based on targeted methods of identification and quantification (LC-MS/MS) of known toxins, do not permit to detect unknown toxins. In order to cope with this need of identification of unknown toxic substances, a next approach based on global and differential metabolomic profiling was proposed. The first results obtained from extracts that have shown a positive toxicity in mice without the substances potentially responsible for these toxic effects have been measured by targeted methods,... |
| Tipo: Text |
Palavras-chave: Métabolomique; LC-HRMS; Biotoxines marines; Biomarqueur. |
| Ano: 2012 |
URL: http://archimer.ifremer.fr/doc/00077/18784/16352.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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| Registros recuperados: 40 | |
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