Consulta: creatorFacets:"Mondeguer, Florence"
Registros recuperados: 40
Data/hora: 04/06/2024 12:13:55

Cytotoxicity, Fractionation and Dereplication of Extracts of the Dinoflagellate Vulcanodinium rugosum, a Producer of Pinnatoxin G
Provedor de dados: 5
Autores: 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

Maldi mass spectrometry imaging applied to small molecules localization
Provedor de dados: 5
Autores: 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
Ano: 2012
URL: http://archimer.ifremer.fr/doc/00179/29041/27479.pdf

Extended evaluation of polymeric and lipophilic sorbents for passive sampling of marine toxins
Provedor de dados: 5
Autores: 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

Field and mesocosm trials on passive sampling for the study of adsorption and desorption behaviour of lipophilic toxins with a focus on OA and DTX1
Provedor de dados: 5
Autores: 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

Etude d'un système de filtration de l'eau de mer pour l'alimentation des bassins conchylicoles insubmersibles durant des efflorescences toxiques. Rapport de fin de contrat : Cas d'une efflorescence à Alexandrium minutum et à Dinophysis spp
Provedor de dados: 5
Autores: 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
Ano: 2005
URL: http://archimer.ifremer.fr/doc/00154/26512/24630.pdf

La métabolomique et les biotoxines marines
Provedor de dados: 5
Autores: 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

Un nouvel outil dans l'identification et la quantification des dinophysistoxines (DTXs) : le couplage Chromatographie Liquide Haute Performance / Spectrométrie de masse par piégeage d'ions quadripôlaire et interface d'électro- nébulisation (CLHP/SM2)
Provedor de dados: 5
Autores: Mondeguer, Florence.
This report presents a new method for detection and confirmed quantification of dinophysistoxins (DTXs) using high-performance liquid chromatography coupled to mass spectrometry with an ion trap and électrospray interface (HPLC/ESI/MS2).  The parameters of the ESI source and ion trap spectrum analyser were optimised to provide detection of DTXs with maximum sensitivity. These improvements were obtained after reverse-phase separation on a C18 column, with a first elution to 0.1% TFA (75:25, v/v) in isocratic acetonitrile/water mode without flow split at a column flow rate of 200 µl/min for 15 min. A second elution gradient step was added to allow optimised processing of long series of analyses without signal obstruction. This method was validated...
Tipo: Text
Palavras-chave: Intoxication par les coquillages; Dinophysistoxines; Acide okadaïque; Dinophysistoxine-1; Couplage CLHP-électronébulisation- SM2 par piège d'ions; Toxines.; Shellfish poisoning; Dinophysistoxines; Okadaïque Acid; Dinophysistoxine-1; Liquid Chromatography coupled Ion Trap; Toxins.
Ano: 2002
URL: http://archimer.ifremer.fr/doc/00136/24763/22839.pdf

Bacterial community structure of the marine diatom Haslea ostrearia
Provedor de dados: 5
Autores: 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

Contribution to toxicity assessment of Dinophysis acuminata (Dinophyceae)
Provedor de dados: 5
Autores: Marcaillou-le Baut, Claire; Mondeguer, Florence; Gentien, Patrick.
Blooms of Dinophysis in French coastal waters are implicated in most bans on marketing commercial bivalves. However, the relation between Dinophysis cell density and shellfish toxicity is not always consistent. Discrepancies may be due to the simple fact that it is nearly impossible to compare an integral over a few days (shellfish toxin content) and water samples. Furthermore, it seems that cells may have a variable specific toxicity. This work focuses on the variability in cell toxicity taking into account recent findings and using liquid chromatography coupled to mass spectrometry with an ion trap and electrospray interface. Esterified analogues of okadaic acid (DTX-4 and diol-esters) have been identified in cultures of Prorocentrum lima, another...
Tipo: Text
Palavras-chave: Liquid chromatography electrospray ionization mass spectrometry; Okadaic acid; Dinophysistoxins; Dinophysis acuminata.
Ano: 2005
URL: http://archimer.ifremer.fr/doc/2005/publication-605.pdf

COLNACOQ. Composés lipophiles naturels dans l’environnement des coquillages. Rapport final
Provedor de dados: 5
Autores: 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

Stratégie de mesure non ciblée de type métabolomique (couplage LC-HRMS ) pour identifier différents groupes de composés bioactifs accumulés dans les mollusques bivalves
Provedor de dados: 5
Autores: 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
Ano: 2013
URL: http://archimer.ifremer.fr/doc/00179/29042/27480.pdf

Chemically mediated interactions between Microcystis and Planktothrix: Impact on their physiology and metabolic profiles
Provedor de dados: 5
Autores: 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
Ano: 2017
URL: http://archimer.ifremer.fr/doc/00374/48515/48794.pdf

First insight on metabolomics workflows and differences between dinoflagellate: characterization and discrimination of modern and ancient strains and their algal growth
Provedor de dados: 5
Autores: 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
Ano: 2018
URL: https://archimer.ifremer.fr/doc/00440/55199/56664.pdf

Identification of paralytic shellfish poisons using liquid chromatography / ion mobility - high resolution mass spectrometry
Provedor de dados: 5
Autores: 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
Ano: 2013
URL: http://archimer.ifremer.fr/doc/00179/29039/27475.pdf

Identification and separation of saxitoxins using hydrophilic interaction liquid chromatography coupled to traveling wave ion mobility-mass spectrometry
Provedor de dados: 5
Autores: 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

Molecular networking on wild “Tali” (Erythrophleum, Fabaceae) from Central tropical Africa
Provedor de dados: 5
Autores: 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
Ano: 2019
URL: https://archimer.ifremer.fr/doc/00498/60935/64331.pdf

Innovative metabolomic workflows to study growth kinetics dinoflagellate cysts revived from modern and ancient sediments
Provedor de dados: 5
Autores: 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
Ano: 2018
URL: https://archimer.ifremer.fr/doc/00464/57591/59769.pdf

Nouvelle stratégie de caractérisation non ciblée de type métabolomique au service de l’identification de composés bioactifs accumulés dans les mollusques bivalves
Provedor de dados: 5
Autores: 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

Preliminary metabolomic approach on cyanobacterial co-cultures: Chemically mediated interactions between Microcystis and Planktothrix
Provedor de dados: 5
Autores: 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

Chemically mediated interactions between   Microcystis   and   Planktothrix   : impact on their growth, morphology and metabolic profiles
Provedor de dados: 5
Autores: 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
Ano: 2019
URL: https://archimer.ifremer.fr/doc/00470/58152/60632.pdf

Metabolomics based on UHPLC-QToF- and APGC-QToF-MS reveals metabolic pathways reprogramming in response to tidal cycles in the sub-littoral species Mimachlamys varia exposed to aerial emergence
Provedor de dados: 5
Autores: Ory, Pascaline; Bonnet, Antoine; Mondeguer, Florence; Breitwieser, Marine; Dubillot, Emmanuel; Graber, Marianne.
Mimachlamys varia is a sub-littoral bivalve encountered from Norway to the Mediterranean Sea, which lives mostly byssally attached to rocks. During the low tide period, M. varia individuals, located highest on the shore, may experience short time of aerial exposure and face a low availability of oxygen. Here we report a comparative metabolomic profiling of gill samples of M. varia obtained by both LC-QToF and APGC-QToF mass spectrometry, to analyze metabolic changes occurring during emersion in comparison with immersion. Scallops were grown in aquaria with a simulated intertidal environment mimicking short-duration air exposure that they might experience during extreme tides: alternating 2 h emersion and 10 h immersion. Our results show a switch from...
Tipo: Text
Palavras-chave: Anaerobic; APGC-QToF mass spectrometry; Hypoxia; Intertidal; LC-QToF mass spectrometry; Metabolomics; Mimachlamys varia; PLS-DA.
Ano: 2019
URL: https://archimer.ifremer.fr/doc/00466/57741/59936.pdf

Metabolomic approach for the analysis of micro-algae : direct analysis versus passive sampling
Provedor de dados: 5
Autores: Zendong, Suzie Zita; Herrenknecht, Christine; Mondeguer, Florence; Hess, Philipp.
By 2014, the new targeted LC-MS/MS reference method for the detection of lipophilic toxins will replace the mouse bioassay (MBA). This bioassay, which has the advantage of being a rapid and global toxicity test, can not be used for toxin identification purposes. Furthermore, it has appeared that, in some cases, the mouse bioassay could reveal uncharacterized toxicities that could not be elucidated by targeted mass spectrometry methods. Therefore, moving from the global toxicity assessment test to a targeted technique leads to a lack of information on emerging toxins. Objectives: - Beside targeted methods, develop metabolomic approaches to screen for known and unknown emerging toxins - Develop passive sampling devices suitable for toxins of varying...
Tipo: Text
Ano: 2013
URL: http://archimer.ifremer.fr/doc/00179/29040/27478.pdf

First metabolomic approach of the epiphytic bacteria-marine diatom Haslea ostrearia relationships
Provedor de dados: 5
Autores: Mondeguer, Florence; Lepinay, Alexandra; Capiaux, Hervé; Turpin, Vincent; Baron, Regis; Hess, Philipp; Lebeau, Thierry; Boug,.
The marine diatom Haslea ostrearia [1] produces a water-soluble blue-pigment named marennine [2] of economic interest. But the lack of knowledge of the ecological conditions, under which this microalga develops in its natural ecosystem, more especially bacteria H. ostrearia interactions, prevents any optimization of its culture in well-controlled conditions.  The structure of the bacterial community was analyzed by PCR-TTGE before and after the isolation of H. ostrearia cells recovered from 4 localities, to distinguish the relative part of the biotope and the biocenose and eventually to describe the temporal dynamic of the structure of the bacterial community at two time-scales. The differences in genetic fingerprints, more especially high between two H....
Tipo: Text
Palavras-chave: Haslea ostrearia; Marine diatom; Co-culture microalgae; Bacterial community; PCR-TTGE; High Resolution Mass Spectrometry; Untargeted metabolomics.
Ano: 2016
URL: https://archimer.ifremer.fr/doc/00342/45367/44862.pdf

Etude succincte d'échantillons de bivalves et de phytoplancton
Provedor de dados: 5
Autores: Lassus, Patrick; Le Baut, Claire; Mondeguer, Florence; Bohec, Madeleine.
A la suite du stage réalisé par Geneviève Arzul dans différents laboratoires chiliens travaillant sur les microalgues toxiques, des échantillons provenant de Cochamo (estuaire de Relonarvi) ont été étudiés par le Laboratoire DEUPN de Nantes. Il s'agissait de prélèvements phytoplanctoniques riches en Dinophysis et fixés au formol, ainsi que de glandes digestives d'Aulacomya ater conservées dans 100 ml d'acétone.
Tipo: Text
Ano: 1993
URL: http://archimer.ifremer.fr/doc/00156/26714/24789.pdf

Determination of peptaibol trace amounts in marine sediments by liquid chromatography/electrospray ionization-ion trap-mass spectrometry
Provedor de dados: 5
Autores: Poirier, Laurence; Amiard, Jean-claude; Mondeguer, Florence; Quiniou, Francoise; Ruiz, Nicolas; Pouchus, Yves Francois; Montagu, Monique.
Extraction followed by reverse phase liquid chromatography (LC)/electrospray ionization-ion trap-mass spectrometry (ESI-IT-MS) analysis has been successfully developed for the determination of peptaibols, fungal toxic metabolites, in marine sediments. Spiking experiments showed that the mean recovery of target compounds exceeded 85% at a spiking level of 10 ng/g of sediment (wet weight). Detection and quantification limits were 250 and 830 pg/g of sediment, respectively. The method developed constituted the first sensitive assay for quantification of peptaibol trace amounts in a natural environment. A concentration of 5 ng/g in sediment samples collected from Fier d'Ars was found.
Tipo: Text
Palavras-chave: Matched calibration; Matrix; Electrospray ionization ion trap mass spectrometry ESI IT MS; Marine fungal contamination; Trichoderma sp.; Fungal peptide metabolites.
Ano: 2007
URL: http://archimer.ifremer.fr/doc/2007/publication-2990.pdf

Pinnatoxines en lien avec l’espèce Vulcanodinium rugosum (II)
Provedor de dados: 5
Autores: Mondeguer, Florence; Abadie, Eric; Herve, Fabienne; Bardouil, Michele; Sechet, Veronique; Raimbault, Virginie; Berteaux, Tom; Zendong, Suzie Zita; Palvadeau, Hubert; Amzil, Zouher; Hess, Philipp; Fessard, Valérie; Huguet, Antoine; Sosa, Silvio; Tubaro, Aurelia; Aráoz, Rómulo; Molgó, Jordi.
Pour tenter d’apporter des réponses aux questions soulevées par une précédente étude commanditée pour approfondir les connaissances sur Vulcanodinium rugosum, l’organisme producteur de la Pinnatoxine G (PnTX G) (Hess et al., 2012), les objectifs de cette nouvelle étude sont les suivants : - Elargissement de la zone initiale de prélèvement d’Ingril à toute la lagune méditerranéenne et mise à profit de l’augmentation du nombre d’échantillons pour vérifier l’impact de l’effet matrice dans l’analyse LC-SM/MS. - Mise en culture en masse de Vulcanodinium rugosum et - Conduite d’une expérience de contamination in vivo sur des moules pour vérifier l’accumulation de la PnTX-G et comprendre les mécanismes de la métabolisation des PnTXs et de ses composés associés.....
Tipo: Text
Ano: 2015
URL: http://archimer.ifremer.fr/doc/00285/39635/38126.pdf

Differentiation of gonyautoxins by ion mobility - mass spectrometry; a cationization study
Provedor de dados: 5
Autores: Poyer, Salome; Loutelier-bourhis, Corinne; Tognetti, Vincent; Joubert, Laurent; Enche, Julien; Bossee, Anne; Mondeguer, Florence; Hess, Philipp; Afonso, Carlos.
Gonyautoxins are potent natural neurotoxic analogues of saxitoxin. Due to their biological activity and submilligram lethal dose for man, fast and efficient methods are required for their characterization. Recent advances in ion mobility-mass spectrometry (IM-MS) showed that differentiation of isomers could be achieved using specific experimental conditions involving particular buffer gases as well as cationic species. In this work, IM-MS experiments were carried out using alkali metal ions (Met = Li+, Na+ or K+) and different buffer gases (N2, N2O and CO2) to improve the differentiation of gonyautoxin isomers. The separation of [GTX + Met]+ ion was achieved for GTX2/3 and GTX1/4 from their Na or K adducts. For dcGTX2/3, the ion mobility separation can...
Tipo: Text
Palavras-chave: Ion mobility; Gonyautoxin; Collision cross-section; Alkali adduct.
Ano: 2016
URL: http://archimer.ifremer.fr/doc/00317/42863/42291.pdf

Validation d’un procédé automatisé d’extraction par SPE pour identifier et quantifier les dinophysistoxines en LC/ESI/SM/SM par piégeage d’ions
Provedor de dados: 5
Autores: Mondeguer, Florence.
A new extraction method (SPE) for detection and quantification of dinophysistoxins (DTXs) using highperformance liquid chromatography coupled to mass spectrometry with an ion trap and electrospray interface (HPLC/ESI/MS2) was elaborated. This report presents development and validation of this method. Parameters of the ESI source and ion trap spectrum analyser were optimized providing detection of DTXs with high sensitivity. These improvements were obtained after reverse-phase separation on a C18 column, with a first elution to 0.1% TFA (75:25, v/v) in isocratic acetonitrile /water mode without flow split with a column flow rate of 200 Jl/min for 15 min. A second elution gradient step was added allowing an optimised processing of long series of analyses...
Tipo: Text
Ano: 2007
URL: http://archimer.ifremer.fr/doc/00136/24764/22830.pdf

Detection of griseofulvin in a marine strain of Penicillium waksmanii by ion trap mass spectrometry
Provedor de dados: 5
Autores: Petit, Karina; Mondeguer, Florence; Roquebert, M; Biard, J; Pouchus, Y.
A marine strain of Penicillium waksmanii Zaleski was isolated from a sample of seawater from shellfish-farming area in the Loire estuary (France). The in vitro marine culture showed an important antifungal activity. Bioassay-guided fractionation was used to purify the crude extract. Dereplication by electrospray-ion trap/mass spectrometry (ESI-IT/MS) afforded the identification of the antifungal compound, after a semi-purification consisting of two stages. A comparison of the ionic composition between the active and the non-active fractions allowed the detection of a monocharged ion at m/z 353 containing a chlorine atom, which could be attributed to the antifungal griseofulvin [C17H17ClO6+H](+). Multi-stage fragmentation (MSn) confirmed the identity of the...
Tipo: Text
Palavras-chave: Mass spectrometry ESI IT/MS; Griseofulvin; Antifungal; Marine fungi; Penicillium waksmanii.
Ano: 2004
URL: http://archimer.ifremer.fr/doc/2004/publication-673.pdf

COMSAUMOL (maintien de la COMmercialisation par la SAUvegarde et la détoxication des MOLlusques). Etude 2008-2010. Rapport final
Provedor de dados: 5
Autores: Haure, Joel; Hussenot, Jerome; Buzin, Florence; Dupuy, Beatrice; Palvadeau, Hubert; Penisson, Christian; Papin, Mathias; Nourry, Max; Lassus, Patrick; Marcaillou-le Baut, Claire; Mondeguer, Florence; Royer, F.; Amzil, Zouher; Belin, Catherine; Cardinal, Mireille; Le Grel, L.; Le Bihan, V.; Jaouen, P.; Massé, A.; Castaing, Jean-baptiste; Sabiri, Ne.; Pontié, M.
La contamination des denrées d’origine marine par des toxines algales (phycotoxines) a pris depuis quelques années une importance considérable. Ce phénomène est largement lié à l’augmentation du nombre de zones géographiques touchées ainsi qu’à la diversification des espèces toxinogènes et à l’identification de nouveaux composés toxiques. Les données épidémiologiques sont cependant encore peu nombreuses car elles sont liées à la mise en place de contrôles systématiques récents. L’Union Européenne a établi un Laboratoire Communautaire de référence pour les phycotoxines, situé à Vigo (Espagne) qui coordonne les activités des laboratoires Nationaux de références correspondants (en France c’est le LNR Phycotoxines de l’AFSSA qui assure cette mission). C’est...
Tipo: Text
Ano: 2011
URL: http://archimer.ifremer.fr/doc/00092/20277/17922.pdf

COSELMAR. Compréhension des socio-écosystèmes littoraux et marins pour la prévention et la gestion des risques. Bilan scientifique 2013-2017
Provedor de dados: 5
Autores: Pardo, Sophie; Hess, Philipp; Simon, Elodie; Barille, Laurent; Geslin, Emmanuelle; Cognie, Bruno; Martin-jezequel, Véronique; Sechet, Véronique; Herrenknecht, Christine; Baron, Regis; Bourseau, Patrick; Amzil, Zouher; Masse, Anthony; Vandanjon, Laurent; Dumay, Justine; Lebeau, Thierry; Turpin, Vincent; Mondeguer, Florence; Petitgas, Pierre; Trouillet, Brice; Mercier, Denis; Guillotreau, Patrice; Guineberteau, Thierry; Mahevas, Stephanie; Schoefs, Franck; Sophie Pardo; Philipp Hess; Pauline Borgniet; Laurent Barillé; Emmanuelle Geslin; Bruno Cognie; Véronique Martin-Jezequel; Véronique Sechet; Christine Herrenknecht; Régis Baron; Patrick Bourseau; Zouher Amzil; Anthony Massé; Laurent Vandanjon; Justine Dumay; Thierry Lebeau; Vincent Turpin; Florence Mondeguer; Pierre Petitgas; Brice Trouillet.
COSELMAR, a 4-year project financed by the Région des Pays de la Loire at 2.1 M€, officially started on the 7th January 2013. The project is coordinated by Philipp Hess (IFREMER) and Sophie Pardo (Université de Nantes-LEMNA) and falls under the Federation for Research Institut Universitaire Mer et Littoral (IUML, FR CNRS 3473)*. COSELMAR has also been approved by the Scientific Council of the MSH Ange Guépin. COSELMAR is a research project uniting 5 research units of IFREMER and 11 laboratories of the Université de Nantes, along with academic partners, and national and international industries. The aim is to achieve a better understanding of the marine and coastal ecosystems and the associated resources. The project will also provide insights into risk...
Tipo: Text
Ano: 2017
URL: https://archimer.ifremer.fr/doc/00406/51793/52550.pdf

Workflows novateurs pour une analyse métabolomique plus claire et plus intégrative
Provedor de dados: 5
Autores: Mondeguer, Florence; Allard, Pierre-marie; Souard, Florence; Elie, Nicolas; Guitton, Yann; Sibat, Manoella; Siano, Raffaele.
During their life cycle, Alexandrium minutum and Scrippsiella donghaienis can produce resistant and revivable cysts that can accumulate in marine sediments for hundreds of years. Our working hypothesis assumes that these two genera have "recorded" their adaptation to ecosystem changes in these cells preserved in the form of cysts. From these revived cysts, toxic and non-toxic dinoflagellate cultures (Alexandrium minutum and Scrippsiella donghaienis) were analyzed by a metabolomic approach to investigate the possible adaptive responses of phytoplankton to these changes in coastal ecosystems. The strains were obtained from isotopically dated sediments, 1986 and 1996 for "old" and 2006 for "modern". In total, 84 samples were obtained. Each experimental...
Tipo: Text
Ano: 2019
URL: https://archimer.ifremer.fr/doc/00485/59662/62721.pdf

New short peptaibols from a marine Trichoderma strain
Provedor de dados: 5
Autores: Mohamed Benkada, M; Montagu, M; Biard, J; Mondeguer, Florence; Verite, P; Dalgalarrondo, M; Bissett, J; Pouchus, Y.
The production of peptaibols by a marine-related Trichoderma longibrachiatum strain was studied using electrospray ionisation multiple-stage ion trap mass spectrometry (ESI-MSn-IT) and gas chromatography/electron impact mass spectrometry (GC/EI-MS). Two major groups of peptaibols were identified, those with long sequences (20 amino acids) and others with short sequences (11 amino acids). This paper describes the methodology used to establish the sequences of short peptaibols in a mixture without previous individual separation. Nine peptaibols were identified. Among them, eight are new, namely as trichobrachin A I-IV (Aib(9)-Pro(10) sequence) and as trichobrachin B I-IV (Val(9)-Pro(10) sequence). Original Pro(6)-Val(7) and Val(9)-Pro(10) sequences have to...
Tipo: Text
Palavras-chave: Trichoderma longibrachiatum; Marine fungi; Marine products; Electrospray ionisation multiple stage mass spectrometry ion trap (ESI MSn IT); Short peptaibols.
Ano: 2006
URL: http://archimer.ifremer.fr/doc/2006/publication-1550.pdf

Preliminary metabolomic approach on the bacterial structure community of Haslea ostrearia
Provedor de dados: 5
Autores: Mondeguer, Florence; Lepinay, Alexandra; Capiaux, Hervé; Turpin, Vincent; Lebeau, Thierry.
The marine diatom Haslea ostrearia [1] produces a water-soluble blue-pigment named marennine [2] of economic interest. But the lack of knowledge of the ecological conditions, under which this microalga develops in its natural ecosystem, more especially bacteria H. ostrearia interactions, prevents any optimization of its culture in well-controlled conditions.  The structure of the bacterial community was analyzed by PCR-TTGE before and after the isolation of H. ostrearia cells recovered from 4 localities, to distinguish the relative part of the biotope and the biocenose and eventually to describe the temporal dynamic of the structure of the bacterial community at two time-scales. The differences in genetic fingerprints, more especially high between two H....
Tipo: Text
Palavras-chave: Haslea ostrearia; Marine diatom; Co-culture microalgae; Bacterial community; TTGE; High Resolution Mass Spectrometry; Untargeted metabolomics.
Ano: 2016
URL: http://archimer.ifremer.fr/doc/00342/45368/44863.pdf

First insight on interactions between bacteria and the marine diatom Haslea ostrearia : Algal growth and metabolomic fingerprinting
Provedor de dados: 5
Autores: Lepinay, Alexandra; Turpin, Vincent; Mondeguer, Florence; Grandet-marchant, Quentin; Capiaux, Herve; Baron, Regis; Lebeau, Thierry.
A first insight on the interactions between bacteria isolated from monospecific cultures of the marine diatom Haslea ostrearia and this microalgae is described in this work. From 28 bacterial isolates, the maximal growth rate and the maximal cell concentration were on average 58% and 27% higher (max. 67% for isolate B22). Isolates B5, B10 (both Saccharospirillum sp.) and B22 (Rhodobacter sp.) were the most efficient. The geographical origin of H. ostrearia from which bacteria were isolated had no impact on the algal growth performances, and a given bacterial isolate led to the same algal growth irrespective of the geographical origin of H. ostrearia. To explain the results obtained, a comprehensive integrative strategy was conducted that analyzed the...
Tipo: Text
Palavras-chave: Bacterial selection; Plant-growth-promoting bacteria; Phycosphere; Metabolomics.
Ano: 2018
URL: https://archimer.ifremer.fr/doc/00429/54036/55340.pdf

Effect of food supply on the detoxification in the blue mussel, Mytilus edulis, contaminated by diarrhetic shellfish toxins
Provedor de dados: 5
Autores: Marcaillou-le Baut, Claire; Haure, Joel; Mondeguer, Florence; Courcoux, Anne; Dupuy, Beatrice; Penisson, Christian.
The objective of this study was to identify a possible effect of food on the acceleration of decontamination in blue mussels, Mytilus edulis, containing diarrhetic toxins belonging to the okadaic acid (OA) structural group. An experimental protocol was designed to describe and compare the decontamination kinetics and detoxification rates of naturally OA-contaminated mussels that had either received or not received food for three weeks. The protocol was applied in two trials (in June 2006 and June 2007, called Ker06 and Ker07), conducted one year apart on samples of mussels collected in the same area, at the same season. Okadaic acid (OA), the main lipophilic toxin produced by the toxic alga Dinophysis acuminata, was analysed over the course of the...
Tipo: Text
Palavras-chave: Mussel; Feeding; Digestive gland; Depuration; Okadaic acid; Acyl esters; Marine lipophilic biotoxins; Mass spectrometry.
Ano: 2010
URL: http://archimer.ifremer.fr/doc/00025/13650/10883.pdf

Sélection de workflows adaptés à une analyse métabolomique plus transparente et intégrative
Provedor de dados: 5
Autores: Mondeguer, Florence; Allard, Pierre-marie; Souard, Florence; Elie, Nicolas; Guitton, Yann; Sibat, Manoella; Siano, Raffaele.
During their life cycle, Alexandrium minutum and Scrippsiella donghaienis can produce resistant and revivable cysts that can accumulate in marine sediments for hundreds of years. Our working hypothesis assumes that these two genera have "recorded" their adaptation to ecosystem changes in these cells preserved in the form of cysts. From these revived cysts, toxic and non-toxic dinoflagellate cultures (Alexandrium minutum and Scrippsiella donghaienis) were analyzed by a metabolomic approach to investigate the possible adaptive responses of phytoplankton to these changes in coastal ecosystems. The strains were obtained from isotopically dated sediments, 1986 and 1996 for "ancient" and 2006 for "modern". In total, 84 samples were obtained. Each experimental...
Tipo: Text
Ano: 2019
URL: https://archimer.ifremer.fr/doc/00498/60941/64339.pdf

Validation d’un procédé automatisé d’extraction sur phase solide de glandes digestives de moules pour l’identification et la quantification des dinophysistoxines en LC/ESI/SM2 par piégeage d’ions quadripolaire
Provedor de dados: 5
Autores: Mondeguer, Florence; Mestres, Gilberte; Rouland, Caroline; Montagu, Monique; Maillols, Hélène.
This report presents a new extraction method of the dinophysistoxins (DTXs), confirmed by quantification using high-performance liquid chromatography coupled to mass spectrometry with an ion trap and electro spray interface (HPLC/ESI/MS2). The method originality consists on the adaptation of DTXs basic extraction procedure (liquid/ liquid) to a solid phase extraction (SPE) via a robotic station: ASPEC XLi The parameters of the automatization procedure were optimized to obtain the best DTXs recovery rate. These improvements were loaded with digestive gland mussel homogenat realized on a silica cartridge SPE, activated in hexane/chloroform (50:50), washed with hexane/chloroform (50:50) and extracted by an elution gradient (chloroform methanol (65:35) and...
Tipo: Text
Palavras-chave: Toxines; Intoxication des coquillages; Dinophysistoxines; Acide okadaïque; Dinophysistoxine-1; Méthode alternative; Extraction sur phase solide; Automatisation; Couplage CLHP/ESI/SM2 par piège d’ions.; Toxins; Shellfish poisoning; Dinophysistoxins; Okadaic acid; Dinophysistoxin-1; Alternative method; Solid phase extraction; Automation; Liquid chromatography coupled ion trap.
Ano: 2003
URL: http://archimer.ifremer.fr/doc/00342/45270/44724.pdf

Metabolomic Analysis of Marine Microalgae Using High Resolution Mass Spectrometry for Taxonomic Comparisons and Screening of Marine Biotoxins
Provedor de dados: 5
Autores: Hess, Philipp; Mondeguer, Florence; Glauner, Thomas; Wust, Bernard; Sibat, Manoella; Zendong, Suzie Zita; Herrenknecht, Christine; Sechet, Veronique.
Out of the circa 5000 microalgae known, around 100 marine species of unicellular algae have been shown to produce several hundred biotoxins worldwide. Such biotoxins may be harmful to man through consumption of fish and shellfish exposed to such algae or through direct contact. Many official methods aimed at the detection of such toxins had traditionally been based on biological assays, due to the lack of reference compounds. Recently, legislation for shellfish safety in Europe introduced targeted MS screening for lipophilic toxins. Due to globalization of trade and climate change, there is a need to develop methods for untargeted screening to fully protect consumer safety, e.g. LC-HRMS. For this purpose we studied the metabolomes of marine microalgae...
Tipo: Text
Ano: 2013
URL: http://archimer.ifremer.fr/doc/00179/29037/27473.pdf

Bacterial community structure of the marine diatom Haslea ostrearia
Provedor de dados: 5
Autores: Lepinay, Alexandra; Capiaux, Hervé; Turpin, Vincent; Mondeguer, Florence; Baron, Regis; Lebeau, Thierry.
The marine diatom Haslea ostrearia produces a water-soluble blue-pigment named marennine of economic interest (e.g. in aquaculture for the greening of oysters). Up to date the studies devoted to ecological conditions under which this microalga develops never took into account the bacterial-H. ostrearia relationships.  In this study the bacterial community was analysed by PCR-TTGE before and after H. ostrearia isolation cells recovered from 4 localities, to distinguish the relative part of the biotope and the biocenose and eventually to describe the temporal dynamic of the structure of the bacterial community. The bacterial structure of the phycosphere differed strongly from that of the bulk sediment. The similarity between bacteria recovered from the...
Tipo: Text
Ano: 2016
URL: https://archimer.ifremer.fr/doc/00342/45365/44861.pdf