Consulta: creatorFacets:"Soudant, Philippe"
Registros recuperados: 68
Data/hora: 10/06/2024 09:59:48

Correlation between perkinsosis and growth in clams Ruditapes spp.
Provedor de dados: 5
Autores: Dang, Cecile; De Montaudouin, Xavier; Binias, Cindy; Salvo, Flora; Caill-milly, Nathalie; Bald, Juan; Soudant, Philippe.
Perkinsosis is one of the most widespread diseases affecting commercially important species of molluscs globally. We examined the impact of Perkinsus spp. on shell growth at the individual scale in 2 clam species: Ruditapes decussatus from Mundaka Estuary (Spain) and R. philippinarum from Arcachon Bay (France). At Arcachon, 2 contrasting sites in terms of environment and Perkinsus olseni presence were chosen: Arguin (disease-free) and Ile aux Oiseaux (infected site). We monitored the dynamics of perkinsosis over the course of the experiment at Mundaka and Ile aux Oiseaux. Prevalences were high (&gt;70%), and intensities were around 10(5) cells g(-1) wet gills at Ile aux Oiseaux, and 10(6) cells g(-1) at Mundaka. No significant differences in prevalence or...
Tipo: Text
Palavras-chave: Clams; Perkinsus spp.; Perkinsus olseni; Ruditapes philippinarum; Ruditapes decussatus; Growth.
Ano: 2013
URL: https://archimer.ifremer.fr/doc/00166/27733/25951.pdf

Effects of extracellular products from the pathogenic Vibrio aestuarianus strain 01/32 on lethality and cellular immune responses of the oyster Crassostrea gigas
Provedor de dados: 5
Autores: Labreuche, Yannick; Soudant, Philippe; Goncalves, Madeleine; Lambert, Christophe; Nicolas, Jean-louis.
Vibrio aestuarianus strain 01/32 was previously shown to be pathogenic to Crassostrea gigas juveniles. To investigate virulence mechanisms of this pathogen, we studied the toxicity to oysters of its extracellular products (ECPs). ECPs displayed lethality to animals, with a LD50 value of 3.3 mu g/g body weight. To determine the oyster cellular immune responses induced by these ECPs, we further examined in vitro their effects on C. gigas hemocytes, using flow cytometric-based hemocyte assays. Treatment of hemolymph with ECPs caused a significant inhibition of hemocyte phagocytosis and adhesive capabilities. In contrast, the pathway of reactive oxygen species production was enhanced by higher ECP concentrations. Exposure of hemocytes to live bacteria induced...
Tipo: Text
Palavras-chave: Vibrio aestuarianus; ECPs; Crassostrea gigas; ROS production; Adhesion; Phagocytosis; Flow cytometry; Bivalve immunity.
Ano: 2006
URL: http://archimer.ifremer.fr/doc/2006/publication-1035.pdf

Effects of Alexandrium minutum exposure upon physiological and hematological variables of diploid and triploid oysters, Crassostrea gigas
Provedor de dados: 5
Autores: Haberkorn, Hansy; Lambert, Christophe; Le Goic, Nelly; Gueguen, Marielle; Moal, Jeanne; Palacios, Elena; Lassus, Patrick; Soudant, Philippe.
The effects of an artificial bloom of the toxin-producing dinoflagellate, Alexandrium minutum, upon physiological parameters of the Pacific oyster, Crassostrea gigas, were assessed. Diploid and triploid oysters were exposed to cultured A. minutum and compared to control diploid and triploid oysters fed T. Isochrysis. Experiments were repeated twice, in April and mid-May 2007, to investigate effects of maturation stage on oyster responses to A. minutum exposure. Oyster maturation stage, Paralytic Shellfish Toxin (PST) accumulation, as well as several digestive gland and hematological variables, were assessed at the ends of the exposures. In both experiments, triploid oysters accumulated more PSTs (approximately twice) than diploid oysters. Significant...
Tipo: Text
Palavras-chave: Oysters; Ploidy; Physiology; Harmful-algal bloom; Alexandrium minutum; PST accumulation.
Ano: 2010
URL: http://archimer.ifremer.fr/doc/00003/11378/7988.pdf

Effect of Salinity and Nitrogen Form in Irrigation Water on Growth, Antioxidants and Fatty Acids Profiles in Halophytes Salsola australis, Suaeda maritima, and Enchylaena tomentosa for a Perspective of Biosaline Agriculture
Provedor de dados: 5
Autores: Certain, Cassandre; Della Patrona, Luc; Gunkel-grillon, Peggy; Leopold, Audrey; Soudant, Philippe; Le Grand, Fabienne.
Cultivation of salt-tolerant crops help to face to irreversible global salinization of freshwater and soils. In New-Caledonia, three halophytes are candidates for saline crops, Salsola australis R.Br., Suaeda maritima (L.) Dumort and Enchylaena tomentosa R.Br. Their success and quality depend yet on availabilities of salinity and essential nutrients in agrosystems. So, we investigated effects of three salinities, i.e., control moderate and high, and five nitrogen ratios, i.e., 100:0, 75:25, 50:50, 25:75 or 0:100 NO3−-N:NH4+-N ratio on their growth and functional value for fatty acids and antioxidants. Results show that the leaf fatty acid and antioxidant profiles of species, emphasize their good potential to become functional crop products, based on...
Tipo: Text
Palavras-chave: Halophyte; Salsola australis; Suaeda maritima; Enchylaena tomentosa; Salt tolerance; Nitrogen form; Fatty acid; Phenolic compounds; Antioxidant activity.
Ano: 2021
URL: https://archimer.ifremer.fr/doc/00682/79411/81960.pdf

Involvement of Mitochondrial Activity and OXPHOS in ATP Synthesis During the Motility Phase of Spermatozoa in the Pacific Oyster, Crassostrea gigas
Provedor de dados: 5
Autores: Boulais, Myrina; Soudant, Philippe; Le Goic, Nelly; Quere, Claudie; Boudry, Pierre; Suquet, Marc.
In the Pacific oyster, spermatozoa are characterized by a remarkably long movement phase (i.e., over 24 h) sustained by a capacity to maintain intracellular ATP level. To gain information on oxidative phosphorylation (OXPHOS) functionality during the motility phase of Pacific oyster spermatozoa, we studied 1) changes in spermatozoal mitochondrial activity, that is, mitochondrial membrane potential (MMP), and intracellular ATP content in relation to motion parameters and 2) the involvement of OXPHOS for spermatozoal movement using carbonyl cyanide m-chlorophenyl hydrazone (CCCP). The percentage of motile spermatozoa decreased over a 24 h movement period. MMP increased steadily during the first 9 h of the movement phase and was subsequently maintained at a...
Tipo: Text
Palavras-chave: Crassostrea gigas; Intracellular ATP content; Mitochondrial membrane potential; Oxidative phosphorylation; Sperm motility.
Ano: 2015
URL: https://archimer.ifremer.fr/doc/00303/41376/40666.pdf

Recommendations for evaluation of the health status in cultured and wild shellfish: Perkinsus olseni infestation in clams as an example
Provedor de dados: 5
Autores: Miossec, Laurence; Arzul, Isabelle; Garcia, Celine; Soudant, Philippe; Francois, Cyrille; Leite, R. B.; Cancela, M. L.; De Blas, I.
Infectious diseases in exploited shellfish population cause economical problems world-wide. The characteristics of the disease in the population -i.e. origin, frequency, distribution, development- need to be well known to set up appropriate measures for protection and restoration of shellfish population health. The investigation of disease in a population is the basis of epidemiology. Quantitative investigations include studies, survey, surveillance with specific sampling strategies according to the objectives. European clams (Ruditapes decussatus) and Manila clams (Ruditapes philippinarum), two commercially valuable species, are infected by the protozoan Perkinsus olseni. This pathogen has been associated with epizootic outbreaks involving in heavy...
Tipo: Text
Palavras-chave: Recommendations; Epidemiology; Aquatic animal diseases; Pathology; Perkinsus olseni.
Ano: 2005
URL: http://archimer.ifremer.fr/doc/2005/acte-3326.pdf

TOPHYPAC. Tolérance des communautés phytoplanctoniques aux phytosanitaires dans le panache de la Charente. Programme Évaluation et réduction des risques liés à l’utilisation des Pesticides
Provedor de dados: 5
Autores: Stachowski-haberkorn, Sabine; Guesdon, Stephane; Bechemin, Christian; Chiffoleau, Jean-francois; Brach-papa, Christophe; Soudant, Philippe; Beker, Beatriz; Jadas-hécart, Alain.
TOPHYPAC is a field study that was conducted in the Charente river estuary (Marennes-Oléron bay). The main goal was to assess the possible impact of chemical contamination with copper and pesticides on phytoplankton communities. Physical, chemical (nutrients, metals and pesticides) and biological (phytoplankton community) parameters were monitored in the field during three years, from 2011 to 2014. In 2012 and 2013, field sampling was coupled with experimental exposure of phytoplankton communities to copper and to an herbicide cocktail, after transportation to the lab: the effects were assessed using photosynthesis endpoint and cellular densities. TOPHYPAC allowed to set the framework of Charente estuary contamination with pesticides: herbicides glyphosate...
Tipo: Text
Palavras-chave: Continuum eau douce/eau côtière; Pesticides; Métaux; Communautés phytoplanctoniques; Efficacité de photosynthèse; PICT; Tolérance; Cytométrie en flux; Toxicité chronique; Freshwater/coastal water continuum; Pesticides; Metals; Phytoplankton communities; Photosynthesis efficiency; PICT; Tolerance; Flow cytometry; Chronic toxicity.
Ano: 2014
URL: http://archimer.ifremer.fr/doc/00300/41115/40289.pdf

Laboratory conditioning modifies properties of gills mitochondria from the Pacific oyster Crassostrea gigas
Provedor de dados: 5
Autores: Dudognon, Tony; Guderley, Helga; Quere, Claudie; Soudant, Philippe; Racotta, Ilie; Kraffe, Edouard.
Although laboratory experiments allow greater control of environmental conditions than field studies, they have several drawbacks. To analyze physiological responses to forcing environmental variables, experimental conditions should mimic natural conditions as closely as possible. For filter-feeding organisms in particular, diet quality and quantity is one of the environmental parameters that can differ markedly between experimental and field conditions. In the hatchery, Pacific oysters, Crassostrea gigas, commonly show good physiological performance and growth on a mixed algal diet of Tisochrysis lutea, formerly Isochrysis aff. galbana clone Tahiti (T-Iso), and Chaetoceros calcitrans, presumably as it provides a good supply of essential polyunsaturated...
Tipo: Text
Ano: 2015
URL: https://archimer.ifremer.fr/doc/00266/37756/36065.pdf

Toxic dinoflagellates (Alexandrium fundyense and A-catenella) have minimal apparent effects on oyster hemocytes
Provedor de dados: 5
Autores: Hegaret, Hélène; Wikfors, Gary H.; Soudant, Philippe; Lambert, Christian; Shumway, Sandra E.; Berard, Jean-baptiste; Lassus, Patrick.
The possible effect of Alexandrium spp. containing paralytic shellfish poisoning (PSP) toxins on the hemocytes of oysters was tested experimentally. In one trial, eastern oysters, Crassostrea virginica Gmelin, were exposed to bloom concentrations of the sympatric dinoflagellate, Alexandrium fundyense Balech, alone and in a mixture with a non-toxic diatom, Thalassiosira weissflogii (Grun) Fryxell et Hasle. Subsequently, another experiment exposed Pacific oysters, Crassostrea gigas Thunberg, to a mixed suspension of the sympatric, toxic species Alexandrium catenella (Whedon et Kofoid) Balech, with T. weissflogii. Measurements of numbers of oyster hemocytes, percentages of different cell types, and functions (phagocytosis, reactive oxygen species (ROS)...
Tipo: Text
Ano: 2007
URL: http://archimer.ifremer.fr/doc/2007/publication-3328.pdf

Exposure of marine mussels Mytilus spp. to polystyrene microplastics: Toxicity and influence on fluoranthene bioaccumulation
Provedor de dados: 5
Autores: Paul-pont, Ika; Lacroix, Camille; Gonzalez Fernandez, Carmen; Hegaret, Helene; Lambert, Christophe; Le Goic, Nelly; Frere, Laura; Cassone, Anne-laure; Sussarellu, Rossana; Fabioux, Caroline; Guyomarch, Julien; Albentosa, Marina; Huvet, Arnaud; Soudant, Philippe.
The effects of polystyrene microbeads (micro-PS; mix of 2 and 6 μm; final concentration: 32 μg L−1) alone or in combination with fluoranthene (30 μg L−1) on marine mussels Mytilus spp. were investigated after 7 days of exposure and 7 days of depuration under controlled laboratory conditions. Overall, fluoranthene was mostly associated to algae Chaetoceros muelleri (partition coefficient Log Kp = 4.8) used as a food source for mussels during the experiment. When micro-PS were added in the system, a fraction of FLU transferred from the algae to the microbeads as suggested by the higher partition coefficient of micro-PS (Log Kp = 6.6), which confirmed a high affinity of fluoranthene for polystyrene microparticles. However, this did not lead to a modification...
Tipo: Text
Palavras-chave: Microplastics; Fluoranthene; Mussel; Depuration; Oxidative system.
Ano: 2016
URL: https://archimer.ifremer.fr/doc/00344/45502/45848.pdf

Socio-economic impact of microplastics in the 2 Seas, Channel and France Manche Region. An initial risk assessment
Provedor de dados: 5
Autores: Van Der Meulen, Md; De Vriese, L; Lee, J; Maes, T; Van Dalfsen, Ja; Huvet, Arnaud; Soudant, Philippe; Robbens, J; Vethaak, Ad.
This report has been produced under the Interreg IVa project MICRO. We would like to thank the Joint Technical Secretariat of Interreg, the Dutch Ministry of Infrastructure and the Environment for co-financing the work conducted in this project. Also, the Institute for Environmental Studies of the VU University in Amsterdam and Stichting de Zeeschelp in Kamperland, many thanks for your analyses and experimental support and advice. Many thanks to all of the researchers who worked on this project, especially Christophe Lambert, David Mazurais, Rosanna Sussarellu, Ika Paul-Pont, Laura Frere, Anne-Laure Cassone, Dana Stuparu, Frank Kleissen, Ghada El Serafy, Sara Maes, Mattias Bossaer, Bavo De Witte, Johanna Gauquie, Caroline De Tender, Kevin Vanhalst.
Tipo: Text
Ano: 2014
URL: http://archimer.ifremer.fr/doc/00287/39834/38359.pdf

New insights into the seasonal feeding ecology of Pecten maximus using pigments, fatty acids and sterols analyses
Provedor de dados: 5
Autores: Lavaud, Romain; Artigaud, Sebastien; Le Grand, Fabienne; Donval, Anne; Soudant, Philippe; Flye-sainte-marie, Jonathan; Strohmeier, Tore; Strand, Oivind; Leynaert, Aude; Beker, Beatriz; Chatterjee, Arnab; Jean, Fred.
We combined the use of pigments, fatty acids and sterols as biomarkers of the seasonal variation in food sources of the great scallop Pecten maximus. From March to October 2011, on a biweekly to twice-weekly basis, scallops and seawater from the water column and the water-sediment interface were collected in the Bay of Brest (Brittany, France). Pigment compositions in the seawater and in the stomach and rectum content of the scallops were analyzed by HPLC. Fatty acids and sterols from digestive gland (DG) tissue were analyzed by gas chromatography. Potential relationships between the temporal proportion of each marker in the environment and in the digestive tract were tested using multivariate analysis. Proportions of diatoms and Dinophyceae biomarkers...
Tipo: Text
Palavras-chave: Trophic ecology; Food sources; Pigments; Fatty acids; Trophic marker; Phytoplankton; Pecten maximus.
Ano: 2018
URL: https://archimer.ifremer.fr/doc/00431/54244/55772.pdf

Nanoplastics impaired oyster free living stages, gametes and embryos
Provedor de dados: 5
Autores: Tallec, Kevin; Huvet, Arnaud; Di Poi, Carole; Gonzalez-fernandez, Carmen; Lambert, Christophe; Petton, Bruno; Le Goic, Nelly; Berchel, Mathieu; Soudant, Philippe; Paul-pont, Ika.
In the marine environment, most bivalve species base their reproduction on external fertilization. Hence, gametes and young stages face many threats, including exposure to plastic wastes which represent more than 80% of the debris in the oceans. Recently, evidence has been produced on the presence of nanoplastics in oceans, thus motivating new studies of their impacts on marine life. Because no information is available about their environmental concentrations, we performed dose-response exposure experiments with polystyrene particles to assess the extent of micro/nanoplastic toxicity. Effects of polystyrene with different sizes and functionalization (plain 2-μm, 500-nm and 50-nm; COOH-50 nm and NH2-50 nm) were assessed on three key reproductive steps...
Tipo: Text
Palavras-chave: Oyster; Embryos; Gametes; Microplastics; Nanoplastics.
Ano: 2018
URL: https://archimer.ifremer.fr/doc/00453/56419/58090.pdf

Identification of Polyunsaturated Fatty Acids Synthesis Pathways in the Toxic Dinophyte Alexandrium minutum Using 13C-Labelling
Provedor de dados: 5
Autores: Remize, Marine; Planchon, Frederic; Loh, Ai Ning; Le Grand, Fabienne; Lambert, Christophe; Bideau, Antoine; Bidault, Adeline; Corvaisier, Rudolph; Volety, Aswani; Soudant, Philippe.
The synthetic pathways responsible for the production of the polyunsaturated fatty acids 22:6n-3 and 20:5n-3 were studied in the Dinophyte Alexandrium minutum. The purpose of this work was to follow the progressive incorporation of an isotopic label (13CO2) into 11 fatty acids to better understand the fatty acid synthesis pathways in A. minutum. The Dinophyte growth was monitored for 54 h using high-frequency sampling. A. minutum presented a growth in two phases. A lag phase was observed during the first 30 h of development and had been associated with the probable temporary encystment of Dinophyte cells. An exponential growth phase was then observed after t30. A. minutum rapidly incorporated 13C into 22:6n-3, which ended up being the most 13C-enriched...
Tipo: Text
Palavras-chave: PUFA synthesis; 22:6n-3; DHA; PKS pathway; Dinophyte; Alexandrium minutum; Encystment.
Ano: 2020
URL: https://archimer.ifremer.fr/doc/00654/76562/77688.pdf

Colonization of polystyrene microparticles by Vibrio crassostreae: light and electron microscopic investigation
Provedor de dados: 5
Autores: Foulon, Valentin; Le Roux, Frederique; Lambert, Christophe; Huvet, Arnaud; Soudant, Philippe; Paul-pont, Ika.
Microplastics collected at sea harbour a high diversity of microorganisms including some Vibrio genus members, raising questions about the role of microplastics as a novel ecological niche for potentially pathogenic microorganisms. In the present study we investigated the adhesion dynamics of Vibrio crassostreae on polystyrene microparticles (micro-PS) using electronic and fluorescence microscopy techniques. Micro-PS were incubated with bacteria in different media (Zobell culture medium and artificial seawater) with or without natural marine aggregates. The highest percentage of colonised particles (38-100%) was observed in Zobell culture medium, which may be related to nutrient availability for production of pili and exopolysaccharide adhesion structures....
Tipo: Text
Ano: 2016
URL: https://archimer.ifremer.fr/doc/00351/46210/45908.pdf

Changes in biochemical and hemocyte parameters of the pacific oysters Crassostrea gigas fed T-Iso supplemented with lipid emulsions rich in eicosapentaenoic acid
Provedor de dados: 5
Autores: Delaporte, Maryse; Chu, Fu-lin; Langdon, Chris; Moal, Jeanne; Lambert, Christophe; Samain, Jean-francois; Soudant, Philippe.
The aim of this study was to assess the effect of dietary eicosapentaenoic acid (20:5n-3) on hemocyte parameters such as hemocyte concentration, phagocytosis, and non-stimulated reactive oxygen species (ROS) production in Pacific oysters Crassostrea gigas, as well on proximate biochemical and fatty acid compositions. One-year-old oysters (C. gigas) were fed T-Isochrysis aff. galbana(T-Iso), which is low in 20:5n-3, either alone or with supplements of a lipid emulsion rich in 20:5n-3 at 1%, 10% or 50% (dry weight of the algal ration) for up to 7 weeks. Changes in gill fatty acid composition demonstrated that the lipid emulsion was well ingested by oysters during the dietary conditioning. Biochemical analysis indicated that oysters fed supplements of 50%...
Tipo: Text
Palavras-chave: Polyunsaturated fatty acids; Immunology; Hemocytes; Eicosapentaenoic acid 20 : 5n 3; Crassostrea gigas; Bivalves.
Ano: 2007
URL: http://archimer.ifremer.fr/doc/2007/publication-2604.pdf

Exposure to the toxic dinoflagellate Alexandrium catenella modulates juvenile oyster Crassostrea gigas hemocyte variables subjected to different biotic conditions
Provedor de dados: 5
Autores: Lassudrie, Malwenn; Soudant, Philippe; Nicolas, Jean-louis; Miner, Philippe; Le Grand, Jacqueline; Lambert, Christophe; Le Goic, Nelly; Hegaret, Helene; Fabioux, Caroline.
The Pacific oyster Crassostrea gigas is an important commercial species cultured throughout the world. Oyster production practices often include transfers of animals into new environments that can be stressful, especially at young ages. This study was undertaken to determine if a toxic Alexandrium bloom, occurring repeatedly in French oyster beds, could modulate juvenile oyster cellular immune responses (i.e. hemocyte variables). We simulated planting on commercial beds by conducting a cohabitation exposure of juvenile, “specific pathogen-free” (SPF) oysters (naïve from the environment) with previously field-exposed oysters to induce interactions with new microorganisms. Indeed, toxic Alexandrium spp. exposures have been reported to modulate bivalve...
Tipo: Text
Palavras-chave: Crassostrea gigas; Alexandrium; Harmful algal blooms; Hemocyte; Microbial challenge.
Ano: 2016
URL: https://archimer.ifremer.fr/doc/00314/42523/41894.pdf

BABE : Comparaison des sites de Ronce et Baie de Veys, incidence sur la reproduction et les mortalités : Ecologie côtière, mortalités, croissance, environnement - Physiologie - Immunologie
Provedor de dados: 5
Autores: Soletchnik, Patrick; Le Moine, Olivier; Faury, Nicole; Guilpain, Patrice; Geairon, Philippe; Razet, Daniel; Seugnet, Jean-luc; Robert, Stephane; Ropert, Michel; Simonne, Charlotte; Hugonnet, Virginie; Moal, Jeanne; Pouvreau, Stephane; Huvet, Arnaud; Samain, Jean-francois; Lambert, Christophe; Soudant, Philippe; Frouel, Stephane; Choquet, Gwenaelle; Delaporte, Maryse; Paillard, Christine.
Four laboratories are involved in this multidisciplinary study: the Conchological Laboratory of Normandie (LCN), the Invertebrates Physiology Laboratory (LPI), the Université Bretagne Occidentale (LEMAR IHP) and the Conchological Laboratory of Poitou-Charentes (LCPC). The part of the study which is presented here (thematics "Coastal ecology") was produced in collaboration with the LCN. The data on the Bay of Veys was collected by Michel Ropert. This study aims at observing the "sites" effect on mortality and on the general biology of the animal, as well as measuring some environmental elements (e.g. water temperature, etc.). The geographical sites are Gefosse in the Bay of Veys (East Cotentin) and the Ronce bank in the south of the Marennes Oléron Bay. The...
Tipo: Text
Palavras-chave: Immunologie; Physiologie; Paramètres environnementaux; Croissance; Ecologie côtière; Baies des Veys Cotentin; Ronce   Charente Maritime; Comparaison sites; Reproduction; Mortalités; Crassostrea gigas; Huîtres.
Ano: 2002
URL: http://archimer.ifremer.fr/doc/2002/acte-3405.pdf

Cellular and biochemical responses of the oyster Crassostrea gigas to controlled exposures to metals and Alexandrium minutum
Provedor de dados: 5
Autores: Haberkorn, Hansy; Lambert, Christophe; Le Goic, Nelly; Quere, Claudie; Bruneau, A; Riso, Ricardo; Auffret, Michel; Soudant, Philippe.
Effects of simultaneous exposure of Pacific oyster, Crassostrea gigas, to both a harmful dinoflagellate that produces Paralytic Shellfish Toxins (PST), Alexandrium minutum, and cadmium (Cd) and copper (Cu), were assessed. Oysters were exposed to a mix of Cd-Cu with two different diets (i.e. A. minutum or Tisochrysis lutea) and compared to control oysters fed A. minutum or T. lutea, respectively, without metal addition. Metals and PST accumulations, digestive gland lipid composition, and cellular and biochemical hemolymph variables were measured after 4 days of exposure. Oysters exposed to Cd-Cu accumulated about thirty-six times less PSTs than oysters exposed to A. minutum alone. Exposure to Cd-Cu induced significant changes in neutral lipids (increase in...
Tipo: Text
Palavras-chave: Harmful algae; Metals; Oysters; Toxin accumulation; Physiological effects.
Ano: 2014
URL: http://archimer.ifremer.fr/doc/00169/28071/26286.pdf

Interactions between polystyrene microplastics and marine phytoplankton lead to species-specific hetero-aggregation
Provedor de dados: 5
Autores: Long, Marc; Paul-pont, Ika; Hegaret, Helene; Moriceau, Brivaela; Lambert, Christophe; Huvet, Arnaud; Soudant, Philippe.
To understand the fate and impacts of microplastics (MP) in the marine ecosystems, it is essential to investigate their interactions with phytoplankton as these may affect MP bioavailability to marine organisms as well as their fate in the water column. However, the behaviour of MP with marine phytoplanktonic cells remains little studied and thus unpredictable. The present study assessed the potential for phytoplankton cells to form hetero-aggregates with small micro-polystyrene (micro-PS) particles depending on microalgal species and physiological status. A prymnesiophycea, Tisochrysis lutea, a dinoflagellate, Heterocapsa triquetra, and a diatom, Chaetoceros neogracile, were exposed to micro-PS (2 μm diameter; 3.96 μg L−1) during their growth culture...
Tipo: Text
Palavras-chave: Polystyrene; Microplastic; Aggregates; Microalgae; Marine; Phytoplankton.
Ano: 2017
URL: https://archimer.ifremer.fr/doc/00389/50016/50735.pdf

A rapid quantitative fluorescence-based bioassay to study allelochemical interactions from Alexandrium minutum
Provedor de dados: 5
Autores: Long, Marc; Tallec, Kevin; Soudant, Philippe; Lambert, Christophe; Le Grand, Fabienne; Sarthou, Geraldine; Jolley, Dianne; Hegaret, Helene.
Harmful microalgal blooms are a threat to aquatic organisms, ecosystems and human health. Toxic dinoflagellates of the genus Alexandrium are known to produce paralytic shellfish toxins and to release bioactive extracellular compounds (BECs) with potent cytotoxic, hemolytic, ichtyotoxic and allelopathic activity. Negative allelochemical interactions refer to the chemicals that are released by the genus Alexandrium and that induce adverse effects on the physiology of co-occurring protists and predators. Releasing BECs gives the donor a competitive advantage that may help to form dense toxic blooms of phytoplankton. However BECs released by Alexandrium minutum are uncharacterized and it is impossible to quantify them using classical chemical methods....
Tipo: Text
Palavras-chave: Harmful algal bloom; Alexandrium; Allelopathy; Cytotoxicity; PAM fluorometry; Bioassay.
Ano: 2018
URL: https://archimer.ifremer.fr/doc/00453/56424/58116.pdf

Interaction between toxic dinoflagellate Alexandrium catenella exposure and disease associated with herpesvirus OsHV-1μVar in Pacific oyster spat Crassostrea gigas
Provedor de dados: 5
Autores: Lassudrie, Malwenn; Soudant, Philippe; Nicolas, Jean-louis; Fabioux, Caroline; Lambert, Christophe; Miner, Philippe; Le Grand, Jacqueline; Petton, Bruno; Hegaret, Helene.
Blooms of toxic dinoflagellates can co-occur with mass mortality events associated with herpesvirus OsHV-1 μVar infection that have been decimating Pacific oyster Crassostrea gigas spat and juveniles every summer since 2008 in France. This study investigated the possible effect of a harmful dinoflagellate, Alexandrium catenella, a producer of Paralytic Shellfish Toxins (PSTs), upon the oyster spat–herpesvirus interaction. Oyster spat from a hatchery were challenged by cohabitation with oysters contaminated in the field with OsHV-1 μVar and possibly other pathogens. Simultaneously, the oysters were exposed to cultured A. catenella. Infection with OsHV-1 μVar and PST accumulation were measured after 4 days of experimental exposure.  Exposure to Alexandrium...
Tipo: Text
Palavras-chave: Crassostrea gigas; OsHV-1 mu Var; Harmful algal blooms; Alexandrium; Host-pathogen interaction; PST accumulation.
Ano: 2015
URL: https://archimer.ifremer.fr/doc/00269/38000/36101.pdf

Surface functionalization determines behavior of nanoplastic solutions in model aquatic environments
Provedor de dados: 5
Autores: Tallec, Kevin; Blard, Océane; González-fernández, Carmen; Brotons, Guillaume; Berchel, Mathieu; Soudant, Philippe; Huvet, Arnaud; Paul-pont, Ika.
Plastic debris are classified as a function of their size and recently a new class was proposed, the nanoplastics. Nano-sized plastics have a much greater surface area to volume ratio than larger particles, which increases their reactivity in aquatic environment, making them potentially more toxic. Only little information is available about their behavior whereas it crucially influences their toxicity. Here, we used dynamic light scattering (DLS) to explore the influence of environmental factors (fresh- and saltwater, dissolved organic matter) on the behavior (surface charge and aggregation state) of three different nano-polystyrene beads (50 nm), with (i) no surface functionalization (plain), (ii) a carboxylic or (iii) an amine functionalization. Overall,...
Tipo: Text
Palavras-chave: Nanoplastic; Dynamic light scattering; Behavior; Aggregation; Salinity; Organic matter.
Ano: 2019
URL: https://archimer.ifremer.fr/doc/00485/59652/62684.pdf

Effects of growth phase and nitrogen limitation on biochemical composition of two strains of Tisochrysis lutea
Provedor de dados: 5
Autores: Da Costa, Fiz; Le Grand, Fabienne; Quere, Claudie; Bougaran, Gael; Cadoret, Jean-paul; Robert, Rene; Soudant, Philippe.
Standard and mutant Tisochrysis lutea strains were grown in batch culture for 10 days under nitrogen (N)-replete and N-reduced conditions to determine the effects of N supply in culture medium and growth phase on microalgal physiology and biochemistry. These two T. lutea strains were compared in terms of growth, morphology, associated free-living bacterial community, viability, intracellular lipid content (as measured by Bodipy staining), chlorophyll autofluorescence, and biochemical composition, with a focus on lipid class and fatty acid compositions. The standard strain (T) reached higher cell counts regardless of N supply in culture medium. In both T. lutea strains, microalgal final cell density was significantly lower in N-reduced medium. Carbohydrates...
Tipo: Text
Palavras-chave: Tisochrysis lutea; Nitrogen limitation; Growth phase; Flow cytometry; Fatty acids; Lipid classes.
Ano: 2017
URL: http://archimer.ifremer.fr/doc/00399/51074/51936.pdf

The influence of dietary supplementation of arachidonic acid on prostaglandin production and oxidative stress in the Pacific oyster Crassostrea gigas
Provedor de dados: 5
Autores: Seguineau, Catherine; Racotta, Ilie; Palacios, Elena; Delaporte, Maryse; Moal, Jeanne; Soudant, Philippe.
In a previous study, dietary supplementation with arachidonic acid (ARA) to oysters Crassostrea gigas increased haemocyte numbers, phagocytosis, and production of reactive oxygen species level (ROS) by haemocytes (Delaporte et al., 2006). To assess if the observed stimulation of these cellular responses resulted from changes of ARA-related prostaglandin (PG) production, we analysed prostaglandin E2 metabolite (PGEM) content on the same oysters fed three levels of ARA. Dietary supply of polyunsaturated fatty acids (PUFA) could also induce an oxidative stress that could similarly increase cellular responses; therefore, two indicators of oxidative stress were analysed: peroxidation level and antioxidant defence status. Together the observed positive...
Tipo: Text
Palavras-chave: Prostaglandins; N-6 unsaturated fatty acids; Lipid peroxidation; Antioxidants; ROS production.
Ano: 2011
URL: http://archimer.ifremer.fr/doc/00040/15103/12785.pdf

Effects of copper on the dinoflagellate Alexandrium minutum and its allelochemical potency
Provedor de dados: 5
Autores: Long, Marc; Holland, Aleicia; Planquette, Helene; Gonzalez Santana, David; Whitby, Hannah; Soudant, Philippe; Sarthou, Geraldine; Hégaret, Helene; Jolley, Dianne F.
The dinoflagellate Alexandrium minutum produces toxic compounds, including paralytic shellfish toxins, but also some unknown extracellular toxins. Although copper (Cu) is an essential element, it can impair microalgal physiology and increase their toxic potency. This study investigated the effect of different concentrations of dissolved Cu (7 nM, 79 nM and 164 nM) on A. minutum allelochemical potency, here defined as negative effects of a protist on competing protists through the release of chemicals. This was studied in relation to its physiology. The effects of Cu were assessed on A. minutum growth, reactive oxygen species level, photosynthesis proxies, lipid metabolism, exudation of dissolved organic compounds, allelochemical potency and on the...
Tipo: Text
Palavras-chave: Alexandrium; Copper; Toxicity; Allelopathy; Physiology; Exudate.
Ano: 2019
URL: https://archimer.ifremer.fr/doc/00484/59612/62629.pdf

State of art and best practices for fatty acid analysis in aquatic sciences
Provedor de dados: 5
Autores: Couturier, Lydie; Michel, Loic; Amaro, Teresa; Budge, Suzanne M; Da Costa, Elisabete; De Troch, Marleen; Di Dato, Valeria; Fink, Patrick; Giraldo, Carolina; Le Grand, Fabienne; Loaiza, Iván; Mathieu-resuge, Margaux; Nichols, Peter D; Parrish, Christopher C; Sardenne, Fany; Vagner, Marie; Pernet, Fabrice; Soudant, Philippe; Browman, Howard.
Determining the lipid content and fatty acid (FA) composition of aquatic organisms has been of major interest in trophic ecology, aquaculture, and nutrition for over half a century. Although protocols for lipid analysis are well-described, their application to aquatic sciences often requires modifications to adapt to field conditions and to sample type. Here, we present the current state of knowledge of methods dedicated to both marine and freshwater lipid analyses, from sampling to data treatment. We review: (i) sample preservation, storage and transport protocols, and their effects on lipids, (ii) lipid extraction, separation of polar and neutral lipids, derivatization, and detection methods, and (iii) available tools for the statistical analysis of FA...
Tipo: Text
Palavras-chave: Aquatic nutrition; Biomarkers; Fatty acids; Marine and freshwater lipids; Methods; Recommended practices.
Ano: 2020
URL: https://archimer.ifremer.fr/doc/00651/76279/77252.pdf

Effect of environmental and nutritive conditionings on defense mechanisms of oyster Crassostrea gigas during an annual cycle
Provedor de dados: 5
Autores: Delaporte, Maryse; Moal, Jeanne; Soudant, Philippe; Lambert, Christophe; Pouvreau, Stephane; Enriquez, Martha; Degremont, Lionel; Soletchnik, Patrick; Gagnaire, Beatrice; Ropert, Michel.
In the frame of MOREST project, a common biological material, resulting of a mixture of different families produced in experimental hatchery, was reared in two different environmental fields : Normandy and Charente. Concomitantly, a pool was conditioned at the Ifremer Argenton hatchery with three different algae levels : 4%, 8% and 12% of algal dry weight per oyster dry weight. During the experiments, five immune parameters were studied in parallel with survival rate and reproductive status (stages and intensity). Site location, seasonal variations and experimental diet level clearly influenced oyster immune parameters. Haemocyte counts were higher for oysters reared in Normandy than those reared in Charente and in hatchery. Granulocyte percentage was...
Tipo: Text
Palavras-chave: Defense mechanisms; Nutrition; Seasonal variations; Physiology; Crassostrea gigas; Pacific oysters.
Ano: 2003
URL: http://archimer.ifremer.fr/doc/2003/acte-3500.pdf

Essential Fatty Acid Assimilation and Synthesis in Larvae of the Bivalve Crassostrea gigas
Provedor de dados: 5
Autores: Da Costa Gonzalez, Fiz; Robert, Rene; Quere, Claudie; Wikfors, Gary H.; Soudant, Philippe.
Essential fatty acids (EFA) are important for bivalve larval survival and growth. The purpose of this study was to quantitatively assess for the first time through a mass-balance approach dietary EFA incorporation and synthesis within Crassostrea gigas larvae. A first experiment was carried out using two microalgae, Tisochrysis lutea (T) and Chaetoceros neogracile (Cg), as mono- and bi-specific diets. A second experiment using a similar design was performed to confirm and extend the results obtained in the first. Flow-through larval rearing was used for accurate control of food supply and measurement of ingestion. Non-methylene-interrupted fatty acids were synthetized from precursors supplied in the diet: 16:1n-7 and 18:1n-9, mediated by Delta 5...
Tipo: Text
Palavras-chave: Fatty acid; Larvae; Lipids; Metabolism; Oyster; Synthesis.
Ano: 2015
URL: https://archimer.ifremer.fr/doc/00268/37962/36086.pdf

Study of Synthesis Pathways of the Essential Polyunsaturated Fatty Acid 20:5n-3 in the Diatom Chaetoceros Muelleri Using 13C-Isotope Labeling
Provedor de dados: 5
Autores: Remize, Marine; Planchon, Frederic; Loh, Ai Ning; Le Grand, Fabienne; Bideau, Antoine; Le Goic, Nelly; Fleury, Elodie; Miner, Philippe; Corvaisier, Rudolph; Volety, Aswani; Soudant, Philippe.
The present study sought to characterize the synthesis pathways producing the essential polyunsaturated fatty acid (PUFA) 20:5n-3 (EPA). For this, the incorporation of 13C was experimentally monitored into 10 fatty acids (FA) during the growth of the diatom Chaetoceros muelleri for 24 h. Chaetoceros muelleri preferentially and quickly incorporated 13C into C18 PUFAs such as 18:2n-6 and 18:3n-6 as well as 16:0 and 16:1n-7, which were thus highly 13C-enriched. During the experiment, 20:5n-3 and 16:3n-4 were among the least-enriched fatty acids. The calculation of the enrichment percentage ratio of a fatty acid B over its suspected precursor A allowed us to suggest that the diatom produced 20:5n-3 (EPA) by a combination between the n-3 (via 18:4n-3) and n-6...
Tipo: Text
Palavras-chave: Synthesis pathway; Diatom; 20:5n-3 (EPA); Chaetoceros muelleri; Acyl-editing mechanism; Compound-specific isotope analysis.
Ano: 2020
URL: https://archimer.ifremer.fr/doc/00630/74257/73887.pdf

Genetic and reproduction strategy in Crassostrea gigas mortality
Provedor de dados: 5
Autores: Moal, Jeanne; Bedier, Edouard; Fleury, Pierre-gildas; Langlade, Aime; Le Coguic, Yvette; Degremont, Lionel; Boudry, Pierre; Le Coz, Jean-rene; Pouvreau, Stephane; Enriquez-diaz, M.; Lambert, Christophe; Quere, Christele; Soudant, Philippe; Samain, Jean-francois.
Bi-parental families were produced in hatchery and tested in the field in 2001. Two sets of 5 families were constituted, selected on their high (R) and low (S) survival. These two sets were reared in Brittany from March to November 2002. Samplings were performed twice a month to obtain data on biometry, survival, reproductive cycle, biochemical composition, adenylate energy charge, hemolymph parameters (ions and defense system) and muscle strength. "R" and "S" oysters exhibited different reproductive effort and spawning strategy. "R" oysters allocated less energy in gonad than "S" ones and presented a complete spawning at the end of August contrary to the "S" which spawns partially. Mortality started in July when the seawater temperature reached 19 degree...
Tipo: Text
Palavras-chave: Summer; Reproduction; Oyster culture; Mortality; Genetic diversity; Commercial species; Breeding.
Ano: 2003
URL: http://archimer.ifremer.fr/doc/2003/acte-3345.pdf

In vitro modulation of reactive oxygen and nitrogen intermediate (ROI/RNI) production in Crassostrea gigas hemocytes
Provedor de dados: 5
Autores: Lambert, Christophe; Soudant, Philippe; Jegaden, Marine; Delaporte, Maryse; Labreuche, Yannick; Moal, Jeanne; Samain, Jean-francois.
Bivalve hemocyte competence has been measured by quantifying functional characteristics, including reactive oxygen intermediate (ROI) production after activation with zymosan or phorbol myristate acetate (PMA). However, untreated oyster hemocytes also produce ROI and RNI (reactive nitrogen intermediates) after bleeding even if not stimulated by Zymosan or PMA. Extensive investigation of this parameter by flow cytometry showed that, in vitro, ROI/RNI production by untreated hemocytes maintained in seawater appeared to be independent of both bacterial burden in the serum and non-self particle phagocytosis. ROI/ RNI production in granulocytes was higher than in hyalinocytes and could be intensified when activated by zymosan but not by PMA. Both cell types...
Tipo: Text
Palavras-chave: NO synthase; NADPH oxidase; Flow cytometry; Reactive nitrogen intermediate RNI; Reactive oxygen intermediate ROI; Hemocytes; Crassostrea gigas.
Ano: 2007
URL: http://archimer.ifremer.fr/doc/2007/publication-3057.pdf

Microplastics in seafood: Benchmark protocol for their extraction and characterization
Provedor de dados: 5
Autores: Dehaut, Alexandre; Cassone, Anne-laure; Frere, Laura; Hermabessiere, Ludovic; Himber, Charlotte; Rinnert, Emmanuel; Riviere, Gilles; Lambert, Christophe; Soudant, Philippe; Huvet, Arnaud; Duflos, Guillaume; Paul-pont, Ika.
Pollution of the oceans by microplastics (&lt;5 mm) represents a major environmental problem. To date, a limited number of studies have investigated the level of contamination of marine organisms collected in situ. For extraction and characterization of microplastics in biological samples, the crucial step is the identification of solvent(s) or chemical(s) that efficiently dissolve organic matter without degrading plastic polymers for their identification in a time and cost effective way. Most published papers, as well as OSPAR recommendations for the development of a common monitoring protocol for plastic particles in fish and shellfish at the European level, use protocols containing nitric acid to digest the biological tissues, despite reports of...
Tipo: Text
Palavras-chave: Microplastics; Digestion; Method; Seafood products; Tissue; Plastic integrity.
Ano: 2016
URL: https://archimer.ifremer.fr/doc/00335/44582/44469.pdf

Functional capacities of gill mitochondria in oyster Crassostrea gigas during an emersion/immersion tidal cycle
Provedor de dados: 5
Autores: Dudognon, Tony; Soudant, Philippe; Seguineau, Catherine; Quere, Claudie; Auffret, Michel; Kraffe, Edouard.
Sessile animals that live on the foreshore undergo tidal cycles, and have to face variations in physical and chemical parameters such as oxygen concentration. During emersion, availability of dissolved oxygen can be lowered for bivalves, which have only a small reserve of seawater inside their closed shell. Differences in oxygen concentration are thus expected to lead to modifications of the metabolism, including changes in mitochondrial activity. Previous studies investigated air exposure under extreme conditions, which do not always reflect environmental conditions these invertebrates have to cope with. In this study, oxidative capacities of gill mitochondria of the oyster Crassostrea gigas were studied during a tidal cycle period, by comparing oysters...
Tipo: Text
Palavras-chave: Mitochondria; Oxygen consumption; ATP production; Respiratory chain inhibitor; Crassostrea gigas.
Ano: 2013
URL: http://archimer.ifremer.fr/doc/00157/26854/24981.pdf

Molecular Characterization of Voltage-Gated Sodium Channels and Their Relations with Paralytic Shellfish Toxin Bioaccumulation in the Pacific Oyster Crassostrea gigas
Provedor de dados: 5
Autores: Boullot, Floriane; Castrec, Justine; Bidault, Adeline; Dantas, Natanael; Payton, Laura; Perrigault, Mickael; Tran, Damien; Amzil, Zouher; Boudry, Pierre; Soudant, Philippe; Hegaret, Helene; Fabioux, Caroline.
Paralytic shellfish toxins (PST) bind to voltage-gated sodium channels (Nav) and block conduction of action potential in excitable cells. This study aimed to (i) characterize Nav sequences in Crassostrea gigas and (ii) investigate a putative relation between Nav and PST-bioaccumulation in oysters. The phylogenetic analysis highlighted two types of Nav in C. gigas: a Nav1 (CgNav1) and a Nav2 (CgNav2) with sequence properties of sodium-selective and sodium/calcium-selective channels, respectively. Three alternative splice transcripts of CgNav1 named A, B and C, were characterized. The expression of CgNav1, analyzed by in situ hybridization, is specific to nervous cells and to structures corresponding to neuromuscular junctions. Real-time PCR analyses showed...
Tipo: Text
Palavras-chave: Crassostrea gigas; Sodium channel; Alternative splicing; Alexandrium minutum; Paralytic shellfish toxins.
Ano: 2017
URL: https://archimer.ifremer.fr/doc/00368/47877/47892.pdf

Physiological responses of Manila clams Venerupis (=Ruditapes) philippinarum with varying parasite Perkinsus olseni burden to toxic algal Alexandrium ostenfeldii exposure
Provedor de dados: 5
Autores: Lassudrie, Malwenn; Soudant, Philippe; Richard, Gaelle; Henry, N.; Medhioub, Walid; Da Silva, P.m.; Donval, Anne; Bunel, M.; Le Goïc, Nelly; Lambert, Christophe; De Montaudoin, X.; Fabioux, Caroline; Hegaret, Helene.
Manila clam stock from Arcachon Bay, France, is declining, as is commercial harvest. To understand the role of environmental biotic interactions in this decrease, effects of a toxic dinoflagellate, Alexandrium ostenfeldii, which blooms regularly in Arcachon bay, and the interaction with perkinsosis on clam physiology were investigated. Manila clams from Arcachon Bay, with variable natural levels of perkinsosis, were exposed for seven days to a mix of the nutritious microalga T-Iso and the toxic dinoflagellate A. ostenfeldii, a producer of spirolides, followed by seven days of depuration fed only T-Iso. Following sacrifice and quantification of protozoan parasite Perkinsus olseni burden, clams were divided into two groups according to intensity of the...
Tipo: Text
Palavras-chave: Bivalve; Harmful algal bloom; Oxidative stress; Venerupis philippinarum; Alexandrium ostenfeldii; Perkinsus olseni.
Ano: 2014
URL: http://archimer.ifremer.fr/doc/00189/30022/28507.pdf

Genetically based resistance to summer mortality in the Pacific oyster (Crassostrea gigas) and its relationship with physiological, immunological characteristics and infection processes
Provedor de dados: 5
Autores: Samain, Jean-francois; Degremont, Lionel; Soletchnik, Patrick; Haure, Joel; Bedier, Edouard; Ropert, Michel; Moal, Jeanne; Huvet, Arnaud; Bacca, Helene; Van Wormhoudt, A; Delaporte, Maryse; Costil, K; Pouvreau, Stephane; Lambert, Christian; Boulo, Viviane; Soudant, Philippe; Nicolas, Jean-louis; Leroux, Frederique; Renault, Tristan; Gagnaire, Beatrice; Geret, Florence; Boutet, Isabelle; Burgeot, Thierry; Boudry, Pierre.
Summer mortality of Pacific oysters is known in several countries. However no specific pathogen has been systematically associated with this phenomenon. A complex combination of environmental and biological parameters has been suggested as the cause and is now starting to be identified. A high genetic basis was found for survival in oysters when a first generation (G1) was tested in three sites during summer. This paper presents a synthesis on physiological characteristics of two selected groups ('R' and 'S', from families selected for resistance and susceptibility to summer mortality respectively), of the second and third generations. R and S showed improvement or reduction of survival compared with the control in both field and laboratory trials...
Tipo: Text
Palavras-chave: ROS; Temperature; Stress; Hemocytes; Reproduction; Genetic selection; Resistant oyster; Crassostrea gigas; Pacific Oyster; Summer mortality.
Ano: 2007
URL: http://archimer.ifremer.fr/doc/2007/publication-2809.pdf

Influence of Crassostrea gigas (Thunberg) sexual maturation stage and ploidy on uptake of paralytic phycotoxins
Provedor de dados: 5
Autores: Gueguen, Marielle; Baron, Regis; Bardouil, Michele; Haberkorn, Hansy; Soudant, Philippe; Truquet, Philippe; Lassus, Patrick.
The purpose of this study was to assess paralytic phycotoxin uptake in diploid and triploid oysters at two stages of their sexual cycle corresponding to their status in early summer (June) and winter (November). Samples of diploid and triploid oysters were exposed to a toxic culture of Alexandrium minutum for 4 days in each season. No significant differences in filtration or clearance rates were observed during either November or June experiments. When diploid oysters were at resting stage (November), toxin uptake showed no significant difference between the ploidy classes. In contrast, when the diploid oysters were at the peak of their sexual maturation (June), the triploid oysters were seen to accumulate almost double the amount of paralytic toxins as...
Tipo: Text
Palavras-chave: Paralytic shellfish poisoning; Crassostrea gigas; Diploid; Triploid; Contamination.
Ano: 2012
URL: http://archimer.ifremer.fr/doc/00087/19796/17487.pdf

Evaluation of toxicity of Deepwater Horizon slick oil on spat of the oyster Crassostrea virginica
Provedor de dados: 5
Autores: Vignier, Julien; Rolton, Anne; Soudant, Philippe; Chu, Fu-lin E.; Robert, Rene; Volety, Aswani K.
The 2010 explosion of the Deepwater Horizon (DWH) oil rig generated the largest marine oil spill in US history with millions of barrels of crude oil released in the Gulf of Mexico (GoM). The eastern oyster, Crassostrea virginica, is an ecologically and economically important species in the northern GoM. Due to its biological characteristics (sessile, filter feeding), juvenile oysters may have been affected. This study investigated the effects of surface-collected DWH oil prepared as high-energy water-accommodated fraction (HEWAF) on the survival of 2-month-old oyster spat, and evaluated the potential impacts of HEWAF on particle clearance rate and spat tissue. Exposure of oysters to a range of oil/HEWAF (0-7-66-147-908-3450 mu g tPAH50 (sum of 50...
Tipo: Text
Palavras-chave: Oyster spat; Deepwater Horizon oil; Sublethal; Tissue; Inflammatory response; Histopathology.
Ano: 2018
URL: https://archimer.ifremer.fr/doc/00425/53615/54548.pdf

Reproductive strategy of the invasive green mussel may result in increased competition with native fauna in the southeastern United States
Provedor de dados: 5
Autores: Mcfarland, Katherine; Soudant, Philippe; Jean, Frederic; Volety, Aswani K.
Understanding the population dynamics of invasive species, such as the green mussel Perna viridis (Linnaeus, 1758), can aid in explaining the success of newly introduced populations and help predict the potential for spread. During a two-year field study of established populations in the invaded region of southwest Florida, year round gametogenesis and continuous spawning capabilities were observed through histological analysis of mussels collected monthly. This was supported by overall stable energetic reserves as measured through proximal biochemical composition (protein, glycogen and lipid content). However, egg outputs in the summer (6.4 x 10(6) +/- 2.6 x 10(6) eggs / female) were significantly higher than egg outputs of winter-spawned mussels (7.7 x...
Tipo: Text
Palavras-chave: Gametogenesis; Protein; Glycogen; Lipid; Induced spawning.
Ano: 2016
URL: https://archimer.ifremer.fr/doc/00616/72842/72974.pdf

Interactions between microplastics and phytoplankton aggregates : Impact on their respective fates
Provedor de dados: 5
Autores: Long, Marc; Moriceau, Brivaela; Gallinari, Morgane; Lambert, Christophe; Huvet, Arnaud; Raffray, Jean; Soudant, Philippe.
Plastic debris are resistant to degradation, and therefore tend to accumulate in marine environment. Nevertheless recent estimations of plastic concentrations at the surface of the ocean were lower than expected leading the communities to seek new sinks. Among the different processes suggested we chose to focus on the transport of microplastics from the surface to deeper layers of the ocean via phytoplankton aggregates that constitute most of the sinking flux. Interactions between microplastics and aggregates were studied by building a new device: the flow-through roller tank that mimics the behaviour of laboratory made aggregates sinking through a dense layer of microplastics. Three types of aggregates formed from two different algae species (the diatom...
Tipo: Text
Palavras-chave: Microplastic sink; Vertical export; Diatom and cryptophyte aggregates; Settling rate; Permeability.
Ano: 2015
URL: https://archimer.ifremer.fr/doc/00259/37048/35557.pdf

Perkinsosis in Europe : current issues and research needs
Provedor de dados: 5
Autores: Berthe, Franck; Choi, K. S.; Figueras, Antonio; Soudant, Philippe; Villalba, A.
The aim of this workshop was to review current issues posed by perkinsosis in Europe with particular emphasis on taxonomv. epidemiology and impact an mollusc stocks, and identify where new developments in research are likely to improve our knowledge and understandings.
Tipo: Text
Palavras-chave: Parasitic diseases; Pathogens; Geographical distribution; Fish diseases; Perkinsus marinus; Pathology.
Ano: 2004
URL: https://archimer.ifremer.fr/doc/2004/publication-3290.pdf

Polystyrene microbeads modulate the energy metabolism of the marine diatom Chaetoceros neogracile
Provedor de dados: 5
Autores: Seoane, Marta; González-fernández, Carmen; Soudant, Philippe; Huvet, Arnaud; Esperanza, Marta; Cid, Ángeles; Paul-pont, Ika.
Due to the growing concern about the presence of microplastics (MP) in the environment, the number of studies evaluating the toxicity of these small persistent particles on different marine species has increased in recent years. Few studies have addressed their impact on marine phytoplankton, a subject of great concern since they are primary producers of the aquatic food web. The aim of this study is to unravel the cytotoxicity of 2.5 μg mL−1 unlabelled amino-modified polystyrene beads of different sizes (0.5 and 2 μm) on the marine diatom Chaetoceros neogracile. In addition to traditional growth and photosynthesis endpoints, several physiological and biochemical parameters were monitored every 24 h in C. neogracile cells by flow cytometry during their...
Tipo: Text
Palavras-chave: Microalgae; Microplastic; Flow cytometry; Cytotoxicity; Scanning electron microscopy.
Ano: 2019
URL: https://archimer.ifremer.fr/doc/00492/60415/63850.pdf

Relationship between valve activity, microalgae concentration in the water and toxin accumulation in the digestive gland of the Pacific oyster Crassostrea gigas exposed to Alexandrium minutum
Provedor de dados: 5
Autores: Haberkorn, Hansy; Tran, Damien; Massabuau, Jean-charles; Ciret, Pierre; Savar, Veronique; Soudant, Philippe.
The complexity of the relationships between Alexandrium minutum (Am.) concentration in the water ([A.m.](w)), Paralytic Shellfish Poisoning contamination in the digestive gland ([PSP](dg)) and valve behavior was explored in oysters Crassostrea gigas. Two experiments were conducted, during which oysters' valve behaviour were analyzed. Oysters, first acclimated for 10-days with the non harmful microalgae Heterocapsa triquetra (H.t.), were exposed to four microalgae mixtures at constant total concentrations of 10 x 10(3) cells ml(-1) (experiment-1) and 5 x 10(3) cells ml(-1) (experiment-2): 100% Am.; 50% A.m.-50% H.t.; 25% A.m.-75% H.t.; 100% H.t. At the end of experiment-2, [PSP](dg) were measured. At 10 x 103 cells ml(-1), the microalgal ingestion decreased...
Tipo: Text
Palavras-chave: Harmful algae; Oysters; Behavioral responses; Algae concentration; Toxin accumulation.
Ano: 2011
URL: http://archimer.ifremer.fr/doc/00041/15195/12617.pdf

ATP content and viability of spermatozoa drive variability of fertilization success in the Pacific oyster ( Crassostrea gigas )
Provedor de dados: 5
Autores: Boulais, Myrina; Soudant, Philippe; Le Goic, Nelly; Quere, Claudie; Boudry, Pierre; Suquet, Marc.
Fertilization of the oocyte is a critical process of sexual reproduction depending among other factors on spermatozoa functionality. Mitochondria participate in many crucial processes for spermatozoa motility and fertilizing ability. The Pacific oyster, Crassostrea gigas, is characterized by a high inter-individual variability of its reproductive success which has been shown to be partially due to the variability of gamete quality. The present study explored spermatozoa characteristics such as: i) relationships among mitochondrial functionality (ATP content, mitochondrial membrane potential (MMP), reactive oxygen species production); sperm viability (percentages of live, dying, and dead); and motility; and ii) their involvement in inter-oyster variability...
Tipo: Text
Palavras-chave: Spermatozoa; Quality; Motility; Viability; ATP content; ROS production.
Ano: 2017
URL: http://archimer.ifremer.fr/doc/00386/49769/50309.pdf

Cellular responses of Pacific oyster ( Crassostrea gigas ) gametes exposed in vitro to polystyrene nanoparticles
Provedor de dados: 5
Autores: Gonzalez-fernandez, Carmen; Tallec, Kevin; Le Goic, Nelly; Lambert, Christophe; Soudant, Philippe; Huvet, Arnaud; Suquet, Marc; Berchel, Mathieu; Paul-pont, Ika.
While the detection and quantification of nano-sized plastic in the environment remains a challenge, the growing number of polymer applications mean that we can expect an increase in the release of nanoplastics into the environment by indirect outputs. Today, very little is known about the impact of nano-sized plastics on marine organisms. Thus, the objective of this study was to investigate the toxicity of polystyrene nanoplastics (NPs) on oyster (Crassostrea gigas) gametes. Spermatozoa and oocytes were exposed to four NPs concentrations ranging from 0.1 to 100 mg L−1 for 1, 3 and 5 h. NPs coated with carboxylic (PS-COOH) and amine groups (PS-NH2) were used to determine how surface properties influence the effects of nanoplastics. Results demonstrated the...
Tipo: Text
Palavras-chave: Nanoplastics; Oysters; Gametes; Cellular responses.
Ano: 2018
URL: https://archimer.ifremer.fr/doc/00443/55459/56976.pdf

Cellular and molecular hemocyte responses of the Pacific oyster, Crassostrea gigas, following bacterial infection with Vibrio aestuarianus strain 01/32
Provedor de dados: 5
Autores: Labreuche, Yannick; Lambert, Christophe; Soudant, Philippe; Boulo, Viviane; Huvet, Arnaud; Nicolas, Jean-louis.
The strategies used by bacterial pathogens to circumvent host defense mechanisms remain largely undefined in bivalve molluscs. In this study, we investigated experimentally the interactions between the Pacific oyster (Crassostrea gigas) immune system and Vibrio aestuarianus strain 01/32, a pathogenic bacterium originally isolated from moribund oysters. First, an antibiotic-resistant V. aestuarianus strain was used to demonstrate that only a limited number of bacterial cells was detected in the host circulatory system, suggesting that the bacteria may localize in some organs. Second, we examined the host defense responses to V. aestuarianus at the cellular and molecular levels, using flow-cytometry and real-time PCR techniques. We showed that hemocyte...
Tipo: Text
Palavras-chave: Crassostrea gigas; Oyster; Pathogenesis; Vibrio aestuarianus; Bivalve immunity.
Ano: 2006
URL: http://archimer.ifremer.fr/doc/2006/publication-2182.pdf

Vibrio aestuarianus zinc metalloprotease causes lethality in the Pacific oyster Crassostrea gigas and impairs the host cellular immune defenses
Provedor de dados: 5
Autores: Labreuche, Yannick; Le Roux, Frederique; Henry, Joel; Zatylny, Celine; Huvet, Arnaud; Lambert, Christophe; Soudant, Philippe; Mazel, Didier; Nicolas, Jean-louis.
Extracellular products (ECPs) of the pathogenic Vibrio aestuarianus 01/32 were previously reported to display lethality in Crassostrea gigas oysters and to cause morphological changes and immunosuppression in oyster hemocytes. To identify the source of this toxicity, biochemical and genetic approaches were developed. ECP protease activity and lethality were shown to be significantly reduced following incubation with metal chelators, suggesting the involvement of a zinc metalloprotease. An open reading frame of 1836 bp encoding a 611-aa metalloprotease (designated yam) was identified. The deduced protein sequence showed high homology to other Vibrio metalloproteases reported to be involved in pathogenicity. To further confirm the role of this enzyme in ECP...
Tipo: Text
Palavras-chave: Vibrio aestuarianus; Metalloprotease; Crassostrea gigas; Oyster; Hemocytes; Extracellular products.
Ano: 2010
URL: http://archimer.ifremer.fr/doc/00015/12649/9588.pdf

Asari clam (Ruditapes philippinarum) in France: history of an exotic species 1972 – 2015
Provedor de dados: 5
Autores: De Montaudouin, Xavier; Arzul, Isabelle; Caill-milly, Nathalie; Khayati, Alice; Labrousse, Jean-michel; Lafitte, Céline; Paillard, Christine; Soudant, Philippe; Goulletquer, Philippe.
In 1972, France underwent an oyster (Crassostrea angulata) crisis and urgently needed to diversify its aquaculture. Thus, Asari clam (Ruditapes philippinarum) was introduced at that time for aquaculture purpose, concomitantly with the introduction of Pacific oyster (Crassostrea gigas). All Asari clam adults and spat originated from the same area (Puget Sound, WA, USA). After a promising start and the implementation of a national Research &amp; Development program, Asari clam culture rapidly faced a series of concomitant handicaps: firstly, in spite the fact that cultural practices were optimized and locking points addressed, leasing ground availability was limited during the 1980s’ due to certain reluctance from oyster farmers to share their leases and/or...
Tipo: Text
Palavras-chave: Ruditapes philippinarum; France; Aquaculture; Professional fishing; Diseases; Environmental stressors.
Ano: 2016
URL: http://archimer.ifremer.fr/doc/00366/47767/47817.pdf

The dinoflagellate Alexandrium minutum affects development of the oyster Crassostrea gigas, through parental or direct exposure
Provedor de dados: 5
Autores: Castrec, Justine; Hegaret, Helene; Alunno-bruscia, Marianne; Picard, Mailys; Soudant, Philippe; Petton, Bruno; Boulais, Myrina; Suquet, Marc; Queau, Isabelle; Ratiskol, Dominique; Foulon, Valentin; Le Goic, Nelly; Fabioux, Caroline.
Harmful algal blooms are a threat to aquatic organisms and coastal ecosystems. Among harmful species, the widespread distributed genus Alexandrium is of global importance. This genus is well-known for the synthesis of paralytic shellfish toxins which are toxic for humans through the consumption of contaminated shellfish. While the effects of Alexandrium species upon the physiology of bivalves are now well documented, consequences on reproduction remain poorly studied. In France, Alexandrium minutum blooms have been recurrent for the last decades, generally appearing during the reproduction season of most bivalves including the oyster Crassostrea gigas. These blooms could not only affect gametogenesis but also spawning, larval development or juvenile...
Tipo: Text
Palavras-chave: Harmful algal bloom (HAB); Paralytic shellfish toxin (PST); Crassostrea gigas; Gametes; Larvae.
Ano: 2019
URL: https://archimer.ifremer.fr/doc/00469/58099/60512.pdf

Impact of the toxic dinoflagellate Alexandrium catenella on Pacific oyster reproductive output: application of flow cytometry assays on spermatozoa
Provedor de dados: 5
Autores: Le Goic, Nelly; Hegaret, Helene; Fabioux, Caroline; Miner, Philippe; Suquet, Marc; Lambert, Christophe; Soudant, Philippe.
The toxic dinoflagellate Alexandrium catenella recurrently blooms on the coasts of France and produces Paralytic Shellfish Toxins (PSTs) that accumulate in bivalves. These toxins can affect various physiological functions including reproduction. The present study aims to validate measurements of sperm viability, DNA content and mitochondrial membrane potential in Pacific oyster Crassostrea gigas using flow cytometry coupled with fluorescent markers, and to use these measurements to assess the cellular parameters of sperm from Pacific oysters exposed to A. catenella. These parameters may influence fertilization, embryogenesis and larval development in free-spawning shellfish. Sperm viability and DNA content estimation were assessed using SYBR-14, which only...
Tipo: Text
Palavras-chave: Harmful algal bloom; Sperm quality; Cellular parameters; Flow cytometry; Pacific oyster; Crassostrea gigas; Alexandrium catenella.
Ano: 2013
URL: http://archimer.ifremer.fr/doc/00157/26853/24982.pdf

Constraints and Priorities for Conducting Experimental Exposures of Marine Organisms to Microplastics
Provedor de dados: 5
Autores: Paul-pont, Ika; Tallec, Kevin; Gonzalez-fernandez, Carmen; Lambert, Christophe; Vincent, Dorothee; Mazurais, David; Zambonino-infante, Jose-luis; Brotons, Guillaume; Lagarde, Fabienne; Fabioux, Caroline; Soudant, Philippe; Huvet, Arnaud.
Marine plastic pollution is a major environmental issue. Given their ubiquitous nature and small dimensions, ingestion of microplastic (MP) and nanoplastic (NP) particles and their subsequent impact on marine life are a growing concern worldwide. Transfers along the trophic chain, including possible translocation, for which the hazards are less understood, are also a major preoccupation. Effects of MP ingestion have been studied on animals through laboratory exposure, showing impacts on feeding activity, reserve depletion and inflammatory responses, with consequences for fitness, notably reproduction. However, most experimental studies have used doses of manufactured virgin microspheres that may not be environmentally realistic. As for most...
Tipo: Text
Palavras-chave: Microplastics; Nanoplastics; Experimental exposure; Impacts; Marine organisms; Physiology.
Ano: 2018
URL: https://archimer.ifremer.fr/doc/00449/56088/57621.pdf

Effects of Alexandrium minutum exposure on nutrition-related processes and reproductive output in oysters Crassostrea gigas
Provedor de dados: 5
Autores: Haberkorn, Hansy; Lambert, Christophe; Le Goic, Nelly; Moal, Jeanne; Suquet, Marc; Gueguen, Marielle; Sunila, Inke; Soudant, Philippe.
This study assessed the effects of an artificial bloom of the toxin-producing dinoflagellate, Alexandrium minutum, upon nutrition related processes and reproductive output of the Pacific oyster, Crassostrea gigas. Oysters were exposed to A. minutum, Paralytic Shellfish Toxins (PST) producer and compared to a control batch of oysters fed Isochrysis galbana clone Tahitian (T.Iso). The experiment was performed in June 2008, when oysters were found ripe. Several physiological variables of oysters, such as PSTs accumulation, digestive gland and histological observations as well as spermatozoa quality, were measured at the end of the exposure. Results indicate that the digestive gland was greatly impacted upon A. minutum exposure. Monoacylglycerol and...
Tipo: Text
Palavras-chave: Harmful algae; Alexandrium minutum; Oyster; Nutrition-related processes; Reproductive output.
Ano: 2010
URL: http://archimer.ifremer.fr/doc/00008/11927/8653.pdf

Alexandrium ostenfeldii growth and spirolide production in batch culture and photobioreactor
Provedor de dados: 5
Autores: Medhioub, Walid; Sechet, Veronique; Truquet, Philippe; Bardouil, Michele; Amzil, Zouher; Lassus, Patrick; Soudant, Philippe.
Growth and spirolide production of the toxic dinoflagellate Alexandrium ostenfeldii (Danish strain CCMP1773) were studied in batch culture and a photobioreactor (continuous cultures). First, batch cultures were grown in 450 mL flasks without aeration and under varying conditions of temperature (16 and 22 degrees C) and culture medium (L1, f/2 and L1 with addition of soil extract). Second, cultures were grown at 16 degrees C in 8 L aerated flat-bottomed vessels using L1 with soil extract as culture medium. Finally, continuous cultures in a photobioreactor were conducted at 18 degrees C in L1 with soil extract; pH was maintained at 8.5 and continuous stirring was applied. This study showed that A. ostenfeldii growth was significantly affected by temperature....
Tipo: Text
Palavras-chave: Alexandrium ostenfeldii; Batch; Growth; Photobioreactor; Spirolide production.
Ano: 2011
URL: http://archimer.ifremer.fr/doc/00049/16050/15784.pdf

Flow cytometric assessment of morphology, viability, and production of reactive oxygen species of Crassostrea gigas oocytes. Application to Toxic dinoflagellate (Alexandrium minutum) exposure
Provedor de dados: 5
Autores: Le Goic, Nelly; Hegaret, Helene; Boulais, Myrina; Beguel, Jean-philippe; Lambert, Christophe; Fabioux, Caroline; Soudant, Philippe.
The Pacific oyster Crassostrea gigas accounts for a large part of shellfish aquaculture production worldwide. Aspects of morphological and functional characteristics of oyster oocytes remain poorly documented, and traditional techniques, such as microscopic observations of shape or fertilization rate, are time and space consuming. The purpose of this study was to assess for the first time viability and reactive oxygen species (ROS) production of Pacific oyster oocytes using flow cytometry (FCM) and to apply this method to determine oocyte responses to in vitro exposure to the toxic dinoflagellate Alexandrium minutum. A culture of A. minutum caused a significant increase in oocyte ROS production, which gradually increased with the age of the culture, but...
Tipo: Text
Palavras-chave: Pacific oyster; Gamete quality; ROS production; Viability; Flow cytometry; Ecotoxicology.
Ano: 2014
URL: https://archimer.ifremer.fr/doc/00216/32760/31321.pdf

Exposure to toxic Alexandrium minutum activates the detoxifying and antioxidant systems in gills of the oyster Crassostrea gigas
Provedor de dados: 5
Autores: Fabioux, Caroline; Sulistiyani, Yeni; Haberkorn, Hansy; Hegaret, Helene; Amzil, Zouher; Soudant, Philippe.
Harmful algal blooms of Alexandrium spp. dinoflagellates regularly occur in French coastal waters contaminating shellfish. Studies have demonstrated that toxic Alexandrium spp. disrupt behavioural and physiological processes in marine filter-feeders, but molecular modifications triggered by phycotoxins are less well understood. This study analyzed the mRNA levels of 7 genes encoding antioxidant/detoxifying enzymes in gills of Pacific oysters (Crassostrea gigas) exposed to a cultured, toxic strain of A. minutum, a producer of paralytic shellfish toxins (PST) or fed Tisochrysis lutea (T. lutea, formerly Isochrysis sp., clone Tahitian (T. iso)), a non-toxic control diet, in four repeated experiments. Transcript levels of sigma-class glutathione S-transferase...
Tipo: Text
Palavras-chave: Crassostrea gigas; Alexandrium minutum; Paralytic shellfish toxins; Antioxidant enzymes; Detoxification enzymes; MRNA.
Ano: 2015
URL: https://archimer.ifremer.fr/doc/00275/38601/38623.pdf

Reply to Lenz et al.: Quantifying the smallest microplastics is the challenge for a comprehensive view of their environmental impacts
Provedor de dados: 5
Autores: Huvet, Arnaud; Paul-pont, Ika; Fabioux, Caroline; Lambert, Christophe; Suquet, Marc; Thomas, Yoann; Robbens, Johan; Soudant, Philippe; Sussarellu, Rossana.
Tipo: Text
Ano: 2016
URL: https://archimer.ifremer.fr/doc/00345/45604/45224.pdf

Occurrence and effects of plastic additives on marine environments and organisms: A review
Provedor de dados: 5
Autores: Hermabessiere, Ludovic; Dehaut, Alexandre; Paul-pont, Ika; Lacroix, Camille; Jezequel, Ronan; Soudant, Philippe; Duflos, Guillaume.
Plastics debris, especially microplastics, have been found worldwide in all marine compartments. Much research has been carried out on adsorbed pollutants on plastic pieces and hydrophobic organic compounds (HOC) associated with microplastics. However, only a few studies have focused on plastic additives. These chemicals are incorporated into plastics from which they can leach out as most of them are not chemically bound. As a consequence of plastic accumulation and fragmentation in oceans, plastic additives could represent an increasing ecotoxicological risk for marine organisms. The present work reviewed the main class of plastic additives identified in the literature, their occurrence in the marine environment, as well as their effects on and transfers...
Tipo: Text
Palavras-chave: Microplastics; Plastic additives; Bisphenol A; Phthalates; Brominated flame retardant.
Ano: 2017
URL: http://archimer.ifremer.fr/doc/00391/50227/51394.pdf

Nanoplastics exposure modulate lipid and pigment compositions in diatoms
Provedor de dados: 5
Autores: Gonzalez-fernandez, Carmen; Le Grand, Fabienne; Bideau, Antoine; Huvet, Arnaud; Paul-pont, Ika; Soudant, Philippe.
The impact of nanoplastics (NP) using model polystyrene nanoparticles amine functionalized (PS–NH2) has been investigated on pigment and lipid compositions of the marine diatom Chaetoceros neogracile, at two growth phases using a low (0.05 μg mL−1) and a high (5 μg mL−1) concentrations for 96 h. Results evidenced an impact on pigment composition associated to the light-harvesting function and photoprotection mainly at exponential phase. NP also impacted lipid composition of diatoms with a re-adjustment of lipid classes and fatty acids noteworthy. Main changes upon NP exposure were observed in galactolipids and triacylglycerol's at both growth phases affecting the thylakoids membrane structure and cellular energy reserve of diatoms. Particularly,...
Tipo: Text
Palavras-chave: Diatoms; Nanoplastics; Lipid composition; Pigments.
Ano: 2020
URL: https://archimer.ifremer.fr/doc/00611/72283/71083.pdf

Oyster reproduction is affected by exposure to polystyrene microplastics
Provedor de dados: 5
Autores: Sussarellu, Rossana; Suquet, Marc; Thomas, Yoann; Lambert, Christophe; Fabioux, Caroline; Pernet, Marie Eve Julie; Le Goic, Nelly; Quillien, Virgile; Mingant, Christian; Epelboin, Yanouk; Corporeau, Charlotte; Guyomarch, Julien; Robbens, Johan; Paul-pont, Ika; Soudant, Philippe; Huvet, Arnaud.
Plastics are persistent synthetic polymers that accumulate as waste in the marine environment. Microplastic (MP) particles are derived from the breakdown of larger debris or can enter the environment as microscopic fragments. Because filter-feeder organisms ingest MP while feeding, they are likely to be impacted by MP pollution. To assess the impact of polystyrene microspheres (micro-PS) on the physiology of the Pacific oyster, adult oysters were experimentally exposed to virgin micro-PS (2 and 6 µm in diameter; 0.023 mg·L−1) for 2 mo during a reproductive cycle. Effects were investigated on ecophysiological parameters; cellular, transcriptomic, and proteomic responses; fecundity; and offspring development. Oysters preferentially ingested the 6-µm micro-PS...
Tipo: Text
Palavras-chave: Microplastic; Reproduction; Energy allocation; Oyster.
Ano: 2016
URL: https://archimer.ifremer.fr/doc/00311/42233/41600.pdf

Modelling paralytic shellfish toxins (PST) accumulation in Crassostrea gigas by using Dynamic Energy Budgets (DEB)
Provedor de dados: 5
Autores: Pousse, Emilien; Flye-sainte-marie, Jonathan; Alunno-bruscia, Marianne; Hegaret, Helene; Rannou, Eric; Pecquerie, Laure; Marques, Goncalo M.; Thomas, Yoann; Castrec, Justine; Fabioux, Caroline; Long, Marc; Lassudrie, Malwenn; Hermabessiere, Ludovic; Amzil, Zouher; Soudant, Philippe; Jean, Fred.
As other filter-feeders, Crassostrea gigas can concentrate paralytic shellfish toxins (PST) by consuming dinoflagellate phytoplankton species like Alexandrium minutum. Intake of PST in oyster tissues mainly results from feeding processes, i.e. clearance rate, pre-ingestive sorting and ingestion that are directly influenced by environmental conditions (trophic sources, temperature). This study aimed to develop a mechanistic model coupling the kinetics of PST accumulation and bioenergetics in C. gigas based on Dynamic Energy Budget (DEB) theory. For the first time, the Synthesizing Units (SU) concept was applied to formalize the feeding preference of oysters between non-toxic and toxic microalgae. Toxin intake and accumulation were both dependent on the...
Tipo: Text
Palavras-chave: Alexandrium minutum; Paralytic shellfish toxins (PST); Dynamic Energy Budget (DEB); Modelling; Pacific oyster.
Ano: 2019
URL: https://archimer.ifremer.fr/doc/00455/56662/58407.pdf

Interactions between Crassostrea virginica larvae and Deepwater Horizon oil: Toxic effects via dietary exposure
Provedor de dados: 5
Autores: Vignier, J.; Rolton, A.; Soudant, Philippe; Chu, F. L. E.; Robert, Rene; Volety, A. K.
The Deepwater Horizon (DWH) disaster released crude oil in the Gulf of Mexico for 87 days, overlapping with the reproductive season and recruitment of the oyster Crassostrea virginica. The pelagic larval life stages of C. virginica are particularly vulnerable to contaminants such as polycyclic aromatic hydrocarbons (PAHs) and oil droplets. Based on their lipophilic properties, PAHs and oil droplets can adsorb onto phytoplankton and filter-feeding C. virginica larvae may be exposed to these contaminants bound to suspended sediment, adsorbed onto algal and other particles, or in solution. This study examined the effects of exposure of C. virginica larvae to algae mixed with DWH oil. In a 14-day laboratory exposure, 5 day-old C. virginica larvae were exposed...
Tipo: Text
Palavras-chave: Deepwater Horizon oil; Droplet; Oyster larvae; Dietary exposure; PAH.
Ano: 2019
URL: https://archimer.ifremer.fr/doc/00473/58423/61445.pdf

The combined effects of blue light and dilution rate on lipid class and fatty acid composition of Tisochrysis lutea
Provedor de dados: 5
Autores: Marchetti, Julie; Da Costa, Fiz; Bougaran, Gael; Quere, Claudie; Soudant, Philippe; Robert, Rene.
The lipid class and the fatty acid compositions of microalgae highly influence bivalve larval and post-larval development. Light is an essential environmental factor for microalgal culture, and quantity and quality of light may induce changes in the biochemical composition of the algae. The objective of this study was to investigate the effect of light spectrum (blue vs. white light) on lipid class and fatty acid compositions of Tisochrysis lutea cultured in a chemostat. Two different dilution rates (D) were assayed for each light spectrum: 0.2 and 0.7 day−1. Triacylglycerol (TAG), sterol, and hydrocarbon (HC) content increased sharply at low D. The proportion of alkenones was significantly reduced under blue light. Polyunsaturated fatty acids (PUFA), and...
Tipo: Text
Palavras-chave: Tisochrysis lutea; Blue light; Dilution rate; Lipid classes; Fatty acids; Chemostat.
Ano: 2018
URL: https://archimer.ifremer.fr/doc/00412/52299/53355.pdf

Allelochemicals from Alexandrium minutum induce rapid inhibition of metabolism and modify the membranes from Chaetoceros muelleri
Provedor de dados: 5
Autores: Long, Marc; Tallec, Kevin; Soudant, Philippe; Le Grand, Fabienne; Donval, Anne; Lambert, Christophe; Sarthou, Geraldine; Jolley, Dianne F.; Hegaret, Helene.
Allelochemical interactions are likely to be a contributing factor explaining the success of large blooms of the harmful marine dinoflagellate Alexandrium, however, the physiological mechanisms of allelochemical interactions remain poorly described. Here we investigated the sub-lethal effects (on an hourly scale) of a filtrate containing allelochemicals from Alexandrium minutum on the physiology of the common diatom Chaetoceros muelleri. The filtrate induced deleterious effects to the diatom physiology within only 30 min of exposure. Esterase activity and photosynthesis were drastically inhibited, with up to 34% of the population being metabolically inactive and up to 30% reduction in photosystem II quantum yield when exposed to the filtrate. In addition,...
Tipo: Text
Palavras-chave: Allelopathy; Alexandrium; Metabolism; Photoinhibition; Lipids; Pigments.
Ano: 2018
URL: https://archimer.ifremer.fr/doc/00460/57133/59748.pdf

Effect of a mono-specific algal diet on immune functions in two bivalve species - Crassostrea gigas and Ruditapes philippinarum
Provedor de dados: 5
Autores: Delaporte, Maryse; Soudant, Philippe; Moal, Jeanne; Lambert, Christophe; Quere, Claudie; Miner, Philippe; Choquet, Gwenaelle; Paillard, Christine; Samain, Jean-francois.
The impact of diets upon the fatty acid composition of haemocyte polar lipids and consequently upon immune parameters has been tested in the oyster Crassostrea gigas and the clam Ruditapes philippinarum. Oysters and clams were fed each of three cultured algae: Chaetoceros calcitrans, which is rich in 20:5(n-3) and 20:4(n-6) and poor in 22:6(n-3) fatty acids; T-Iso (Isochrysis sp.), which is rich in 22:6(n-3) and deficient in 20:5(n-3) and 20:4(n-6); and Tetraselmis suecica, which is deficient in 22:6(n-3) and contains only small amounts of 20:5(n-3) and 20:4(n-6). Fatty acid composition of haemocyte polar lipids was greatly affected by the diet. Oysters and clams fed C. calcitrans maintained a higher proportion of 20:5(n-3) and 20:4(n-6) in their haemocyte...
Tipo: Text
Palavras-chave: Ruditapes philippinarum; Crassostrea gigas; Polyunsaturated fatty acids; Phagocytosis; Oxidative activity; Haemocyte membrane; Nutrition; Immunology; Bivalve; Immunologie; Bivalve; Ruditapes philippinarum; Crassostrea gigas; Acides gras poly insatures; Phagocytose; Flambee respiratoire; Membrane; Hemocyte; Nutrition.
Ano: 2003
URL: http://archimer.ifremer.fr/doc/2003/publication-354.pdf

Spirolide uptake and detoxification by Crassostrea gigas exposed to the toxic dinoflagellate Alexandrium ostenfeldii
Provedor de dados: 5
Autores: Medhioub, Walid; Lassus, Patrick; Truquet, Philippe; Bardouil, Michele; Amzil, Zouher; Sechet, Veronique; Sibat, Manoella; Soudant, Philippe.
Oysters (Crassostrea gigas) were exposed 4 days to cultures of the toxic dinoflagellate Alexandrium ostenfeldii (strain CCMP1773) that produces spirolides belonging to fast acting toxins (FAT) and let depurate for 7 days. During depuration, oysters were either fed the non-toxic algae Isochrysis galbana Tahitian clone (T. Iso) or starved. The objectives of this experiment were to evaluate (i) spirolide uptake and depuration by oysters (ii) spirolide effects on oysters and (iii) oyster recovery according to food supply during depuration. A. ostenfeldii cells were filtered and ingested by oysters while faeces contained numerous intact cells of the toxic diet. This suggested that ingested cells were not totally digested by oysters. Contents of spirolides (SPX)...
Tipo: Text
Palavras-chave: Spirolides; Alexandrium ostenfeldii; Contamination; Depuration; Crassostrea gigas; Inflammatory responses.
Ano: 2012
URL: http://archimer.ifremer.fr/doc/00098/20953/18740.pdf

Do transparent exopolymeric particles (TEP) affect the toxicity of nanoplastics on Chaetoceros neogracile?
Provedor de dados: 5
Autores: González-fernández, Carmen; Toullec, Jordan; Lambert, Christophe; Le Goïc, Nelly; Seoane, Marta; Moriceau, Brivaela; Huvet, Arnaud; Berchel, Mathieu; Vincent, Dorothée; Courcot, Lucie; Soudant, Philippe; Paul-pont, Ika.
The potential presence of nanoplastics (NP) in aquatic environments represents a growing concern regarding their possible effects on aquatic organisms. The objective of this study was to assess the impact of polystyrene (PS) amino-modified particles (50  nm PSNH2) on the cellular and metabolic responses of the diatom Chaetoceros neogracile cultures at two essential phases of the growth cycle, i.e. exponential (division) and stationary (storage) phases. Both cultures were exposed for 4 days to low (0.05 μg mL−1) and high (5 μg mL−1) concentrations of PS-NH2. Exposure to NP impaired more drastically the major cellular and physiological parameters during exponential phase than during the stationary phase. Only an increase in ROS production was observed at...
Tipo: Text
Palavras-chave: Nanoplastics; Diatoms; Physiology; Transparent exopolymer particles.
Ano: 2019
URL: https://archimer.ifremer.fr/doc/00491/60235/63627.pdf

Impact of 20 : 4n-6 supplementation on the fatty acid composition and hemocyte parameters of the Pacific oyster Crassostrea gigas
Provedor de dados: 5
Autores: Delaporte, Maryse; Soudant, Philippe; Moal, Jeanne; Giudicelli, Emilie; Lambert, Christophe; Seguineau, Catherine; Samain, Jean-francois.
Arachidonic acid (20:4n-6, ArA) and its eicosanoid metabolites have been demonstrated to be implicated in immune functions of vertebrates, fish, and insects. Thus, the aim of this study was to assess the impact of ArA supplementation on the FA composition and hemocyte parameters of oysters Crassostrea gigas. Oyster dietary conditioning consisted of direct addition of ArA solutions at a dose of 0, 0.25, or 0.41 mu g ArA per mL of seawater into tanks in the presence or absence of T-Iso algae. Results showed significant incorporation of ArA into gill polar lipids when administered with algae (up to 19.7%) or without algae (up to 12.1%). ArA supplementation led to an increase in hemocyte numbers, phagocytosis, and production of reactive oxygen species by...
Tipo: Text
Palavras-chave: Hemocyte parameters; Oyster immunity; Arachidonic Acid; Poly unsaturated fatty acids; Nutrition; Bivalve; Crassostrea gigas.
Ano: 2006
URL: http://archimer.ifremer.fr/doc/2006/publication-1876.pdf