Consulta: creatorFacets:"Grzebyk, Daniel"
Registros recuperados: 9
Data/hora: 05/06/2024 17:07:19

Le phytoplancton nuisible des côtes de France. De la biologie à la prévention
Provedor de dados: Institutional Archive of Ifreme (ArchiMer)
Autores: Belin, Catherine; Berland, Brigitte; Erard-le Denn, Evelyne; Gentien, Patrick; Grzebyk, Daniel; Marcaillou Le Baut, Claire; Lassus, Patrick; Partensky, Frédéric.
Several phyloplankton species, whelher hloom-forming or not, have caused jish kilts or human intoxications or other nuisances on the coasts of France for the past ten years. The present review considers them under the foltowing aspects: morphology, cytology, physiology, hiochemislry, geographical distrihution, ecological requirements, toxicity and/or nuisances. These are principally the Dinoflagellates Dinophysis spp., Gymnodinium cf nagasakiense (= Gyrodinium cf aureolum) and Alexandrium minutum, and the Prymnesiophyte Phaeocystis spp. .. in addition, Ihree presumahly toxic species which were recently found on the French coasts are examined, namely : the Dinoflageltates Prorocentrum minimum and Gymnodinium spirale and the Silicoflageltate Dictyocha. Toxic...
Tipo: Text
Ano: 1991
URL: https://archimer.ifremer.fr/doc/1991/rapport-4210.pdf

Influence of Environmental Factors on the Paralytic Shellfish Toxin Content and Profile of Alexandrium catenella (Dinophyceae) Isolated from the Mediterranean Sea
Provedor de dados: Institutional Archive of Ifreme (ArchiMer)
Autores: Laabir, Mohamed; Collos, Yves; Masseret, Estelle; Grzebyk, Daniel; Abadie, Eric; Savar, Veronique; Sibat, Manoella; Amzil, Zouher.
Laboratory experiments were designed to study the toxin content and profile of the Alexandrium catenella strain ACT03 (isolated from Thau Lagoon, French Mediterranean) in response to abiotic environmental factors under nutrient-replete conditions. This dinoflagellate can produce various paralytic shellfish toxins with concentrations ranging from 2.9 to 50.3 fmol/cell. The toxin profile was characterized by carbamate toxins (GTX3, GTX4 and GTX5) and N-sulfocarbamoyl toxins (C1, C2, C3 and C4). C2 dominated at 12-18 degrees C, but only for salinities ranging from 10 to 25 psu, whereas GTX5 became dominant at temperatures ranging from 21 to 30 degrees C at almost all salinities. There was no significant variation in the cellular toxin amount from 18 degrees C...
Tipo: Text
Palavras-chave: Alexandrium catenella; PSP toxins; Temperature; Salinity; Light.
Ano: 2013
URL: http://archimer.ifremer.fr/doc/00148/25969/24056.pdf

Viability, growth and toxicity of Alexandrium catenella and Alexandrium minutum (Dinophyceae) following ingestion and gut passage in the oyster Crassostrea gigas
Provedor de dados: Institutional Archive of Ifreme (ArchiMer)
Autores: Laabir, Mohamed; Amzil, Zouher; Lassus, Patrick; Masseret, Estelle; Tapilatu, Yosmina; De Vargas, Romain; Grzebyk, Daniel.
Adult oysters Crassostrea gigas were experimentally fed with Alexandrium catenella and Alexandrium minutum which are responsible for recurrent toxic blooms in French coastal waters. C. gigas produced faeces and pseudofaeces containing intact and viable temporary pellicular cysts of these two Paralytic toxin producing species. When incubated in favourable conditions, these pellicular cysts were able to germinate at high rates (between 74 and 94%) and the resulting vegetative cells divided with growth rates close to the non-ingested cells (control). The toxin profile of the vegetative cells originated from the germinated temporary cysts was analyzed by liquid chromatography/ fluorescence detection. Total toxin content of newly germinated cells was lower than...
Tipo: Text
Palavras-chave: Paralytic shellfish poisoning; Oysters; Cysts; Alexandrium minutum; Alexandrium catenella.
Ano: 2007
URL: http://archimer.ifremer.fr/doc/2007/publication-2622.pdf

Dinophysis spp. cells concentrated from nature for experimental purposes, using size fractionation and reverse migration
Provedor de dados: Institutional Archive of Ifreme (ArchiMer)
Autores: Maestrini, Serge Y; Berland, Brigitte R; Grzebyk, Daniel; Spano, Anna-maria.
A method based on size fractionation plus reverse phototactic migration was used to collect large Dinophysis spp.-dominated populations. Cells were active and survived handling and transportation. Experiments involving various treatments for establishing permanent cultures are described; none have yet been successful.
Tipo: Text
Palavras-chave: Dinophysis; Dense-cell suspension; Attempted culture.
Ano: 1995
URL: http://archimer.ifremer.fr/doc/00258/36956/35627.pdf

Phosphorus limitation might promote more toxin content in the marine invader dinoflagellate Alexandrium minutum
Provedor de dados: Institutional Archive of Ifreme (ArchiMer)
Autores: Maestrini, Serge; Bechemin, Christian; Grzebyk, Daniel; Hummert, Christian.
Alexandrium minutum (strain AM89BM) has been grown in semi-continuous culture (0.2 vol. d super(-1)) in N-limiting (NO sub(3) super(-): PO sub(4) super(3-)=1.6 and 3.16), in P-limiting (N: P=160 and 80), and in N and P balanced (N: P=16) media. The toxin content in cells changed greatly according to the N: P ratio. Cells grown in N: P balanced condition showed an average total paralytic shellfish poisoning (PSP) content of 1.24 fmol cell super(-1). In N-limiting conditions, cells contained ca. 3 times less toxin with mean values of 0.41-0.45 fmol cell super(-1). In contrast, cells grown in P-limiting conditions contained on average 3.5 and 7 times more toxins than in the balanced N: P condition: 4.31 fmol cell super(-1) in the N: P=160 medium and 8.01 fmol...
Tipo: Text
Palavras-chave: Alexandrium minutum; Phosphorus limitation; Toxin content; PSP.
Ano: 2000
URL: http://archimer.ifremer.fr/doc/00173/28422/26753.pdf

Nuisances et intoxications causées en France par le phytoplancton et les "efflorescences" marines - Synthèse préliminaire
Provedor de dados: Institutional Archive of Ifreme (ArchiMer)
Autores: Sournia, A.; Belin, Catherine; Berland, B.; Erard-le Denn, Evelyne; Grzebyk, Daniel; Marcaillou-le Baut, Claire; Lassus, Patrick; Partensky, F.
Les intoxications humaines résultant de la consommation de coquillages sont connues en France depuis plusieurs siècles. On peut supposer que la cause principale a d'abord été d'origine bactériologique, eu égard aux conditions de transport et à l'absence de contrôles de salubrité dans le passé. Quoi qu'il en soit, il faut compter aujourd'hui avec une autre origine, à savoir les proliférations de certaines algues unicellulaires planctoniques (phytoplancton), qui causent dans notre pays jusqu'à plusieurs milliers d'intoxications par an. Soulignons que la France a été jusqu'ici largement épargnée, puisque d'autres pays comptabilisent des dizaines ou centaines de décès depuis le début du siècle. On vient toutefois de découvrir la présence dans nos eaux côtières...
Tipo: Text
Ano: 1990
URL: http://archimer.ifremer.fr/doc/00069/18017/15569.pdf

Stimulation of nitrogen-fixing cyanobacteria in a Baltic Sea plankton community by land-derived organic matter or iron addition
Provedor de dados: Institutional Archive of Ifreme (ArchiMer)
Autores: Stolte, Willem; Balode, Maija; Carlsson, Per; Grzebyk, Daniel; Janson, Sven; Lips, Inga; Panosso, Renata; Ward, Clive J.; Graneli, Edna.
In the Baltic Sea, floating blooms of nitrogen-fixing cyanobacteria occur yearly during late summer. These blooms can sometimes be limited by iron. Due to extensive foresting around the Baltic Sea, iron is entering the Baltic Sea partly bound to dissolved organic material (DOM) via rivers. An experiment was performed in 300 1 laboratory mesocosms to test the hypothesis that riverine high-molecular weight dissolved organic matter (HMWDOM), extracted by tangential flow filtration &gt; 1000 Da, stimulates the biomass of nitrogen-fixing cyanobacteria, by increasing the availability of iron. The addition of iron/EDTA and of DOM resulted in 5 to 10 times higher biomass of nitrogen-fixing cyanobacteria. Accordingly, higher primary production and particulate...
Tipo: Text
Palavras-chave: Mesocosm experiment; Humic acid; HMWDOM; High molecular weight dissolved organic matter; Iron; Nitrogen fixation; Cyanobacteria.
Ano: 2006
URL: http://archimer.ifremer.fr/doc/2006/publication-2470.pdf

Observations on possible life cycle stages of the dinoflagellates Dinophysis cf. acuminata, Dinophysis acuta and Dinophysis pavillardi
Provedor de dados: Institutional Archive of Ifreme (ArchiMer)
Autores: Berland, Brigitte R; Maestrini, Serge Y; Grzebyk, Daniel.
Some aspects of the life-cycle have been investigated in Dinophysis cf, acuminata, the dominant species of the genus along the French Atlantic coast, as well as in D, acuta; a few observations have also been made on the Mediterranean species D. pavillardi. Dinophysis cells occur in 2 clearly distinguished sizes. Small cells typically had a theca thinner than large cells, and cingular and sulcal lists were less developed. Both small and large cells were seen dividing, producing 1 to 4 round intracellular bodies. Some of these round bodies in turn contained many small flagellated cells which escaped through a pore and swam rapidly. Their behaviour after release, and how they might give rise to vegetative cells, has not been observed thus far; we do not...
Tipo: Text
Palavras-chave: Dinophysis sp.; Life cycle; Cyst.
Ano: 1995
URL: http://archimer.ifremer.fr/doc/00258/36957/35626.pdf

Recent aspects of nutrition in the dinoflagellate Dinophysis cf. acuminata
Provedor de dados: Institutional Archive of Ifreme (ArchiMer)
Autores: Berland, Brigitte R; Maestrini, Serge Y; Grzebyk, Daniel; Thomas, Pierre.
No species of Dinophysis has yet been cultured in the full sense. To determine the photosynthetic capability in D. cf. acuminata, the dominant morphotype of the genus along the French Atlantic coast, we took material from natural populations, in some trials by pipetting out single cells, and in others using plankton assemblages enriched in D. cf, acuminata by size fractionation and reverse sedimentation. Inorganic carbon uptake was measured at temperatures from 11 to 23 degrees C and at a light intensity of 400 mu mol photons m(-2) s(-1). Total uptake was proportional to the number of cells and increased linearly with incubation time, the uptake rate showing a distinct maximum at 18 degrees C, while at 23 degrees C being only half this maximum....
Tipo: Text
Palavras-chave: Dinophysis cf. acuminata; Nutrition; Ultrastructure.
Ano: 1995
URL: http://archimer.ifremer.fr/doc/00258/36958/35624.pdf