Consulta: subjectFacets:"Bactéries"
Registros recuperados: 15
Data/hora: 13/06/2024 13:57:43

Apports nutritifs et bactériens en estuaire de Penzé. Année 2000
Provedor de dados: 5
Autores: Piriou, Jean-yves; Droit, Julie.
L'estuaire de la Penzé (nord-Finistère, France) est le siège de plusieurs dysfonctionnements de type biologique (eutrophisation et contaminations bactériennes) qui nécessitent une bonne connaissance et un suivi des apports d'origine terrigène susceptibles d'influencer ou de provoquer ces phénomènes. Une étude sur ce secteur test a permis la mise au point d'une méthodologie de suivi des apports à l'estuaire. Celle-ci se fait en quatre étapes: 1. Inventaire des paramètres de suivi des apports. • Dans le cas de la prolifération des macroalgues du genre ulva et des microalgues toxiques Alexandrium minutum, les différents apports nutritifs azotés, phosphorés et siliceux ont été mesurés. • Dans le cas de la contamination des mollusques bivalves d'ostréiculture...
Tipo: Text
Palavras-chave: Apports; Bactéries; Bassins versants; Contamination; Eutrophisation marine; Rejets; Sels nutritifs.
Ano: 2001
URL: http://archimer.ifremer.fr/doc/00105/21660/19241.pdf

Influence de l'environnement trophique de l'élevage en biofloc sur les performances physiologiques de la crevette Litopenaeus stylirostris : Étude de paramètres de la nutrition, de l'immunité et de la reproduction
Provedor de dados: 5
Autores: Cardona, Emilie.
Biofloc is an intensive rearing system with zero or minimal water exchange where a diverse population of microorganisms (microalgae, zooplankton and bacteria) develops in association with organic matter to form the floc particles. These particles play the double role of biological filter and dietary supplement. This dissertation aims to better understand the process of this rearing system and its interactions with the Litopenaeus stylirostris shrimp. Two specific objectives were integrated within the framework of this general objective: (i) to measure the production gain from biofloc rearing and (ii) to study the interaction between biofloc environment and shrimp and to assess its role on production performances of shrimps. Thus, our results show...
Tipo: Text
Palavras-chave: Biofloc; Crevette; Nutrition; Stress oxydant; Défenses antioxydantes; Immunité; Reproduction; Oeufs; Larves; Bactéries; Microbiote; Biofloc; Shrimp; Nutrition; Oxidative stress; Antioxidant defences; Immunity; Reproduction; Eggs; Larvae; Bacteria; Microbiota.
Ano: 2015
URL: http://archimer.ifremer.fr/doc/00272/38294/36492.pdf

Qualité microbiologique des coquillages destinés à la consommation humaine : contamination des coquillages par des bactéries pathogènes pour l’homme. Sous-région marine Golfe de Gascogne. Evaluation initiale DCSMM.
Provedor de dados: 5
Autores: Hervio-heath, Dominique; Gourmelon, Michele; Catherine, Martial.
Tipo: Text
Palavras-chave: Golfe de Gascogne; Coquillages; Contamination microbiologique; Bactéries; Pathogènes; Suivi.
Ano: 2012
URL: https://archimer.ifremer.fr/doc/00329/44061/43632.pdf

Evolution des caractéristiques chimiques et biologiques des sédiments en circuit clos. I. Azote et populations bactériennes en fonction de certains paramètres du milieu
Provedor de dados: 5
Autores: Chamroux, S.; Boucher, G.
Chemical and Biological evolution of sediments in closed circuit : I. Nitrogen and bacteria. A series of well controlled sea water closed circuit sand filters al­lowed the study of chemical and biological regulation processes in the sediment. Bacteria, Nitrogen chemistry and meiofauna were mainly investigated. The evolution of the different forms of nitrogen is rather similar, whatever the organic matter flow in the sediment. As long as the amount of or­ganic input works as limiting factor, bacteria densities are proportional to its flow. No correlation was found between bacteria and chemical parameters in the sand or in the water. The temperature does not seem to play a determinant part neither in the evolution of bacteria nor in the mineralization of...
Tipo: Text
Palavras-chave: Circuit clos; Sédiment; Bactéries; Matière organique; Azote; Closed circuit; Sediment; Bacteria; Organic matter; Nitrogen.
Ano: 1979
URL: http://archimer.ifremer.fr/doc/00305/41652/40861.pdf

Sulfate-reducing bacteria [rom mangrove swamps II : Their ecology and physiology
Provedor de dados: 5
Autores: Bharathi, Pal; Oak, S; Chandramohan, D.
Sulfate-reducing bacteria (SRB) have been enumerated and physiologically characterized in three mangrove stations along the Zuari estuary. The substrates for counting were lactate, acetate, propionate, butyrate and benzoate. Benzoate oxidizing SRB were widespread and occurred in numbers up to 6.62 x 10(3)/g dry sediment. The next highest in number were lactate utilizing SRB. On an average there were more propionate and butyrate utilizers than acetate utilizers. While Agasaim at the mouth of the estuary harboured highest number of lactate oxidizers, none were detected at Mirabaug upstream during the samplings. The SRB shared many characteristics with Desulfovibrio desulfuricans, D. desulfuricans aestuarii, D. salexigens, Desulfotomaculum orientis, D....
Tipo: Text
Palavras-chave: Bactéries; Sulfato-réductrices; Estuaire; Sédiments; Mangrove; Mangrove-Bacteria; Sulfate-reducers; Estuary; Sediments.
Ano: 1991
URL: http://archimer.ifremer.fr/doc/00323/43395/43103.pdf

Dynamique du phosphore et rôle comme facteur limitant de la production planctonique dans le panache de la Gironde sur le plateau continental Sud Gascogne
Provedor de dados: 5
Autores: Labry, Claire.
This study was supported by the Atlantic working site of the « Programme National d’Océanographie Côtière » (PNOC, PNEC since 1999). The objectives were (1) to check the existence and to understand the mechanisms of winter phytoplankton blooms in the bay of Biscay influenced by the Gironde waters (2) to determine the limiting nutrient of the primary production associated to these blooms and to follow the seasonal evolution of the limiting nutrient, (3) to understand the consequences of this early limitation on the structuration of algal populations in spring. Since phosphorus was supposed to be the major limiting nutrient of algal growth in the Gironde plume, the different forms of the phosphorus cycle as well as the bacterial compartment, central in this...
Tipo: Text
Palavras-chave: Golfe de Gascogne; Gironde; Phytoplancton; Bactéries; Phosphates; Phosphore organique; Dissous; Phosphatases; Bay of Biscay; Gironde; Phytoplankton; Bacteria; Phosphate; Dissolved organic phosphorus; Phosphatases.
Ano: 2001
URL: http://archimer.ifremer.fr/doc/00013/12463/9298.pdf

Interaction de la bactérie Vibrio harveyi avec son hôte, l'hormeau Haliotis tuberculata : approches physiologiques, cellulaires et moléculaires
Provedor de dados: 5
Autores: Travers, Marie-agnes.
Abalone aquaculture only recently developed in western Europe, but already it has to face numerous pathologies. Since 1998, the natural and farm stocks of Haliotis tuberculata suffer regularly high mortalities, mainly due to the pathogenic bacterium, Vibrio harveyi. The vibriosis of the European abalone, in particular its macroscopic signs, and the conditions necessary for its development have been studied in detail by field and laboratory experiments. We have been able to show the importance of the interplay between water temperature (&gt;17°C), animal physiology (reproduction period) and a pathogenic strain (harbouring the plasmid pVCR1) for the development of this abalone disease. A limited localisation study of the abalone target tissues (gills, muscle...
Tipo: Text
Palavras-chave: Ormeau; Haliotis tuberculata; Bactéries; Vibrio harveyi; Vibriose; Température; Immunité; Reproduction; Hémocytes; MAP Kinases; Plasmide; Virulence; GFP; Abalone; Haliotis tuberculata; Bacteria; Vibrio harveyi; Vibriosis; Temperature; Immunity; Reproduction; Haemocytes; MAP Kinases; Plasmid; Virulence; GFP.
Ano: 2008
URL: http://archimer.ifremer.fr/doc/00176/28729/27196.pdf

Interactions microalgues-bactéries en système expérimental bispécifique : effets sur la croissance de Dunaliella sp.
Provedor de dados: 5
Autores: Le Chevanton, Myriam.
The use of algae-bacteria mixed culture has been suggested to improve performance of industrial microalgae culture. The present study aims to investigate impact of selected bacteria on Dunaliella sp. growth. 97 bacteria strains were isolated from a variety of marine microalgae cultures. The diversity of strains revealed members of α-and γ-proteobacteria, Cytophaga-Flavobacterium-Bacteroides and grampositive. A two-phase approach was then implemented to select bacteria that improve Dunaliella sp. growth, using an original high-throughput experimental device. Although a majority of bacteria induced performance reduction for Dunaliella sp., some resulted in significant improvements. In nitrogenlimited batch culture, the Alteromonas sp. bacteria demonstrated a...
Tipo: Text
Palavras-chave: Interactions; Microalgues; Bactéries; Dunaliella; Axénie; Interactions; Microalgae; Bacteria; Dunaliella; Axenic.
Ano: 2013
URL: http://archimer.ifremer.fr/doc/00187/29839/28291.pdf

Caractérisation de la virulence d'une souche de Vibrio aestuarianus, pathogène de l'huître Crassostrea gigas
Provedor de dados: 5
Autores: Labreuche, Yannick.
In France. shellfish production is a traditional. well-established industry. mainly based upon commercial farming of the Pacifie oyster. Crassostrea gigas. Since the 1980's, annual mass mortalities of C. gigas have been reported during summer. Several studies on this subject have demonstrated that these mortality outbreaks resulted from complex interactions between the physiologieal andJor genetic status of the oysters. environmental factors, and one or more infectious agents, among which are bacteria of the genus Vibrio.
Tipo: Text
Palavras-chave: Huître; Crassostrea gigas; Bactéries; Vibrio aestuarlanus; Pathogénicité; Produits extracellulaires; Métalloprotéase; Hémocytes; Interactions hôte/pathogène; Oyster; Crassostrea gigas; Bacteria; Vibrio aestuarianus; Pathogenicity; Extracellular products; Metalloprotease; Hemocytes; Host/pathogen interactions.
Ano: 2006
URL: http://archimer.ifremer.fr/doc/00034/14561/11859.pdf

La qualité des eaux dans l'Estuaire de la Gironde. 1- Traitement des données. 2 - Synthèse
Provedor de dados: 5
Autores: Maurice, Laurence.
The main problem of the Girond estuary is a pollution by the cadmium. During this last ten years, the good quality of the water is proved by the analysis of the main physico - chemical and biochemical parameters and bacteria. But since 1989, straight to the Blayais power station, the BOD5 varied between 2 and 3,5 mg.l-1 and a diminution of the dissolved oxygen has been observed; it's probably caused by the accumulation of biodegradable organic matter in the maximum turbidity zone during years characterized by low river flows. For average river flow, urban discharges takes part for 20 % in total fluxes of BD05; in 1991, this part attempts 35 %. During the last 7 years, the pluriannual evolution of the nitrate concentrations measured in the Garonne river...
Tipo: Text
Palavras-chave: Oxygène; Sels nutritifs; Matière organique; Bactéries; Apports; Estuaire Gironde; Oxygen; Nutrients; Organic matter; Bacteria; Fluxes; Gironde estuary.
Ano: 1993
URL: http://archimer.ifremer.fr/doc/00037/14855/12178.pdf

Dynamique des populations bactériennes au cours de deux productions expérimentales de phytoplancton marin naturel
Provedor de dados: 5
Autores: Bianchi, M.a.; Martin, Y.p.
Quantitative and qualitative variations of the hetero­trophic bacterial population, during two experimental induced phytoplanktonic blooms are described. When the phytoplanktonic population deceases, the bacte­rial population exhibits a significant increase. The spring microflore is quite different from the fall ones. Microbiological, physiological and biochemical fluctuations indicate qualitative fluctuations. Bacterial strains are identified as "bacterial profiles".
Tipo: Text
Palavras-chave: Plancton; Bactéries; Dynamique; Physiologie; Structure; Plankton; Bacteria; Dynamic; Physiology; Structure.
Ano: 1979
URL: http://archimer.ifremer.fr/doc/00305/41669/40878.pdf

Etude comparative entre la microflore de l'appareil digestif de Teredo navalis L. (Teredinidae-bivalvia) et les population bactériennes de son environnement
Provedor de dados: 5
Autores: Martinez, J-c.
333 bacterial strains were isolated from the digestive tract of shipworms, their burrows and the surrounding sea water, using two culture media (2216E and T.C.B.S.). Samples were taken in the Bay of Brest in february, march and april 1980. The bacterial isolates were described using 109 ecological, biochemical and nutri­tional tests in order to discuss the origin and function of the Teredo navalis L. gut microflora.
Tipo: Text
Palavras-chave: Teredo navalis L.; Bactéries; Appareil digestif.
Ano: 1982
URL: http://archimer.ifremer.fr/doc/00306/41747/40958.pdf

Etude de la structure des communautés bactériennes du sédiment et de l'écologie de Vibrio aestuarianus pathogène de l'huître creuse Crassostrea gigas dans deux sites ostréicoles
Provedor de dados: 5
Autores: Azandegbe, Afi.
Since several years, the French oyster farming copes with high mortality affecting juveniles and some adults of the Pacific oyster Crassostrea gigas. Studies conducted in the framework of a multidisciplinary project (MOREST) showed that mortality was related to several factors like physiological and genetic status of oyster, pathogens including bacteria of the genus Vibrio, and revealed that the sediment, on which the oyster cages are installed, might play a particular role. This has been suggested because of the concomitance of the mortalities and increased toxic compounds like ammonia and sulphides in the sediment. Moreover, the presence of Vibrio bacteria in the sediment indicates a dual role of sediment in the mortality onset. The physico-chemical...
Tipo: Text
Palavras-chave: Huître; Crassostrea gigas; Bactéries; Vibrio aestuarianus; Écologie; Sédiment; Ammonium; Sulfures; Oyster; Crassostrea gigas; Bacteria; Vibrio aestuarianus; Ecology; Sediment; Ammonia; Sulphide.
Ano: 2010
URL: http://archimer.ifremer.fr/doc/00032/14277/11561.pdf

Etude d'oligosaccharides bioactifs issus d'exopolysaccharides bactériens : obtention, caractérisation et relation structure/fonction
Provedor de dados: 5
Autores: Roger, Olivier.
Unusual exopolysaccharides (EPS) produced by heterotrophic aerobic and mesophilic bacteria originating from hydrothermal vent, were reviewed as a new source of polysaccharidic structures endowed with innovative biological properties. The first step of this study was the structure determination of the EPS GY785, synthesized by Alteromonas infernus. A highly branched nonasaccharidic repetitive unit was identified using chemical modifications and nuclear magnetic resonance spectroscopy. This 106 g/mol polysaccharide is composed of glucose, galactose, glucuronic acid, galacturonic acid, and contains a single branched ramification and one sulphate group.  The second step was the preparation of low molecular weight bioactive polysaccharides presenting interest...
Tipo: Text
Palavras-chave: Phosphorylation; Sulphation; Depolymerization; NMR spectroscopy; Structure; Deep sea hydrothermal vent; Bacteria; Exopolysaccharides; Activité anticoagulante; Phosphatation; Sulfatation; Dépolymérisation; Spectroscopie de RMN; Structure; Sources hydrothermales; Bactéries; Exopolysaccharides.
Ano: 2002
URL: http://archimer.ifremer.fr/doc/2002/these-622.pdf

Seasonal variability in microplanktonic biomasses in the Gironde dilution plume (Bay of Biscay): relative importance of bacteria
Provedor de dados: 5
Autores: Artigas, Lf.
Bacterial and phytoplankton biomasses were estimated in a four-year study along a saline gradient (the dilution plume of the Gironde estuary on the Aquitanian continental shelf), by measuring bacterial abundance and mean cell volumes (epifluorescence counts) and chlorophyll-a concentrations tin vitro fluorescence). The spatial and temporal distribution of phytoplankton enabled us to determine the seasonal succession of algal blooms, sprouting in the marine waters of the inner shelf in early spring (picoplanktonic forms), reaching their annual maximum (10 mu g L-1) in plume waters in advanced spring, and moving to estuarine waters in the summer (&gt; 20 mu m forms). Bacterial biomasses followed mainly a decreasing dilution gradient, especially in winter and...
Tipo: Text
Palavras-chave: Bactéries; Phytoplancton; Rapport des biomasses microbiennes; Variabilité saisonnière; Panache de dilution girondin; Bacterioplankton; Phytoplankton; Microbial biomass ratio; Seasonal variability; Gironde dilution plume.
Ano: 1998
URL: http://archimer.ifremer.fr/doc/00325/43659/43210.pdf