Consulta: creatorFacets:"Bianchi, M"
Registros recuperados: 4
Data/hora: 07/06/2024 09:43:15

Comparaison de methodes directes (microscopiques) et indirectes (par mise en culture) dans l'evaluation d'une pollution bacterienne d'origine fecale. Etude preliminaire
Provedor de dados: 5
Autores: Munro, P; Bianchi, M.
Cells of two serotypes of Escherichia coli (O26B6 and 0111B4) were counted using epifluorescence and immunofluorescence microscopy (nonavalent serum) and plate count on specific medium. Values from indirect counts were 10 fold smaller than those from both microscopic counts. In a sample of sea water from an area receiving a fecal pollution, the highest number of bacteria was obtained by epifluorescence microscopy. In that case, the number of cells counted by immunofluorescence microscopy was 10 fold smaller than the number of bacteria able to grow on the medium. It could be due to: the diversity of the natural community, the possibility to other bacteria than E. coli to grow on the used culture medium, the restrictiveness of the serum for "pathogenic...
Tipo: Text
Palavras-chave: Escherichia coli; Bacteria; Microbiological culture; Pathogenic bacteria; Microbial contamination; Bacterial counters; Fluorescence microscopy; Bacteria collecting devices; Indicator species.
Ano: 1984
URL: http://archimer.ifremer.fr/doc/1984/acte-1001.pdf

Evolution de la communaute bacterienne heterotrophe de l'eau de mer lors d'une experience d'aquaculture de crevettes peneides en systemes clos
Provedor de dados: 5
Autores: Sohier, L; Bianchi, M.
The quantitative and qualitative evolution of the heterotrophic bacterial community of sea water was studied throughout an experimental rearing of Penaeus japonicus in closed systems. Cluster analysis was realised on 417 strains coming from water sampled at different moments of the experiment. This collection includes 40 strains coming from a mussel used for diet and 40 strains coming from the digestive tract of one prawn after six months rearing. Quantitative and qualitative studies have both shown a similar evolution of heterotrophic microflora whatever the initial animal load was. The dendrogram obtained led to a description of characteristics of the various populations constituting the heterotrophic bacterial community of the water environment...
Tipo: Text
Palavras-chave: Penaeus japonicus; Malacostraca; Bacteria; Recirculating systems; Numerical taxonomy; Temporal variations; Microorganisms; Shrimp culture; Heterotrophic organisms.
Ano: 1984
URL: http://archimer.ifremer.fr/doc/1984/acte-972.pdf

Transfert et mineralisation de la matiere organique azotee a travers les deux premiers echelons de la micro communaute heterotrophe
Provedor de dados: 5
Autores: Vanwambeke, F; Bianchi, M.
Bacterial response to organic (amino acids) or inorganic (NH sub(4) super(+)) nitrogen was studied in 350 liter closed batch systems. The experiments demonstrate an important NH sub(4) super(+) remineralization associated with bacterial growth. The differences between substrate and bacterial C/N ratios and bacterial metabolic demands partly explain the high values of ammonia produced. Grazing by heterotrophic microflagellates resulted in an important release of NH sub(4) super(+). This suggests and important role of grazers for the nitrogen remineralization in natural waters.
Tipo: Text
Palavras-chave: Flagellata; Ciliata; Bacteria; Plankton; Heterotrophic organisms; Ammonia; Amino acids; Nitrogen cycle; Mineralization.
Ano: 1984
URL: http://archimer.ifremer.fr/doc/1984/acte-986.pdf

Influence of shellfish farming activities on nitrification, nitrate reduction to ammonium and denitrification at the water-sediment interface of the Thau lagoon, France
Provedor de dados: 5
Autores: Gilbert, F; Souchu, Philippe; Bianchi, M; Bonin, P.
The seasonal patterns of nitrification, denitrification and dissimilatory ammonium production (DAP) rates were studied in the sediment of 2 stations in the Thau lagoon (south of France). The station ZA was located within the shellfish farming zone and the station B was the reference site. A marked effect of shellfish fanning on bacterial activities was observed. Spatial differences were associated with discrepancies in the organic content and the reduction state of sediments, i.e. highest reductive processes (denitrification and DAP) were noted in shellfish farming area, whereas the oxidative process (nitrification) was predominant outside the farming zone. At both stations, the DAP activity increased in September (autumn) concomitant with an increase of...
Tipo: Text
Palavras-chave: Shellfish farming; Nitrogen bacterial processes; Nitrification; Nitrate reduction to ammonium; Denitrification; Thau lagoon; Mediterranean Sea; Sediment-water exchanges.
Ano: 1997
URL: http://archimer.ifremer.fr/doc/00070/18145/15697.pdf