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Determination of reduced sulfur compounds by high-performance liquid chromatography in hydrothermal seawater and body fluids from Riftia pachyptila ArchiMer
Gru, Cecile; Sarradin, Pierre-marie; Legoff, Hélène; Narcon, Sandrine; Caprais, Jean-claude; Lallier, Francois.
This paper describes a method for the determination of reduced sulfur compounds in hydrothermal seawater and body fluids from the hydrothermal tube worm Riftia pachyptila. Sulfur is a hey component of the hydrothermal ecosystem based on chemosynthesis, Sulfur compounds were derivatized at pH 8 (4.3 for sulfide in biological fluid) with a fluorescent reagent, monobromobimane, and separated by reverse-phase HPLC. The eluted compounds were detected by spectrofluorimetry. This method allowed: the quantitative analysis of sulfide, sulfite, thiosulfate, cysteine and glutathione in seawater, vascular blood and coelomic fluids from R, pachyptila, The detection limits were in the 0.1 mu mol l(-1) range with a precision lower than 10%, The method has been applied to...
Tipo: Text Palavras-chave: Sulfide; Sulfite; Thiosulfate; Cysteine; Glutathione; Hydrothermal seawater; Riftia pachyptila; Biological fluids.
Ano: 1998 URL: http://archimer.ifremer.fr/doc/00186/29763/28203.pdf
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Impact of Oyster Farming on Diagenetic Processes and the Phosphorus Cycle in Two Estuaries (Britanny, France) ArchiMer
Andrieux, Francoise; Azandegbe, Afi; Caradec, Florian; Philippon, Xavier; Kerouel, Roger; Youenou, Agnes; Nicolas, Jean-louis.
This study aims to compare the impact of oyster cultures on diagenetic processes and the phosphorus cycle in the sediments of the Aber Benoît and the Rivière d’Auray, estuary of Brittany, France. Our results showed clear evidence of the seasonal impact of oyster cultures on sediment characteristics (grain size, organic matter parameters), and the phosphorus cycle, especially in the Aber Benoît. At this site, seasonal variations of sulfide and Fe concentrations in pore waters, as well as Fe-P concentrations in the solid-phase highlighted a shift from a system governed by iron reduction (Reference) to a system governed by sulphate reduction (Beneath Oyster). This could be partly explained by the increase in labile organic matter (ie, biodeposits) beneath...
Tipo: Text Palavras-chave: Sediment; Phosphorus; Sulfide; Dissolved Fe/P ratios; Labile organic matter; Oyster cultures.
Ano: 2014 URL: http://archimer.ifremer.fr/doc/00209/32003/30441.pdf
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Is temperature a good proxy for sulfide in hydrothermal vent habitats? ArchiMer
Le Bris, Nadine; Rodier, Philippe; Sarradin, Pierre-marie; Le Gall, Christian.
On the basis of previous studies at 9 degrees N and 13 degrees N East Pacific Rise (EPR) fields, we discuss the general assumption that temperature is a proxy for sulfide in vent fauna habitat. The main conclusion of these works is illustrated here through selected examples. In situ measurements were used to assess the variability of chemical parameters as function of temperature at the scale of fauna aggregations. Over a single vent site, aggregations of mussels or Riftia pachyptila discretely distributed around diffuse vents exhibit, in first assumption, similar sulfide-temperature correlation. In contrast, sulfide is much higher, for a given temperature, in the habitat of alvinellids than in neighboring habitats of Riftia pachyptila. Some consistency in...
Tipo: Text Palavras-chave: Alvinellids; Riftia pachyptila; Mussel beds; Temperature; Sulfide; Hydrothermal vent.
Ano: 2006 URL: http://archimer.ifremer.fr/doc/2006/publication-3609.pdf
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On the early fate of hydrothermal iron at deep-sea vents: A reassessment after in situ filtration ArchiMer
Waeles, Mathieu; Cotte, Laura; Pernet-coudrier, Benoit; Chavagnac, V.; Cathalot, Cecile; Leleu, T.; Laes-huon, Agathe; Perhirin, Antoine; Riso, R. D.; Sarradin, Pierre-marie.
Deep-sea hydrothermal venting is now recognized as a major source of iron (Fe), an essential trace element that controls marine productivity. However, the reactions occurring during dispersal from buoyant plumes to neutrally buoyant hydrothermal plumes are still poorly constrained. Here we report for the first time on the dissolved-particulate partition of Fe after in situ filtration at the early stage of mixing at different hydrothermal discharges, i.e., Lucky Strike (37 degrees N), TAG (26 degrees N), and Snakepit (23 degrees N) on the Mid-Atlantic Ridge. We found that hydrothermal iron is almost completely preserved (>90%) in the dissolved fraction, arguing for low iron-bearing sulfide precipitation of iron in basalt-hosted systems with low Fe:H2S...
Tipo: Text Palavras-chave: Hydrothermal; Iron; Sulfide; Venting; Filtration; Precipitation.
Ano: 2017 URL: https://archimer.ifremer.fr/doc/00388/49944/50522.pdf
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Presence and diversity of anammox bacteria in cold hydrocarbon-rich seeps and hydrothermal vent sediments of the Guaymas Basin ArchiMer
Russ, Lina; Kartal, Boran; Op Den Camp, Huub J. M.; Sollai, Martina; Le Bruchec, Julie; Caprais, Jean-claude; Godfroy, Anne; Damste, Jaap S. Sinninghe; Jetten, Mike S. M..
Hydrothermally active sediments are highly productive, chemosynthetic areas which are characterized by the rapid turnover of particulate organic matter under extreme conditions in which ammonia is liberated. These systems might be suitable habitats for anaerobic ammonium oxidizing (anammox) bacteria but this has not been investigated in detail. Here we report the diversity and abundance of anammox bacteria in sediments that seep cold hydrocarbon-rich fluids and hydrothermal vent areas of the Guaymas Basin in the Cortes Sea using the unique functional anammox marker gene, hydrazine synthase (hzsA). All clones retrieved were closely associated to the "Candidatus Scalindua" genus. Phylogenetic analysis revealed two distinct clusters of hzsA sequences (Ca....
Tipo: Text Palavras-chave: Anammox; HzsA; AprA; Hydrothermal vents; Cold seep; Sulfide.
Ano: 2013 URL: http://archimer.ifremer.fr/doc/00180/29156/27555.pdf
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Role of pockmarks in diversity and species assemblages of coastal macrobenthic communities ArchiMer
Dubois, Stanislas; Derian, Francois; Caisey, Xavier; Rigolet, Carinne; Caprais, Jean-claude; Thiebaut, Eric.
We used existing bathymetric data to study the macrofauna of a geophysical pockmark field restricted to a benthic habitat engineered by the tubiculous amphipod Haploops nirae in South Brittany (France). Stations inside and outside pockmarks of different morphometric characteristics (location, size, depression depth) were sampled for macrofauna and environmental parameters (sediment characteristics, organic matter, chl a, hydrogen sulfide and methane concentrations). Diversity indices showed higher species richness inside pockmarks, especially for species with medium to high abundances. Most sediment cores showed low methane but high hydrogen sulfide concentrations. We hypothesised that after eruption, the remaining residual methane from pockmark sediments...
Tipo: Text Palavras-chave: Benthic habitat; Biodiversity; Succession; Amphipod; Haploops; South Brittany; Sulfide; Methane; Environmental factors.
Ano: 2015 URL: https://archimer.ifremer.fr/doc/00272/38333/36576.pdf
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Selection of sulfur oxidizing bacterium for sulfide removal in sulfate rich wastewater to enhance biogas production Electron. J. Biotechnol.
Kantachote,Duangporn; Charernjiratrakul,Wilawan; Noparatnaraporn,Napavarn; Oda,Kohei.
Sulfur oxidizing bacteria (SOB) were isolated and tested in order to remove sulfide from high sulfate wastewater to reduce the amount of hydrogen sulfide (H2S) in the produced biogas. A promising SOB isolate, designated as isolate T307, was selected due to its best sulfide removal (86.7%) in the effluent of a sulfate reduction reactor (SRR) over a 24 hrs incubation. The bacterium was able to grow better as a mixotroph (yeast extract as a carbon source) than as a chemolithoautotroph. In addition, as a heterotroph, the bacterium grew well with yeast extract and peptone. Based on partial 16S rRNA gene sequence, the isolated T307 was an Alcaligenes sp. and was able to convert most of sulfide species (total sulfide: TS; dissolved sulfide: DS and H2S) into...
Tipo: Journal article Palavras-chave: Biodesulfurization; Biogas; Effluent from a sulfate reduction reactor; Sulfide.
Ano: 2008 URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582008000200013
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Sulfide determination in hydrothermal seawater samples using a vibrating gold micro-wire electrode in conjunction with stripping chronopotentiometry ArchiMer
Aumond, Virginie; Waeles, Mathieu; Salaun, Pascal; Gibbon-walsh, Kristoff; Van Den Berg, Constant M. G.; Sarradin, Pierre-marie; Riso, Ricardo D..
A rapid electrochemical stripping chronopotentiometric procedure to determined sulfide in unaltered hydrothermal seawater samples is presented. Sulfide is deposited at -0.25 V (vs Ag/AgCl, KCl 3 M) at a vibrating gold microwire and then stripped through the application of a reductive constant current (typically -2 mu A). The hydrodynamic conditions are modulated by vibration allowing a short deposition step, which is shown here to be necessary to minimize H2S volatilization. The limit of detection (LOD) is 30 nM after a deposition step of 7s. This LOD is in the same range as the most sensitive cathodic voltammetric technique using a mercury drop electrode and is well below those reported previously for other electrodes capable of being implemented in situ....
Tipo: Text Palavras-chave: Sulfide; Stripping chronopotentiometry; Vibrating electrode; Gold; Seawater; Hydrothermal.
Ano: 2012 URL: http://archimer.ifremer.fr/doc/00111/22222/20065.pdf
Registros recuperados: 8
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