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Diversité chimique et bactéries associées à Spongia officinalis, une éponge marine accumulatrice de métaux / Chemical diversity and bacteria associated with the marine sponge Spongia officinalis, a metal bioaccumulatorBauvais, Cléa 04 March 2015 (has links)
L’accumulation des métaux toxiques dans l’environnement représente une forte menace environnementale et sanitaire. Les éponges marines, invertébrés sessiles qui filtrent activement l’eau de mer environnante, peuvent concentrer des composés toxiques comme les métaux lourds (Pérez et al., 2005) et être utilisés comme bioindicateurs de pollution métallique (Patel et al., 1985). Elles hébergent une biomasse bactérienne importante (Websterand Taylor, 2012), dont le rôle dans la séquestration de polluants environnementaux reste encore mal connu.Notre étude s’est portée sur les bactéries tolérantes aux métaux lourds (Cu2+, Pb2+, Ni2+ etZn2+) associées à l’éponge méditerranéenne Spongia officinalis (classe : Demospongia, ordre :Dictyoceratida, famille : Spongiidae) connue pour son accumulation de métaux toxiques(Pérez et al., 2005). Nous avons d’abord développé une étude de la communauté bactérienne associée à l’éponge S. officinalis récoltée dans un environnement pollué en métaux par la combinaison d’approches moléculaire (DGGE, CARD-FISH) et culturale. Afin de comprendre les mécanismes d’accumulation et/ou de résistance vis‐à‐vis des métaux d’une souche de Pseudovibrio sp. isolée de S. officinalis pour sa tolérance au cuivre nous avons développé des approches combinées de protéogénomique (électrophorèse bidimensionnelle,séquençage du génome) et de microscopie (microscopie électronique à balayage couplée à une analyse élémentaire EDX). Enfin, la diversité chimique associée à l’éponge S. officinalis,sa variabilité spatiale et temporelle ont ensuite été caractérisées par couplage d’analyse chromatographique et de spectrométrie de masse (LC-MS, LC-MS/MS). / The accumulation of toxic metals in the environment is a strong environmental and health threat. Marine sponges are sessile invertebrates that actively filter the surrounding seawater.They can concentrate toxic compounds such as heavy metals (Perez et al. 2005) and are used as bioindicators of metal pollution (Patel et al. 1985). They host an important bacterial biomass (Webster and Taylor 2011), whose role in the sequestration of environmental pollutants is still unclear.Our study focused on bacteria tolerant to heavy metals (Cu2+, Pb2+, Ni2+, Zn2+) associated with the Mediterranean sponge Spongia officinalis (class: Demospongia, order Dictyoceratida,family: Spongiidae) known for its accumulation of toxic metals (Perez et al. 2005). We first developed a study of bacterial community associated with the sponge S. officinalis harvested in a metal polluted environment by the combination of cultural and molecular approaches(DGGE, CARD-FISH). The mechanisms of accumulation and/or resistance to copper of a sponge isolated strain, Pseudovibrio sp. was investigated by combined approaches of proteogenomics (two-dimensional electrophoresis, sequencing of the genome) and microscopy (scanning electron microscopy coupled with elemental analysis EDX). A final approach was developed to characterize the chemical diversity associated with this sponge and spatial and temporal variability by coupling chromatographic analysis and mass spectrometry (LC-MS, LC-MS/MS).
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Effects of polycyclic musks and bisphenol A on the settlement and metamorphosis on sponge, Spongia ceylonensisChen, Shiang-Ting 05 September 2011 (has links)
Sponge population partly depends on larval recruitment. Environmental
factors, e.g. light, salinity, pH and temperature, chemical factors and pollution
may influence larval settlement and metamorphosis. In this study, the effects
of galaxolide¡]HHCB¡^¡Btonalide¡]AHTN¡^and bisphenol A¡]BPA¡^on the
settlement and metamorphosis of an intertidal sponge ¡]Spongia ceylonensis¡^
were examined. The experiments included LC50 test, effects of solvent,
HHCB, AHTN and BPA on sponge settlement and metamorphosis. In the
LC50 tests, the 96 hr¡VLC50 value of HHCB and AHTN all greater than 1.00
mg/L, and the 96 hr¡VLC50 of BPA was 0.58 mg/L. Acetone concentration
(1.00 mg/L ) in this study didn¡¦t affect sponge settlement and metamorphosis.
Effect of HHCB and AHTN on sponge settlement and metamorphosis
concentrations of 0.13, 0.25, 0.50 and 1.00 mg/L was insignificant. In
contrast, the settlement rate was decrease by 20 % at treatment of 1.00 mg/L
BPA. The metamorphosis rates were also decrease by 20 % and 80 % at
concentrations of 0.50 mg/L and 1.00 mg/L BPA. In conclusion, the toxicity
of AHTN was greater than that of HHCB to sponge settlement and
metamorphosis.
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The study of filtration efficiency of two intertidal sponges to four algal powdersTang, Mu-ting 16 February 2011 (has links)
The present study was undertaken to evaluate the filtration efficiency of the bath sponge Spongia ceylonensis (Spongiidae) and fire sponge Tedania klausi (Tedaniidae) collected from Penghu. In the feeding experiements, live and algal powder of Tetraselmis chui (8-16£gm), Chaetoceros muelleri (6-9£gm), Isochrysis galbana (3-7£gm) and Nannochloropsis oculata (2-5£gm) were used to determine the clearance rate of sponges. Sponges S. ceylonensis and T. klausi showed selective feeding under various algal species, concentrations and conditions (live algae or powders). After 90 minutes, the clearance rate of T. klausi fed on N. oculata powder was 71 ml h-1 gDW-1 at algal concentration of 107 cells ml-1, but S. ceylonensis didn¡¦t feed at the same concentration. At 106 cells ml-1 concentrations, the clearance rate of S. ceylonensis fed on live I. galbana was 538 ml h-1 gDW-1 which was higher than T. klausi, i.e. 11 ml h-1 gDW-1. At 105 cells ml-1 concentrations, the clearance rate of T. klausi fed on live T. chui was 431 ml h-1 gDW-1 which was higher than S. ceylonensis, i.e. 23 ml h-1 gDW-1. At 104 cells ml-1 concentrations, S. ceylonensis fed on live T. chui with clearance rate 532 ml h-1 gDW-1, and T. klausi was 315 ml h-1 gDW-1. The results showed differential clearance rates of sponges depend on sponge species, algal species, concentrations and conditions (live or powder). In gerneral, sponge clearance rate is higher when feeds on live algae than algal powders. Although the filtration efficiency of algal powders is low, the advantage of low cost and high accessibility still make algal powder highly competitive in sponge aquaculture industry.
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Estudo do processo de biossorção do corante Preto Reativo 5 utilizando a macrófita Limnobium spongia / Study of biosorption process of Reactive Black 5 dye using macrophyte Limnobium spongiaSuzaki, Pedro Yahico Ramos 20 February 2013 (has links)
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Previous issue date: 2013-02-20 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / This work aimed to study the removal of dye Reactive Black 5 using as biosorbent macrophyte Limnobium spongia. It was investigated the influence of milling the biomass, the particle size, the chemical pretreatment adsorbent with the solution of NaOH 0.1 mol L¬-1 and H2SO4 0.1 mol L-1 , the stirring speed and also the influence of temperature and pH parameters. It was also determined adsorption kinetics and equilibrium. In the study of the influence of grinding, it was observed that the biomass of ground Limnobium spongia showed better results in the adsorption of the dye than the entire biomass. The different particle sizes and pretreatment of biomass tested did not influence significantly the removal of the dye. In the study stirring rate was observed that from 100 rpm external diffusional resistances are reduced to a minimum. The parameters pH and temperature were studied jointly by the method Central Composite Rotatable Design (CCRD), behavior demonstrated that these parameters are independent and greater amount of dye removed occurred at the maximum temperature 49.8°C and at pH 0.8. The kinetic study was made at temperatures of 20 and 50° C, the maximum amount of dye removed and the equilibrium time was of 81.97 mg g-1 and 6 h to 20°C and 105.6 mg g-1 and 4 h to 50°C. The kinetic data were best represented by pseudo-second order model. The equilibrium isotherms were performed at temperatures of 20, 30, 40 and 50º C. The highest removal of dye was 108.17 mg g-1 at 50°C and amount removed was 86 mg g-1 at 20°C. The equilibrium data of isotherms at all temperatures were predicted by the Langmuir model. / Este trabalho teve como objetivo estudar a remoção do corante Preto Reativo 5 utilizando como biossorvente a macrófita Limnobium spongia. No estudo da biossorção do corante, foram investigadas a influência da moagem da biomassa, o tamanho da partícula, o pré-tratamento químico do adsorvente com soluções de NaOH 0,1 mol L¬-1 e H2SO4 0,1 mol L¬-1, a velocidade de agitação e também a influência dos parâmetros temperatura e pH. Foram determinadas a cinética de adsorção e o equilíbrio. No estudo da influência da moagem, observou-se que a biomassa de Limnobium spongia moída obteve melhores resultados na adsorção do corante do que a biomassa inteira. As diferentes granulometrias e pré-tratamentos da biomassa testadas não influenciaram de forma significativa na remoção do corante. No estudo da velocidade de agitação observou-se que a partir de 100 rpm as resistências difusionais externas foram reduzidas ao seu valor mínimo. Os parâmetros pH e temperatura foram estudados de forma conjunta através do método de Delineamento Composto Central Rotacional (DCCR) e o resultado demonstrou que estes parâmetros são independentes e que a maior quantidade de corante removida aconteceu na temperatura máxima testada 49,8ºC e no pH 0,8 (mínimo testado). O estudo cinético foi realizado nas temperaturas de 20 e 50ºC, a quantidade máxima de corante removido e o tempo de equilíbrio foram de 81,97 mg g-1¬¬ e 6 h para 20º e 105,6 mg g-1¬¬ e 4 h para 50ºC. Os dados cinéticos foram melhor representados pelo modelo cinético de pseudo-segunda ordem. As isotermas de equilíbrio foram avaliadas nas temperaturas de 20, 30, 40 e 50ºC. O maior valor de remoção de corante foi de 108,2 mg g-1 na isoterma de 50ºC, enquanto que a quantidade máxima removida foi de 86 mg g-1 na isoterma de 20ºC. Os dados de equilíbrio das isotermas apresentaram comportamento previsto pelo modelo de Langmuir.
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