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Partager le résultat de cette recherche Interroger des sources externesÉtude des mécanismes de résistance de bactéries endophytes isolées à partir des racines d’Hedysarum pallidum et de Lygeum spartum poussant sur des déblais de mine d’antimoine. / Mounia Kassa Laouar ép Chouikh
Titre : Étude des mécanismes de résistance de bactéries endophytes isolées à partir des racines d’Hedysarum pallidum et de Lygeum spartum poussant sur des déblais de mine d’antimoine. Type de document : texte imprimé Auteurs : Mounia Kassa Laouar ép Chouikh, Auteur ; Aicha Mechakra (Née Maza), Directeur de thèse ; Oualida Rached-Mosbah, Directeur de thèse Mention d'édition : 09/07/2020 Editeur : جامعة الإخوة منتوري قسنطينة Année de publication : 2020 Importance : 183 f. Format : 30 cm. Note générale : 1 copies imprimées disponibles
Langues : Français (fre) Catégories : Français - Anglais
BiologieTags : Biochimie et Biologie Cellulaire et Moléculaire: Biochimie-Microbiologie appliquée bactéries endophytes métalloïdes stress oxydatif H2O2 MDA proline enzymes
antioxydantes biofilm transformation résistance bacterial endophytes metalloids oxidative stress antioxidant enzymes resistance البكتيريا الداخلية المعادن الثقيلة الإجهاد التأكسدي H2O2البرولين إنزيمات مضادات الأكسدة المقاومة التحولIndex. décimale : 570 Sciences de la vie. Biologie Résumé :
This work focuses on the study of the endophytic bacterial flora of H. pallidum and L. spartum roots, growing on the soil of mining region polluted by Sb and As, and the determination of the physiological, biochemical and molecular defense mechanisms adopted by this microflora to fight against metallic stress. The morphological and biochemical analyzes reveal a high biodiversity of this endophytic microflora. The study of the Sb and As toxicity allows the selection of two strains having the highest MICs, namely 450 mM of Sb and 175 mM of As. The molecular identification of resistant strains via 16S RNA gene sequencing shows that they are identical and belong to the Serratia marcescens species with 99% homology. The batch culture in presence of gradual Sb and As concentrations reveals a progressive decrease in bacterial growth of the two strains. Moreover, the measurement of oxidative stress parameters indicates a significant increase in the H2O2 amount, the MDA amount, the intracellular proline and even the activities of antioxidant enzymes, except at high thresholds in Sb and As. These enzymes permit the detoxification of the bacteria by elimination of the H2O2 and the other free radicals generated by metallic stress. In addition, the study of the resistance of S. marcescens strains to a range of heavy metals and antibiotics shows multiple resistance to nickel and cobalt, as well as to kanamycin, ampicillin and chloramphenicol. To cope with the presence of Sb and As, S. marcescens has adopted life in group mode and form biofilms to reduce their toxicity. The molecular study of the resistance mechanisms of the two strains, using cell transformation methods, reveals that the genetic determinants responsibles for the resistance of S. marcescens to metalloids are carried mainly by the chromosome.Note de contenu : Annexes. Diplôme : Doctorat en sciences En ligne : ../theses/biologie/KAS7638.pdf Format de la ressource électronique : Permalink : index.php?lvl=notice_display&id=11472 Étude des mécanismes de résistance de bactéries endophytes isolées à partir des racines d’Hedysarum pallidum et de Lygeum spartum poussant sur des déblais de mine d’antimoine. [texte imprimé] / Mounia Kassa Laouar ép Chouikh, Auteur ; Aicha Mechakra (Née Maza), Directeur de thèse ; Oualida Rached-Mosbah, Directeur de thèse . - 09/07/2020 . - جامعة الإخوة منتوري قسنطينة, 2020 . - 183 f. ; 30 cm.
1 copies imprimées disponibles
Langues : Français (fre)
Catégories : Français - Anglais
BiologieTags : Biochimie et Biologie Cellulaire et Moléculaire: Biochimie-Microbiologie appliquée bactéries endophytes métalloïdes stress oxydatif H2O2 MDA proline enzymes
antioxydantes biofilm transformation résistance bacterial endophytes metalloids oxidative stress antioxidant enzymes resistance البكتيريا الداخلية المعادن الثقيلة الإجهاد التأكسدي H2O2البرولين إنزيمات مضادات الأكسدة المقاومة التحولIndex. décimale : 570 Sciences de la vie. Biologie Résumé :
This work focuses on the study of the endophytic bacterial flora of H. pallidum and L. spartum roots, growing on the soil of mining region polluted by Sb and As, and the determination of the physiological, biochemical and molecular defense mechanisms adopted by this microflora to fight against metallic stress. The morphological and biochemical analyzes reveal a high biodiversity of this endophytic microflora. The study of the Sb and As toxicity allows the selection of two strains having the highest MICs, namely 450 mM of Sb and 175 mM of As. The molecular identification of resistant strains via 16S RNA gene sequencing shows that they are identical and belong to the Serratia marcescens species with 99% homology. The batch culture in presence of gradual Sb and As concentrations reveals a progressive decrease in bacterial growth of the two strains. Moreover, the measurement of oxidative stress parameters indicates a significant increase in the H2O2 amount, the MDA amount, the intracellular proline and even the activities of antioxidant enzymes, except at high thresholds in Sb and As. These enzymes permit the detoxification of the bacteria by elimination of the H2O2 and the other free radicals generated by metallic stress. In addition, the study of the resistance of S. marcescens strains to a range of heavy metals and antibiotics shows multiple resistance to nickel and cobalt, as well as to kanamycin, ampicillin and chloramphenicol. To cope with the presence of Sb and As, S. marcescens has adopted life in group mode and form biofilms to reduce their toxicity. The molecular study of the resistance mechanisms of the two strains, using cell transformation methods, reveals that the genetic determinants responsibles for the resistance of S. marcescens to metalloids are carried mainly by the chromosome.Note de contenu : Annexes. Diplôme : Doctorat en sciences En ligne : ../theses/biologie/KAS7638.pdf Format de la ressource électronique : Permalink : index.php?lvl=notice_display&id=11472 Exemplaires (1)
Code-barres Cote Support Localisation Section Disponibilité KAS/7638 KAS/7638 Thèse Bibliothèque principale Thèses Disponible
Titre : Elimination des polluants organiques par méthodes physicochimiques et photochimiques en milieux aqueux. : Cas de l’éthyle violet et du rouge congo (séparés et mélangés) et de la monochloramine Type de document : texte imprimé Auteurs : Abdessemed Ala, Auteur ; Kamel Djebbar, Auteur Editeur : جامعة الإخوة منتوري قسنطينة Année de publication : 2016 Importance : 224 f. Format : 30 cm. Note générale : 2 copies imprimées disponibles
Langues : Français (fre) Catégories : Français - Anglais
ChimieTags : Éthyle Violet Rouge Congo Mochloramine TiO2 Charbon actif ZnO Adsorption Rayonnement UV Photolyse H2O2 NaOCl •OH Ethyl violet Congo red Monochloramine Activated carbon UV radiation Photolysis Violet Ethyle) (Congo Rouge) المونوكلرمين (NH2Cl) (PC500 TiO2) كربون منشط (ZnO) إدمصاص أشعة فوق بنفسجية (H2O2) (NaOCl) (•OH ) (•Cl) Index. décimale : 540 Chimie et sciences connexes Résumé : The aim of this research is to study the decolorization of two dyes separated and in a mixture by physico-chemical processes (adsorption, TiO2 and CA-ZnO) and photocatalytic processes like: TiO2/UV and CA-ZnO/UV. Another study has been led on the degradation of Monocloramine in homogeneous phase via direct UV photolysis, H2O2/UV and
NaOCl/UV. Treated separately, both dyes have shown an appreciable adsorption on the two supports and that this process is well represented by an apparent kinetic of order 2.
Besides, Congo Red and Ethyl Violet are described by isotherms of type L and S respectively and that process is also well represented by the model of Langmuir for Ethyl Violet and Redlish-Peterson of Congo Red. On the other hand, the photocatalytic system led via TiO2/UV has been efficient toward both dyes and this process follows an apparent
rate constant of order 1. In another part, this process is well described by the kinetic model of Langmuir-Hinshelwood and that oxidation process occurs, mainly, in surface. The inhibition process has been demonstrated by alcohols proving thereby that radicals •OH are the main oxidation route. The photoproducts issued from the decolorization of the two dyes have been identified using masse spectroscopy technic. This has permitted to establish a mechanism of degradation for the two dyes. Same efficiency is obtained using CAZnO/UV process (CA: activated carbon issued from olive cakes). In another side and in the mixture, the treatment of the two dyes by both systems has, shown that the efficiency decreases as the concentration of the other added dye increases. Indeed, the addition of the second substrate slows down the disappearance speed of the other. The kinitics model
remained unchanged for the two processes (2nd order for adsorption and 1 st order for photocatalysis) The last part treats the degradation of the Monochloramine which occurs via direct UV photolysis in presence of two lamps:
BP (254 nm) and MP (200-600 nm).
The obtained results have been significant. Furthermore, these results have been greatly enhanced mainly by H2O2/UV. However, for NaOCl/UV system we could mention that the disappearance rate slows down because of the formation of photoproducts such as: Mono, Di and Trichloramines. Moreover, the process is well described by an apparent kinetic of order 1 and those photoproducts identified in H2O2/UV, NaOCl/UV and direct photolysis systems are nitrates and nitritesDiplôme : Doctorat en sciences En ligne : ../theses/chimie/ALA6959.pdf Format de la ressource électronique : Permalink : index.php?lvl=notice_display&id=10358 Elimination des polluants organiques par méthodes physicochimiques et photochimiques en milieux aqueux. : Cas de l’éthyle violet et du rouge congo (séparés et mélangés) et de la monochloramine [texte imprimé] / Abdessemed Ala, Auteur ; Kamel Djebbar, Auteur . - جامعة الإخوة منتوري قسنطينة, 2016 . - 224 f. ; 30 cm.
2 copies imprimées disponibles
Langues : Français (fre)
Catégories : Français - Anglais
ChimieTags : Éthyle Violet Rouge Congo Mochloramine TiO2 Charbon actif ZnO Adsorption Rayonnement UV Photolyse H2O2 NaOCl •OH Ethyl violet Congo red Monochloramine Activated carbon UV radiation Photolysis Violet Ethyle) (Congo Rouge) المونوكلرمين (NH2Cl) (PC500 TiO2) كربون منشط (ZnO) إدمصاص أشعة فوق بنفسجية (H2O2) (NaOCl) (•OH ) (•Cl) Index. décimale : 540 Chimie et sciences connexes Résumé : The aim of this research is to study the decolorization of two dyes separated and in a mixture by physico-chemical processes (adsorption, TiO2 and CA-ZnO) and photocatalytic processes like: TiO2/UV and CA-ZnO/UV. Another study has been led on the degradation of Monocloramine in homogeneous phase via direct UV photolysis, H2O2/UV and
NaOCl/UV. Treated separately, both dyes have shown an appreciable adsorption on the two supports and that this process is well represented by an apparent kinetic of order 2.
Besides, Congo Red and Ethyl Violet are described by isotherms of type L and S respectively and that process is also well represented by the model of Langmuir for Ethyl Violet and Redlish-Peterson of Congo Red. On the other hand, the photocatalytic system led via TiO2/UV has been efficient toward both dyes and this process follows an apparent
rate constant of order 1. In another part, this process is well described by the kinetic model of Langmuir-Hinshelwood and that oxidation process occurs, mainly, in surface. The inhibition process has been demonstrated by alcohols proving thereby that radicals •OH are the main oxidation route. The photoproducts issued from the decolorization of the two dyes have been identified using masse spectroscopy technic. This has permitted to establish a mechanism of degradation for the two dyes. Same efficiency is obtained using CAZnO/UV process (CA: activated carbon issued from olive cakes). In another side and in the mixture, the treatment of the two dyes by both systems has, shown that the efficiency decreases as the concentration of the other added dye increases. Indeed, the addition of the second substrate slows down the disappearance speed of the other. The kinitics model
remained unchanged for the two processes (2nd order for adsorption and 1 st order for photocatalysis) The last part treats the degradation of the Monochloramine which occurs via direct UV photolysis in presence of two lamps:
BP (254 nm) and MP (200-600 nm).
The obtained results have been significant. Furthermore, these results have been greatly enhanced mainly by H2O2/UV. However, for NaOCl/UV system we could mention that the disappearance rate slows down because of the formation of photoproducts such as: Mono, Di and Trichloramines. Moreover, the process is well described by an apparent kinetic of order 1 and those photoproducts identified in H2O2/UV, NaOCl/UV and direct photolysis systems are nitrates and nitritesDiplôme : Doctorat en sciences En ligne : ../theses/chimie/ALA6959.pdf Format de la ressource électronique : Permalink : index.php?lvl=notice_display&id=10358 Exemplaires (1)
Code-barres Cote Support Localisation Section Disponibilité ALA/6959 ALA/6959 Thèse Bibliothèque principale Thèses Disponible
Titre : Etude comparative de la dégradation de colorants de la famille des triphénylméthanes par voies photochimique et sonochimique en solution aqueuse homogène et hétérogène. Type de document : texte imprimé Auteurs : Seyfeddine Bendjabeur, Auteur ; Razika Zouaghi, Directeur de thèse Mention d'édition : 10-mars-19 Editeur : جامعة الإخوة منتوري قسنطينة Année de publication : 2019 Importance : 251 f. Format : 30 cm. Note générale : Doctorat 3éme CYCLE LMD.
1 copies imprimées disponibles
Langues : Français (fre) Catégories : Français - Anglais
ChimieTags : Chimie: Chimie Analytique et Environnement Colorant adsorption Photolyse Procédés d’Oxydations Avancée H2O2 UV TiO2 Photocatalyse sonolyse dye photolysis advanced oxidation processes photocatalysis sonolysis صبغ امتزاز تحلل ضوئي عمليات أكسدة متطورة 2H20 الأشعة فوق البنفسجية و تحفيز ضوئي تحلل صوتي Index. décimale : 540 Chimie et sciences connexes Résumé : This study focused on the elimination of three dyes by several advanced sonochemical and photochemical oxidation processes in a homogeneous and heterogeneous medium as well as by direct photolysis at 254 and 365 nm. In most of the cases studied, a pseudo-first order kinetic law applies correctly to a large part of the reactions. The results obtained in this study indicated that photolysis (UV only) was found to have little effect on the degradation of the three dyes. The removal efficiency can be improved by increasing the intensity of the photonic flux or by decreasing the initial concentration of pollutant.
The coupling of H2O2/UV increases considerably the degradation rate of the three dyes, the efficiency is enhanced by raising the dose of H2O2 up to a limit imposed by the self-inhibition reactions. The DT-DFT method allowed recalculating the theoretical UV-Visible spectra of the three dyes which are comparable to that obtained experimentally. Adsorption and heterogeneous Photocatalysis were influenced by various factors (initial substrate concentration, catalyst type and loading, pH of the solution, addition of hydrogen peroxide, and the presence of inorganic salts). The results showed that the degradation yield of the three dyes is very high when using TiO2-P25, where a complete photocatalytic degradation of 10 mg L-1 of GV, BF and AF was obtained in 25, 30 and 50 minutes in the presence of 1 g L-1 of TiO2 Degussa P25 at natural pH. First-order kinetics described the photocatalytic reaction of the three substrates andthe Langmuir-Hinshelwood model correctly described the photocatalysis processes of the substrates tested. The comparison between various types of catalysts (Degussa P25, Millenium PC500, PC105, PC100, and PC50) gave varied results but Degussa P25 was the most efficient photocatalyst from which it was chosen for this study. The optimum catalyst concentration was 1 g L-1 of TiO2 with an initial concentration of 10 mg L-1 of dye. Finally, the sonochemical degradation of GV by sonolysis at 516 kHz shows that this method is effective for the degradation of this dye. However, this process can be affected by several parameters including, applied electrical power, initial substrate concentration, pHof the solution, the addition of H2O2 and S2O82- and the presence of someinorganic ions.Note de contenu : Annexe.
Diplôme : Doctorat En ligne : ../theses/chimie/BEN7567.pdf Format de la ressource électronique : Permalink : index.php?lvl=notice_display&id=11405 Etude comparative de la dégradation de colorants de la famille des triphénylméthanes par voies photochimique et sonochimique en solution aqueuse homogène et hétérogène. [texte imprimé] / Seyfeddine Bendjabeur, Auteur ; Razika Zouaghi, Directeur de thèse . - 10-mars-19 . - جامعة الإخوة منتوري قسنطينة, 2019 . - 251 f. ; 30 cm.
Doctorat 3éme CYCLE LMD.
1 copies imprimées disponibles
Langues : Français (fre)
Catégories : Français - Anglais
ChimieTags : Chimie: Chimie Analytique et Environnement Colorant adsorption Photolyse Procédés d’Oxydations Avancée H2O2 UV TiO2 Photocatalyse sonolyse dye photolysis advanced oxidation processes photocatalysis sonolysis صبغ امتزاز تحلل ضوئي عمليات أكسدة متطورة 2H20 الأشعة فوق البنفسجية و تحفيز ضوئي تحلل صوتي Index. décimale : 540 Chimie et sciences connexes Résumé : This study focused on the elimination of three dyes by several advanced sonochemical and photochemical oxidation processes in a homogeneous and heterogeneous medium as well as by direct photolysis at 254 and 365 nm. In most of the cases studied, a pseudo-first order kinetic law applies correctly to a large part of the reactions. The results obtained in this study indicated that photolysis (UV only) was found to have little effect on the degradation of the three dyes. The removal efficiency can be improved by increasing the intensity of the photonic flux or by decreasing the initial concentration of pollutant.
The coupling of H2O2/UV increases considerably the degradation rate of the three dyes, the efficiency is enhanced by raising the dose of H2O2 up to a limit imposed by the self-inhibition reactions. The DT-DFT method allowed recalculating the theoretical UV-Visible spectra of the three dyes which are comparable to that obtained experimentally. Adsorption and heterogeneous Photocatalysis were influenced by various factors (initial substrate concentration, catalyst type and loading, pH of the solution, addition of hydrogen peroxide, and the presence of inorganic salts). The results showed that the degradation yield of the three dyes is very high when using TiO2-P25, where a complete photocatalytic degradation of 10 mg L-1 of GV, BF and AF was obtained in 25, 30 and 50 minutes in the presence of 1 g L-1 of TiO2 Degussa P25 at natural pH. First-order kinetics described the photocatalytic reaction of the three substrates andthe Langmuir-Hinshelwood model correctly described the photocatalysis processes of the substrates tested. The comparison between various types of catalysts (Degussa P25, Millenium PC500, PC105, PC100, and PC50) gave varied results but Degussa P25 was the most efficient photocatalyst from which it was chosen for this study. The optimum catalyst concentration was 1 g L-1 of TiO2 with an initial concentration of 10 mg L-1 of dye. Finally, the sonochemical degradation of GV by sonolysis at 516 kHz shows that this method is effective for the degradation of this dye. However, this process can be affected by several parameters including, applied electrical power, initial substrate concentration, pHof the solution, the addition of H2O2 and S2O82- and the presence of someinorganic ions.Note de contenu : Annexe.
Diplôme : Doctorat En ligne : ../theses/chimie/BEN7567.pdf Format de la ressource électronique : Permalink : index.php?lvl=notice_display&id=11405 Exemplaires (1)
Code-barres Cote Support Localisation Section Disponibilité BEN/7567 BEN/7567 Thèse Bibliothèque principale Thèses Disponible
Titre : Contribution de methodes destructives (Photolyse et P.O.A's) et non destructives à l'élimination de deux colorants (Bleu de methylène et rouge Congo) en solution aqueuse Type de document : texte imprimé Auteurs : Oualid Baghriche ; Univ. de Constantine, Éditeur scientifique ; K.E. Djebbar, Directeur de thèse Année de publication : 2005 Importance : 133 f. Note générale : 01 Disponible à la salle de recherche 02 Disponibles au magazin de la bibliothèque centrale 01 CD Langues : Français (fre) Catégories : Français - Anglais
ChimieTags : Adsorption Photolyse Rayonnement UV Charbon actif Sels H2O2 BM+ S2O8 deus moins et alcools Index. décimale : 540 Chimie et sciences connexes En ligne : ../theses/chimie/BAG4234.pdf Permalink : index.php?lvl=notice_display&id=3728 Contribution de methodes destructives (Photolyse et P.O.A's) et non destructives à l'élimination de deux colorants (Bleu de methylène et rouge Congo) en solution aqueuse [texte imprimé] / Oualid Baghriche ; Univ. de Constantine, Éditeur scientifique ; K.E. Djebbar, Directeur de thèse . - 2005 . - 133 f.
01 Disponible à la salle de recherche 02 Disponibles au magazin de la bibliothèque centrale 01 CD
Langues : Français (fre)
Catégories : Français - Anglais
ChimieTags : Adsorption Photolyse Rayonnement UV Charbon actif Sels H2O2 BM+ S2O8 deus moins et alcools Index. décimale : 540 Chimie et sciences connexes En ligne : ../theses/chimie/BAG4234.pdf Permalink : index.php?lvl=notice_display&id=3728 Exemplaires (1)
Code-barres Cote Support Localisation Section Disponibilité BAG/4234 BAG/4234 Thèse Bibliothèque principale Thèses Disponible
Titre : Etude de la degradation par voie photochimique de polluant organique « Orange G » en milieu aqueux homogene et heterogene Type de document : texte imprimé Auteurs : Halima Chenini, Auteur ; Kamel Djebbar, Directeur de thèse Editeur : Constantine : Université Mentouri Constantine Année de publication : 2012 Importance : 164 f. Format : 31 cm. Note générale : Doctorat en sciences
2 copies imprimées disponiblesLangues : Français (fre) Catégories : Français - Anglais
ChimieTags : Photodégradation Procédés d’Oxydations Avancées Fenton H2O2 S2O82- Photocatalyse Index. décimale : 540 Chimie et sciences connexes Diplôme : Doctorat en sciences En ligne : ../theses/chimie/CHE6207.pdf Format de la ressource électronique : Permalink : index.php?lvl=notice_display&id=6176 Etude de la degradation par voie photochimique de polluant organique « Orange G » en milieu aqueux homogene et heterogene [texte imprimé] / Halima Chenini, Auteur ; Kamel Djebbar, Directeur de thèse . - Constantine : Université Mentouri Constantine, 2012 . - 164 f. ; 31 cm.
Doctorat en sciences
2 copies imprimées disponibles
Langues : Français (fre)
Catégories : Français - Anglais
ChimieTags : Photodégradation Procédés d’Oxydations Avancées Fenton H2O2 S2O82- Photocatalyse Index. décimale : 540 Chimie et sciences connexes Diplôme : Doctorat en sciences En ligne : ../theses/chimie/CHE6207.pdf Format de la ressource électronique : Permalink : index.php?lvl=notice_display&id=6176 Exemplaires (1)
Code-barres Cote Support Localisation Section Disponibilité CHE/6207 CHE/6207 Thèse Bibliothèque principale Thèses Disponible
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