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Partager le résultat de cette recherche Interroger des sources externesContribution à l'étude de la diversité des bactéries thermophiles de quelques environnements chauds algériens et essai de de production et de caractérisation de leurs protéases extracellulaires. / Mohamed Amine Gomri
Titre : Contribution à l'étude de la diversité des bactéries thermophiles de quelques environnements chauds algériens et essai de de production et de caractérisation de leurs protéases extracellulaires. Type de document : texte imprimé Auteurs : Mohamed Amine Gomri, Auteur ; Karima Kharroub, Directeur de thèse Editeur : جامعة الإخوة منتوري قسنطينة Année de publication : 2019 Importance : 308 f. Format : 30 cm. Note générale : 2 copies imprimées disponibles
Langues : Français (fre) Catégories : Français - Anglais
Nutrition, Alimentation et Technologies Agro-AlimentairesTags : Biotechnologie:Sciences Alimentaires environnements chauds algériens diversité bactéries thermophiles protéases extracellulaires Algerian hot environments diversity bacteria thermophilic extracellular
proteases بينات ساخنة جزائرية تنوع-بكتيريا محبة للحرارة بروتياز خارج الخليةIndex. décimale : 640 Industrie Alimentaire Résumé :
Natural hot environments can represent an important source of microbial biodiversity and biomolecules with great added value. Among these biomolecules, extracellular hydrolases and in particular proteases are of great interest for the food industry because of their single reactional properties at high temperatures and their stability in various environmental conditions. The primary objective of this thesis is the isolation of thermophilic aerobic bacteria with extracellular proteolytic activities from 7 sites representing different Algerian hot environments: three geothermal sources, two Saharan soils, a sebkha and an oil field. On the
138 isolates selected on the basis of their macroscopic and microscopic morphological characters, 53 isolates able to degrade casein and/or gelatin on solid culture media were characterized by amplified ribosomal DNA restriction analysis. After the elimination of clones, 28 strains were identified by sequencing and analyzing their 16S rRNA genes. These strains belong to 5 genera of aerobic thermophilic endospore-forming bacteria: Anoxybacillus, Bacillus, Geobacillus, Brevibacillus and Thermoactinomyces. The physiological and biochemical characterization of these strains confirm the relationship with these genera. The genomes of two strains, Geobacillus Sah69 and Thermoactinomyces AS95, were then characterized. The production of putative extracellular proteases of industrial interest was revealed. In addition, the biodiversity of the geothermal sources of Debagh and Ouled Ali was studied by metagenomic analysis of the 16S rRNA hypervariable V4 region sequences of environmental DNA collected from sediment samples. The thermophilic aerobic bacterial communities dominate the two sites with a minor presence of the phylum of Firmicutes and the genera isolated by cultural methods. Lastly, the production of extracellular proteases was estimated quantitatively for the 28 selected strains. Study of production kinetics and effect of fermentation conditions on three selected strains, Geobacillus Sah69, Thermoactinomyces AS95 and Brevibacillus OA30, were then carried out. After the extraction of the supernatant, two proteases, metalloprotease 32- F38 and serine-protease 16-F39, were produced and purified from strain Brevibacillus OA30. These proteases were acid, thermoactive and had a great stability in presence of SDS, solvents and other chemical agents tested. Thus revealing a good potential for industrial application.Note de contenu :
Annexes.Diplôme : Doctorat en sciences En ligne : ../theses/agronomie/GOM7444.pdf Format de la ressource électronique : Permalink : https://bu.umc.edu.dz/md/index.php?lvl=notice_display&id=11222 Contribution à l'étude de la diversité des bactéries thermophiles de quelques environnements chauds algériens et essai de de production et de caractérisation de leurs protéases extracellulaires. [texte imprimé] / Mohamed Amine Gomri, Auteur ; Karima Kharroub, Directeur de thèse . - جامعة الإخوة منتوري قسنطينة, 2019 . - 308 f. ; 30 cm.
2 copies imprimées disponibles
Langues : Français (fre)
Catégories : Français - Anglais
Nutrition, Alimentation et Technologies Agro-AlimentairesTags : Biotechnologie:Sciences Alimentaires environnements chauds algériens diversité bactéries thermophiles protéases extracellulaires Algerian hot environments diversity bacteria thermophilic extracellular
proteases بينات ساخنة جزائرية تنوع-بكتيريا محبة للحرارة بروتياز خارج الخليةIndex. décimale : 640 Industrie Alimentaire Résumé :
Natural hot environments can represent an important source of microbial biodiversity and biomolecules with great added value. Among these biomolecules, extracellular hydrolases and in particular proteases are of great interest for the food industry because of their single reactional properties at high temperatures and their stability in various environmental conditions. The primary objective of this thesis is the isolation of thermophilic aerobic bacteria with extracellular proteolytic activities from 7 sites representing different Algerian hot environments: three geothermal sources, two Saharan soils, a sebkha and an oil field. On the
138 isolates selected on the basis of their macroscopic and microscopic morphological characters, 53 isolates able to degrade casein and/or gelatin on solid culture media were characterized by amplified ribosomal DNA restriction analysis. After the elimination of clones, 28 strains were identified by sequencing and analyzing their 16S rRNA genes. These strains belong to 5 genera of aerobic thermophilic endospore-forming bacteria: Anoxybacillus, Bacillus, Geobacillus, Brevibacillus and Thermoactinomyces. The physiological and biochemical characterization of these strains confirm the relationship with these genera. The genomes of two strains, Geobacillus Sah69 and Thermoactinomyces AS95, were then characterized. The production of putative extracellular proteases of industrial interest was revealed. In addition, the biodiversity of the geothermal sources of Debagh and Ouled Ali was studied by metagenomic analysis of the 16S rRNA hypervariable V4 region sequences of environmental DNA collected from sediment samples. The thermophilic aerobic bacterial communities dominate the two sites with a minor presence of the phylum of Firmicutes and the genera isolated by cultural methods. Lastly, the production of extracellular proteases was estimated quantitatively for the 28 selected strains. Study of production kinetics and effect of fermentation conditions on three selected strains, Geobacillus Sah69, Thermoactinomyces AS95 and Brevibacillus OA30, were then carried out. After the extraction of the supernatant, two proteases, metalloprotease 32- F38 and serine-protease 16-F39, were produced and purified from strain Brevibacillus OA30. These proteases were acid, thermoactive and had a great stability in presence of SDS, solvents and other chemical agents tested. Thus revealing a good potential for industrial application.Note de contenu :
Annexes.Diplôme : Doctorat en sciences En ligne : ../theses/agronomie/GOM7444.pdf Format de la ressource électronique : Permalink : https://bu.umc.edu.dz/md/index.php?lvl=notice_display&id=11222 Exemplaires (1)
Code-barres Cote Support Localisation Section Disponibilité GOM/7444 GOM/7444 Thèse Bibliothèque principale Thèses Disponible
Titre : Effet de la propolis sur les bactéries résistantes aux antibiotiques par inhibition des pompes à efflux. Type de document : texte imprimé Auteurs : Sagia Moussaoui, Auteur ; Mesbah Lahouel, Directeur de thèse Mention d'édition : 02-mai-19 Editeur : جامعة الإخوة منتوري قسنطينة Année de publication : 2019 Importance : 64 f. Format : 30 cm. Note générale : 1 copies imprimées disponibles
Langues : Français (fre) Catégories : Français - Anglais
BiologieTags : Sciences biologiques : Microbiologie Propolis Bactéries Pompes d’efflux inhibition CMIs Infection in vivo Bacteria efflux pumps MICs in vivo infection العكبر بكتيريا مضخات التدفق تثبيط التركيز الأدنى المثبط عدوى بكتيرية Index. décimale : 570 Sciences de la vie. Biologie Résumé : The resistance of bacteria to various anti-infectious chemotherapies has become a real public health problem. Bacteria ovoid antibiotics through the development of antimicrobiol resistance by draining grugs out the cells. Drug efflux is a key mechanism of resistance mechanism using pump systems located on the surface of bacterial membranes. For this, genetically modified bacteria carrying different types of efflux pumps were chosen as the study model on which Algerian propolis was tested. The tests in vitro performed on different bacterial strains have shown results comparable to those reported in the literature and confirm that Gram-positive bacteria are more sensitive to the effect of propolis than Gram-negative bacteria. In addition, the effectiveness of propolis also extends to resistant strains by efflux pump mechanisms The satisfactory results obtained encouraged us to carry out in vivo studies on wistar rats. The effects on a model of induced infection in rats were studied and evaluated by different laboratory parameters. Restoring the parameters tested in vivo after treatment of the infection with propolis, could confirm the interest of using it as a natural agent capable of countering the effects of oxidative stress linked to infections such as sepsis. As few information, on the clinical efficacy of Algerian propolis, is available, for this, a new step would be interesting to complete the research and thus develop the clinical investigations obtained which would make it possible to evaluate the beneficial effect of propolis in patients. Also the results obtained in this modest work could be used to justify the place that Algerian propolis may have for alternative therapies in the search. Note de contenu : Annexe. Diplôme : Doctorat en sciences En ligne : ../theses/biologie/MOU7694.pdf Format de la ressource électronique : Permalink : https://bu.umc.edu.dz/md/index.php?lvl=notice_display&id=11528 Effet de la propolis sur les bactéries résistantes aux antibiotiques par inhibition des pompes à efflux. [texte imprimé] / Sagia Moussaoui, Auteur ; Mesbah Lahouel, Directeur de thèse . - 02-mai-19 . - جامعة الإخوة منتوري قسنطينة, 2019 . - 64 f. ; 30 cm.
1 copies imprimées disponibles
Langues : Français (fre)
Catégories : Français - Anglais
BiologieTags : Sciences biologiques : Microbiologie Propolis Bactéries Pompes d’efflux inhibition CMIs Infection in vivo Bacteria efflux pumps MICs in vivo infection العكبر بكتيريا مضخات التدفق تثبيط التركيز الأدنى المثبط عدوى بكتيرية Index. décimale : 570 Sciences de la vie. Biologie Résumé : The resistance of bacteria to various anti-infectious chemotherapies has become a real public health problem. Bacteria ovoid antibiotics through the development of antimicrobiol resistance by draining grugs out the cells. Drug efflux is a key mechanism of resistance mechanism using pump systems located on the surface of bacterial membranes. For this, genetically modified bacteria carrying different types of efflux pumps were chosen as the study model on which Algerian propolis was tested. The tests in vitro performed on different bacterial strains have shown results comparable to those reported in the literature and confirm that Gram-positive bacteria are more sensitive to the effect of propolis than Gram-negative bacteria. In addition, the effectiveness of propolis also extends to resistant strains by efflux pump mechanisms The satisfactory results obtained encouraged us to carry out in vivo studies on wistar rats. The effects on a model of induced infection in rats were studied and evaluated by different laboratory parameters. Restoring the parameters tested in vivo after treatment of the infection with propolis, could confirm the interest of using it as a natural agent capable of countering the effects of oxidative stress linked to infections such as sepsis. As few information, on the clinical efficacy of Algerian propolis, is available, for this, a new step would be interesting to complete the research and thus develop the clinical investigations obtained which would make it possible to evaluate the beneficial effect of propolis in patients. Also the results obtained in this modest work could be used to justify the place that Algerian propolis may have for alternative therapies in the search. Note de contenu : Annexe. Diplôme : Doctorat en sciences En ligne : ../theses/biologie/MOU7694.pdf Format de la ressource électronique : Permalink : https://bu.umc.edu.dz/md/index.php?lvl=notice_display&id=11528 Exemplaires (1)
Code-barres Cote Support Localisation Section Disponibilité MOU/7694 MOU/7694 Thèse Bibliothèque principale Thèses Disponible
Titre : Utilisation de l’huile essentielle de Citrus limon comme agent conservateur et aromatique dans la crème fraîche Type de document : texte imprimé Auteurs : Farida Kehal, Auteur ; M Barkat, Directeur de thèse Editeur : constantine [Algérie] : Université Constantine 1 Année de publication : 2013 Importance : 104 f. Format : 30 cm. Note générale : 2 copies imprimées disponibles Langues : Français (fre) Catégories : Français - Anglais
Nutrition, Alimentation et Technologies Agro-AlimentairesTags : Crème fraîche levures bactéries huile essentielle écorce de citron analyse sensorielle Cream yeast bacteria essential oil lemon zest sensory analysis القشدة الطازجة الخمائر البيكتيريا الزيوت الأساسية قشور الليمون التحاليل الحسية Index. décimale : 640 Industrie Alimentaire Résumé :
This study was conducted in order to enhance the lemon peel (Citrus limon) by using their essential oil as a natural agent for preservation and aromatization in cream in order to diversify the types of
existing cream on the market.
This essential oil was extracted by hydroditillation, extraction yield was 0,89 ± 0,09%. The antioxidant activity of the extracted essential oil was studied by the DPPH° test, this free radical has been effectively reduced, compared to vitamin E. These results were confirmed by the test of β- carotene bleaching.
The study of antimicrobial activity of essential oil of C. limon showed that two tested bacteria are resistant against the effectiveness of the oil, resulting in very high MICs (4% and > 8%). Regarding yeast strains isolated and tested Debaryomyces sp. and Rhodotorula sp., they have some sensitivity
to the effect of essential oil, characterized by CMI respectively 0,25% and 0,5%. The other two strains Zygosaccharomyces sp1 and Zygosaccharomyces sp2, were resistant, their MICs are respectively in the order of 1% and > 4%.
The various tests on the formulation of the added essential oil of C. limon creams were tested by developing three fresh creams with concentrations of 0,125%, 0,25%, 0,5%. Characteristics are conforms to standard. The results of physicochemical and microbiological analyzes prepared fresh cream after opening the package, show that the presence of the essential oil at low concentrations does not limit microbial spoilage. The evaluation of the oxidative stability by Schaal test indicates that the fresh cream with essential oil of C. limon are more resistant than the control opposite the forced oxidation.
Sensory analysis show that the incorporation of essential oil in the cream, at concentrations of 0,125% and 0,25%, involves no significant difference (p > 0,05) in terms of flavoring, and make products which are classified in same order than the control. Only the rate of incorporation of the essential oil of 0,5% significantly downgraded the product compared to the control in the third row, which has led to changes in smell and flavor while the texture, color and taste are unchanged. The principal component analysis (PCA) showed a negative correlation (r = - 0,998) between the levels of incorporation of the essential oil and the aroma of raw milk, and a positive correlation (r = 0,956) with the color yellow.Diplôme : Magistère En ligne : ../theses/agronomie/KEH6360.pdf Format de la ressource électronique : Permalink : https://bu.umc.edu.dz/md/index.php?lvl=notice_display&id=6352 Utilisation de l’huile essentielle de Citrus limon comme agent conservateur et aromatique dans la crème fraîche [texte imprimé] / Farida Kehal, Auteur ; M Barkat, Directeur de thèse . - constantine [Algérie] : Université Constantine 1, 2013 . - 104 f. ; 30 cm.
2 copies imprimées disponibles
Langues : Français (fre)
Catégories : Français - Anglais
Nutrition, Alimentation et Technologies Agro-AlimentairesTags : Crème fraîche levures bactéries huile essentielle écorce de citron analyse sensorielle Cream yeast bacteria essential oil lemon zest sensory analysis القشدة الطازجة الخمائر البيكتيريا الزيوت الأساسية قشور الليمون التحاليل الحسية Index. décimale : 640 Industrie Alimentaire Résumé :
This study was conducted in order to enhance the lemon peel (Citrus limon) by using their essential oil as a natural agent for preservation and aromatization in cream in order to diversify the types of
existing cream on the market.
This essential oil was extracted by hydroditillation, extraction yield was 0,89 ± 0,09%. The antioxidant activity of the extracted essential oil was studied by the DPPH° test, this free radical has been effectively reduced, compared to vitamin E. These results were confirmed by the test of β- carotene bleaching.
The study of antimicrobial activity of essential oil of C. limon showed that two tested bacteria are resistant against the effectiveness of the oil, resulting in very high MICs (4% and > 8%). Regarding yeast strains isolated and tested Debaryomyces sp. and Rhodotorula sp., they have some sensitivity
to the effect of essential oil, characterized by CMI respectively 0,25% and 0,5%. The other two strains Zygosaccharomyces sp1 and Zygosaccharomyces sp2, were resistant, their MICs are respectively in the order of 1% and > 4%.
The various tests on the formulation of the added essential oil of C. limon creams were tested by developing three fresh creams with concentrations of 0,125%, 0,25%, 0,5%. Characteristics are conforms to standard. The results of physicochemical and microbiological analyzes prepared fresh cream after opening the package, show that the presence of the essential oil at low concentrations does not limit microbial spoilage. The evaluation of the oxidative stability by Schaal test indicates that the fresh cream with essential oil of C. limon are more resistant than the control opposite the forced oxidation.
Sensory analysis show that the incorporation of essential oil in the cream, at concentrations of 0,125% and 0,25%, involves no significant difference (p > 0,05) in terms of flavoring, and make products which are classified in same order than the control. Only the rate of incorporation of the essential oil of 0,5% significantly downgraded the product compared to the control in the third row, which has led to changes in smell and flavor while the texture, color and taste are unchanged. The principal component analysis (PCA) showed a negative correlation (r = - 0,998) between the levels of incorporation of the essential oil and the aroma of raw milk, and a positive correlation (r = 0,956) with the color yellow.Diplôme : Magistère En ligne : ../theses/agronomie/KEH6360.pdf Format de la ressource électronique : Permalink : https://bu.umc.edu.dz/md/index.php?lvl=notice_display&id=6352 Exemplaires (1)
Code-barres Cote Support Localisation Section Disponibilité KEH/6360 KEH/6360 Thèse Bibliothèque principale Thèses Disponible
Titre : Identification et étude moléculaire des bactéries et des archéo aérobies halophiles de la Sebkha Ezzemoul (Ain M' Lila) Type de document : texte imprimé Auteurs : Univ. de Constantine, Éditeur scientifique Année de publication : 2007 Importance : 193 f. Note générale : 01 Disponible à la salle de recherche 02 Disponibles au magazin de la B.U.C. 01 CD Langues : Français (fre) Catégories : Français - Anglais
BiologieTags : Phylogénie Sebkha Halophile extreme Archaea Bacteria Haloarchaea Séquen?age Hybridation ADN-ADN Environnements hypersalins Diversité microbienne Index. décimale : 570 Sciences de la vie. Biologie En ligne : ../theses/biologie/KHA4875.pdf Permalink : https://bu.umc.edu.dz/md/index.php?lvl=notice_display&id=1751 Identification et étude moléculaire des bactéries et des archéo aérobies halophiles de la Sebkha Ezzemoul (Ain M' Lila) [texte imprimé] / Univ. de Constantine, Éditeur scientifique . - 2007 . - 193 f.
01 Disponible à la salle de recherche 02 Disponibles au magazin de la B.U.C. 01 CD
Langues : Français (fre)
Catégories : Français - Anglais
BiologieTags : Phylogénie Sebkha Halophile extreme Archaea Bacteria Haloarchaea Séquen?age Hybridation ADN-ADN Environnements hypersalins Diversité microbienne Index. décimale : 570 Sciences de la vie. Biologie En ligne : ../theses/biologie/KHA4875.pdf Permalink : https://bu.umc.edu.dz/md/index.php?lvl=notice_display&id=1751 Exemplaires (1)
Code-barres Cote Support Localisation Section Disponibilité KHA/4875 KHA/4875 Thèse Bibliothèque principale Thèses Disponible Exemplaires (1)
Code-barres Cote Support Localisation Section Disponibilité BEN/6769 BEN/6769 Thèse Bibliothèque principale Thèses Disponible
