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Partager le résultat de cette recherche Interroger des sources externesResearch of antimicrobial potentialities of an endemic plant of the genus -Calycotome- / Radia Cherfia
Titre : Research of antimicrobial potentialities of an endemic plant of the genus -Calycotome- : phytochemical and microbiological study. Type de document : texte imprimé Auteurs : Radia Cherfia, Auteur ; Noreddine Kacem Chaouche, Directeur de thèse Mention d'édition : 06/ 01/ 2021 Editeur : جامعة الإخوة منتوري قسنطينة Année de publication : 2021 Importance : 168 f. Format : 30 cm. Note générale : 1 copies imprimées disponibles
Langues : Anglais (eng) Catégories : Français - Anglais
BiologieTags : Biologie et Ecologie Végétale: Biotechnologie végétale Calycotome spinosa (L.) Link LC-ESI-MS2 RMN 5-Hydroxyindoline activité antimicrobienne activité
anti-oxydante NMR antimicrobial activity antioxidant activity النشاط المضاد للمكريوبات النشاط المضاد للأكسدةIndex. décimale : 570 Sciences de la vie. Biologie Résumé :
The main objective of this research is the phytochemical characterization, the quantification of phenolic compounds, as well as the evaluation of the antioxidant and the antimicrobial potentials of certain extracts and fractions of leaves and flowers from the endemic plant Calycotome spinosa (L.) Link. Besides, the purification, the structural identification, and the investigation of the antioxidant and the antimicrobial capacities of isolated bioactive compounds have also been elucidated. As a result, many interesting chemical groups have been detected in this plant such as polyphenols, flavonoids, alkaloids, and sugars. The extracts (MeOH and aqueous) and the fractions (CHCl3, EtOAc, and n-BuOH) of the leaves and the flowers have high total polyphenols contents (TPC) compared to their flavonoids contents. Indeed, the EtOAc fraction of leaves exhibited the highest amount of TPC (107.75 ± 2.09 mg GAE / g DE), followed by the MeOH extract of the same part (98.72 ± 2.47 mg GAE / g DE), however, the MeOH extract of flowers had the lowest amount of these compounds (24.63 ± 0.35 mg GAE / g DE). Besides, it was shown that the same extract and the same fraction of leaves revealed the strongest free radical scavenging activity (DPPH; IC50 = 45.25 ± 1.8 and 41.04 ± 0.15 µg / mL, respectively), in addition to a remarkable reducing power (FRAP; EC50 = 763.73 ± 0.32 and 780.04 ± 1.36 µg / mL, consecutively), due to their, relatively, good content in phenolic compounds compared to the other tested extracts. The previous biological activity was accompanied by antimicrobial activity. Therefore, the diverse extracts displayed excellent antimicrobial activity, where the Gram+ test bacteria were more sensitive to these extracts than the Gram- ones. Thus, S. aureus was more sensitive to the MeOH extract of leaves with an inhibition zone (IZ) of 20.00 ± 0.28 mm, in contrast, bacterial strains ; B. subtilis and S. abony showed sensitivities to the MeOH extract and the EtOAc fraction of leaves with IZs of (16.00 ± 0.50 and 13 ± 0.65 mm) and (12 ± 0.29 and 16.00 ± 1.53 mm), respectively. the leaves’ MeOH extract was, furthermore, bactericidal against B. subtilis, S. aureus and S. abony with MICs ≤ 0.125 mg/ disc and a MBC of 1.00 mg/disc, whereas, Gram- bacteria; E. coli, P. aeruginosa, and K. pneumoniae were less susceptible. Moreover, two phytopathogenic fungal species of Alternaria were sensitive to all the tested extracts (MeOH and Aqueous) with variable inhibition percentages (IP %), however, no antifungal activity was observed against the yeast ‘Candida albicans’ and the other four tested fungal isolates; Penicillium sp.1, Penicillium sp.2, Aspergillus sp., and Rhizopus sp. From all these results, it was concluded that the leaves MeOH extract was the most efficient; therefore, it was selected for LC-ESI-MS2 analysis and for the separation of bioactive molecules. This separation using column chromatography(CC) led to a very interesting result; it is in fact the highlight, for the first time, of two new molecules from the plant, subject of study; 5-hydroxyindoline (4) and D-Pinitol (5), together with three well-known glucosidic flavonoids; Chrysin-7-O-(β-D-glucopyranoside) (1), chrysin-7-O-β-D-(6″-acetyl) glucopyranoside (2), and apigenin-7-O-β-D-glucopyranoside (3). The chemical structures of these isolated compounds have been elucidated based on spectroscopic analysis data and mass spectrometry; comprising a new approach 1D-NMR, 2D-NMR with LIT-ESI-MSn. The new compound, 5- Hydroxyindoline (4), demonstrated a very strong antibacterial potential against S. aureus (16 ± 0.5 mm), P. aeruginosa (9.83 ± 0.29 mm), and S. abony (8 ± 0.28 mm), as well it revealed a pertinent antioxidant capacity using four different methods (DPPH : IC50 < 10 μg / mL ; TAC = 985.54 ± 0.13 mg AAE / g DE ; FRAP : EC50 = 344.82 ± 0.02 μg / mL ; ABTS: IC50 = 7.8 ± 0.43 μg / mL), followed by the compound apigenin-7-O-β-D-glucopyranoside (3) which, also, exhibited remarkable antioxidant power, but lower than that of the new compound (4). These interesting results confirm that the aerial part of C. spinosa (L.) Link, in particular the leaves, usually used in traditional medicine in Algeria, can be considered as a source of substances with very effective antioxidant and antimicrobial activities.
Note de contenu :
Annexes.Diplôme : Doctorat en sciences En ligne : ../theses/biologie/CHE7744.pdf Format de la ressource électronique : Permalink : index.php?lvl=notice_display&id=11577 Research of antimicrobial potentialities of an endemic plant of the genus -Calycotome- : phytochemical and microbiological study. [texte imprimé] / Radia Cherfia, Auteur ; Noreddine Kacem Chaouche, Directeur de thèse . - 06/ 01/ 2021 . - جامعة الإخوة منتوري قسنطينة, 2021 . - 168 f. ; 30 cm.
1 copies imprimées disponibles
Langues : Anglais (eng)
Catégories : Français - Anglais
BiologieTags : Biologie et Ecologie Végétale: Biotechnologie végétale Calycotome spinosa (L.) Link LC-ESI-MS2 RMN 5-Hydroxyindoline activité antimicrobienne activité
anti-oxydante NMR antimicrobial activity antioxidant activity النشاط المضاد للمكريوبات النشاط المضاد للأكسدةIndex. décimale : 570 Sciences de la vie. Biologie Résumé :
The main objective of this research is the phytochemical characterization, the quantification of phenolic compounds, as well as the evaluation of the antioxidant and the antimicrobial potentials of certain extracts and fractions of leaves and flowers from the endemic plant Calycotome spinosa (L.) Link. Besides, the purification, the structural identification, and the investigation of the antioxidant and the antimicrobial capacities of isolated bioactive compounds have also been elucidated. As a result, many interesting chemical groups have been detected in this plant such as polyphenols, flavonoids, alkaloids, and sugars. The extracts (MeOH and aqueous) and the fractions (CHCl3, EtOAc, and n-BuOH) of the leaves and the flowers have high total polyphenols contents (TPC) compared to their flavonoids contents. Indeed, the EtOAc fraction of leaves exhibited the highest amount of TPC (107.75 ± 2.09 mg GAE / g DE), followed by the MeOH extract of the same part (98.72 ± 2.47 mg GAE / g DE), however, the MeOH extract of flowers had the lowest amount of these compounds (24.63 ± 0.35 mg GAE / g DE). Besides, it was shown that the same extract and the same fraction of leaves revealed the strongest free radical scavenging activity (DPPH; IC50 = 45.25 ± 1.8 and 41.04 ± 0.15 µg / mL, respectively), in addition to a remarkable reducing power (FRAP; EC50 = 763.73 ± 0.32 and 780.04 ± 1.36 µg / mL, consecutively), due to their, relatively, good content in phenolic compounds compared to the other tested extracts. The previous biological activity was accompanied by antimicrobial activity. Therefore, the diverse extracts displayed excellent antimicrobial activity, where the Gram+ test bacteria were more sensitive to these extracts than the Gram- ones. Thus, S. aureus was more sensitive to the MeOH extract of leaves with an inhibition zone (IZ) of 20.00 ± 0.28 mm, in contrast, bacterial strains ; B. subtilis and S. abony showed sensitivities to the MeOH extract and the EtOAc fraction of leaves with IZs of (16.00 ± 0.50 and 13 ± 0.65 mm) and (12 ± 0.29 and 16.00 ± 1.53 mm), respectively. the leaves’ MeOH extract was, furthermore, bactericidal against B. subtilis, S. aureus and S. abony with MICs ≤ 0.125 mg/ disc and a MBC of 1.00 mg/disc, whereas, Gram- bacteria; E. coli, P. aeruginosa, and K. pneumoniae were less susceptible. Moreover, two phytopathogenic fungal species of Alternaria were sensitive to all the tested extracts (MeOH and Aqueous) with variable inhibition percentages (IP %), however, no antifungal activity was observed against the yeast ‘Candida albicans’ and the other four tested fungal isolates; Penicillium sp.1, Penicillium sp.2, Aspergillus sp., and Rhizopus sp. From all these results, it was concluded that the leaves MeOH extract was the most efficient; therefore, it was selected for LC-ESI-MS2 analysis and for the separation of bioactive molecules. This separation using column chromatography(CC) led to a very interesting result; it is in fact the highlight, for the first time, of two new molecules from the plant, subject of study; 5-hydroxyindoline (4) and D-Pinitol (5), together with three well-known glucosidic flavonoids; Chrysin-7-O-(β-D-glucopyranoside) (1), chrysin-7-O-β-D-(6″-acetyl) glucopyranoside (2), and apigenin-7-O-β-D-glucopyranoside (3). The chemical structures of these isolated compounds have been elucidated based on spectroscopic analysis data and mass spectrometry; comprising a new approach 1D-NMR, 2D-NMR with LIT-ESI-MSn. The new compound, 5- Hydroxyindoline (4), demonstrated a very strong antibacterial potential against S. aureus (16 ± 0.5 mm), P. aeruginosa (9.83 ± 0.29 mm), and S. abony (8 ± 0.28 mm), as well it revealed a pertinent antioxidant capacity using four different methods (DPPH : IC50 < 10 μg / mL ; TAC = 985.54 ± 0.13 mg AAE / g DE ; FRAP : EC50 = 344.82 ± 0.02 μg / mL ; ABTS: IC50 = 7.8 ± 0.43 μg / mL), followed by the compound apigenin-7-O-β-D-glucopyranoside (3) which, also, exhibited remarkable antioxidant power, but lower than that of the new compound (4). These interesting results confirm that the aerial part of C. spinosa (L.) Link, in particular the leaves, usually used in traditional medicine in Algeria, can be considered as a source of substances with very effective antioxidant and antimicrobial activities.
Note de contenu :
Annexes.Diplôme : Doctorat en sciences En ligne : ../theses/biologie/CHE7744.pdf Format de la ressource électronique : Permalink : index.php?lvl=notice_display&id=11577 Exemplaires (1)
Code-barres Cote Support Localisation Section Disponibilité CHE/7744 CHE/7744 Thèse Bibliothèque principale Thèses Disponible
Titre : Etude phytochimique et pharmacologique de Crataegus oxyacantha L. (Rosaceae) et Cytisus triflorus L’Her. (Fabaceae). Type de document : texte imprimé Auteurs : Wassila Benabderrahmane, Auteur ; Ouahiba Benaissa, Directeur de thèse Editeur : جامعة الإخوة منتوري قسنطينة Année de publication : 2019 Importance : 234 f. Format : 30 cm. Note générale : 2 copies imprimées disponibles
Langues : Français (fre) Catégories : Français - Anglais
ChimieTags : Chimie organique: phytochimie Rosaceae Fabaceae Crataegus oxyacantha Cytisus triflorus Flavonoïdes composés phénoliques Activité antioxydante Activité antimicrobienne RMN 1D et 2D HPLC-DAD Flavonoids Phenolic compounds Antioxidant activity Antimicrobial activity 1D and 2D NMR HPLCDAD فلافونويدات مركبات فينولية النشاط المضاد للأكسدة النشاط المصاد للميكروبات Index. décimale : 540 Chimie et sciences connexes Résumé :
The work presented in this thesis contributes to the valorization of both Algerian medicinal plants (Crataegus oxyacantha L. (Rosaceae) and Cytisus triflorus L'Her. (Fabaceae) by characterizing them by a phytochemical study, an evaluation of the antioxidant and antimicrobial activities, and a structural identification of certain phenolic compounds. Thus, in order to obtain an extract enriched in metabolites of interest, flavonoids, we opted for two extraction methods, a liquid solid extraction using different solvents of increasing polarity (CHCl3, EtOAc and n-Butanol) and a second extraction using the Matrix solid phase dispersion (MSPD) method, using different solvents of increasing polarity (100% H2O, 1:1 H2O / EtOH and 100% EtOH).
This study allowed the isolation 21 compounds and structural elucidation of 16 compounds.
Of these 16 compounds, 3 acids and 7 flavonoids: (3 flavonols including 1 glucosyl, 1 glucosyl flavanone, 1 Flavanol and 2 flavones) were isolated from C. oxyacantha L. From the EtOAc extract the aerial parts (Flowers + Leaves) of the species Cytisus triflorus L'Her., 6 secondary metabolites were identified (flavonoids). Among these compounds, 3 flavones: (Chrysin, Prunetin) and 3 glucosyl flavonoids (2 Chrysine and Isoquercitrin). Of these isolated compounds, 3 new in the species. These major active ingredients possess various biological activities and play an important and acknowledged role in maintaining good health. The structures of the isolated compounds were established by HPLC-DAD chromatogram analysis, UV-vis spectra and high resolution electrospray mass spectra (HRESI-MS), by extensive use and interpretation of NMR experiments spectra : 1D NMR (1H, 13C and DEPT) and 2D NMR (COSY, HSQC and HMBC) and by comparison with the literature data. The in vitro evaluation antioxidant activity of the various extracts and of three isolated products of C. oxyacantha, and the AcOEt extract and three products isolated from C. triflorus was performed by the radical scavenging method (DPPH *). The extracts of two plants have interesting antioxidant activities, dependent on the content of total polyphenols and flavonoids. The various extracts studied were also revealed a high antibacterial activity towards S. aureus. Similarly, a tendency shown indicating that the richest extracts of flavonoids and polyphenols exhibit the higher antibacterial activities.Note de contenu :
Annexe.Diplôme : Doctorat en sciences En ligne : ../theses/chimie/BEN7472.pdf Format de la ressource électronique : Permalink : index.php?lvl=notice_display&id=11304 Etude phytochimique et pharmacologique de Crataegus oxyacantha L. (Rosaceae) et Cytisus triflorus L’Her. (Fabaceae). [texte imprimé] / Wassila Benabderrahmane, Auteur ; Ouahiba Benaissa, Directeur de thèse . - جامعة الإخوة منتوري قسنطينة, 2019 . - 234 f. ; 30 cm.
2 copies imprimées disponibles
Langues : Français (fre)
Catégories : Français - Anglais
ChimieTags : Chimie organique: phytochimie Rosaceae Fabaceae Crataegus oxyacantha Cytisus triflorus Flavonoïdes composés phénoliques Activité antioxydante Activité antimicrobienne RMN 1D et 2D HPLC-DAD Flavonoids Phenolic compounds Antioxidant activity Antimicrobial activity 1D and 2D NMR HPLCDAD فلافونويدات مركبات فينولية النشاط المضاد للأكسدة النشاط المصاد للميكروبات Index. décimale : 540 Chimie et sciences connexes Résumé :
The work presented in this thesis contributes to the valorization of both Algerian medicinal plants (Crataegus oxyacantha L. (Rosaceae) and Cytisus triflorus L'Her. (Fabaceae) by characterizing them by a phytochemical study, an evaluation of the antioxidant and antimicrobial activities, and a structural identification of certain phenolic compounds. Thus, in order to obtain an extract enriched in metabolites of interest, flavonoids, we opted for two extraction methods, a liquid solid extraction using different solvents of increasing polarity (CHCl3, EtOAc and n-Butanol) and a second extraction using the Matrix solid phase dispersion (MSPD) method, using different solvents of increasing polarity (100% H2O, 1:1 H2O / EtOH and 100% EtOH).
This study allowed the isolation 21 compounds and structural elucidation of 16 compounds.
Of these 16 compounds, 3 acids and 7 flavonoids: (3 flavonols including 1 glucosyl, 1 glucosyl flavanone, 1 Flavanol and 2 flavones) were isolated from C. oxyacantha L. From the EtOAc extract the aerial parts (Flowers + Leaves) of the species Cytisus triflorus L'Her., 6 secondary metabolites were identified (flavonoids). Among these compounds, 3 flavones: (Chrysin, Prunetin) and 3 glucosyl flavonoids (2 Chrysine and Isoquercitrin). Of these isolated compounds, 3 new in the species. These major active ingredients possess various biological activities and play an important and acknowledged role in maintaining good health. The structures of the isolated compounds were established by HPLC-DAD chromatogram analysis, UV-vis spectra and high resolution electrospray mass spectra (HRESI-MS), by extensive use and interpretation of NMR experiments spectra : 1D NMR (1H, 13C and DEPT) and 2D NMR (COSY, HSQC and HMBC) and by comparison with the literature data. The in vitro evaluation antioxidant activity of the various extracts and of three isolated products of C. oxyacantha, and the AcOEt extract and three products isolated from C. triflorus was performed by the radical scavenging method (DPPH *). The extracts of two plants have interesting antioxidant activities, dependent on the content of total polyphenols and flavonoids. The various extracts studied were also revealed a high antibacterial activity towards S. aureus. Similarly, a tendency shown indicating that the richest extracts of flavonoids and polyphenols exhibit the higher antibacterial activities.Note de contenu :
Annexe.Diplôme : Doctorat en sciences En ligne : ../theses/chimie/BEN7472.pdf Format de la ressource électronique : Permalink : index.php?lvl=notice_display&id=11304 Exemplaires (1)
Code-barres Cote Support Localisation Section Disponibilité BEN/7472 BEN/7472 Thèse Bibliothèque principale Thèses Disponible
Titre : Etude phytochimique et valorisation biologique de deux plantes, Genista microcephala Coss & Dur (Fabaceae) et Jurinea humilis DC (Asteraseae). Type de document : texte imprimé Auteurs : Djamila Maanani, Auteur ; Salah Rhouati, Directeur de thèse ; Amar Zellagui, Directeur de thèse Editeur : جامعة الإخوة منتوري قسنطينة Année de publication : 2018 Importance : 177 f. Format : 30 cm. Note générale : Doctorat 3éme CYCLE LMD.
2 copies imprimées disponiblesLangues : Français (fre) Catégories : Français - Anglais
ChimieTags : Chimie Organique:Phytochimie Activité antimicrobienne activité antioxydant acides gras Genista microcephala Jurinéa humilis composés phénoliques Antimicrobial activity antioxidant activity fatty acids Jurinea humilis phenolic compounds النشاط المضاد للبكتيريا النشاط المضاد للأكسدة الأحماض الدهنية المركبات الفينولي Index. décimale : 540 Chimie et sciences connexes Résumé :
This work is concerning the phytochemical study of two Algerian plants, the first belonging to the Fabaceae family (Genista microcephala coss & dur) and Asteraceae family (Jurinea humilis DC). The phytochemical study of the two Algerian medicinal plants allowed the identification of five isoflavonoids from ethyl acetate and butanol extracts of G. microcephala and three flavonoids from butanol extract of J.humilis, isolated for the first time in both plants, The structurs of compounds were elucidated by various spectroscopic methods spectral: 1D and 2D NMR (1H, 13C, DEPT, HMBC and HMQC), UV, mass spectrometry (MS) and by comparison with lettirature valrieus. The biological study carried out to determine the phenolic content and to evaluate the antioxidant and antimicrobial activities of Genista microcephala. Antioxidant activity was evaluated by various in vitro tests, including Ferric Ion Reducing Activity (FRAP), Cupric Ion Reducing Antioxidant Capacity (CUPRAC), and total antioxidant capacities (TAC). The antimicrobial activity of ethyl acetate and butanolic extracts of G. microcephala in addition of fatty acids content of different parts of plant was evaluated against human pathogenic bacteria, fish bacteria and yeast. The used methods were agar diffusion method and the determination of minimal bactericidal and fungicidal concentrations (MBC and MFC). Ethyl acetate extract was the most active regarding antioxidant and antimicrobienne assays. The tested activity seems to be due to the high content of this extract on isoflavonoids.Note de contenu :
annexeDiplôme : Doctorat En ligne : ../theses/chimie/MAA7436.pdf Format de la ressource électronique : Permalink : index.php?lvl=notice_display&id=11175 Etude phytochimique et valorisation biologique de deux plantes, Genista microcephala Coss & Dur (Fabaceae) et Jurinea humilis DC (Asteraseae). [texte imprimé] / Djamila Maanani, Auteur ; Salah Rhouati, Directeur de thèse ; Amar Zellagui, Directeur de thèse . - جامعة الإخوة منتوري قسنطينة, 2018 . - 177 f. ; 30 cm.
Doctorat 3éme CYCLE LMD.
2 copies imprimées disponibles
Langues : Français (fre)
Catégories : Français - Anglais
ChimieTags : Chimie Organique:Phytochimie Activité antimicrobienne activité antioxydant acides gras Genista microcephala Jurinéa humilis composés phénoliques Antimicrobial activity antioxidant activity fatty acids Jurinea humilis phenolic compounds النشاط المضاد للبكتيريا النشاط المضاد للأكسدة الأحماض الدهنية المركبات الفينولي Index. décimale : 540 Chimie et sciences connexes Résumé :
This work is concerning the phytochemical study of two Algerian plants, the first belonging to the Fabaceae family (Genista microcephala coss & dur) and Asteraceae family (Jurinea humilis DC). The phytochemical study of the two Algerian medicinal plants allowed the identification of five isoflavonoids from ethyl acetate and butanol extracts of G. microcephala and three flavonoids from butanol extract of J.humilis, isolated for the first time in both plants, The structurs of compounds were elucidated by various spectroscopic methods spectral: 1D and 2D NMR (1H, 13C, DEPT, HMBC and HMQC), UV, mass spectrometry (MS) and by comparison with lettirature valrieus. The biological study carried out to determine the phenolic content and to evaluate the antioxidant and antimicrobial activities of Genista microcephala. Antioxidant activity was evaluated by various in vitro tests, including Ferric Ion Reducing Activity (FRAP), Cupric Ion Reducing Antioxidant Capacity (CUPRAC), and total antioxidant capacities (TAC). The antimicrobial activity of ethyl acetate and butanolic extracts of G. microcephala in addition of fatty acids content of different parts of plant was evaluated against human pathogenic bacteria, fish bacteria and yeast. The used methods were agar diffusion method and the determination of minimal bactericidal and fungicidal concentrations (MBC and MFC). Ethyl acetate extract was the most active regarding antioxidant and antimicrobienne assays. The tested activity seems to be due to the high content of this extract on isoflavonoids.Note de contenu :
annexeDiplôme : Doctorat En ligne : ../theses/chimie/MAA7436.pdf Format de la ressource électronique : Permalink : index.php?lvl=notice_display&id=11175 Exemplaires (1)
Code-barres Cote Support Localisation Section Disponibilité MAA/7436 MAA/7436 Thèse Bibliothèque principale Thèses Disponible
Titre : Evaluation de l'activité antioxydante et antimicrobienne de l'homogénat du gastéropode : Helix aspersa Type de document : texte imprimé Auteurs : Rima Hammoud, Auteur ; D. Naimi, Directeur de thèse Editeur : constantine [Algérie] : Université Constantine 1 Année de publication : 2013 Importance : 87 f. Format : 30 cm. Note générale : 2 copies imprimées disponibles Langues : Français (fre) Catégories : Français - Anglais
BiologieTags : L-Méthionine hyperhomocystéinémie Helix aspersa extraits organiques bruts activité
antioxydante activité antimicrobienne L-Methionine hyerhomocysteinemia crude organic extracts antioxidant activity antimicrobial activity المستخلصات العضویة الخام النشاط المضاد للأكسدة میتیونین ایبار أوموسیستاینامیا L
النشاط المضاد للكائنات الحیة المجھریة.Index. décimale : 570 Sciences de la vie. Biologie Résumé : In this study, we took an interest in the evaluation of the antioxidant and antimicrobial effects of Helix aspersa snail homogenate. In order to reach our goals, three principal stages were undertaken:
* Submission of rats at a high L-Methionine diet (400mg/kg of the weight of the rat/day) in order to induce an oxidative stress.
* Treatment of rats by Helix aspersa snail homogenate (100mg/kg of the weight of the rat/day) associated with a high dose of the L-Methionine.
* Evaluation of the antimicrobial activity of Helix aspersa snail crude organic extracts against three bacterial strains (Escherichia coli ATCC 25922, Klebsiella pneumoniae ATCC 700603,Pseudomonas aeruginosa 13), twoo fungal strains (Aspergillus fumigatus CIP 1082.74,Trichophytum rubrum CIP 2043.92) and one strain of yeast (Candida albicans UMIP 88465) by the use of paper disk assay method.
The results of MDA and total protein mixtures showed that:
* On one hand, an increase of hepatic MD (p≤0,001) and plasmatic total protein levels (p≤0,0001) on rats that receiving a high dose of the L-Methionine, explaining thus theproceedings of lipid peroxidation phenomenons and the cellular proteins oxidation.
* On the other hand, a decrease of the levels of plasmatic (p≤0,0001) and hepatic MDA (p≤0,001), and plasmatic total proteins (p≤0,0001) following treatment of hyperhomocysteinemic rats with the snails homogenate. This allowed us to conclude that the Helix aspersa snail homogenate has antioxidant properties.
The microbiological test revealed an antibacterial activity of snails crude organic extracts prepared with distilled water.
Escherichia coli ATCC 25922 was revealed as the most sensitive of the three test-bacteria.
No anti fungal activity was determined.
The preliminary characterization of antibacterial molecules of Helix aspersa snail crude organic extracts allowed us to conclude that they can probably have protein linked and/or free nature.Diplôme : Magistère En ligne : ../theses/biologie/HAM6355.pdf Format de la ressource électronique : Permalink : index.php?lvl=notice_display&id=6321 Evaluation de l'activité antioxydante et antimicrobienne de l'homogénat du gastéropode : Helix aspersa [texte imprimé] / Rima Hammoud, Auteur ; D. Naimi, Directeur de thèse . - constantine [Algérie] : Université Constantine 1, 2013 . - 87 f. ; 30 cm.
2 copies imprimées disponibles
Langues : Français (fre)
Catégories : Français - Anglais
BiologieTags : L-Méthionine hyperhomocystéinémie Helix aspersa extraits organiques bruts activité
antioxydante activité antimicrobienne L-Methionine hyerhomocysteinemia crude organic extracts antioxidant activity antimicrobial activity المستخلصات العضویة الخام النشاط المضاد للأكسدة میتیونین ایبار أوموسیستاینامیا L
النشاط المضاد للكائنات الحیة المجھریة.Index. décimale : 570 Sciences de la vie. Biologie Résumé : In this study, we took an interest in the evaluation of the antioxidant and antimicrobial effects of Helix aspersa snail homogenate. In order to reach our goals, three principal stages were undertaken:
* Submission of rats at a high L-Methionine diet (400mg/kg of the weight of the rat/day) in order to induce an oxidative stress.
* Treatment of rats by Helix aspersa snail homogenate (100mg/kg of the weight of the rat/day) associated with a high dose of the L-Methionine.
* Evaluation of the antimicrobial activity of Helix aspersa snail crude organic extracts against three bacterial strains (Escherichia coli ATCC 25922, Klebsiella pneumoniae ATCC 700603,Pseudomonas aeruginosa 13), twoo fungal strains (Aspergillus fumigatus CIP 1082.74,Trichophytum rubrum CIP 2043.92) and one strain of yeast (Candida albicans UMIP 88465) by the use of paper disk assay method.
The results of MDA and total protein mixtures showed that:
* On one hand, an increase of hepatic MD (p≤0,001) and plasmatic total protein levels (p≤0,0001) on rats that receiving a high dose of the L-Methionine, explaining thus theproceedings of lipid peroxidation phenomenons and the cellular proteins oxidation.
* On the other hand, a decrease of the levels of plasmatic (p≤0,0001) and hepatic MDA (p≤0,001), and plasmatic total proteins (p≤0,0001) following treatment of hyperhomocysteinemic rats with the snails homogenate. This allowed us to conclude that the Helix aspersa snail homogenate has antioxidant properties.
The microbiological test revealed an antibacterial activity of snails crude organic extracts prepared with distilled water.
Escherichia coli ATCC 25922 was revealed as the most sensitive of the three test-bacteria.
No anti fungal activity was determined.
The preliminary characterization of antibacterial molecules of Helix aspersa snail crude organic extracts allowed us to conclude that they can probably have protein linked and/or free nature.Diplôme : Magistère En ligne : ../theses/biologie/HAM6355.pdf Format de la ressource électronique : Permalink : index.php?lvl=notice_display&id=6321 Exemplaires (1)
Code-barres Cote Support Localisation Section Disponibilité HAM/6355 HAM/6355 Thèse Bibliothèque principale Thèses Disponible
Titre : Exploitation et caractérisation des substances bioactives sécrétées par une souche d’Aspergillus sp. Type de document : texte imprimé Auteurs : Afaf Sakhri, Auteur ; Noreddine Kacem Chaouche, Directeur de thèse Mention d'édition : 07-juil-20 Editeur : جامعة الإخوة منتوري قسنطينة Année de publication : 2020 Importance : 110 f. Format : 30 cm. Note générale : 1 copies imprimées disponibles
Langues : Français (fre) Catégories : Français - Anglais
BiologieTags : Microbiologie: Biochimie microbienne Aspergillus creber Activité antimicrobienne substances bioactives activité antioxydante UHPLC-HRMS/MS Versicolores Antimicrobial activity bioactive substances antioxidant activity Aspergillusالنشاط المضاد للميكروبات المواد النشطة بيولوجيا النشاط المضاد للأكسدة
Versicolores UHPLC-HRMS/ MIndex. décimale : 570 Sciences de la vie. Biologie Résumé :
The present work aims to evaluate some biological activities of a strain of spergillus and to identify its bioactive molecules potentially interesting. The exploration of corn samples destined to poultry feed allowed the isolation of 155 fungal strains belonging to the genus Aspergillus. One strain was selected, in vitro, by agar diffusion method, for its strong antimicrobial activity. Morphological and molecular identification of the selected isolate showed that it is Aspergillus creber. Preliminary test of the production of bioactive substances on different submerged culture media revealed that the Czapeck Yeast Broth (CYB) medium is the most favourable medium for this production. After the production of these molecules, the extraction was carried out using ethyl acetate. Study of the antimicrobial activity of ethyl acetate extract has shown that A. creber has a high activity against Candida albicans, with an MIC value of 0.325 mg / mL, followed by the multiresistant Gram-positive bacteria Staphylococcus aureus producing β-lactamase and Staphtloccoccus epidermidis resistant to methicillin with an MIC value of 0.625 mg / mL. Gram-negative bacteria were found to be more resistant with an MIC value ranging from 2.5 to 5 mg / mL. In addition, A. creber extract showed a significant capacity to trap free radicals DPPH • and ABTS • + with IC50 values of 108.76 ± 1.02 μg / mL and 90.82 ± 0.61 μg / mL respectively. A. creber extract showed also a powerful reducing power. The determination of total polyphenols by the FolinCiocalteu method showed a significant content of polyphenolic compounds estimated at 85.76 mg EGA / g. It is important to emphasize, that this work is the first one to have shown the ability of A. creber to produce molecules with antimicrobial and antioxidant activities. The chromatographic analysis of A. creber extract by ultra high performance liquid chromatography coupled with high resolution mass spectrometry (UHPLC-HRMS / MS) allowed the identification of five known molecules as asperlactone, emodin, sterigmatocystin, deoxybrevianamide E and norsolorinic acid, in addition to five other molecules which seem to be close to the known molecules but with some differences demonstrated in this work. Thus, it is probably that are novel molecules. To our knowledge, the demonstration of the production of asperlactone by A. creber, is a first, no study has mentioned the ability of the species of Aspergillus section Versicolores, in particular A. creber, to produce this compound. These results are promising and are considered to be a remarkable advance in the research of natural bioactive substances.
Note de contenu :
Annexes.
Diplôme : Doctorat en sciences En ligne : ../theses/biologie/SAK7648.pdf Format de la ressource électronique : Permalink : index.php?lvl=notice_display&id=11482 Exploitation et caractérisation des substances bioactives sécrétées par une souche d’Aspergillus sp. [texte imprimé] / Afaf Sakhri, Auteur ; Noreddine Kacem Chaouche, Directeur de thèse . - 07-juil-20 . - جامعة الإخوة منتوري قسنطينة, 2020 . - 110 f. ; 30 cm.
1 copies imprimées disponibles
Langues : Français (fre)
Catégories : Français - Anglais
BiologieTags : Microbiologie: Biochimie microbienne Aspergillus creber Activité antimicrobienne substances bioactives activité antioxydante UHPLC-HRMS/MS Versicolores Antimicrobial activity bioactive substances antioxidant activity Aspergillusالنشاط المضاد للميكروبات المواد النشطة بيولوجيا النشاط المضاد للأكسدة
Versicolores UHPLC-HRMS/ MIndex. décimale : 570 Sciences de la vie. Biologie Résumé :
The present work aims to evaluate some biological activities of a strain of spergillus and to identify its bioactive molecules potentially interesting. The exploration of corn samples destined to poultry feed allowed the isolation of 155 fungal strains belonging to the genus Aspergillus. One strain was selected, in vitro, by agar diffusion method, for its strong antimicrobial activity. Morphological and molecular identification of the selected isolate showed that it is Aspergillus creber. Preliminary test of the production of bioactive substances on different submerged culture media revealed that the Czapeck Yeast Broth (CYB) medium is the most favourable medium for this production. After the production of these molecules, the extraction was carried out using ethyl acetate. Study of the antimicrobial activity of ethyl acetate extract has shown that A. creber has a high activity against Candida albicans, with an MIC value of 0.325 mg / mL, followed by the multiresistant Gram-positive bacteria Staphylococcus aureus producing β-lactamase and Staphtloccoccus epidermidis resistant to methicillin with an MIC value of 0.625 mg / mL. Gram-negative bacteria were found to be more resistant with an MIC value ranging from 2.5 to 5 mg / mL. In addition, A. creber extract showed a significant capacity to trap free radicals DPPH • and ABTS • + with IC50 values of 108.76 ± 1.02 μg / mL and 90.82 ± 0.61 μg / mL respectively. A. creber extract showed also a powerful reducing power. The determination of total polyphenols by the FolinCiocalteu method showed a significant content of polyphenolic compounds estimated at 85.76 mg EGA / g. It is important to emphasize, that this work is the first one to have shown the ability of A. creber to produce molecules with antimicrobial and antioxidant activities. The chromatographic analysis of A. creber extract by ultra high performance liquid chromatography coupled with high resolution mass spectrometry (UHPLC-HRMS / MS) allowed the identification of five known molecules as asperlactone, emodin, sterigmatocystin, deoxybrevianamide E and norsolorinic acid, in addition to five other molecules which seem to be close to the known molecules but with some differences demonstrated in this work. Thus, it is probably that are novel molecules. To our knowledge, the demonstration of the production of asperlactone by A. creber, is a first, no study has mentioned the ability of the species of Aspergillus section Versicolores, in particular A. creber, to produce this compound. These results are promising and are considered to be a remarkable advance in the research of natural bioactive substances.
Note de contenu :
Annexes.
Diplôme : Doctorat en sciences En ligne : ../theses/biologie/SAK7648.pdf Format de la ressource électronique : Permalink : index.php?lvl=notice_display&id=11482 Exemplaires (1)
Code-barres Cote Support Localisation Section Disponibilité SAK/7648 SAK/7648 Thèse Bibliothèque principale Thèses Disponible
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