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Partager le résultat de cette recherche Interroger des sources externesEssais d'optimisation des conditions de cuisson et d'extraction des polyphénols de six légumes et évaluation des activités / Imène Laib
Titre : Essais d'optimisation des conditions de cuisson et d'extraction des polyphénols de six légumes et évaluation des activités : antioxydante et anticholinestérase. Type de document : texte imprimé Auteurs : Imène Laib, Auteur ; Malika Barkat, Directeur de thèse Editeur : جامعة الإخوة منتوري قسنطينة Année de publication : 2018 Importance : 287 f. Format : 30 cm. Note générale : 2 copies imprimées disponibles
Langues : Français (fre) Tags : Optimisation légume cuisson polyphénols totaux flavonoïdes activité antioxydante activité anticholinestérase Optimization vegetable cooking total polyphenolic flavonoids antioxidant activity anticholinesterase activity ?????? ????? ??????????? ????? ??????????? ?????? ?????? ??????? ???? ??????
????????????Index. décimale : 640 Industrie Alimentaire Résumé : This study focuses on the optimization of the cooking conditions and the extraction of polyphenols from six vegetables (potato, onion, spinach, aubergine carrot and pepper) and the study of the impact of the cooking method (boiling, steaming and microwaving) on these compounds and their biological activities (antioxidant activity and anticholinesterase activity).
To evaluate the quantity of phenolic compounds extracted from raw and cooked vegetables, a experiment design was realized. The factors chosen are (Temperature, time, power) for cooking and (solvent concentration, maceration time, ultrasonication and grinding) for polyphenol extraction . The study was initiated by Plackett-Burmann design to perform the screening of factors and to select the most influential on the Y response (total phenolic) and an optimization by exploiting central composite design. Determination of total polyphenols, flavonoids and LC-MS / MS analysis were performed to monitor the variation of phenolic compounds after cooking. In addition, in this work, we anlyzed antioxidant and anticholinesterase properties of the phenolic compounds of the six raw and cooked vegetables.
The results obtained for the six vegetables are different, boiling in water and steam cooking methods have reduced the levels of total polyphenols and flavonoids of the six vegetables. While microwave cooking had different effects on the six vegetables, it had a negative effect on the total polyphenol and flavonoid levels of the potato, spinach, carrot and pepper.
However, a positive effect was recorded on the total polyphenols and flavonoids of eggplant. Retention of these compounds has been observed in onions cooked by microwave. The impact of cooking on antioxidant activity varies from one vegetable to another. Cooking caused a decrease in the antioxidant activity of potatoes, onions, carrots, peppers and steamed spinach.
A positive effect of cooking was recorded on the antioxidant potential of spinach (cooked in water and by microwave) and eggplant. All three cooking methods showed negative effects on the anticholinesterase activity of potato, spinach and pepper. However, an increase in this activity was recorded for onion, eggplant and carrot. Cooking in water proved to be the worst method for preserving the polyphenols from cooked vegetables and their activities (antioxidant activity and anticholinesterase). The losses of polyphenols are due to their increased solubility in water. However, microwave cooking is suggested as the best method to preserve the polyphenol levels, the antioxidant and anticholinesterase activities of the studied vegetables.
Diplôme : Doctorat en sciences En ligne : ../theses/agronomie/LAI7279.pdf Format de la ressource électronique : Permalink : https://bu.umc.edu.dz/md/index.php?lvl=notice_display&id=10894 Essais d'optimisation des conditions de cuisson et d'extraction des polyphénols de six légumes et évaluation des activités : antioxydante et anticholinestérase. [texte imprimé] / Imène Laib, Auteur ; Malika Barkat, Directeur de thèse . - [S.l.] : جامعة الإخوة منتوري قسنطينة, 2018 . - 287 f. ; 30 cm.
2 copies imprimées disponibles
Langues : Français (fre)
Tags : Optimisation légume cuisson polyphénols totaux flavonoïdes activité antioxydante activité anticholinestérase Optimization vegetable cooking total polyphenolic flavonoids antioxidant activity anticholinesterase activity ?????? ????? ??????????? ????? ??????????? ?????? ?????? ??????? ???? ??????
????????????Index. décimale : 640 Industrie Alimentaire Résumé : This study focuses on the optimization of the cooking conditions and the extraction of polyphenols from six vegetables (potato, onion, spinach, aubergine carrot and pepper) and the study of the impact of the cooking method (boiling, steaming and microwaving) on these compounds and their biological activities (antioxidant activity and anticholinesterase activity).
To evaluate the quantity of phenolic compounds extracted from raw and cooked vegetables, a experiment design was realized. The factors chosen are (Temperature, time, power) for cooking and (solvent concentration, maceration time, ultrasonication and grinding) for polyphenol extraction . The study was initiated by Plackett-Burmann design to perform the screening of factors and to select the most influential on the Y response (total phenolic) and an optimization by exploiting central composite design. Determination of total polyphenols, flavonoids and LC-MS / MS analysis were performed to monitor the variation of phenolic compounds after cooking. In addition, in this work, we anlyzed antioxidant and anticholinesterase properties of the phenolic compounds of the six raw and cooked vegetables.
The results obtained for the six vegetables are different, boiling in water and steam cooking methods have reduced the levels of total polyphenols and flavonoids of the six vegetables. While microwave cooking had different effects on the six vegetables, it had a negative effect on the total polyphenol and flavonoid levels of the potato, spinach, carrot and pepper.
However, a positive effect was recorded on the total polyphenols and flavonoids of eggplant. Retention of these compounds has been observed in onions cooked by microwave. The impact of cooking on antioxidant activity varies from one vegetable to another. Cooking caused a decrease in the antioxidant activity of potatoes, onions, carrots, peppers and steamed spinach.
A positive effect of cooking was recorded on the antioxidant potential of spinach (cooked in water and by microwave) and eggplant. All three cooking methods showed negative effects on the anticholinesterase activity of potato, spinach and pepper. However, an increase in this activity was recorded for onion, eggplant and carrot. Cooking in water proved to be the worst method for preserving the polyphenols from cooked vegetables and their activities (antioxidant activity and anticholinesterase). The losses of polyphenols are due to their increased solubility in water. However, microwave cooking is suggested as the best method to preserve the polyphenol levels, the antioxidant and anticholinesterase activities of the studied vegetables.
Diplôme : Doctorat en sciences En ligne : ../theses/agronomie/LAI7279.pdf Format de la ressource électronique : Permalink : https://bu.umc.edu.dz/md/index.php?lvl=notice_display&id=10894 Exemplaires
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Titre : Etude phytochimique de deux espèces Crataegus azarolus L. (Rosaceae) et Dioscorea communis L. (Dioscoreaceae). Type de document : texte imprimé Auteurs : Amina Boudjada, Auteur ; Salah Rhouati, Directeur de thèse Editeur : جامعة الإخوة منتوري قسنطينة Année de publication : 2018 Importance : 137 f. Format : 30 cm. Note générale : 2 copies imprimées disponibles
Langues : Français (fre) Tags : Crataegus azarolus Dioscorea communis flavonoides phénanthrènes dihydrophénanthrènes activité antioxydante activité anticholinesterase phenanthrenes dihydrophenanthrenes antioxidant activity anticholinesterase activity Index. décimale : 540 Chimie et sciences connexes Résumé : This work is the subject of a phytochemical and biological study of two medicinal plants belonging to two different families. 1. Crataegus azarolus (L.), belonging to Rosaceae family:
After maceration of the aerial parts of the plant Crataegus azarolus in a methanolic solution and extraction with solvents of increasing polarity, three extracts are obtained. The extracts are separated using chromatographic methods of separation and purification, to lead finally to pure compounds. Then, the GC-MS analysis of a fraction of the CHCl3 extract allowed us to identify five volatile compounds for the first time from this species by comparing their mass spectra with the literature (NIST database). From the AcOEt extract five compounds were isolated, where two acetylated flavonoid glycosids were identified for the first time from the species. From the n-BuOH extract, three flavonoid glycosides are separated by CC and TLC. Their structures are elucidated through spectroscopic analysis methods. The antioxidant activity of the extracts and compounds is evaluated using five different methods (DPPH, ABTS, CUPRAC, FRAP and β-carotene). 2. Dioscorea communis (L.) Caddick & Wilkin, belonging to Dioscoreaceae family: Also, after maceration of the rhizomes of Dioscorea communis in diethyl ether solvent. The Et2O extract obtained was separated by chromatographic techniques (CC, TLC) to finally result in several compounds, seven of which are identified by spectroscopic methods of analyzes (MS, IR, UV, 1D and 2D NMR), where three of them are identified for the first time from this species. Et2O, AcOEt Extracts and some isolated compounds have shown an antioxidant activity by using five different methods (DPPH, ABTS, CUPRAC, FRAP and β-Carrotene), also these extracts and compounds are tested for the first time against acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) enzymes. This study confirmed that the presence of OH groups on the phenanthrene skeleton is essential for its antioxidant and anticholinesterase activities.
Diplôme : Doctorat En ligne : ../theses/chimie/BOU7346.pdf Format de la ressource électronique : Permalink : https://bu.umc.edu.dz/md/index.php?lvl=notice_display&id=10996 Etude phytochimique de deux espèces Crataegus azarolus L. (Rosaceae) et Dioscorea communis L. (Dioscoreaceae). [texte imprimé] / Amina Boudjada, Auteur ; Salah Rhouati, Directeur de thèse . - [S.l.] : جامعة الإخوة منتوري قسنطينة, 2018 . - 137 f. ; 30 cm.
2 copies imprimées disponibles
Langues : Français (fre)
Tags : Crataegus azarolus Dioscorea communis flavonoides phénanthrènes dihydrophénanthrènes activité antioxydante activité anticholinesterase phenanthrenes dihydrophenanthrenes antioxidant activity anticholinesterase activity Index. décimale : 540 Chimie et sciences connexes Résumé : This work is the subject of a phytochemical and biological study of two medicinal plants belonging to two different families. 1. Crataegus azarolus (L.), belonging to Rosaceae family:
After maceration of the aerial parts of the plant Crataegus azarolus in a methanolic solution and extraction with solvents of increasing polarity, three extracts are obtained. The extracts are separated using chromatographic methods of separation and purification, to lead finally to pure compounds. Then, the GC-MS analysis of a fraction of the CHCl3 extract allowed us to identify five volatile compounds for the first time from this species by comparing their mass spectra with the literature (NIST database). From the AcOEt extract five compounds were isolated, where two acetylated flavonoid glycosids were identified for the first time from the species. From the n-BuOH extract, three flavonoid glycosides are separated by CC and TLC. Their structures are elucidated through spectroscopic analysis methods. The antioxidant activity of the extracts and compounds is evaluated using five different methods (DPPH, ABTS, CUPRAC, FRAP and β-carotene). 2. Dioscorea communis (L.) Caddick & Wilkin, belonging to Dioscoreaceae family: Also, after maceration of the rhizomes of Dioscorea communis in diethyl ether solvent. The Et2O extract obtained was separated by chromatographic techniques (CC, TLC) to finally result in several compounds, seven of which are identified by spectroscopic methods of analyzes (MS, IR, UV, 1D and 2D NMR), where three of them are identified for the first time from this species. Et2O, AcOEt Extracts and some isolated compounds have shown an antioxidant activity by using five different methods (DPPH, ABTS, CUPRAC, FRAP and β-Carrotene), also these extracts and compounds are tested for the first time against acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) enzymes. This study confirmed that the presence of OH groups on the phenanthrene skeleton is essential for its antioxidant and anticholinesterase activities.
Diplôme : Doctorat En ligne : ../theses/chimie/BOU7346.pdf Format de la ressource électronique : Permalink : https://bu.umc.edu.dz/md/index.php?lvl=notice_display&id=10996 Exemplaires
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Titre : Composants et potentiel biologique de Cotula anthemoides L et Pentzia monodiana MAIRE. (Asteraceae). Type de document : texte imprimé Auteurs : Wafa Tadrent ép Laouadi, Auteur ; Zahia Kabouche, Directeur de thèse Editeur : جامعة الإخوة منتوري قسنطينة Année de publication : 2018 Importance : 233 f. Format : 30 cm. Note générale : 2 copies imprimées disponibles
Langues : Français (fre) Tags : Cotula anthemoides L Pentzia monodiana Maire Asteraceae lignanes flavonoïdes sesquiterpènes lactones activité antioxydante activité anticholinesterase activité
antityrosinase sesquiterpenes lactones antioxidant activity anticholinesterase activity antityrosinase activity ?????????? lignanes?? ??????? ?? ???????????? ? ?? ???????????Index. décimale : 540 Chimie et sciences connexes Résumé : The present work concerns the phytochemical and biological studies of areal parts of two Algerian plants belonging to the Asteraceae family: Cotula anthemoides L. and Pentzia monodiana Maire. This study led to the isolation and identification of fifteen compounds of Cotula anthemoides and eight compounds of Pentzia monodiana including five phenolic acids, nine flavonoids from which one is new, three lignans, one sesquiterpene lactone, two glycosyl phenolics, a glycosyl acid, a diterpene and an nucleoside. The structural determination of the isolated compounds was established by the use of 1D and 2D NMR spectroscopic techniques (1H, 13C, COSY, HSQC, HMBC and ROESY), by mass spectrometry (ESI-MS and HRESI-MS) and by comparison with the literature data. The evaluation of the antioxidant activity by 4 methods (DPPH, ABTS, CUPRAC and chelating by ferrous ions) of the various extracts, showed a good activity of extracts from P. monodiana compared to those of C. anthemoides. Furthermore, extracts of C. anthemoides showed an interesting anticholinesterase activity. However, both of lignanes, flavonol and flavones substituted in C-3, exhibited better antityrosinase and antiradical activities than some flavones only.
Diplôme : Doctorat En ligne : ../theses/chimie/TAD7353.pdf Format de la ressource électronique : Permalink : https://bu.umc.edu.dz/md/index.php?lvl=notice_display&id=11002 Composants et potentiel biologique de Cotula anthemoides L et Pentzia monodiana MAIRE. (Asteraceae). [texte imprimé] / Wafa Tadrent ép Laouadi, Auteur ; Zahia Kabouche, Directeur de thèse . - [S.l.] : جامعة الإخوة منتوري قسنطينة, 2018 . - 233 f. ; 30 cm.
2 copies imprimées disponibles
Langues : Français (fre)
Tags : Cotula anthemoides L Pentzia monodiana Maire Asteraceae lignanes flavonoïdes sesquiterpènes lactones activité antioxydante activité anticholinesterase activité
antityrosinase sesquiterpenes lactones antioxidant activity anticholinesterase activity antityrosinase activity ?????????? lignanes?? ??????? ?? ???????????? ? ?? ???????????Index. décimale : 540 Chimie et sciences connexes Résumé : The present work concerns the phytochemical and biological studies of areal parts of two Algerian plants belonging to the Asteraceae family: Cotula anthemoides L. and Pentzia monodiana Maire. This study led to the isolation and identification of fifteen compounds of Cotula anthemoides and eight compounds of Pentzia monodiana including five phenolic acids, nine flavonoids from which one is new, three lignans, one sesquiterpene lactone, two glycosyl phenolics, a glycosyl acid, a diterpene and an nucleoside. The structural determination of the isolated compounds was established by the use of 1D and 2D NMR spectroscopic techniques (1H, 13C, COSY, HSQC, HMBC and ROESY), by mass spectrometry (ESI-MS and HRESI-MS) and by comparison with the literature data. The evaluation of the antioxidant activity by 4 methods (DPPH, ABTS, CUPRAC and chelating by ferrous ions) of the various extracts, showed a good activity of extracts from P. monodiana compared to those of C. anthemoides. Furthermore, extracts of C. anthemoides showed an interesting anticholinesterase activity. However, both of lignanes, flavonol and flavones substituted in C-3, exhibited better antityrosinase and antiradical activities than some flavones only.
Diplôme : Doctorat En ligne : ../theses/chimie/TAD7353.pdf Format de la ressource électronique : Permalink : https://bu.umc.edu.dz/md/index.php?lvl=notice_display&id=11002 Exemplaires
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