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Partager le résultat de cette recherche Interroger des sources externesValorisation genre helianthemum- de plantes sahariennes activité antioxydante endémiques du genre Helianthemum -activité antioxydante / Yasmine Chemam
Titre : Valorisation genre helianthemum- de plantes sahariennes activité antioxydante endémiques du genre Helianthemum -activité antioxydante Type de document : texte imprimé Auteurs : Yasmine Chemam, Auteur ; Fadila Benayache, Directeur de thèse ; Eric Marchioni, Directeur de thèse Editeur : جامعة الإخوة منتوري قسنطينة Année de publication : 2017 Importance : 270 f. Format : 30 cm. Note générale : 2 copies imprimées disponibles
Langues : Français (fre) Tags : Cistaceae Helianthemum ruficomum Helianthemum confertum RMN 1D RMN
2D TEAC ORAC HPLC-ABTS ' + Activité antioxydante Piégeage radicalaire ID
NMR Antioxidant activity Radical scavenging
activityIndex. décimale : 540 Chimie et sciences connexes Résumé : This work is the assessment of a study that we conducted on two endemic plants
of the septentrional Sahara from the Cistaceae family: Helianthemum ruficomum and
Helianthemum confertum. To our best knowledge, no studies are reported so far for these
species. The purpose of this work was to investigate the chemical composition and the
radical scavenging capacity of these species and their isolated components.
The ethyl acetate and «-butanol soluble parts of the aqueous-ethanol extracts of the
aerial parts of these species were evaluated for their free radical scavenging capacity by
ABTS'+ assay. The obtained data which showed important antioxidant powers were
confirmed by TEAC and ORAC assays. On-line HPLC- ABTS'+ assays were then applied to
screen the extracts. The results which revealed remarcable wealth in antioxidants allowed
guiding the fractionation of the extracts by column chromatography on silica gel 60. The
obtained fractions were purified by chromatography on preparative plates of silica
gel 60 and/or by semi-preparative reverse phase HPLC leading to the isolation and the
identification of 14 compounds from H. ruficomum and 6 compounds from H confertum. The
compounds were identified by spectral analyses, mainly ESI-HRMS (+), UV, ID NMR (*H,
13C, DEPT) and 2D NMR (DOSY, COSY, NOESY, HSQC and HMBC) and comparison of
their spectroscopic data with those reported in the literature.
The antioxidant power of the isolated compounds was also evaluated by on-line
HPLC-ABTS'+, TEAC and ORAC. The results clearly indicate high antioxidant potential
of the extracts and tested compounds isolated from these two species.
This work was the object of a published paper and two other in progress.Diplôme : Doctorat En ligne : ../theses/chimie/CHE7110.pdf Format de la ressource électronique : Permalink : https://bu.umc.edu.dz/md/index.php?lvl=notice_display&id=10491 Valorisation genre helianthemum- de plantes sahariennes activité antioxydante endémiques du genre Helianthemum -activité antioxydante [texte imprimé] / Yasmine Chemam, Auteur ; Fadila Benayache, Directeur de thèse ; Eric Marchioni, Directeur de thèse . - [S.l.] : جامعة الإخوة منتوري قسنطينة, 2017 . - 270 f. ; 30 cm.
2 copies imprimées disponibles
Langues : Français (fre)
Tags : Cistaceae Helianthemum ruficomum Helianthemum confertum RMN 1D RMN
2D TEAC ORAC HPLC-ABTS ' + Activité antioxydante Piégeage radicalaire ID
NMR Antioxidant activity Radical scavenging
activityIndex. décimale : 540 Chimie et sciences connexes Résumé : This work is the assessment of a study that we conducted on two endemic plants
of the septentrional Sahara from the Cistaceae family: Helianthemum ruficomum and
Helianthemum confertum. To our best knowledge, no studies are reported so far for these
species. The purpose of this work was to investigate the chemical composition and the
radical scavenging capacity of these species and their isolated components.
The ethyl acetate and «-butanol soluble parts of the aqueous-ethanol extracts of the
aerial parts of these species were evaluated for their free radical scavenging capacity by
ABTS'+ assay. The obtained data which showed important antioxidant powers were
confirmed by TEAC and ORAC assays. On-line HPLC- ABTS'+ assays were then applied to
screen the extracts. The results which revealed remarcable wealth in antioxidants allowed
guiding the fractionation of the extracts by column chromatography on silica gel 60. The
obtained fractions were purified by chromatography on preparative plates of silica
gel 60 and/or by semi-preparative reverse phase HPLC leading to the isolation and the
identification of 14 compounds from H. ruficomum and 6 compounds from H confertum. The
compounds were identified by spectral analyses, mainly ESI-HRMS (+), UV, ID NMR (*H,
13C, DEPT) and 2D NMR (DOSY, COSY, NOESY, HSQC and HMBC) and comparison of
their spectroscopic data with those reported in the literature.
The antioxidant power of the isolated compounds was also evaluated by on-line
HPLC-ABTS'+, TEAC and ORAC. The results clearly indicate high antioxidant potential
of the extracts and tested compounds isolated from these two species.
This work was the object of a published paper and two other in progress.Diplôme : Doctorat En ligne : ../theses/chimie/CHE7110.pdf Format de la ressource électronique : Permalink : https://bu.umc.edu.dz/md/index.php?lvl=notice_display&id=10491 Exemplaires
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Titre : Synthèse, caractérisation et évaluation biologique de nouveaux dérivés poly-hétérocycliques à base d’imidazole Type de document : texte imprimé Auteurs : Houssem Boulebd, Auteur ; Ali Belfaitah, Directeur de thèse Editeur : جامعة الإخوة منتوري قسنطينة Année de publication : 2016 Importance : 257 f. Format : 30 cm. Note générale : 2 copies imprimes disponibles Langues : Français (fre) Tags : Chimie organique Imidazole halogénation poly-hétérocycles Maladie d’Alzheimer analogues de la
Tacrine hépatotoxicité ORAC activité biologique ????????? ????? ????? ??????? ????? ??????? ??? ???????? ????????????? ???? ORAC?????? ????????
Imidazole halogenation poly-heterocyclic compounds Alzheimer's disease
tacrine analogues hepatotoxicity biological activityIndex. décimale : 540 Chimie et sciences connexes Résumé : Some 2-halo-(1-methyl-1H-imidazole) derivatives were prepared by selective halogenation
reaction (bromination, chlorination and iodination). The addition of -bromoacetophenone to
2-bromo(chloro)-1-methyl-1H-imidazole allowed us to access to corresponding imidazolium
salts in satisfactory yields (47-64%). The reactivity of 2-halogeno-N-phenyl-1-methyl-1Himidazolium bromide with activated methylene compounds of diverse structures has been
studied.
A series of original heterocyclic products composed of a core 1-methyl-1H-imidazole
associated at 2-position to highly functionalized heterocyclic compounds such as 4H-pyran,
chromene, benzo (pyrido) chromenes, 1,4-dihydropyridine, pyridine, quinazoline, pyrrolidines
and other pyrazolines have been prepared.
It will be noted that upon addition of methyl ketone derivatives, 1-methylimidazole-pyridine
hybrid compounds obtained are accompanied by the formation of corresponding 2,6-
dicyanoaniline derivatives in low yields. The adaptation of the operating conditions enabled us
to selectively direct the reaction towards the formation of new 2,6-dicyanoaniline derivatives
in good yields for aliphatic methyl ketone derivatives (62-70%), and in 45 % of yield for
acetophenone. These compounds are also fluorescent.
Some series of hybrid compounds such as (1-methyl-1H-imidazol-2-yl)-4H-pyran, -
pyridine, -1,4-dihydropyridine and -quinazoline have been subjected to an in vitro assessment
of their antimicrobial, and antioxydante (DPPH) activities, and also for their hepatotoxicity
towards liver cells HepG2 in a gradient concentration from 1M to 300M, and a structureactivity relationship (SAR) has been demonstrated.
A "valorization" of (1-methyl-1H-imidazol-2-yl)-4-pyran hybrid derivatives was undertaken
and resulted in the preparation of some original series of highly and diversely functionalized
Tacrine analogues (Tacrine is a drug used in the treatment of Alzheimer's disease) as
pyranotacrines. These novel racemic Tacrine analogues are siginificantly less hepatotoxic than
Tacrine, retaining potent, and selective EeAChE inhibition with IC50 values in the M range,
with a remarkable antioxydant effect.
Yields are good in most cases. All prepared compounds were identified by the usual
spectroscopic methods (IR, 1H NMR and 13C NMR), and for some of them additional analyzes
were carried out (elemental analysis and / or X-ray diffraction).Diplôme : Doctorat En ligne : ../theses/chimie/BOU6833.pdf Format de la ressource électronique : Permalink : https://bu.umc.edu.dz/md/index.php?lvl=notice_display&id=10125 Synthèse, caractérisation et évaluation biologique de nouveaux dérivés poly-hétérocycliques à base d’imidazole [texte imprimé] / Houssem Boulebd, Auteur ; Ali Belfaitah, Directeur de thèse . - [S.l.] : جامعة الإخوة منتوري قسنطينة, 2016 . - 257 f. ; 30 cm.
2 copies imprimes disponibles
Langues : Français (fre)
Tags : Chimie organique Imidazole halogénation poly-hétérocycles Maladie d’Alzheimer analogues de la
Tacrine hépatotoxicité ORAC activité biologique ????????? ????? ????? ??????? ????? ??????? ??? ???????? ????????????? ???? ORAC?????? ????????
Imidazole halogenation poly-heterocyclic compounds Alzheimer's disease
tacrine analogues hepatotoxicity biological activityIndex. décimale : 540 Chimie et sciences connexes Résumé : Some 2-halo-(1-methyl-1H-imidazole) derivatives were prepared by selective halogenation
reaction (bromination, chlorination and iodination). The addition of -bromoacetophenone to
2-bromo(chloro)-1-methyl-1H-imidazole allowed us to access to corresponding imidazolium
salts in satisfactory yields (47-64%). The reactivity of 2-halogeno-N-phenyl-1-methyl-1Himidazolium bromide with activated methylene compounds of diverse structures has been
studied.
A series of original heterocyclic products composed of a core 1-methyl-1H-imidazole
associated at 2-position to highly functionalized heterocyclic compounds such as 4H-pyran,
chromene, benzo (pyrido) chromenes, 1,4-dihydropyridine, pyridine, quinazoline, pyrrolidines
and other pyrazolines have been prepared.
It will be noted that upon addition of methyl ketone derivatives, 1-methylimidazole-pyridine
hybrid compounds obtained are accompanied by the formation of corresponding 2,6-
dicyanoaniline derivatives in low yields. The adaptation of the operating conditions enabled us
to selectively direct the reaction towards the formation of new 2,6-dicyanoaniline derivatives
in good yields for aliphatic methyl ketone derivatives (62-70%), and in 45 % of yield for
acetophenone. These compounds are also fluorescent.
Some series of hybrid compounds such as (1-methyl-1H-imidazol-2-yl)-4H-pyran, -
pyridine, -1,4-dihydropyridine and -quinazoline have been subjected to an in vitro assessment
of their antimicrobial, and antioxydante (DPPH) activities, and also for their hepatotoxicity
towards liver cells HepG2 in a gradient concentration from 1M to 300M, and a structureactivity relationship (SAR) has been demonstrated.
A "valorization" of (1-methyl-1H-imidazol-2-yl)-4-pyran hybrid derivatives was undertaken
and resulted in the preparation of some original series of highly and diversely functionalized
Tacrine analogues (Tacrine is a drug used in the treatment of Alzheimer's disease) as
pyranotacrines. These novel racemic Tacrine analogues are siginificantly less hepatotoxic than
Tacrine, retaining potent, and selective EeAChE inhibition with IC50 values in the M range,
with a remarkable antioxydant effect.
Yields are good in most cases. All prepared compounds were identified by the usual
spectroscopic methods (IR, 1H NMR and 13C NMR), and for some of them additional analyzes
were carried out (elemental analysis and / or X-ray diffraction).Diplôme : Doctorat En ligne : ../theses/chimie/BOU6833.pdf Format de la ressource électronique : Permalink : https://bu.umc.edu.dz/md/index.php?lvl=notice_display&id=10125 Exemplaires
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Titre : Recherche et détermination structurale de métabolites secondaires de deux plantes Algériennes de la famille des lamiaceae Type de document : texte imprimé Auteurs : Sabrina Mohamadi, Auteur ; Samir Benayache, Directeur de thèse Editeur : جامعة الإخوة منتوري قسنطينة Année de publication : 2016 Importance : 334 f. Format : 30 cm. Note générale : 2 copies imprimées disponibles
Langues : Français (fre) Tags : UV-visible SM-MR RMN,1H 13C cosy noesy HSQC HMBC ABTS ORAC DPPH ??? ??????? ?????? ??????? ?????? ??? ????????? ??????? ?????? ????? ????? ??????? ?????? ?????????? Index. décimale : 540 Chimie et sciences connexes Résumé : This work deals with the structural determination and biological evaluation of natural substances isolated from two species of the Lamiaceae family (Salvia aegyptiaca and Saccocalyx satureioides). These family and the genus Salvia are known for their rich antioxidant compounds including polyphenols and flavonoids.
The phytochemical study of the aerial parts of these species allowed after extraction, separation and purification the isolation and identification of nineteen compounds from Saccocalyx satureioides and fourteen compounds from Salvia aegyptiaca .These compounds were identified by the combination of spectroscopic methods including : UV-visible absorption spectroscopy, high resolution HR-MS mass spectrometry, 1H and 13C-NMR and two-dimensional experiments (COSY, NOESY, HSQC, and HMBC) The isolated compounds were :
A flavonol : Quercetin (14).
Fifteen flavones : 7-methyl- sudachitin (8), Sideritiflavone (17), Luteolin (25),
Apigenin (27), Salvigenin(28), 4',7-dimethylapigenin (29), 5-hydroxy 3', 4', 6,7-
tetraméthoxyflavone(30), IsoIscutellarein-7-O-allosyl (1→2) glucoside (11),Isoscutellarein-7-O-[ β-D-allopyranosyl-(1→2)]-6’’-O-acetyl- β-D-glucopyranoside
(12), Isoscutellarein-7-O-[6”’-O-acetyl- β-D-allopyranosyl-(1→2)]- β-Dglucopyranoside (13) , Isoscutellarein -7-O-[6‴-O -acetyl-β-D-allopyranosyl (1→2) ]-
6″-O-acetyl-β-D-glucopyranoside. (15), Apigenin- 7-O-(6’’-trans-p-coumaroyl- β -Dglucopyranoside (16), Luteolin 7-O glucoside (21), Apigenine 7-O glucoside (22),
Diosmin (23).
Sixteen phenolic compounds : Piceol(1), Vanillin (2), Ferulic aldehyde (3), 3,3’-bis (3,4-
dihydro-4-hydroxy-6,8-dimethoxy-2H-1-benzopyran) (4), 3,3’-bis (3,4-dihydro-4-
hydroxy-6-methoxy-2H-1-benzopyran) (5), Dimethylcaffeic acid (6), Balanophonin (7),
Caffeic acid (9), p-coumaric acid (10), 4-methoxyphenol, Salicylic acid, Caffeic acide
(18), Vanillic acid (19), Syringic acid (20), Rosmarinic acid (24), Methyl rosmarinate
(26).
A furocoumarin : 6`,7`-dihydroxybergamottin(31)The study of the chemical composition of essential oil of Salvia aegyptiaca species growing in
Algeria was characterized by a high level of sesquiterpene fraction and a moderate level of
monoterpene components. β-caryophyllene (10.2%), Selina-4,11-diene (9.7%), bornyl acetate
(8.5%), β-gurjunene (7.6%), germacrene D (7.0 %) and β-caryophyllene oxide (6.2%) were the
major components of this essential oil.
This work led to the publications of two articles subject entitled “ On-line screening and
identification of antioxidant phenolic compounds of Saccocalyx satureioides Coss. et Dur.” and
“ Chemical composition of the Essential oil of Salvia aegyptiaca” . A third paper is in
preparation and will be devoted to the phytochemical and biological study of Salvia aegyptiaca.
Diplôme : Doctorat En ligne : ../theses/chimie/MOH6938.pdf Format de la ressource électronique : Permalink : https://bu.umc.edu.dz/md/index.php?lvl=notice_display&id=10289 Recherche et détermination structurale de métabolites secondaires de deux plantes Algériennes de la famille des lamiaceae [texte imprimé] / Sabrina Mohamadi, Auteur ; Samir Benayache, Directeur de thèse . - [S.l.] : جامعة الإخوة منتوري قسنطينة, 2016 . - 334 f. ; 30 cm.
2 copies imprimées disponibles
Langues : Français (fre)
Tags : UV-visible SM-MR RMN,1H 13C cosy noesy HSQC HMBC ABTS ORAC DPPH ??? ??????? ?????? ??????? ?????? ??? ????????? ??????? ?????? ????? ????? ??????? ?????? ?????????? Index. décimale : 540 Chimie et sciences connexes Résumé : This work deals with the structural determination and biological evaluation of natural substances isolated from two species of the Lamiaceae family (Salvia aegyptiaca and Saccocalyx satureioides). These family and the genus Salvia are known for their rich antioxidant compounds including polyphenols and flavonoids.
The phytochemical study of the aerial parts of these species allowed after extraction, separation and purification the isolation and identification of nineteen compounds from Saccocalyx satureioides and fourteen compounds from Salvia aegyptiaca .These compounds were identified by the combination of spectroscopic methods including : UV-visible absorption spectroscopy, high resolution HR-MS mass spectrometry, 1H and 13C-NMR and two-dimensional experiments (COSY, NOESY, HSQC, and HMBC) The isolated compounds were :
A flavonol : Quercetin (14).
Fifteen flavones : 7-methyl- sudachitin (8), Sideritiflavone (17), Luteolin (25),
Apigenin (27), Salvigenin(28), 4',7-dimethylapigenin (29), 5-hydroxy 3', 4', 6,7-
tetraméthoxyflavone(30), IsoIscutellarein-7-O-allosyl (1→2) glucoside (11),Isoscutellarein-7-O-[ β-D-allopyranosyl-(1→2)]-6’’-O-acetyl- β-D-glucopyranoside
(12), Isoscutellarein-7-O-[6”’-O-acetyl- β-D-allopyranosyl-(1→2)]- β-Dglucopyranoside (13) , Isoscutellarein -7-O-[6‴-O -acetyl-β-D-allopyranosyl (1→2) ]-
6″-O-acetyl-β-D-glucopyranoside. (15), Apigenin- 7-O-(6’’-trans-p-coumaroyl- β -Dglucopyranoside (16), Luteolin 7-O glucoside (21), Apigenine 7-O glucoside (22),
Diosmin (23).
Sixteen phenolic compounds : Piceol(1), Vanillin (2), Ferulic aldehyde (3), 3,3’-bis (3,4-
dihydro-4-hydroxy-6,8-dimethoxy-2H-1-benzopyran) (4), 3,3’-bis (3,4-dihydro-4-
hydroxy-6-methoxy-2H-1-benzopyran) (5), Dimethylcaffeic acid (6), Balanophonin (7),
Caffeic acid (9), p-coumaric acid (10), 4-methoxyphenol, Salicylic acid, Caffeic acide
(18), Vanillic acid (19), Syringic acid (20), Rosmarinic acid (24), Methyl rosmarinate
(26).
A furocoumarin : 6`,7`-dihydroxybergamottin(31)The study of the chemical composition of essential oil of Salvia aegyptiaca species growing in
Algeria was characterized by a high level of sesquiterpene fraction and a moderate level of
monoterpene components. β-caryophyllene (10.2%), Selina-4,11-diene (9.7%), bornyl acetate
(8.5%), β-gurjunene (7.6%), germacrene D (7.0 %) and β-caryophyllene oxide (6.2%) were the
major components of this essential oil.
This work led to the publications of two articles subject entitled “ On-line screening and
identification of antioxidant phenolic compounds of Saccocalyx satureioides Coss. et Dur.” and
“ Chemical composition of the Essential oil of Salvia aegyptiaca” . A third paper is in
preparation and will be devoted to the phytochemical and biological study of Salvia aegyptiaca.
Diplôme : Doctorat En ligne : ../theses/chimie/MOH6938.pdf Format de la ressource électronique : Permalink : https://bu.umc.edu.dz/md/index.php?lvl=notice_display&id=10289 Exemplaires
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