| 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) |
| Catégories : |
Français - Anglais
Chimie
|
| Tags : |
Cistaceae Helianthemum ruficomum Helianthemum confertum RMN 1D RMN
2D TEAC ORAC HPLC-ABTS ' + Activité antioxydante Piégeage radicalaire ID
NMR Antioxidant activity Radical scavenging
activity |
| Index. 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 : |
pdf |
| Permalink : |
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 . - جامعة الإخوة منتوري قسنطينة, 2017 . - 270 f. ; 30 cm. 2 copies imprimées disponibles
Langues : Français ( fre)
| Catégories : |
Français - Anglais
Chimie
|
| Tags : |
Cistaceae Helianthemum ruficomum Helianthemum confertum RMN 1D RMN
2D TEAC ORAC HPLC-ABTS ' + Activité antioxydante Piégeage radicalaire ID
NMR Antioxidant activity Radical scavenging
activity |
| Index. 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 : |
pdf |
| Permalink : |
index.php?lvl=notice_display&id=10491 |
|
Valorisation genre helianthemum- de plantes sahariennes activité antioxydante endémiques du genre Helianthemum -activité antioxydante
