LEREESI research documents

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Laboratory of Renewable Energy, Energy Efficiency and Smart Systems

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End date: 2016

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    Flavonoid glycosides and triterpenoids from Atractylis flava
    (ELSEVIER, 2012-10-24) Chabani, Sonia; Haba, Hamada; Lavaud, Catherine; Benkhaled, Mohammed; Harakat, Dominique
    Two new flavonoid glycosides, together with twelve known compounds including seven flavonoids and five triterpenoids were isolated from the whole plant Atractylis flava Desf. The structures of new compounds have been elucidated as 6-hydroxykaempferol 6-methyl ether 7-O-β-glucopyranuronoside (1) and isorhamnetin 3-O-[(6″′-O-E-feruloyl)-β-d-glucopyranosyl-(1 → 2)]-β-d-galactopyranoside (2) named Atraflavoside A and B successively, on the basis of physical and spectroscopic analysis, including 1D and 2D NMR (1H, 13C, COSY, TOCSY, HSQC, HMBC and NOESY) and mass spectrometry (HRESIMS) whereas those of the known compounds (3–14) were established by spectral comparison with those published in the literature.
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    Three new oleanane-type triterpene saponins from Atractylis flava
    (ELSEVIER, 2015-12-11) Chabani, Sonia; Lavaud, Catherine; Benkhaled, Mohammed; Harakat, Dominique; Long, Christophe; Haba, Hamada
    Three new bidesmosidic saponins (1–3), along with thirteen known metabolites consisting of two flavonoids and eleven triterpenoids were identified in dichloromethane and n-butanol extracts of the whole plant Atractylis flava Desf. The saponins were characterized as 3-O-[β-d-glucuronopyranosyl]-28-O-[β-d-xylopyranosyl-(1 → 4)-α-l-rhamnopyranosyl-(1 → 2)-β-d-xylopyranosyl]-16α-hydroxygypsogenic acid (1), 3-O-[β-d-glucuronopyranosyl]-28-O-[β-d-xylopyranosyl-(1 → 4)-α-l-rhamnopyranosyl-(1 → 2)-α-l-arabinopyranosyl]-16α-hydroxygypsogenic acid (2), and 3-O-[β-d-galactopyranosyl-(1 → 2)-β-d-glucuronopyranosyl]-28-O-[((3-O-acetyl)-β-d-xylopyranosyl)-(1 → 4)-((2-O-acetyl)-α-l-rhamnopyranosyl)-(1 → 2)-β-d-xylopyranosyl]-quillaic acid (3). Structures of all isolated compounds were elucidated by spectroscopic analysis, including 1D and 2D NMR (1H, 13C, COSY, HSQC, TOCSY, HSQC-TOCSY, HMBC, ROESY and NOESY), high-resolution electrospray ionization mass spectrometry (HRESIMS), acid hydrolysis, measurement of optical rotation and comparison with literature data.
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    Chemical composition of medicinal plant Atractylis serratuloides
    (ELSEVIER, 2016-03-05) Chabani, Sonia; Haba, Hamada; Long, Christophe; Benkhaled, Mohammed
    Phytochemical investigation of the roots of Atractylis serratuloides Sieber ex Cass. (Asteraceae) led to the isolation of nine compounds 1–9 including eight triterpenoids and one phenolic compound. Their structures were established on the basis of physical and spectroscopic analysis, including 1D and 2D NMR (1H, 13C, COSY, HSQC, and HMBC), mass spectrometry ESI, and by comparison with those published in the literature. Triterpenoids are typical compounds of Atractylis genus and could be useful as characteristic markers in chemotaxonomic research. In addition, isolated triterpenoids have previously showed many biological activities and might explain the use of A. serratuloides in traditional medicine.
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    Method for Indexing and Identifying Multimedia Documents
    (European Patent Office, 2005-06-16) Essafi Hassane; Guezouli Larbi; Sayah Salima; Behloul Ali; Mandridake Clarisse; Essafi Louafi
    The method for indexing multimedia documents comprises the following steps: (a) identification and extraction, for each document, of terms ti comprising vectors characterizing the properties of the document; (b) storage of terms ti in a term base comprising P terms; (c) determination of a maximum number N of desired concepts including the most relevant terms ti; (d) calculation of the matrix T of distances between the terms ti of the term base, (e) decomposition of the set P of terms ti of the term base into N parts Pj (1=j=N) such that P = P1 UP2 UPj UPN, each part Pj comprising a set of terms tij and being represented by a concept cj, terms ti being divided in such a manner that the furthermost terms are located in distinct parts Pl, Pm and the nearest terms are located in the same part Pl; (f) structuring of the dictionary of concepts and (g) construction of a prints base consisting of the set of concepts ci representing the terms ti of said documents, each document being associated with a print which is proper thereto.
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    Introduction au Calcul Formel: Maple & CAML
    (Éditions Universitaires Européennes, 2016-01-01) Guezouli Larbi
    Le calcul formel est un type de calcul qui permet de manipuler les grands nombres dans des calculs intensifs en utilisant des algorithmes optimisés dans le but de minimiser le temps de calcul. Appelé aussi calcul symbolique, pour compléter les méthodes de calcul numérique. Les logiciels de calcul formel ont beaucoup évolué au cours de ces dernières années. Ils sont destinés aux mathématiciens, aux informaticiens et aux utilisateurs qui utilisent les mathématiques comme les électroniciens, les mécaniciens, ... Ce document est destiné aux étudiants de la première année Licence tronc commun Math-Informatique. Il décrit un cours de 20 heures avec 20 heures de travaux pratiques. Les points traités dans ce cours sont indispensables pour pouvoir utiliser un logiciel de calcul formel. Les logiciels étudiés dans ce cours sont Maple et Caml.