Intraspecific chemical variability of the leaf essential oil of Juniperus phoenicea subsp. turbinata from Corsica

The composition of 50 samples of essential oil of individual plants of Juniperus phoenicea subsp. turbinata from Corsica was investigated by GC, GC-MS and 13C NMR. [alpha]-Pinene, [beta]-phellandrene, [alpha]-terpinyl acetate, [Delta]-3-carene, myrcene and [alpha]-phellandrene were found to be the main constituents. The results were submitted to cluster analysis and discriminant analysis which allowed two groups of essential oils to be distinguished with respect to the content of [alpha]-pinene, [beta]-phellandrene and [alpha]-terpinyl acetate.http://www.sciencedirect.com/science/article/B6T4R-41TMSRJ-8/1/9a99aea13c1425fdcac449056f51c71

Chemical composition of laurencia obtusa extract and isolation of a new C15-acetogenin

A new C15-acetogenin, sagonenyne (20), exhibiting an unusual single tetrahydropyran ring was isolated from an ethyl acetate extract of Laurencia obtusa collected on the Corsican coastline. Its structure was established by detailed NMR spectroscopic analysis, mass spectrometry, and comparison with literature data. Twenty-three known compounds were identified in the same extract by means of column chromatography steps, using a (13)C-NMR computer aided method developed in our laboratory. In addition to sesquiterpenes, which represent the main chemical class of this extract, diterpenes, sterols, and C15-acetogenins were identified. The crude extract was submitted to a cytotoxicity assay and was particularly active against THP-1 cells, a human leukemia monocytic cell line.info:eu-repo/semantics/publishedVersio

La RMN du carbone-13, outil d'analyse : contribution à l'étude d'huiles essentielles du Viet-Nam et d'un liquide de pyrolyse de la biomasse

CETTE ÉTUDE A POUR OBJECTIF DE CONTRIBUER AU DÉVELOPPEMENT DE LA RMN DU CARBONE-13 EN TANT QU'OUTIL D'IDENTIFICATION ET DE QUANTIFICATION DES CONSTITUANTS DES MÉLANGES COMPLEXES NATURELS ET D'APPLIQUER CETTE TECHNIQUE A LA CARACTÉRISATION D'HUILES ESSENTIELLES DU VIET-NAM ET D'UN LIQUIDE DE PYROLYSE DE LA BIOMASSE. LES DONNÉES CHROMATOGRAPHIQUES ET SPECTROSCOPIQUES (RMN DU CARBONE-13) DE COMPOSES LINÉAIRES NON TERPÉNIQUES DIVERSEMENT FONCTIONNALISES (ALCOOLS, ACETATES ET ALDEHYDES, SATURES ET INSATURES) ONT ETE DETERMINEES. LES VALEURS DE DÉPLACEMENTS CHIMIQUES DES CARBONES ALIPHATIQUES C4 ET C5 DES ALDEHYDES a,b-INSATURES ONT ETE COMPARÉES A CELLES DES ALCOOLS CORRESPONDANTS. CES CARBONES PRÉSENTENT RESPECTIVEMENT UN LÉGER DEBLINDAGE ET BLINDAGE DU VRAISEMBLABLEMENT A LA CONJUGAISON ET INDÉPENDANTS DE LA LONGUEUR DE LA CHAINE CARBONÉE. L'ÉTUDE DETAILLEE PAR RMN DU CARBONE-13 D'UNE HUILE ESSENTIELLE DE PIPER BAVINUM DU VIET-NAM A PERMIS D'EXPLICITER LA MÉTHODE D'ANALYSE. LA COMPOSITION CHIMIQUE DE DIVERSES HUILES ESSENTIELLES VIETNAMIENNES A ETE DÉTERMINEE PAR COMBINAISON DE LA CPG(IR), DE LA CPG-SM ET DE LA RMN DU CARBONE-13. CERTAINES D'ENTRE ELLES SONT DÉCRITES POUR LA PREMIERE FOIS ET D'AUTRES POSSEDENT UNE ACTIVITÉ ANTIBACTERIENNE. UN LIQUIDE DE PYROLYSE DE LA BIOMASSE A ETE FRACTIONNE. LES FRACTIONS OBTENUES ONT ETE ANALYSÉES PAR DIVERSES TECHNIQUES ANALYTIQUES (ANALYSE ELEMENTAIRE, CES, IRTF, CPG-SM ET RMN DU CARBONE-13). LA PRÉSENCE DE TROIS GRANDES FAMILLES DE COMPOSES A ETE MISE EN ÉVIDENCE: DES ALCANES (SATURES ET INSATURES), DES SUCRES ANHYDRES ET DES COMPOSES PHÉNOLIQUES (MONOMERES ET OLIGOMERES). LES OLIGOMERES POSSEDENT UNE MASSE POUVANT DÉPASSER 5000 G.MOL-1. ENFIN, UNE SÉQUENCE QUANTITATIVE PAR RMN DU CARBONE-13 A ETE MISE EN OEUVRE POUR DÉTERMINER LA PROPORTION D'HYDROXYACETALDEHYDE (PRÉSENT SOUS DIVERSES FORMES MONOMERES ET DIMERES) DANS LES LIQUIDES DE PYROLYSE.THE OBJECTIVE OF THIS STUDY WAS A CONTRIBUTION TO THE DEVELOPMENT OF THE 13C NMR AS A TOOL FOR IDENTIFICATION AND QUANTITATIVE DETERMINATION OF THE COMPONENTS OF NATURAL MIXTURES. THIS TECHNIQUE WAS APPLIED TO THE CARACTERIZATION OF ESSENTIAL OILS FROM VIETNAM AND A BIO-OIL. THE CHROMATOGRAPHIC AND SPECTROSCOPIC DATA OF ACYCLIC, NON TERPENIC COMPOUNDS, BEARING DIFFERENT FRACTIONS (ALCOHOLS, ACETATES AND ALDEHYDES, SATURED AND UNSATURED) WERE DETERMINED. THE SIGNALS OF THE C4 AND C5 CARBONS OF a,b-UNSATURED ALDEHYDES WERE DESHIELDED AND SHIELDED RESPECTIVELY, COMPARED WITH THOSE OF THE CORRESPONDING ALCOHOLS. THESE DIFFERENCES ARE PROBABLY THE CONSEQUENCE OF CONJUGATION AND ARE NO DEPENDANT OF THE CHAIN LENGTH. A DETAILED AN ALYSIS BY 13C NMR OF THE ESSENTIAL OIL OF PIPER BAVINUM FROM VIETNAM ALLOWED THE DIRECT IDENTIFICATION OF 38 COMPONENTS. THE CHEMICAL COMPOSITION OF VARIOUS ESSENTIAL OILS FROM VIETNAM WAS DETERMINED BY COMBINATION OF GC(RI), GC-MS AND 13C NMR. THE COMPOSITION OF SOME OF THESE OILS WAS REPORTED FOR THE FIRST TIME AND SOME OTHERS OILS EXHIBITED AN ANTIBACTERIAL ACTIVITY. A BIO-OIL WAS FRACTIONATED AND THE FRACTIONS WERE ANALYSED BY COMPLEMENTARY ANALYTICAL TECHNIQUES (GPC, IRFT, GC-MS AND 13C NMR). THREE FAMILIES OF COMPONENTS WERE DISTINGUISHED: ALCANES, ANHYDROSUGARS AND PHENOLIC COMPOUNDS (MONOMERS AND OLIGOMERS). THE OLIGOMERS HAVE A MASS UP TO 5000 G.MOL-1. FINALLY, A QUANTITATIVE SEQUENCE WAS IMPLEMENTED TO DETERMINE, BY 13C NMR, THE CONTENT OF HYDROXYACETALDEHYDE (MONOMERIC AND DIMERIC FORMS) IN THE BIO-OILS.CORTE-BU (200962101) / SudocSudocFranceF

Analyse par RMN1H et RMN13C d'huiles essentielles et d'extraits (cedrus atlantica G. Manetti et Taxus baccata Linné)

Les produits naturels issus de la biomasse végétale connaissent depuis quelques années un succès grandissant dans de nombreuses industries (pharmacie, agroalimentaire, parfums et cosmétiques). L objectif de notre étude était, d une part de contribuer au développement des méthodes d identification et de quantification des constituants des mélanges naturels par RMN 13C et MN1H, et d autre part, de contribuer à la caractérisation chimique de végétaux poussant en Corse en vue d une valorisation potentielle. La première partie de nos travaux concerne la caractérisation chimique de l huile essentielle de bois de cèdre de l Atlas, Cedrus atlantica Manetti, introduit en Corse et présent dans diverses forêts. L analyse détaillée d un échantillon de cette huile essentielle, réalisée par combinaison de techniques chromatographiques et spectroscopiques, nous a permis d identifier divers composés possédant le squelette himachalane ou bisabolane non encore référencés dans la bibliothèque de spectres Terpènes propre au laboratoire. Il s agit de la (E)- -atlantone, de la (Z)- -atlantone, de l himachalol et de l allohimachalol. L'analyse de 48 échantillons obtenus à partir d arbres situés dans les 5 forêts référencées par l Office National des Forêts de Corse (Bavella, Bonifato, l Ospedale, Pineta et Vizzavona) et dans quelques stations isolées, associée au traitement statistique des résultats (ACP, k-means et classification hiérarchique ascendante), a permis de mettre en évidence la variabilité chimique intraspécifique de cette huile essentielle. Les échantillons se répartissent en deux groupes, de compositions chimiques très rarement décrites dans la littérature, en fonction de leur teneur élevée en -pinène (groupe I) ou en himachalol (groupe II). Notre deuxième objectif était de contribuer au développement de la méthode d analyse des taxanes en mélange par RMN 13C, développée au laboratoire. Pour ce faire, nous avons dans un premier temps, mis en œuvre deux protocoles de fractionnement d extraits au méthanol et à l éthanol de feuilles d if (Taxus baccata L.) de Corse. Nous avons ainsi identifié 11 taxanes, dont 5 non encore référencés dans la bibliothèque de spectres taxanes du laboratoire (désacétyltaxine B, 5-cinnamoyltaxicine I, 2,9-désacétyltaxinine, 3,11-cyclotaxinine NN2 et 2-désacétyltaxinine J). Dans un second temps, nous avons mis au point et validé une méthode de quantification des taxanes par RMN 13C en utilisant la 10-désacétylbaccatine III (10-DAB III) comme composé modèle et l hexane-1,6-diol comme référence interne. Cette méthode pouvant être extrapolée aux composés possédant le squelette taxane, nous l avons appliquée à la quantification de ces derniersdans les extraits au solvant de T. baccata. Dans une dernière partie, nous avons mis au point et validé (justesse, linéarité et précision des mesures) un protocole expérimental de quantification par RMN 1H sur 39 terpènes purs appartenant à différentes familles chimiques (oléfines, alcools, cétones, aldéhydes, esters, oxydes, phénylpropanoïdes, azotés) puis en mélange. Cette procédure quantitative s est avérée fiable, rapide et complémentaire de la CPG. Elle a été appliquée à la quantification des composés majoritaires de diverses huiles essentielles et elle est susceptible d être utilisée pour l analyse d un grand nombre d échantillons (dosage en routine des constituants caractéristiques) et permettre ainsi de répondre aux exigences de contrôle de qualité concernant ce type de produits naturels voire des exsudats et des extraits végétaux.Natural products isolated from plants acquired, in recent years, a growing success in many industries (pharmacy, agri-food, perfume and cosmetics). The objective of our study was to contribute, on the one hand, to the development of methods involving 13C and 1H NMR for the identification and quantification of the components of natural mixtures, and on the other hand, to the chemical characterization of plants growing in Corsica for their potential valorization. The first part of our work concerned the chemical characterization of the wood oil of Cedrus atlantica Manetti, introduced forty years ago and now growing wild in various Corsican forests. Detailed analysis, using the combination of chromatographic and spectroscopic techniques, of a wood oil sample allowed the identification of various compounds bearing the himachalane or bisabolane skeletons, which were still unreferenced in our home-made NMR spectral data library: (E)- -atlantone, (Z)- -atlantone, himachalol and allohimachalol. In addition, the analysis of 48 samples obtained from trees located in five forests referenced by the Office National des Forêts of Corsica (Bavella, Bonifato, Ospedale, Pineta and Vizzavona) as well as in a few isolated locations, associated with statistical treatment of the results (PCA, k-means and hierarchical clustering), suggested the occurrence of a chemical variability within the investigated samples. Samples are divided into two groups, whom chemical compositions were rarely described in the literature, based on their high contents in -pinene (Group I) or himachalol (Group II).Our second objective was to contribute to the development of an analytical method, based on 13C NMR, for identification and quantification of taxanes in natural mixtures. To reach this goal, we have first implemented two protocols of fractionation of methanol and ethanol extracts of leaves of yew (Taxus baccata L.). Eleven taxane derivatives, including five compounds not yet referenced in our home-made NMR spectral data library (deacetyltaxine B, 5-cinnamoyltaxicine I, 2,9-deacetyltaxinine, 3,11-cyclotaxinine NN2 and 2-deacetyltaxinine J) have been identified. Then, we have developed and validated a method for quantification of taxanes by 13C NMR using 10-DAB-III as model compound and hexane-1,6-diol as internal standard. The experimental procedure was applied to the quantification of the previously identified taxanes present in the extracts of T. baccata. This method can be extrapolated to other compounds bearing the taxane skeleton. In the last part of this work, we developed a method that allows direct quantitative determination of terpenes in natural mixtures, using 1H NMR. The quantitative procedure was checked and validated (accuracy, linearity and precision of measurements) with 39 commercially available terpenes of different chemical families (olefins, alcohols, ketones, aldehydes, esters, oxides, phenylpropanoids and a nitrogen-containing compound). This method is proved to be reliable, fast and complementary with GC. It may be used for the analysis of a large number of samples (routine determination of characteristic constituents) and for quality control of essential oils and solvent extracts.CORTE-BU (200962101) / SudocSudocFranceF

New Metabolites Isolated from a Laurencia obtusa Population Collected in Corsica

The chemical investigation of an ethyl acetate extract (EtOAc) obtained from Laurencia obtusa, collected in Corsica, allowed for the identification of three new compounds (1, 2, and 4) and six known compounds. Compounds 1 to 4 were isolated and fully characterized by a detailed spectroscopic analysis. Compounds 1 and 2 are two C15-acetogenins sharing the same ring system: a tetrahydropyran linked by a methylene to a tetrahydrofuran ring. Compound 1 exhibits a bromoallene unit whereas compound 2 possesses an uncommon α-bromo-α,β-unsaturated aldehyde terminal unit. Compound 4 is the first diterpene exhibiting a 19(4 → 3)abeo-labdane skeleton isolated from a Laurencia species. Isolation of concinndiol (compound 3) together with compound 4 suggests a common biosynthetic origin. Additionally, five known compounds, namely sagonenyne, laurene, α-bromocuparene, microcladallene A, and β-snyderol were identified in chromatographic fractions by NMR analysis using a computerized method that was developed in our laboratory

Identification and Quantitation of Ursolic and Oleanolic Acids in Ilex aquifolium L. Leaf Extracts Using 13C and 1H-NMR Spectroscopy

Leaves of Ilex aquifolium L. have been used for their therapeutic properties. In previous studies, components contained in the leaves were first isolated by various chromatographic techniques. Then, quantitation of oleanolic and ursolic acids, which are responsible for the biological and therapeutic activities of the plant, was performed by HPLC, HPTLC, and somewhat by GC-MS. Our objective was to develop a simple method that allows the identification of compounds contained in the leaves of Corsican I. aquifolium and to quantify ursolic and oleanolic acids. Leaves were successively extracted with hexane and dichloromethane. The extracts were chromatographed on silica gel and the fractions of column chromatography submitted to 13C-NMR analysis, following a computerized method developed in the laboratory. 13C-NMR allowed the identification of various triterpenes including ursolic acid and oleanolic acid. Quantitation of both acids was achieved, for the first time, by 1H-NMR after validation of the method (accuracy, precision, linearity, limit of detection and limit of quantitation). Ursolic and oleanolic acids accounted for 55.3% and 20.8% of the dichloromethane extract, respectively. This represents 1.3% and 0.5% of the mass of dried leaves. 1H-NMR spectroscopy appeared as a powerful tool for a rapid quantitation of biologically active compounds from I. aquifolium

Chemical Composition and Variability of Leaf and Berry oils from Corsican Juniperus macrocarpa

International audienc

Snyderol derivatives from Laurencia obtusa collected in Corsica

International audienc

Composition and Chemical Variability of Needle and Berry Oilsfrom Corsican Juniperus communis var. communis

International audienceJuniperus communis L. var. communis is widespread in European countries. In Corsica a very small population grows wild in the North-Eastern side of theisland. The chemical compositions of nine needle oil samples and three berry oil samples from Corsican J. communis L. var. communis have been investigatedby GC(RI), GC-MS and 13C NMR. The composition of needle oils was dominated by monoterpene hydrocarbons, -pinene (2/9 oil samples, 70.4 and 67.1%)or sabinene (7/9 oil samples, 24.4-45.3%). Berry oils displayed -pinene/myrcene (43.0/24.1%) or -pinene/sabinene/limonene/terpinen-4-ol(19.9/17.3/14.0/13.8%) as main components. A third oil sample contained mainly -pinene (22.0%) accompanied by 21 sesquiterpenes (42.0% in total). It isnoticeable that various needle and berry oil compositions have been observed within a really small population of J. communis L. var. communis

Composition and Chemical Variability of Corsican Pinus halepensis Cone Oil

International audienceThe composition of the essential oil isolated from cones of Pinus halepensis grown in Corsica has been investigated by a combination of chromatographic (CC, GC) and spectroscopic (MS, 13C NMR) techniques. In total, 48 compounds that accounted for 95.5% of the whole composition have been identified. a-Pinene (47.5%) was the major component followed by myrcene (11.0%), (E)-b-caryophyllene (8.3%) and caryophyllene oxide (5.9%). Various diterpenes have been identified by 13C NMR in the fractions of CC. Fifteen oil samples isolated from cones harvested in three forests have been analyzed and two groups of similar importance have been differentiated within the 15 compositions. Oil samples of the first group contained a-pinene (mean 45.0 g/100 g, SD = 5.5) as the major component. The composition of samples of the second group was dominated by myrcene (mean 30.3 g/100g, SD = 9.0) and a-pinene (mean 24.6 g/100 g, SD= 3.1)