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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
401

Kinetika i modelovanje ekstrakcije ulja iz bobica kleke (Juniperus communis L.) i semenki tikve (Cucurbita pepo L.) natkritičnim ugljendioksidom / Kinetics and mathematical modeling of juniper berry (Juniperus communis L.) essential oil and pumpkin seed (Cucurbita pepo L.) oil by supercritical carbondioxide

Nikolovski Branislava 18 December 2009 (has links)
<p>U radu su prikazani eksperimentalni rezultati natkritične ekstrakcije etarskog ulja bobica<br />kleke (<em>Juniperus communis</em> L.) i ulja iz semena uljane tikve golice (<em>Cucurbita pepo</em> L.). Ispitan je uticaj pritiska, temperature, stepena usitnjenosti čestica i protoka natkritičnog<br />ugljendioksida na promenu prinosa ulja sa vremenom. U cilju poređenja, usitnjeno seme uljane tikve ekstrahovano je i u ekstraktoru većih dimenzija, NOVA-SWISS, High<br />pressure extraction plant, kao i heksanom i petroletrom u ekstraktoru tipa Sokslet.<br />Praćena je i promena kvaliteta ekstrakata sa vremenom: u etarskom ulju kleke, GC-FID i GC-MS metodama, određen je relativni sadržaj 50 terpenskih jedinjenja i sve komponente ulja su svrstane u 5 osnovnih grupa (monoterpene, seskviterpene, oksidovane monoterpene, oksidovane seskviterpene i ostale komponente). U tikvinom ulju ekstrahovanom natkritičnim ugljendioksidom određen je masnokiselinski sastav GC-MS analizom, sadržaj tokoferola HPLC analizom, sterola i skvalena GC-MS metodom. Određeni su uslovi koji favorizuju ekstrakciju ispitanih jedinjenja za obe sirovine. Dat je dateljan prikaz matematičkih modela koji se koriste za opisivanje natkritične ekstrakcije etarskih ulja i masnih ulja, počev&scaron;i od najop&scaron;tijeg modela koji uključuje diferencijalne bilanse mase za rastvorak u masi natkritičnog fluida, u fluidu unutar pora čestica usitnjenog matrijala i u čvrstoj fazi, koji se uvođenjem određenih pretpostavki pojednostavljuje i svodi na modele koji su izabrani da budu ispitani u okviru ovoga rada. Ispitani su modeli kreireni po analogiji sa hlađenjem vrele kugle u masi fluida, tj. modeli tipa jedne sfere i to: Model jedne sfere-1 (MJS-1), koji pored uticaja koeficijenta efektivne difuzije ulja u materijalu na brzinu prenosa mase uzima u obzir uticaj koeficijenta prenosa mase kroz film natkritičnog fluida oko čestice, pri čemu je njegova vrednost procenjena preko postojećih korelacija; MJS-1 (2 par), u kome je spolja&scaron;nji koeficijent prenosa mase uzet kao drugi prilagodljiv parametar modela; MJS-2, gde je koeficijent efektivne difuzije jedini prilagođeni parametar, Model karakterističnog vremena i pro&scaron;ireni model klipnog toka koji je predložila Sovov&aacute;. Za modelovanje natkritične ekstrakcije ulja semena tikve kori&scaron;ćen je i kombinovani model Honga i sar. Softverskim paketima Mathcad 2001 Professional i Solver dodatka unutar Microsoft Excel 2003, određeni su parametri ispitanih modela u cilju najboljeg slaganja modela sa ekperimentalnim podacima. Za obe ispitane sirovine, među ispitanim modelima, izabrani su modeli koji najbolje opisuju njihovu ekstrakciju natkritičnim ugljendioksidom. Pro&scaron;ireni model klipnog toka koji je predložila Sovov&aacute; pokazao se podjednako dobrim za modelovanje natkritične ekstrakcije obe sirovine i ne&scaron;to bolji od ostalih primenjenih modela.</p> / <p>This study provides results of supercritical carbon dioxide (SCCO<sub>2</sub>) extraction of juniper berries (<em>Juniperus communis</em> L.) and pumpkin seeds (<em>Cucurbita pepo</em> L. convar.&nbsp;<em>citrullina</em>) in a laboratorysupercritical fluid extraction apparatus. The influence<br />of pressure, temperature, particle size and carbon dioxide flow on the extraction kinetics of pumpkin seed oil and juniper berry essential oil was studied. Ground pumpkin seeds were also extracted with supercritical carbon dioxide in NOVA-SWISS, High Pressure Extraction Plant, and with hexane and petroleum ether in a laboratory Soxhlet extractor. This work was also aimed to investigate the evolution of the composition of juniper fruit supercritical CO<sub>2</sub> extracts with time, at different extraction pressures and to emphasize the most favorable condition for the extraction of different terpene hydrocarbon groups, reporting the qualitative differences among extracts collected during successive extraction time periods. Juniper berry extracts were analyzed by capillary gas chromatography, using flame ionization (GC-FID) and mass spectrometric detection (GC-MS). More than 200 constituents were detected in the extracts and the contents of 50 compounds were reported in the work. Dependence of the percentage yields of monoterpene, sesquiterpene, oxygenated monoterpene and oxygenated sesquiterpene hydrocarbon groups on extraction time was investigated and conditions that favored the yielding of each terpene groups were emphasized. GC-MS analysis of FAME, prepared by transesterification of pumpkin seed oil with KOH in methanol, was performed. Fatty acid compositions of supercritical CO<sub>2</sub> pumpkin seed extract fractions collected in successive time intervals over the course of the extraction were determined. The same fractions were analyzed by high pressure liquid chromatography (HPLC), using diode-array detector (DAD) in order to determine a- and g-tocopherol contents. Sterol and squalene contents were determined by GC-MS analysis, as well. Conditions that favored the yielding of tocopherols, squalene and sterols were emphasized. A general mass transfer model and its simlifications were analysed. Extraction curves were evaluated by &ldquo;hot sphere&rdquo; mathematical models SSM-1 (Single Sphere Model 1 &ndash; in which the external mass transfer coefficient also influences the extraction profile and film mass transfer coefficients were estimated by the correlations), SSM-1 (2 par) (film mass transfer coefficient is used as the second adjustable parameter), SSM-2 (only effective diffusivity influence is considered), Characteristic time model and by the extended Lack&rsquo;s plug-flow model given by Sovov&aacute;. A combined model of Hong et al. was also fitted to the experimental data for pumpkin seed oil SCCO<sub>2&nbsp;</sub>extractions. Relative merits of the models are demonstrated. Good agreement between the extended Lack&rsquo;s plug-flow model and the experimental measurements was obtained.</p>
402

Antimicrobial and Anticancer Activity of Essential Oils from Guatemalan Medicinal Plants

Miller, Andrew B. 19 November 2010 (has links) (PDF)
Guatemalan medicinal plants were collected and screened for the presence of essential oils using steam distillation. Oil was found in 63 species from 24 families and was tested in tube dilution assays for activity against Escherichia coli, Staphylococcus aureus, Streptococcus mutans, Lactobacillus acidophilus and Candida albicans. Several essential oils were highly active with 20 instances of oils inhibiting the microbes at an MIC of 0.31 µl/ml. Oils were also tested against cancerous and established cell lines using a 15% (v/v) agar-media which was developed to improve essential oil solubility. Assays were performed against three cancer lines: Stomach (AGS: CRL-1739), Skin (A375: CRL-1619), Tongue (CAL27: CRL-2095) and an established Monkey Kidney cell line (Vero C 1008: CRL-1586). Assessment of viability was performed using the Neutral Red assay with results indicating that many of the oils significantly inhibited cancer cell lines in vitro with 24 individual instances producing an IC50 of 0.20 µl/ml or less. Therapeutic indices indicated that many of the highly inhibitory oils were more cytotoxic to cancerous cell lines than to the established cell line.
403

Funcionalización de textiles mediante encapsulación por electrohilatura

Mínguez García, David 15 February 2024 (has links)
Tesis por compendio / [ES] Esta memoria de tesis presenta una contribución al estudio de la funcionalización de sustratos textiles mediante la encapsulación de diferentes compuestos empleando la técnica del electrohilado. La variabilidad de la electrohilatura, tanto a nivel del equipo empleado como del propio proceso de electrohilado, permite la posibilidad de obtener morfologías y composiciones de nanofibras completamente distintas. En este trabajo se han abordado dos técnicas de preparación de la solución polimérica a emplear durante el proceso, los métodos de emulsión y dispersión. Ambas técnicas han posibilitado la adición de varios compuestos que han aportados nuevas características a nanofibras de PVA electrohiladas. Tras analizar los resultados obtenidos de las nanofibras extruidas a partir de la solución por emulsión, se ha demostrado la capacidad de encapsular aceites esenciales, tomillo y salvia, mediante electrohilatura. La caracterización realizada a los velos nanofibrosos demuestran la aparición de microcápsulas a lo largo de la sección longitudinal de las fibras debido a la encapsulación del aceite en su interior. Por otro lado, el método de dispersión ha sido evaluado mediante la adición de cúrcuma, compuesto no soluble en agua, a una solución de PVA. Los datos resultantes de las caracterizaciones han evidenciado la capacidad de la cúrcuma de actuar como sensor halocrómico aún estando encapsulada en el interior de las nanofibras electrohiladas. Al mismo tiempo, se ha examinado si esta capacidad halocrómica se mantiene cuando las nanofibras de PVA, que inicialmente son solubles en agua, se someten a un proceso de reticulación con ácido cítrico para su insolubilización. Los resultados han demostrado la continuidad del halocromismo, aunque difiere en la tonalidad del color resultante. Finalmente, se concluye con una comparativa por adición de materia colorante mediante los dos métodos explicados a una solución polimérica. Los velos nanofibrosos fabricados a partir de la solución dispersada presentaban una notable coloración en su superficie, mientras que las nanofibras producidas a partir de la solución por emulsión no presentaban color, lo cual vuelve a justificar la encapsulación del aceite coloreado en el interior de la nanofibra. / [CA] Aquesta memòria de tesi presenta una contribució a l'estudi de la funcionalització de substrats tèxtils mitjançant l'encapsulació de diferents compostos emprant la tècnica de l'electrofilat. La variabilitat de l'electrofilatura, tant a nivell de l'equip emprat com del procés d'electrofilat propi, permet la possibilitat d'obtenir morfologies i composicions de nanofibres completament diferents. En aquest treball s'han abordat dues tècniques de preparació de la solució polimèrica a emprar durant el procés, els mètodes d'emulsió i de dispersió. Ambdues tècniques han possibilitat l'addició de diversos compostos que han aportat noves característiques a nanofibres de PVA electrofilades. Després d'analitzar els resultats obtinguts de les nanofibres extruïdes a partir de la solució per emulsió, s'ha demostrat la capacitat d'encapsular olis essencials, farigola i sàlvia, mitjançant electrofil·latura. La caracterització realitzada a les estores nanofibroses demostren l'aparició de microcàpsules al llarg de la secció longitudinal de les fibres a causa de l'encapsulació de l'oli al seu interior. D'altra banda, el mètode de dispersió s'ha avaluat mitjançant l'addició de cúrcuma, compost no soluble en aigua, a una solució de PVA. Les dades resultants de les caracteritzacions han evidenciat la capacitat de la cúrcuma d'actuar com a sensor halocròmic encara estant encapsulada a l'interior de les nanofibres electrofilades. Alhora, s'ha examinat si aquesta capacitat halocròmica es manté quan les nanofibres de PVA, que inicialment són solubles en aigua, se sotmeten a un procés de reticulació amb àcid cítric per a la seua insolubilització. Els resultats han demostrat la continuïtat de l'halocromisme encara que difereix en la tonalitat del color resultant. Finalment, es conclou amb una comparativa per addició de matèria colorant mitjançant els dos mètodes explicats a una solució polimèrica. Els vels nanofibrosos fabricats a partir de la solució dispersada presentaven una notable coloració a la superfície, mentre que les nanofibres produïdes a partir de la solució per emulsió no presentaven color, la qual cosa torna a justificar l'encapsulació de l'oli acolorit a l'interior de la nanofibra. / [EN] This thesis report presents a contribution to the study of the functionalisation of textile substrates through the encapsulation of different compounds using the electrospinning technique. The variability of electrospinning, both at the level of the equipment used and of the electrospinning process itself, allows the possibility of obtaining completely different morphologies and compositions of nanofibres. In this work, two techniques for the preparation of the polymer solution to be used during the process have been addressed, the emulsion and dispersion methods. Both techniques have allowed the addition of several compounds that have provided new properties to electrospun PVA nanofibres. After analysing the results obtained from the nanofibres extruded from the emulsion solution, the ability to encapsulate essential oils, thyme and sage, by electrospinning was demonstrated. The characterisation of the nanofibrous mats shows the appearance of microcapsules along the longitudinal section of the fibres, due to the encapsulation of the oil inside them. On the other hand, the dispersion method was evaluated by adding turmeric, a non-water soluble compound, to a PVA solution. The data obtained from the characterisations have showed the ability of turmeric to act as a halochromic sensor even when encapsulated in the electrospun nanofibres. At the same time, it was investigaed whether this halochromic capacity is maintained when the PVA nanofibres, which are initially soluble in water, undergo a cross-linking process with citric acid to insolubilise them. The results have shown the continuity of the halochromism, although the resulting shade is different. Finally, we compare the addition of dyes to a polymer solution using the two methods described above. The nanofibrous veils produced from the dispersed solution showed a noticeable colouration on their surface, whereas the nanofibres produced from the emulsion solution were colourless, which again justifies the encapsulation of the coloured oil inside the nanofibre. / Mínguez García, D. (2024). Funcionalización de textiles mediante encapsulación por electrohilatura [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/202719 / Compendio
404

Estudo quÃmico de asterÃceas do CearÃ: Baccharis trinervis, Eupatorium ballotaefolium, Eupatorium betonicaeforme, Eupatorium pauciflorum, Pectis apodocephala, Pectis oligocephala, Verbesina diversifolia, Vernonia chalybaea e Vernonia scorpioides / Chemical investigations of asterÃceas of CearÃ: Baccharis trinervis, Eupatorium ballotaefolium, Eupatorium betonicaeforme, Eupatorium pauciflorum, Pectis apodocephala, Pectis oligocephala, Verbesina diversifolia, Vernonia chalybaea e Vernonia scorpioides

Maria Rose Jane Ribeiro Albuquerque 29 August 2006 (has links)
CoordenaÃÃo de AperfeiÃoamento de Pessoal de NÃvel Superior / Este trabalho descreve a investigaÃÃo quÃmica de plantas da famÃlia Asteraceae nativas da flora cearense, pertencentes aos gÃneros Baccharis, Eupatorium, Pectis, Verbesina e Vernonia. Eupatorium ballotaefolium H.B.K. e E. betonicaeforme Baker foram selecionados para o estudo da composiÃÃo quÃmica volÃtil e nÃo-volÃtil, enquanto Baccharis trinervis (Lam.) Pers., E. pauciflorum Kunth, Pectis apodocephala Baker, P. oligocephala Baker, Verbesina diversifolia D.C., Vernonia chalybaea Mart. e V. scorpioides (Lam.) Pers, tiveram exclusivamente a composiÃÃo quÃmica dos Ãleos essenciais determinados. O potencial antimicrobiano, larvicida e nematicida de alguns Ãleos foi avaliado. O Ãleo essencial de B. trinervis apresentou moderada atividade antimicrobiana, enquanto os Ãleos essenciais de P. apodocephala, P. oligocephala e E. betonicaeforme, incluindo dois de seus principais constituintes, 2,2-dimetil-6-vinilcroman-4-ona e 2-senecioil-4-vinilfenol, apresentaram significativa atividade larvicida contra larvas do Aedes aegypti. Os Ãleos essenciais das Pectis acima mencionadas, tambÃm apresentaram propriedades nematicida contra o fito-nematÃide Meloidogyne incognita. Neste trabalho investigou-se ainda, a composiÃÃo dos Ãcidos graxos contidos nas fraÃÃes apolares dos extratos hexÃnicos da parte aÃrea de E. ballotaefolium e E. betonicaeforme. Foram identificados um total de 13 Ãcidos graxos, sendo o Ãcido hexadecanÃico (C16:0) o constituinte majoritÃrio para ambas as espÃcies. A prospecÃÃo quÃmica relativa Ãs duas espÃcies de Eupatorium resultou no isolamento e identificaÃÃo de 11 substÃncias para E. ballotaefolium e 17 substÃncias para E. betonicaeforme. Do extrato hexÃnico da parte aÃrea de E. ballotaefolium isolou-se, em mistura, os fitoesterÃides &#946;- sitosterol e estigmasterol e os triterpenos acetato de taraxasterila e taraxasterol, enquanto do extrato etanÃlico, foram isolados e caracterizados os flavonÃides nepetina e quercetina na forma glicosilada e as formas glicosÃdicas do sitostetol e estigmasterol. Do extrato hexÃnico das raÃzes foram isolados os triterpenos epifriedelanol e dammara-20,24-dien-3&#946;-ol e do extrato etanÃlico foi obtida a cumarina 11-hidroxi-11,12-di-hidroobliquina. Do extrato hexÃnico das flores de E. betonicaeforme foram isolados uma lactona sesquiterpÃnica, 8&#946;- angeloiloxi-9&#946;,10&#946;-di-hidroxi-1-oxo-germacra-4E,11(13)dien-12,6&#945;-olido, uma lactona de cadeia longa, 3&#946;-hidroxieicosan-1,5&#946;-olido, os diterpenos Ãcido grandiflÃrico e Ãcido 15&#945;- decanoiloxi-caur-16-en-19-Ãico, o esterÃide espinasterol e o Ãcido hexacosanÃico, enquanto do extrato etanÃlico, foram isolados o triterpeno acetato de taraxasterila e os flavonÃides, nepetina, canferol e ramnocitrina. Do extrato hexÃnico das raÃzes, isolou-se em mistura, os xxiv esterÃides &#946;-sitosterol e estigmasterol, enquanto do extrato etanÃlico isolou-se a cromona 6,6- acetil-2,2-dimetilcroman-4-ona e o flavonÃide nepetina. Do extrato hexÃnico da parte aÃrea isolou-se a mistura binÃria dos triterpenos &#945;- e &#946;-amirina, alÃm do acetato de taraxasterila. De acordo com o levantamento bibliogrÃfico, o diterpeno denominado Ãcido 15&#945;-decanoiloxicaur- 16-en-19-Ãico, ainda nÃo havia sido registrado na literatura e os constituintes 8&#946;- angeloiloxi-9&#946;,10&#946;-di-hidroxi-1-oxo-germacra-4E,11(13)dien-12,6&#945;-olido, 3&#946;- hidroxieicosan-1,5&#946;-olido, 2,2-dimetil-6-vinil-croman-4-ona, 6-acetil -2,2-dimetil-croman-4- ona, 2-senecioil-4-vinilfenol e damara-20,24-dien-3&#946;-ol, estÃo sendo registrados pela primeira vez no gÃnero. A lactona 8&#946;-angeloiloxi-9&#946;,10&#946;-di-hidroxi-1-oxo-germacra-4E,11(13)dien- 12,6&#945;-olido e o flavonÃide nepetina apresentaram moderado potencial citotÃxico quando testados frente a um painel de cÃlulas tumorais, apresentando IC50 nas faixas de 1,27-7,16 e 5,48-15,12 &#956;g/mL, respectivamente. A determinaÃÃo estrutural dos metabÃlitos secundÃrios isolados neste trabalho envolveu o uso de tÃcnicas espectromÃtricas como infravermelho (IV), espectrometria de massa (EM) e ressonÃncia magnÃtica nuclear de hidrogÃnio (RMN 1H) e carbono-13 (RMN 13C), incluindo tÃcnicas bidimensionais como COSY, HMQC, HMBC e NOESY, bem como comparaÃÃo com dados descritos na literatura. / This work describes the chemical investigation of native plants of the Asteraceae family from Cearà State flora, belonging to the genera Baccharis, Eupatorium, Pectis, Verbesina and Vernonia. Eupatorium ballotaefolium H.B.K. and E. betonicaeforme Baker were selected to study their volatile and non-volatile chemical composition, while for Baccharis trinervis (Lam.) Pers., E. pauciflorum Kunth, Pectis apodocephala Baker, P. oligocephala Baker, Verbesina diversifolia D.C., Vernonia chalybaea Mart. and V. scorpioides (Lam.) Pers only the chemical composition of the essential oils, was determined. The antimicrobial, larvicidal and nematicidal potential of some of the oils were evaluated. The essential oil of B. trinervis showed moderate antimicrobial activity, while the essential oils of P. apodocephala, P. oligocephala and E. betonicaeforme, including two of their major constituents, 2,2-dimethyl-6-vinylchroman-4-one and 2-senecioyl-4-vinylphenol, showed significant larvicidal activity against the Aedes aegypti larvae. The essential oils from the above mentioned Pectis species also showed nematicidal properties against the nematode Meloidogyne incognita. The fatty acid composition of the apolar fractions from the hexane extracts of the aerial parts of E. ballotaefolium and E. betonicaeforme was also examined. A total of 13 fatty acids were identified, being hexadecanoic acid (C16:0) the major compound for both species. The chemical analysis of both Eupatorium species resulted in the isolation and characterization of 11 substances for E. ballotaefolium and 17 substances for E. betonicaeforme. From the hexane extract of the aerial parts of E. ballotaefolium was isolated a mixture of &#946;-sitosterol and stigmasterol, the triterpenes taraxasteryl acetate and taraxasterol, while the flavonoids nepetin and quercetin-3-O-glucoside and a binary misture of sitosterol and stigmasterol glucosilated, were isolated from the ethanol extract. From the hexane extract of the roots were isolated the tritepenes epifriedelanol and dammara-20,24-dien-3&#946;-ol and from the ethanol extract was obtained the coumarin 11-hydroxy-11,12-di-hydroobliquine. From the hexane extract of E. betonicaeforme flowers a sesquiterpene lactone, 8&#946;- angeloyloxy-9&#946;,10&#946;-dihydroxy-1-oxo-germacra-4E,11(13)dien-12,6&#945;-olide, a long chain lactone 3&#946;-hydroxiicosan-1,5&#946;-olide, the diterpenes grandifloric and 15&#945;-decanoyloxy-kaur- 16-en-19-oic acids, the steroid spinasterol and hexacosanoic acid were isolated. From the ethanol extract were isolated taraxasteril acetate, nepetin, kaempferol and ramnocitrin. From the hexane extract of the roots were isolated the mixture of &#946;-sitosterol and stigmasterol, while from the ethanol extract were isolated 6,6-acetyl-2,2-dimethylcroman-4-one and nepetin. The hexane extract of the aerial parts were obtained the binary mixture of &#945;- and &#946;- amyrin, and taraxasteryl acetate. To the best of our knowledge the diterpene characterized as 15&#945;-decanoyloxy-kaur-16-en-19-oic acid is a new substance while the compounds 8&#946;- angeloyloxy-9&#946;,10&#946;-dihydroxy-1-oxo-germacra-4E,11(13)dien-12,6&#945;-olide, 3&#946;- hydroxyeicosan-1,5&#946;-olide, 2,2-dimethyl-6-vinyl-chroman-4-one, 6-acetyl-2,2-dimethylchroman- 4-one, 2-senecioyl-4-vinylphenol and dammara-20,24-dien-3&#946;-ol are being reported for the first time to the genus. The lactone 8&#946;-angeloyloxy-9&#946;,10&#946;-dihydroxy-1-oxogermacra- 4E,11(13)dien-12,6&#945;-olide and the flavonoid nepetin showed moderated cytotoxic activity against a panel of five cell lines with IC50 in the range of 1,27-7,16 e 5,48-15,12 &#956;g/mL, respectively. The structures of all secondary metabolites were established using spectrometric data such as IR, MS, 1H and 13C NMR, including bidimensional techniques (COSY, HMQC, HMBC and NOESY), and comparison with from the literature data.
405

Contribution de la RMN 13C à l’analyse des huiles végétales, huiles essentielles et résines (Olea europaea, Pinus halepensis et Cedrus atlantica) / Contribution of the 13C NMR analysis of vegetable oils, essential oils and resins (Olea europaea, Pinus halepensis and Cedrus atlantica)

Nam, Anne-Marie 21 March 2014 (has links)
Les produits issus de la biomasse végétale connaissent depuis quelques années un succès grandissant dans de nombreuses industries (aromathérapie, cosmétique, parfums, etc.). 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 RMN 1H (par exemple le squalène dans l’huile d’olive), et d’autre part, de contribuer à la caractérisation chimique de deux conifères introduits en Corse, le pin d’Alep (huile essentielle) et le cèdre de l’Atlas (huile essentielle, huile pyrolytique et résine).La première partie concerne la quantification du squalène présent dans l’huile d’olive. En effet, ce triterpène linéaire participe à la stabilité oxydative de l’huile d’olive et joue un rôle important dans la réduction des risques de certains cancers. Il s’agissait de mettre au point un protocole expérimental basé sur la RMN 1H ou 13C en utilisant un appareil de routine (9,4 Tesla). La quantification par RMN 13C s’est avérée fiable et elle a été appliquée à la quantification du squalène dans 25 échantillons d’huile d’olive de Corse.La seconde partie de nos travaux concerne la caractérisation chimique de l’huile essentielle de pin d’Alep introduit dans trois stations de Corse (Capo di Feno, Saleccia et Tre Padule de Suartone). L’analyse détaillée de l’huile essentielle de cônes, par combinaison des techniques chromatographiques et spectroscopiques, a permis d’identifier 48 composés. La composition chimique est largement dominée par les monoterpènes (Alpha-pinène et myrcène) et un sesquiterpène oléfinique ((E)-Béta-caryophyllène). La RMN 13C a permis d’identifier divers diterpènes, dont le 8,12-époxy-14-labdèn-13-ol. Ce composé est décrit pour la première fois dans l’huile essentielle de pin d’Alep. L’analyse de 15 échantillons d’huile essentielle de cônes a mis en évidence trois types de compositions : Alpha-pinène ; myrcène ; Alpha-pinène/myrcène. Enfin, l’analyse de 47 échantillons d’huile essentielle d’aiguilles, associée à un traitement statistique des données (ACP, AFD), a permis de mettre en évidence une variabilité chimique intraspécifique. Ainsi, les échantillons se répartissent en trois groupes selon leur teneur en (E)-Béta-caryophyllène (groupe I), en E-Béta-caryophyllène/Alpha-pinène/myrcène (groupe II) et en myrcène (groupe III).La dernière partie a été consacrée à l’étude de Cedrus atlantica. L’analyse détaillée d’une huile essentielle commerciale (du Maroc) a permis d’identifier 20 constituants, les composés majoritaires sont les Alpha-, Béta- et Gamma-himachalène. Par ailleurs, 7 composés absents de notre bibliothèque de données spectrales ont été identifiés par RMN 13C. Les compositions chimiques des huiles pyrolytiques artisanales du Maroc sont également dominées par les himachalènes et la (E)-Alpha-atlantone. Enfin, nous avons réalisé l’analyse qualitative et quantitative par RMN 13C, sans séparation préalable, de 28 échantillons de résine de C. atlantica récoltés dans les 5 forêts de Corse référencées par l’ONF (Bavella, Bonifato, Ospedale, Pineta et Vizzavona). A côté des acides résiniques, nous avons également identifié 3 lignanes (pinorésinol, laricirésinol et 9-acétate de laricirésinol). Pour l’ensemble de ces composés, nous avons mis en évidence trois types chimiques. Enfin, nous avons mis au point et validé un protocole expérimental de quantification des lignanes par RMN 1H. / Natural products isolated from plants acquired, in recent years, a growing success in many industries (aromatherapy, cosmetic, perfumes). 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 two conifers brought to Corsica, Aleppo pine (essential oil) and atlas cedar (essential oil, pyrolysis oil and resins).The first part concerned the quantification of squalene present in olive oil. Indeed, linear triterpene participated in the oxidative stability of olive oil and play an important role by decreasing some kind of cancers risks. It’s deal with to elaborate an experimental part based on NMR 1H and 13C by using routine apparatus (9.4 Tesla). Quantification by NMR 13C is reliable and have been applied to squalene quantification in 25 samples of Corsican olive oil.The second part of our work concerned the chemical characterization of the essential oil of Aleppo pine brought to Corsica in three different stations (Capo di Feno, Saleccia and Tre Padule de Suartone). A detailed analysis of cone essential oil, using the combination of chromatographic and spectroscopic techniques, leads to the identification of 48 compounds. Chemical composition is extensively dominated by monoterpens (Alpha-pinene and myrcene) and one olefinic sesquiterpen ((E)-Béta-caryophyllene). 13C NMR allowed to the identification of various diterpens, particularly the 8,12-epoxy-14-labden-13-ol. This compound is described for the first time in aleppo pine essential oil. Fifteen samples of cone essential oil were analysed allowing differentiating three kinds of compositions: Alpha-pinene; myrcene; Alpha-pinene/myrcene. Finally, analysis of 47 samples of needles essential oil, associated with statistical treatment of the results (PCA and PFA), suggested the occurrence of an intraspecific chemical variability. Samples are divided into three groups, based on their high contents in (E)-Béta-caryophyllene (groupe I), in (E)-Béta-caryophyllene/Alpha-pinene/myrcene (groupe II) and in myrcene (groupe III).The last part concerned the study of Cedrus atlantica. A detailed analysis of commercial essential oil leads to the identification of 20 constituents. Main compounds are Alpha-, Béta- and Gamma-himachalene. Moreover, seven compounds, not yet referenced in our home-made NMR spectral data library, were identified by NMR 13C. Chemical compositions of handwork pyrolysis oils from Morocco were also dominated by the himachalene’s and (E)--atlantone. Qualitative and quantitative analysis of 28 samples of Cedrus atlantica resins, obtained from the five Corsican forests referenced by the Office National des Forêts of Corsica (Bavella, Bonifato, Ospedale, Pineta and Vizzavona) have been done, without any step of chromatography. Beside resinic acids, we have been identified three lignans (pinoresinol, lariciresinol and lariciresinol-9-acetate). Qualitative and quantitative analysis of these compounds, leads to the occurrence of three types of chemical composition. Finally, we have developed and validated a method for quantification of lignans by 1H NMR.
406

CONSTITUINTES DE Senecio heterotrichius DC.: ISOLAMENTO, ELUCIDAÇÃO ESTRUTURAL, DERIVATIZAÇÃO E AVALIAÇÃO DA ATIVIDADE ANTIMICROBIANA; ESTUDO DOS CONSTITUINTES VOLÁTEIS DE OUTRAS ESPÉCIES DE Senecio / CONSTITUENTS OF Senecio heterotrichius DC.: ISOLATION, STRUCTURAL ELUCIDATION, DERIVATIZATION AND EVALUATION OF THE ANTIMICROBIAL ACTIVITY; STUDY OF THE VOLATILE CONSTITUENTS FROM OTHER Senecio SPECIES

Francescato, Leandro Nicolodi 05 March 2007 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Genus Senecio (Asteraceae) constitutes a group of cosmopolitan plants formed by more than 2000 species. Although these plants have toxicity recognized due to the presence of pyrrolizidine alkaloids, several of them are used in folk medicine. Their medicinal use can be attributed to other secondary metabolites such as flavonoids and terpenoids, being that terpenoids are compounds with recognized antimicrobial activity. In this work, the evaluation of the antimicrobial activity of the CH2Cl2 and EtOH extracts of S. heterotrichius DC., the isolation and characterization of one constituent from CH2Cl2 extract, the reaction of photooxidation of this compound in order to obtain a peroxide as well as the chemical analysis and evaluation of the antimicrobial activity of the essential oils from Senecio heterotrichius DC., S. ceratophylloides Griseb., S. oxyphyllus DC. and S. leptolobus DC. were studied. Extracts of the fresh aerial parts of S. heterotrichius were obtained by sequential maceration at room temperature in CH2Cl2 and EtOH, followed by evaporation under reduced pressure. The CH2Cl2 extract was firstly fractioned by CC over silica gel for the isolation of the sesquiterpene germacrene D and then identified by GC-MS, 1H and 13C NMR. This compound, considered a precursor of several other sesquiterpene derivatives, was submitted to photooxidation reaction using Bengal rose as sensitizer agent. The main formed peroxide was isolated from the reactional mixture by CC over silica gel, analyzed by GC-MS,1H and 13C NMR, and identified as being germacrene-D-1-hydroperoxide. The evaluation of the antimicrobial activity of the extracts of S. heterotrichius and of germacrene-D-1-hydroperoxide was accomplished through the broth microdilution method based on M27- A2/NCCLS documents for yeasts and M7-A4/NCCLS for aerobic bacteria. The extraction of the essential oils of the flowery aerial parts of Senecio heterotrichius, S. ceratophylloides, S. oxyphyllus and S. leptolobus was accomplished through hydrodestilation. The obtained essential oils were analyzed by GC-MS and their constituents were identified by the comparison of their Kovat s Indexes and their fragmentation patterns with literature data. These oils also had their antimicrobial activity evaluated following the previously mentioned methodology. The CH2Cl2 extract evidenced inhibitory activity against Candida krusei (MIC of 0.25 mg/mL) and Staphylococcus aureus (MIC of 2.5 mg/mL). The EtOH extract was inactive against the tested microorganisms. The germacrene-D-1-hydroperoxide presented inhibitory activity against S. cerevisiae (MIC of 2.5 mg/mL), and inhibited partially the growth of the algae Prototheca zoopfi at 5 and 2.5 mg/mL (inhibition of 80 and 50%, respectively). The essential oils of S. ceratophylloides and S. leptolobus exhibited inhibitory and bactericidal activity against Staphylococcus aureus and Pseudomonas aeruginosa (MIC and MBC between 6.6 and 3.3 mg/mL). The oil of S. oxyphyllus just inhibited partially the growth of these microorganisms (MIC 50% = 6.6 and 1.6 mg/mL, respectively). The oil of S. heterotrichius inhibited partially the growth of S. aureus with a MIC 50% = 3.3 mg/mL. These oils are constituted almost exclusively by mono and sesquiterpenoids, being germacrene D one of the main constituents present in all essential oils. / O gênero Senecio (Asteraceae) constitui um grupo de plantas cosmopolitas formado por mais de 2000 espécies. Embora estas tenham toxicidade reconhecida devido à presença de alcalóides pirrolizidínicos, várias delas são empregadas na medicina popular. Seu uso medicinal pode ser atribuído aos demais metabólitos secundários, entre eles flavonóides e terpenóides, sendo estes últimos, compostos com reconhecida atividade antimicrobiana. Neste estudo é relatada a avaliação da atividade antimicrobiana dos extratos CH2Cl2 e EtOH de S. heterotrichius DC., o isolamento e caracterização de um constituinte do extrato CH2Cl2, a reação de fotooxidação deste constituinte obtendo-se um peróxido, bem como a análise química e avaliação da atividade antimicrobiana dos óleos essenciais de Senecio heterotrichius DC., S. ceratophylloides Griseb., S. oxyphyllus DC. e S. leptolobus DC. Os extratos das partes aéreas frescas de S. heterotrichius foram obtidos por maceração seqüencial à temperatura ambiente em CH2Cl2 e EtOH, seguido de evaporação sob pressão reduzida. O extrato CH2Cl2 foi fracionado por CC sobre gel de sílica até o isolamento do germacreno D, identificado por CG-EM, RMN 13C e 1H. Este composto, considerado um precursor de vários outros derivados de esqueleto sesquiterpênico, foi submetido a uma reação de foto-oxidação utilizando o corante Rosa de Bengala como agente sensibilizante; o principal peróxido formado foi isolado da mistura reacional por CC sobre gel de sílica, analisado por CG-EM, RMN 13C e 1H, e identificado como sendo o germacreno-D-1-hidroperóxido. A avaliação de atividade antimicrobiana dos extratos de S. heterotrichius e do germacreno-D-1-hidroperóxido foi realizada através do método de microdiluição em caldo, baseado nos documentos M27-A2/NCCLS para fungos leveduriformes e M7-A4/NCCLS para bactérias aeróbias. A extração dos óleos essenciais das partes aéreas floridas de Senecio heterotrichius, S. ceratophylloides, S. oxyphyllus e S. leptolobus foi realizada pela técnica de hidrodestilação. Os óleos essenciais obtidos foram analisados por CG-EM e seus constituintes foram identificados através da comparação de seus Índices de Kovat s e dos modelos de fragmentação com dados da literatura. Estes óleos também tiveram sua atividade antimicrobiana avaliada conforme metodologia citada anteriormente. O extrato CH2Cl2 evidenciou atividade inibitória frente Candida krusei (CIM de 0,25 mg/mL) e Staphylococcus aureus (CIM de 2,5 mg/mL). Já o extrato EtOH foi inativo frente os microrganismos testados. O germacreno-D-1-hidroperóxido apresentou atividade inibitória frente S. cerevisiae (CIM de 2,5 mg/mL) e inibiu parcialmente o crescimento da alga Prototheca zoopfi nas concentrações de 5 e 2,5 mg/mL (80 e 50 % de inibição, respectivamente). Os óleos essenciais de S. ceratophylloides e S. leptolobus apresentaram atividade inibitória e bactericida frente Staphylococcus aureus e Pseudomonas aeruginosa (CIM e CBM entre 6,6 e 3,3 mg/mL); o óleo de S. oxyphyllus apenas inibiu parcialmente o crescimento destes microrganismos (CIM 50% = 6,6 e 1,6 mg/mL, respectivamente); já o óleo de S. heterotrichius inibiu parcialmente o crescimento de S. aureus com uma CIM 50% = 3,3 mg/mL. Estes óleos são constituídos quase que exclusivamente de mono e sesquiterpenóides, sendo o germacreno D um dos constituintes majoritários presentes em todos os óleos essenciais.
407

Época de colheita, irrigação, fitoquímica e atividades carrapaticida e fungicida do óleo essencial de genótipos de Lippia gracilis Schauer

Cruz, Elizangela Mércia de Oliveira 15 March 2013 (has links)
The aim of this study was to determine the influence of harvesting time and water stress on the chemical composition of the essential oil and to test the activities against ticks and fungus of the essential oil of L. gracilis. For the analysis of harvest season the plant material was collected from seven genotypes of L. gracilis at the Research Farm "Campus Rural da UFS", in the rainy and dry seasons. The experiment testing water stress was conducted in the dry season. The extraction of essential oils was performed in the Laboratory of Phytotechnology of the UFS through hydrodistillation. Chemical analysis of the essential oil performed using GC-MS in the Laboratory of Chromatography of the UFS. For the activity tests against ticks package larvae and immersion of engorged tick Rhipicephalus microplus in different concentrations of essential oil, thymol or carvacrol. To test of fungicidal activity, the essential oil at different concentrations was added to PDA medium. Each plate was inoculated with mycelia culture of Thielaviopis paradoxa. The essential oil of L. gracilis presented two distinct chemotypes, one genotype LGRA-106 presenting as major compound thymol and the other genotypes presenting carvacrol as major compound. The leaves provided essential oil with an average grade of 1.55% in the rainy season and 2.09% in the dry season. In the rainy season there was no significant difference in both the yield and the content. The chemical composition of essential oils L. gracilis showed high levels of terpenes, 92% in the rainy season and 96% in the dry season. In the experiment with irrigation the values of content and yield of all genotypes were smaller when compared without irrigation. In general, the species L. gracilis, for the presence of water in the soil, provides stability in the chemical composition of the essential oil regardless of season, since plants subjected to irrigation, even in the dry season, the essential oil produced in quantity and quality similar to the rainy season. The essential oil of L. gracilis exhibits high activity against ticks, proven by lethal concentrations of genotypes LGRA-201 (1.31 mg.mL-1) and LGRA-106 (4.66 mg.mL-1), demonstrating efficiency in the control of this parasite. The tests showed that the concentrations 0.45; 0.91 and 2.75 mg.mL-1 of all genotypes of L. gracilis completely inhibited the development of the pathogen T. paradoxa, corresponding to a percentage of mycelium growth inhibition of 100%. The concentration of 0.18 mg.mL-1 of essential oil was sufficient to significantly reduce the number of spores of T. paradoxa. The minimal fungicidal concentration T. paradoxa was found between concentrations from 0.80 to 0.98 mg.mL-1 for the essential oils and 0.26 mg.mL-1 for carvacrol and 0.35 mg.mL-1 to thymol. / O presente trabalho teve como objetivo determinar a influencia da época de colheita e do estresse hídrico na composição química do óleo essencial e testar a atividade carrapaticida e fungicida do óleo essencial de L. gracilis. Para as análises de época de colheita o material vegetal foi colhido de sete genótipos de L. gracilis no Campus Rural da UFS , nas épocas chuvosa e seca. Já para o ensaio de estresse hídrico o experimento foi conduzido na época seca. A extração de óleos essenciais foi realizada no Laboratório de Fitotecnia da UFS, por meio de hidrodestilação. A análise química do óleo essencial foi realizada utilizando CG-EM, no Laboratório de Cromatografia da UFS. Para a atividade carrapaticida foram realizadas os testes de pacote de larvas e de imersão de fêmeas ingurgitadas do carrapato Rhipicephalus microplus em diversas concentrações de óleo essencial, timol ou carvacrol. Para o teste de atividade fungicida, o óleo essencial, em diferentes concentrações foi adicionado ao meio BDA. Cada placa foi inoculada com micélios da cultura monospórica de Thielaviopis paradoxa. O óleo essencial de L. gracilis apresentou dois quimiotipos distintos um com o genótipo LGRA-106 apresentando o composto timol como majoritário e os demais o carvacrol. As folhas forneceram óleos essenciais amarelados com teor médio de 1,55% na época chuvosa e 2,09% na seca. Na época chuvosa não houve diferença significativa tanto no rendimento como no teor. A composição química dos óleos essenciais de L. gracilis apresentou altos níveis de terpenos, 92% na época chuvosa e 96% na época seca. No ensaio com irrigação os valores de teor e rendimento de todos os genótipos são menores quando comparado com o ensaio sem irrigação. De maneira geral a espécie L. gracilis, quanto à presença de água no solo, apresenta estabilidade na composição química do óleo essencial independente da época do ano, uma vez que as plantas submetidas à irrigação, mesmo no verão, produziram óleo essencial em quantidade e qualidade semelhantes à época do inverno. O óleo essencial de L. gracilis apresenta alta atividade carrapaticida, comprovados pelas concentrações letais dos genótipos LGRA-201 (1,31 mg.mL-1) e LGRA-106 (4,66 mg.mL-1), demonstrando eficiência no controle desse parasita. Os ensaios demonstraram que as concentrações 0,45; 0,91 e 2,75mg.mL-1 de todos os genótipos de L. gracilis inibiram completamente o desenvolvimento do patógeno T. paradoxa, correspondendo a uma porcentagem de inibição do crescimento micelial de 100%. A concentração de 0,18mg.mL-1 de óleo essencial foi suficiente para reduzir significativamente o número de esporos de T. paradoxa. A concentração fungicida mínima de T. paradoxa foi encontrada entre as concentrações de 0,80 a 0,98mg.mL-1 para os óleos essenciais e 0,26mg.mL-1 para o carvacrol, e 0,35mg.mL-1 para o timol.
408

Época de colheita, irrigação, fitoquímica e atividades carrapaticida e fungicida do óleo essencial de genótipos de Lippia gracilis Schauer

Cruz, Elizangela Mércia de Oliveira 15 March 2013 (has links)
The aim of this study was to determine the influence of harvesting time and water stress on the chemical composition of the essential oil and to test the activities against ticks and fungus of the essential oil of L. gracilis. For the analysis of harvest season the plant material was collected from seven genotypes of L. gracilis at the Research Farm "Campus Rural da UFS", in the rainy and dry seasons. The experiment testing water stress was conducted in the dry season. The extraction of essential oils was performed in the Laboratory of Phytotechnology of the UFS through hydrodistillation. Chemical analysis of the essential oil performed using GC-MS in the Laboratory of Chromatography of the UFS. For the activity tests against ticks package larvae and immersion of engorged tick Rhipicephalus microplus in different concentrations of essential oil, thymol or carvacrol. To test of fungicidal activity, the essential oil at different concentrations was added to PDA medium. Each plate was inoculated with mycelia culture of Thielaviopis paradoxa. The essential oil of L. gracilis presented two distinct chemotypes, one genotype LGRA-106 presenting as major compound thymol and the other genotypes presenting carvacrol as major compound. The leaves provided essential oil with an average grade of 1.55% in the rainy season and 2.09% in the dry season. In the rainy season there was no significant difference in both the yield and the content. The chemical composition of essential oils L. gracilis showed high levels of terpenes, 92% in the rainy season and 96% in the dry season. In the experiment with irrigation the values of content and yield of all genotypes were smaller when compared without irrigation. In general, the species L. gracilis, for the presence of water in the soil, provides stability in the chemical composition of the essential oil regardless of season, since plants subjected to irrigation, even in the dry season, the essential oil produced in quantity and quality similar to the rainy season. The essential oil of L. gracilis exhibits high activity against ticks, proven by lethal concentrations of genotypes LGRA-201 (1.31 mg.mL-1) and LGRA-106 (4.66 mg.mL-1), demonstrating efficiency in the control of this parasite. The tests showed that the concentrations 0.45; 0.91 and 2.75 mg.mL-1 of all genotypes of L. gracilis completely inhibited the development of the pathogen T. paradoxa, corresponding to a percentage of mycelium growth inhibition of 100%. The concentration of 0.18 mg.mL-1 of essential oil was sufficient to significantly reduce the number of spores of T. paradoxa. The minimal fungicidal concentration T. paradoxa was found between concentrations from 0.80 to 0.98 mg.mL-1 for the essential oils and 0.26 mg.mL-1 for carvacrol and 0.35 mg.mL-1 to thymol. / O presente trabalho teve como objetivo determinar a influencia da época de colheita e do estresse hídrico na composição química do óleo essencial e testar a atividade carrapaticida e fungicida do óleo essencial de L. gracilis. Para as análises de época de colheita o material vegetal foi colhido de sete genótipos de L. gracilis no Campus Rural da UFS , nas épocas chuvosa e seca. Já para o ensaio de estresse hídrico o experimento foi conduzido na época seca. A extração de óleos essenciais foi realizada no Laboratório de Fitotecnia da UFS, por meio de hidrodestilação. A análise química do óleo essencial foi realizada utilizando CG-EM, no Laboratório de Cromatografia da UFS. Para a atividade carrapaticida foram realizadas os testes de pacote de larvas e de imersão de fêmeas ingurgitadas do carrapato Rhipicephalus microplus em diversas concentrações de óleo essencial, timol ou carvacrol. Para o teste de atividade fungicida, o óleo essencial, em diferentes concentrações foi adicionado ao meio BDA. Cada placa foi inoculada com micélios da cultura monospórica de Thielaviopis paradoxa. O óleo essencial de L. gracilis apresentou dois quimiotipos distintos um com o genótipo LGRA-106 apresentando o composto timol como majoritário e os demais o carvacrol. As folhas forneceram óleos essenciais amarelados com teor médio de 1,55% na época chuvosa e 2,09% na seca. Na época chuvosa não houve diferença significativa tanto no rendimento como no teor. A composição química dos óleos essenciais de L. gracilis apresentou altos níveis de terpenos, 92% na época chuvosa e 96% na época seca. No ensaio com irrigação os valores de teor e rendimento de todos os genótipos são menores quando comparado com o ensaio sem irrigação. De maneira geral a espécie L. gracilis, quanto à presença de água no solo, apresenta estabilidade na composição química do óleo essencial independente da época do ano, uma vez que as plantas submetidas à irrigação, mesmo no verão, produziram óleo essencial em quantidade e qualidade semelhantes à época do inverno. O óleo essencial de L. gracilis apresenta alta atividade carrapaticida, comprovados pelas concentrações letais dos genótipos LGRA-201 (1,31 mg.mL-1) e LGRA-106 (4,66 mg.mL-1), demonstrando eficiência no controle desse parasita. Os ensaios demonstraram que as concentrações 0,45; 0,91 e 2,75mg.mL-1 de todos os genótipos de L. gracilis inibiram completamente o desenvolvimento do patógeno T. paradoxa, correspondendo a uma porcentagem de inibição do crescimento micelial de 100%. A concentração de 0,18mg.mL-1 de óleo essencial foi suficiente para reduzir significativamente o número de esporos de T. paradoxa. A concentração fungicida mínima de T. paradoxa foi encontrada entre as concentrações de 0,80 a 0,98mg.mL-1 para os óleos essenciais e 0,26mg.mL-1 para o carvacrol, e 0,35mg.mL-1 para o timol.
409

Morfo-anatomia e fitoquímica de Cymbopogon densiflorus (Steud.) Stapf e Cymbopogon nardus (L.) Rendle (Poaceae: Panicoideae) / Morphology, anatomy and phytochemistry of Cymbopogon densiflorus (Steud.) Stapf and Cymbopogon nardus (L.) Rendle

BARBOSA, Lília Cristina de Souza 28 September 2007 (has links)
Made available in DSpace on 2014-07-29T15:16:37Z (GMT). No. of bitstreams: 1 Dissertacao part 1 Lilia Cristina.pdf: 320067 bytes, checksum: 69f0c85320512078b0a799d535fe13a5 (MD5) Previous issue date: 2007-09-28 / The genus Cymbopogon Sprengel belong to the Poaceae family and it has 40 species distributed in Tropical and Subtropical Africa, Asia and Australia, although some species went introduced in America. Many species of this genus are cultivated for the extraction of essential oil, from their leaves, with large medicinal, food and industrial importance. The species in focus, Cymbopogon densiflorus (Steud.) Stapf and C. nardus (L.) Rendle are originated from Africa and Asia, respectively. This research had as objective, to broaden the knowledge about the species C. densiflorus and C. nardus, by the morphological and anatomy studies from leaves and culms, phytochemical analysis and essential oil analysis from the leaves. Anatomical studies have been of relevant importance to the pharmacognosy researches, mainly for the identification of many vegetal raw materials. Several times, these raw materials are known by the same popular name or then, they are commercialized with contaminated agents or with other parts of the specie. Through of anatomical analysis, it was checked commons characters, such as leaf lamina and sheath amphistomata, stomatas with guard cells dumbbell and subsidiary cells dome-shape, rares in adaxial surface and abundant in abaxial surface, predominated in intercostal zones. The adaxial and abaxial surfaces had long cells and short cells: cork and dumb-bell and cross-shaped silica cells, these last it is placed in costal zones; macro-hairs and micro-hairs abundant in abaxial surface. In the leaf lamina, bulliforms cells are presents in adaxial surface, they were alternated with fibers in the costal zones and the mesophyll is homogeneous with chlorenchyma radiated to the bundle sheaths and arm cells with walls invaginated that they determined the intervenal distance by one or three cells, characterized Kranz anatomy. Bundle sheaths collateral, of 1st, 2nd and 3rd orders with single vascular bundle sheaths. The cap region is constituted by sclerenchyma and the epidermis has silica cells. However, both species had different anatomical features, as the form of midrib, in the leaf laminas; C. densiflorus showed colourless parenchyma cells in the mesophyll of leaf sheaths, that they do not exist in C. nardus. In the culms, numbers of metaxylem vessels in the each side of protoxylem vessels in vascular bundles: 1, in C. densiflorus, 2 and 3, in C. nardus; and the presence of sclerenchyma cylinder and fistula in C. nardus, absent characters in C. densiflorus. Moreover, in C. densiflorus, while C. nardus showed these characters. The preliminary phytochemistry analysis C. densiflorus and C. nardus leaves evidencied flavonoids, saponins, coumarins and traces of cardioactive glycosides. In the essential oil analysis, C. densiflorus leaves showed trans-p-mentha-1(7),8-dien-2-ol, trans-p-mentha-2-8-dien-1-ol, cis-carveol and cis-p-mentha-2-8-dien-1-ol as majority constituents; while C. nardus leaves had geraniol, citronellol and citronellal. The anatomical characters observed can be important to the taxonomic determinations of species studied, in the genus. Through the results found, it verifies the phytotherapics potential of both species. Future researches in isolation and purify of the secondary metabolites, pharmacologics and toxicologics analysis of extracts and of the essential oil, it will be important to assure the therapeutic efficiency of these. / O gênero Cymbopogon Sprengel pertence à família Poaceae e compreende 40 espécies, distribuídas pela África Tropical e Subtropical, Ásia e Austrália, embora algumas foram introduzidas na América. Diversas espécies deste gênero são cultivadas para a extração de óleos essenciais, a partir de suas folhas, sendo então de grande importância medicinal, alimentar e industrial. As espécies em estudo Cymbopogon densiflorus (Steud.) Stapf e C. nardus (L.) Rendle, são originárias da África e Ásia, respectivamente. Esta pesquisa teve por objetivo, ampliar o conhecimento sobre as espécies C. densiflorus e C. nardus, por meio do estudo morfo-anatômico das folhas e colmo, prospecção fitoquímica e análise dos óleos essenciais das folhas. Estudos anatômicos têm sido de relevante importância para pesquisas farmacognósticas; principalmente para a identificação de diversas matérias-prima vegetal, que muitas vezes são conhecidas pelo mesmo nome popular ou então, comercializadas com contaminantes ou de outras partes da mesma espécie. Por meio das análises anatômicas verificaram-se caracteres comuns entre ambas as espécies, tais como lâminas e bainhas foliares anfiestomáticas, estômatos com células-guarda halteriformes e células subsidiárias em forma de cúpula, raros na face adaxial e abundantes na face abaxial predominando nas regiões intercostais. As faces adaxial e abaxial apresentam células longas e células curtas: suberosas e silicificadas halteriforme e cruciforme, sendo as últimas localizadas nas regiões costais; macrotricomas e microtricomas predominam na face abaxial. Nas lâminas foliares, as células buliformes estão presentes na face adaxial da epiderme, intercaladas por fibras na região costal e o mesofilo é homogêneo disposto radialmente aos feixes vasculares, com distância intervenal de uma a três células, caracterizando anatomia Kranz. Os feixes vasculares colaterais, de 1ª, 2ª e 3ª ordens com bainha de feixe única. A região do bordo é formada por fibras e a epiderme apresenta células silicificadas. Entretanto, ocorrem características anatômicas distintas entre as duas espécies, como formato da nervura central, nas lâminas foliares; C. densiflorus apresenta células parenquimáticas incolores, na bainha foliar, que estão ausentes em C. nardus e o número de elementos de metaxilema em cada lado dos elementos de protoxilema: 1, em C. densiflorus e 2 a 3, em C. nardus e presença de cilindro esclerenquimático e medula fistulosa em C. nardus, caracteres ausentes em C. densiflorus. A análise fitoquímica preliminar das folhas de C. densiflorus e C. nardus evidenciou flavonóides, saponinas, cumarinas e traços de heterosídeos cardioativos. Na análise dos óleos essenciais, as folhas de C. densiflorus apresentaram trans-p-menta-1(7),8-dien-2-ol, trans-p-menta-2-8-dien-1-ol, cis-carveol e cis-p-menta-2-8-dien-1-ol, como constituintes majoritários; enquanto que em C. nardus foram geraniol, citronelol e citronelal. Os caracteres anatômicos observados podem ser importantes para as determinações taxonômicas das espécies estudadas. Por meio dos resultados encontrados, verifica-se o potencial fitoterápico de ambas as espécies. Futuras pesquisas em isolamento e purificação dos metabólitos secundários, análises farmacológicas e toxicológicas dos extratos e dos óleos essenciais, serão importantes para assegurar a eficácia terapêutica destas.
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Caractérisations chimiques et biologiques d’extraits de plantes aromatiques oubliées de Midi-Pyrénées / Chemical and biological characterizations of extracts of medieval aromatic plants from Midi-Pyrenees

El Kalamouni, Chaker 13 December 2010 (has links)
Les plantes aromatiques font parties des richesses naturelles du patrimoine de la région Midi-Pyrénées mais apparaissent cependant de moins en moins valorisées. Dans le cadre de la recherche de nouveaux aromatisants naturels de type WONF, nous avons choisi d'adopter la voie de valorisation des plantes aromatiques médiévales de cette région car elles ont toujours fait l'objet de cueillette à l'état sauvage sans jamais être cultivées. Dans une première étape, une étude bibliographique a été réalisée, à partir d'anciens ouvrages botaniques et de bases de données scientifiques, afin d'identifier les plantes régionales traditionnellement utilisées par nos ancêtres pour leurs activités aromatisantes, culinaires ou médicinales. Nous avons sélectionné cinq plantes aromatiques : Achillea millefolium, Calamintha grandiflora, Tanacetum balsamita, Myrrhis odorata et Monarda didyma. Dans une deuxième étape, des études physico-chimiques, sensorielles et biologiques des fractions volatiles et non volatiles, obtenues après extractions des plantes médiévales sélectionnées, ont été réalisées pour juger de leurs activités aromatiques, antioxydantes et antibactériennes ainsi que de leur intérêt dans le cadre de nouvelles réglementations européennes. Les résultats de ces travaux montrent des activités odorantes, antioxydantes et antibactériennes significatives pour l'ensemble des plantes sélectionnées. Dans une troisième étape, du fait de la rareté du végétal étudié, nous nous sommes intéressés à deux voies analytiques d'évaluation rapide de la composition de l'huile essentielle native de ces plantes aromatiques ; premièrement au moyen d'un échantillonnage classique couplé à un détecteur à forte sensibilité comme la chromatographie bidimensionnelle et deuxièmement par un échantillonnage spécifique couplé à un détecteur classique pour lequel nous avons développé un appareillage novateur dénommé "Crushing Finger Device" (CFD). Ce dernier permet de mimer instrumentalement l'écrasement de la feuille entre les doigts et de piéger les composés volatils odorants émis en vue de leur analyse chromatographique ultérieure. Enfin, pour une application pré-industrielle, afin d'élargir le champ d'application de ces plantes aromatiques, des études d'infusion des plantes et d'aromatisation des huiles végétales par les huiles essentielles ont été mises en place. Durant le processus d'aromatisation de l'huile végétale, les volatils émis par la plante ou par l'huile essentielle donnent un goût et une saveur spécifique tout en délivrant une activité biologique notable. / Midi-Pyrenees region has a rich and unvalorized wild vegetal heritage, especially for aromatic plants. In the framework of the search for new natural flavorings e.g. WONF, we chose to adopt the way of valorization of the medieval aromatic plants of this region, because they have been always picked in a wild state without being ever grown. In a first step, a global bibliographical survey study based on historical books, library archived documents and computerized data banks, was made in order to identify regional plants which were used by our ancestors for their odorous, culinary or medicinal activities. We selected five aromatic plants, e.g. Achillea millefolium, Calamintha grandiflora, Tanacetum balsamita, Myrrhis odorata and Monarda didyma. In a second step, physico-chemical, sensory and biological studies of volatiles and non volatiles fractions, obtained by extractions of the selected medieval plants were carried out, to judge their aromatic, antioxidant and antibacterial activities and their interest within the framework of new european regulations. Theses results show a significant odorous, antioxidant and antimicrobial activities for all selected plants. In a third step, such plants were rare or their harvesting problematic, inducing a limited sampling. We decided to investigate two strategic approaches to perform a rapid evaluation of native essential oil, based either on a classic sampling with a specific/ultra sensitive detection such as Comprehensive GC, nor the use of a specific/high effective sampling system with a classic detection. This last methodology was based on a self designed apparatus “Crushing Finger Device” (CFD), allowing to copy the crushing of leaves between fingers and to trap the volatiles emitted to their later chromatographic analysis. Finally, in the aim to expand the use of aromatic plants, also to enlarge the assortment of oil products, a pre-industrial application were carried out. Infusion of plants and flavoring of vegetable oil by essential oil were studied. During processing of aromatized vegetable oil, volatiles from added aromatic plants or essential oil migrate to oil to give a specific aroma and a significant biological activity. Plantes aromatiques oubliées, Huile essentielle, Antioxydant, Antibactérien, Simulateur de froissement, Composés d’arômes, Achillea millefolium, Calamintha grandiflora, Tanacetum balsamita, Myrrhis odorata, Monarda didyma.

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