Techn. Universiẗat, Diss., 2003--Clausthal. / Enth.: Bd. 1. Dissertation. Bd. 2. Techn. Dokumentation.

La biodiversité des micro-algues constitue un réel potentiel pour la recherche et l’industrie. En comparaison des plantes terrestres, elles sont une piste prometteuse pour les biocarburants. Néanmoins, un certain nombre de verrous technologiques restent à lever comme l’extraction de l’huile algale. L’objectif de cette thèse a donc consisté en l’innovation et le développement de nouvelles méthodologies dits « vertes » d’extraction de lipides de micro-algues pour une application biocarburant.La première partie de ce manuscrit propose une alternative à l’utilisation de solvants pétrochimiques (n-hexane) pour l’extraction des lipides à partir d’une biomasse sèche grâce aux solvants terpéniques d’origine végétale.Ces résultats encourageants ont permis dans une seconde partie de s’orienter vers le développement d’une technique permettant l’extraction des lipides de micro-algues humides (80% d’humidité) par des solvants terpéniques : le SDEP (Simultaneous Distillation and Extraction Process).Afin d’accélérer le processus d’extraction, dans la troisième et dernière partie de ce travail les micro-ondes ont permis d’intensifier ce procédé. Les micro-ondes permettent un échauffement rapide de l’eau environnante et contenue dans les cellules impliquant ainsi une libération rapide du contenu cellulaire vers le milieu extérieur. Ce travail a consisté en l’intensification et l’optimisation de cette technique d’extraction (SDEP) destinée à l’extraction des lipides à partir de micro-algues humides : le SDEP assisté par micro-ondes. L’appareillage permet des extractions rapides, non destructrices et généralisables à différentes espèces de micro-algues discutées dans cette troisième partie / The biodiversity of microalgae is a real potential for research and industry. Compared to terrestrial plants, they are a promising route for biofuels. Still, a number of technological locks is to lift as the the algal oil extraction. The objective of this thesis has consisted of innovation and development of new methodologies, so-called “green” extraction of lipid of microalgae for biofuel application.The first part of this manuscript proposes an alternative to the use of petrochemical solvents (n-hexane) extraction of lipids on a dry biomass with terpene solvents from plant origin.These encouraging results have allowed in a second part of move towards the development of a technique for the extraction of lipids of wet microalgae (80% of humidity) by terpene solvents; the SDEP (Simultaneous Distillation and Extraction Process).To accelerate the process of extraction, in the third and final part of this work the microwaves have allowed to intensify this process. Microwave allow a fast heating of water surrounding and contained in cells thus implying a rapid release of the cell contents into the environment. Our work consisted in the intensification and optimization of the extraction technique (SDEP) intended for the extraction of lipids from wet microalgae: SDEP assisted by microwaves. The apparatus allows rapid and non-destructive extractions that can be generalizable for different species of microalgae discussed in this third part

CoordenaÃÃo de AperfeiÃoamento de NÃvel Superior / A β-ionona (4-[2,6,6-trimetill-1-ciclohexeno]-3-buten-2-ona) à um sesquiterpeno (terpenoide degradado - C13) presente na estrutura molecular do retinol, β-caroteno e Ãcido retinÃico, sendo formado a partir da via do mevalonato em diferentes tipos de plantas. As pesquisas sobre as atividades biolÃgicas da β-ionona ainda sÃo incipientes e poucos resultados com este composto sÃo encontrados na literatura. Este estudo visa investigar a atividade da β-ionona no modelo de lesÃo gÃstrica induzida por etanol. A manipulaÃÃo dos animais e os protocolos experimentais foram registrados na ComissÃo de Ãtica em Pesquisa Animal (CEPA) sob o nÃmero 87/2011. Camundongos Swiss (n = 8), em jejum de 18 h, receberam, por gavagem, BI nas doses de 6,25; 12,5; 25; 50 e 100 mg/kg. ApÃs 60 min da administraÃÃo de BI os animais receberam 0,2 ml de etanol absoluto por gavagem. Decorridos 60 min dessa administraÃÃo, os animais foram sacrificados, os estÃmagos removidos e analisados para determinaÃÃo do Ãndice de lesÃo. A avaliaÃÃo histopatolÃgica do estÃmago foi realizada atribuindo escores aos parÃmetros de edema, hemorragia, perda de cÃlulas epiteliais e infiltrado inflamatÃrio. Para investigar o envolvimento de mediadores no efeito de BI, os animais receberam indometacina (10 mg/kg; v.o.), L-NAME (20 mg/kg; i.p.), ODQ (10 mg/kg; i.p.), glibenclamida (5 mg/kg; i.p.) e capsazepina (5 mg/kg; i.p) antes do tratamento com BI (12,5 mg/kg; v.o.). Misoprostol (50 Âg/kg v.o), L-arginina (600 mg/kg; i.p.), diazÃxido (3 mg/kg; i.p.) e capsaicina (0,3 mg/kg; v.o.) foram utilizados padrÃo positivo. Os nÃveis de nitrito e glutationa foram dosados na mucosa do estÃmago para investigar o efeito da BI sobre os nÃveis de NO e seu efeito antioxidante, respectivamente. O tratamento dos animais com a BI (12,5; 25; 50 e 100 mg/kg), reduziu significativamente e de forma dose-dependente, a Ãrea da lesÃo gÃstrica induzida pelo etanol para (11,41  2,0; 7,92  1,8*; 6,32  2,0 e 1,43  0,42 % respectivamente). Entretanto, a BI na menor dose avaliada (6,25 mg/kg), nÃo apresentou reduÃÃo significativa da Ãrea ulcerada (21,97  1,8%). A administraÃÃo de BI reduziu os escores de hemorragia, edema e a perda de cÃlulas epiteliais. A Indometacina e capsazepina nÃo foram capazes de reverter o efeito protetor da BI. O prÃ-tratamento dos animais com L-NAME, ODQ e Glibenclamida reverteu o efeito gastroprotetora da BI, mostrando o envolvimento do NO e canais KATP no seu mecanismo de aÃÃo. O grupo prÃ-tratado com BI (12,5 mg/kg v.o.) mostrou uma maior concentraÃÃo de nitrito (24,18 mM) quando comparado ao grupo controle (17,68 mM). O prà tratamento com BI foi efetivo em proteger contra o dano oxidativo (346,4  60,32 Âg/g de tecido), evitando a depleÃÃo nos nÃveis de GSH no tecido. Estes resultados indicam que a β-ionona possui efeito gastroprotetor no modelo de LesÃo GÃstrica induzida por Etanol mediado pela via NOGMPcKATP e atravÃs da mediaÃÃo do terpeno na depleÃÃo dos nÃveis de GSH provocado pelo etanol. / The β-ionone (4-[2,6,6-cyclohexene-1-trimetill]-3-butene-2-one) is a sesquiterpene (degraded terpenoid - C13) present in the molecular structure of retinol and β-carotene acid retinoic being formed from the mevalonate pathway in different types of plants. Research on the biological activities of β-ionone are still incipient and limited results with this compound are found in the literature. This study aims to investigate the activity of β-ionone in the model of ethanol-induced gastric injury. Handling of animals and experimental protocols were recorded by the Ethics Committee on Animal Research (CEPA) under number 87/2011. Swiss mice (n = 8), fasted 18 hours, were orally treated with BI at doses of 6.25, 12.5, 25, 50 and 100mg/kg. After 60 min of administration BI animals received 0.2 ml of absolute ethanol po. After 60 min this administration, the animals were sacrificed, the stomachs removed and analyzed to determine the rate of injury. Histologic examination of the stomach was performed by assigning scores to the parameters of edema, hemorrhage, loss of epithelial cells and inflammatory infiltrate. To investigate the role of mediators in BI effect, animals received indomethacin (10 mg / kg, po), L-NAME (20 mg / kg, ip) ODQ (10 mg / kg, ip), glibenclamide (5 mg / kg, ip) and capsazepine (5 mg / kg, ip) before treatment with BI (12.5 mg / kg, po). Misoprostol (50 mg / kg po), L-arginine (600 mg / kg, ip), diazoxide (3 mg / kg, ip) and capsaicin (0.3 mg / kg, po) was used positive pattern. The levels of nitrite and glutathione were measured in the stomach mucosa to investigate the effect of BI on the levels of NO and its antioxidant effect, respectively. Treatment of animals with the BI (12.5, 25, 50 and 100 mg / kg) reduced significantly and dose-dependent manner, the area of ethanol-induced gastric lesion to (11.41  2.0, 7 92 *  1.8, 6.32  2.0 and 1.43  0.42% respectively). However, the BI lowest tested dose (6.25 mg / kg) showed no significant reduction of the ulcerated area (21.97  1.8%). The administration of BI scores decreased hemorrhage, edema and loss of epithelial cells. The capsazepine and indomethacin were not able to reverse the protective effect of BI. Pretreatment of animals with L-NAME, ODQ and glibenclamide reversed the gastroprotective effect of BI, showing the involvement of NO and KATP channels in its mechanism of action. The group pretreated with BI (12.5 mg / kg po) showed a higher concentration of nitrite (24.18 mM) compared to the control group (17.68 mM). The pretreatment BI was effective in protecting against oxidative damage (346.4  60.32 mg / g of tissue), preventing depletion of GSH levels in tissue. These results indicate that the β-ionone has gastroprotective effect in the model of ethanol-induced gastric injury mediated by the NO cGMP K ATP and terpene through the mediation of the GSH depletion induced by ethanol.

Submitted by Jaqueline Silva (jtas29@gmail.com) on 2014-11-18T17:15:19Z No. of bitstreams: 2 Dissertacao Jorge Luiz Vieira dos Anjos.pdf: 1923779 bytes, checksum: 68298e97b9af0abd00eec5540da11ee7 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) / Approved for entry into archive by Jaqueline Silva (jtas29@gmail.com) on 2014-11-18T17:15:58Z (GMT) No. of bitstreams: 2 Dissertacao Jorge Luiz Vieira dos Anjos.pdf: 1923779 bytes, checksum: 68298e97b9af0abd00eec5540da11ee7 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) / Made available in DSpace on 2014-11-18T17:16:00Z (GMT). No. of bitstreams: 2 Dissertacao Jorge Luiz Vieira dos Anjos.pdf: 1923779 bytes, checksum: 68298e97b9af0abd00eec5540da11ee7 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) Previous issue date: 2008-02-18 / The interaction of the skin penetration enhancers DL-menthol, -terpineol, 1,8-cineole and (+)-limonene with membranes of the uppermost skin layer, the stratum corneum (SC) and with multilamellar vesicles from 1,2-dipalmitoyl-sn-glycero-3-phosphaticylcholine (DPPC)is investigated by electron paramagnetic resonance (EPR) spectroscopy using spin-labeled analogs of androstanol ASL),stearic acid (5-DSA), methyl stearate (5-DMS) and a small spin label 2,2,6,6-tetramethylpiperedine-1-oxyl (TEMPO). The terpenes were added to SC samples using ethanol as a co-solvent (20% ethanol in the buffer), the effect of ethanol on the SC also was investigated. The spectra of spin labels ASL, 5-DSA and 5-DMS in the membranes of SC are characterized by the presence of two spectral components differing in mobility.Component 1 was attributed to the spin labels H-bonded to the headgroups, while component 2 was assigned to the spin labels H-bonded to water molecules or temporally non-hydrogen-bonded. EPR results showed that ethanol in the range 0-70% did not alter the fluidity in SC membranes or the relative fractions of these two components. Instead, ethanol only caused a selective extraction of spin labels, indicating that ethanol acts as extractor and not as fluidizer when facilitates molecular permeation in the skin. Addition of 1% DLmenthol to the solvent containing 20% ethanol increases both the mobility and the fraction of spin labels in the component 2 (more mobile spectral component). Similarly, with the addition of 1,8-cineole, the spin probes were gradually transferred from the motionally more restricted component 1 to the more mobile component 2. The spectrum of the spin label TEMPO in the membranes of SC allows for the determination of the actual partition coefficient and rotational diffusion rates of the spin probe in the aqueous and hydrocarbon environments. The enthalpy changes,H°,to transfer the spin probe from the aqueous to the hydrocarbon phase, as well as the activation energies associated to its rotational motion, were considerably smaller for SC when compared to DPPC, indicating less pronounced thermal reorganizations for SC samples. For DPPC,all terpenes increased both the partition coefficient and the rotational diffusion rate of the spin label in the membrane, except in the liquid-crystalline phase. These results suggest that the terpenes,effectively acting as spacers in the membrane,fluidize the lipids and cause ruptures in the hydrogen-bonded network of the membrane-water interface, with consequent displacements of spin probes towards the hydrophobic core. The EPR spectra of maleimide derivative spin label (6-MSL)covalently attached to stratum corneum proteins indicate that 1,8-cineole does not alter the dynamics of protein backbones.Instead, this terpene only increases the solvent s ability to dissolve and mobilize the nitroxide side chain, which is in agreement with its low irritation response. / A interação dos aumentadores de permeação da pele DL-mentol, -terpineol, 1,8-cineole e (+)-limoneno com as membranas da camada mais externa da pele, o estrato córneo (EC) e com vesículas multilamelares de 1,2-dipalmitoyl-sn-glycero-3-phosphaticylcholine (DPPC) foi investigado por espectroscopia de ressonância paramagnética eletrônica (RPE) utilizando marcadores de spin análogos do androstanol (ASL), acido esteárico (5-DSA) e estearato de metila (5-DMS), além de um pequeno marcador anfifílico, o 2,2,6,6-tetramethylpiperedine-1-oxyl (TEMPO), que se particiona entre as fases aquosa e hidrocarbônica. Como os terpenos foram adicionados ao EC usando soluções do etanol a 20% no tampão, foram também investigados os efeitos do etanol sobre as membranas do EC. Os espectros dos marcadores de spin ASL, 5-DSA e 5-DMS nas membranas de EC são caracterizados pela presença de duas componentes espectrais diferindo em mobilidade. A componente 1 foi atribuída aos marcadores de spin que formam ligações de hidrogênio com os grupos polares da membrana, enquanto que a componente 2 foi atribuída aos marcadores de spin que formam ligações de hidrogênio com as moléculas de água ou que, temporariamente, não estão formando ligações de hidrogênio. Os resultados de RPE mostraram que o etanol em concentrações variando de 0-70% não causa alteração de fluidez nem alteração das frações relativas das duas componentes espectrais. Ao invés disso, o etanol apenas causou uma seletiva extração dos marcadores lipídicos, indicando que os efeitos do etanol como facilitador advém de sua capacidade de extrair lipídios da membrana. Com a adição de 1% de L-mentol ao solvente contendo 20% de etanol houve um aumento tanto da mobilidade quanto da fração dos marcadores de spin da componente 2 (componente espectral mais móvel). Analogamente, com a adição de 1,8-cineole, os marcadores de spin foram gradualmente transferidos da componente 1, de mobilidade mais restrita, para a componente 2 mais móvel. O espectro do marcador de spin TEMPO nas membranas de EC permite determinar o coeficiente de partição e a taxa de difusão rotacional do marcador de spin nos ambientes aquoso e hidrofóbico. As mudanças de entalpia, H°, para transferir o marcador de spin da fase aquosa para fase hidrocarbônica, bem como as energias de ativação associadas com o movimento rotacional, foram consideravelmente menores para o EC em relação às amostras de DPPC, indicando reorganizações térmicas menos pronunciadas para as membranas do EC. Para DPPC, todos os terpenos aumentaram tanto o coeficiente de partição quanto a taxa de difusão rotacional dos marcadores de spin na membrana, exceto na fase líquido-cristalina. Estes resultados sugerem que os terpenos agem efetivamente como espaçadores dos lipídios da membrana reduzindo seu empacotamento e aumentando sua fluidez, desse modo causando rupturas da rede de ligações de hidrogênio na interface membrana-água e assim gerando deslocamentos dos marcadores de spin para o core hidrofóbico. O espectro de RPE do marcador de spin derivado do maleimido (6-MSL) covalentemente ligado às proteínas do EC indicou que o 1,8-cineole não altera a dinâmica do esqueleto protéico. Ao invés disso, este terpeno apenas aumenta a habilidade do solvente em dissolver e mobilizar a cadeia lateral do nitróxido, o que está em acordo com seu baixo potencial de irritação.

Submitted by Taiwany Oliveira (taiwanyrodriguess@gmail.com) on 2018-10-22T14:08:28Z No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) minha tese pronta em pdf.pdf: 3260829 bytes, checksum: 4f79fe4884cb35fde794ffb3be8d205b (MD5) / Approved for entry into archive by Marcos Roberto Gomes (mrobertosg@gmail.com) on 2018-10-22T15:26:52Z (GMT) No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) minha tese pronta em pdf.pdf: 3260829 bytes, checksum: 4f79fe4884cb35fde794ffb3be8d205b (MD5) / Approved for entry into archive by Divisão de Documentação/BC Biblioteca Central (ddbc@ufam.edu.br) on 2018-10-23T14:13:43Z (GMT) No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) minha tese pronta em pdf.pdf: 3260829 bytes, checksum: 4f79fe4884cb35fde794ffb3be8d205b (MD5) / Made available in DSpace on 2018-10-23T14:13:43Z (GMT). No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) minha tese pronta em pdf.pdf: 3260829 bytes, checksum: 4f79fe4884cb35fde794ffb3be8d205b (MD5) Previous issue date: 2018-02-05 / CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Copaifera multijuga Hayne is a large plant species, popularly known as copaiba, native to Latin America and Africa. They are widely used in Amazonian folk medicine, due to the properties of oleoresin extracted from the trunk of their trees, mainly used as: diuretic, laxative, anti-tetanic, anti-inflammatory, antitussive, healing and anti-tumor. Therefore, it is of great importance for research aimed at identifying in plants substances with potential medical and biotechnological purposes. Therefore, this work aimed to search for the transcriptome of C. multijuga Hayne, which was sequenced using the Roche 454 platform, obtaining a total of 638,576 reads, assembled using the de novo methodology using the MIRA and TRINITY platforms. Being generated, from the assembly by TRINITY 53.319 contigs and 62.839 by assembly MIRA. The transcriptome annotation was performed using BLASTx (NCBI) and the functional annotation through the Gene Ontology (GO) bank. The results were categorized according to GO, where the contigs were grouped in the categories: "Cell Component" with 6.249 contigs involved in this category, "Molecular Function" with a total of 17.208 contigs and "Biological Process" with 9,499 contigs. In the three categories the contigs evidenced are involved in the primary plant metabolism. A total of 184 unigenes were detected in 22 clusters, mainly involved in responses to plant oxidative stress, terpenes, important metabolites involved in the formation of copaiba oleoresin, diterpenes (resinous portion of oleoresin) and sesquiterpenes (volatile components of oil) and unigenes related to vegetal pigmentation such as: flavonoids, carotenoids and anthocyanins. In phylogenetic analysis, evolutionary comparisons of terpene synthase enzymes, copaiba oil formation components, with enzymes from the NCBI database were made. C. multijuga TPS4-2 unigene had similarity to other Copaifera TPS4-2 terpene sequences available from the bank. Thus, in this work the transcriptome of C. multijuga was carried out with new assembly and annotation, which leads to the perspective of studies with the unigenes encoding enzymes components of the oleoresin evidenced in this work, aiming with this future research for biotechnological purposes. / Copaifera multijuga Hayne é uma espécie de planta de grande porte, popularmente conhecida como copaíba, nativa da América Latina e da África. São amplamente utilizadas na medicina popular amazônica, devido as propriedades do óleo-resina extraído do tronco de suas árvores, utilizado principalmente como: diurético, laxativo, antitetânico, anti-inflamatório, antitussígeno, cicatrizante e anti-tumoral. Sendo, portanto, de grande importância para pesquisas que visem identificar nas plantas substâncias com potenciais finalidades médicas e biotecnológicas. Por isto, este trabalho visou pesquisar o transcriptoma de C. multijuga Hayne, o qual foi sequênciado utilizando a plataforma 454 Roche, sendo obtido um total de 638.576 reads, montados através da metodologia de novo com auxílio das plataformas MIRA e TRINITY. Sendo gerados, a partir da montagem por TRINITY 53.319 contigs e 62.839 pela montagem MIRA. A anotação do transcriptoma foi realizada utilizando BLASTx (NCBI) e a anotação funcional através do banco Gene Ontology (GO). Os resultados obtidos foram categorizados de acordo com GO, onde os unigenes foram agrupados nas categorias: “Componente Celular” com 6.249 contigs envolvidos nesta categoria, “Função Molecular” com total 17.208 contigs e “Processo Biológico” com 9.499 contigs. Nas três categorias os contigs evidenciados estão envolvidos no metabolismo primário vegetal. Já do metabolismo secundário foram detectados 184 unigenes, sendo organizados em 22 clusters, envolvidos principalmente em respostas ao estresse oxidativo vegetal, compostos terpenos, importantes metabólitos envolvidos na formação do óleo-resina de copaíba, diterpenos (porção resinosa do óleo-resina) e sesquiterpenos (componentes voláteis do óleo) e unigenes relacionados com a pigmentação vegetal tais como: flavonóides, carotenóides e antocianinas. Na análise filogenética foram feitas comparações evolutivas de enzimas de terpenos sintases, componentes de formação do óleo de copaíba, com enzimas do banco de dados NCBI. O unigene de TPS4-2 de C. multijuga mostrou-se mais próximo a outras sequências de terpenos TPS4-2 de Copaifera disponíveis no banco. Com isto, neste trabalho realizou-se o transcriptoma de C. multijuga com a montagem de novo e anotação o que leva a perspectiva de estudos com os unigenes codificadores de enzimas componentes do óleo-resina evidenciados neste trabalho, visando com isto futuras pesquisas para fins biotecnológicos.

Le bois est un matériau renouvelable utilisé par l’Homme pour la construction, l’ameublement, la fabrication du papier, l’énergie, etc. Le bois contient des extractibles d’un grand intérêt économique appartenant à diverses familles chimiques telles que les terpènes, les flavonoïdes, les tanins, etc. Les nœuds (base de la branche englobée dans le tronc) de certaines essences sont extrêmement riches en extractibles.Ce travail a pour objectif l’analyse des variabilités interspécifiques, intraspécifiques et intra-arbre des extractibles nodaux, afin de cibler les essences, les stations et les parties de l’arbre les plus riches. Pour cela, les nœuds de vingt-trois essences, puis ceux de quinze sapins ayant poussé dans des conditions différentes ont été extraits par différents solvants et analysés. Les résultats confirment la richesse des nœuds par rapport au duramen et à l’aubier pour toutes les essences. Globalement, les nœuds des résineux contiennent plus d’extractibles que les feuillus. Les principaux composés identifiés chez les résineux sont des lignanes, des stilbènes, des flavonoïdes et des terpènes. L’acide gallique et des flavonoïdes sont présents chez les feuillus. L’étude du profil vertical montre que les concentrations diminuent de la base du houppier vers la cime de l’arbre. De plus, les résultats mettent en évidence l’influence des conditions de croissance puisque les arbres dominants, et/ou ayant poussé selon des sylvicultures dynamiques sont particulièrement riches en extractibles nodaux. Ces résultats permettent d’envisager la valorisation des coproduits des industries du bois en tant que ressource de molécules bioactives pour diverses applications. / Wood is a renewable material used by man for construction, furniture, paper making, energy, etc. Wood contains extractives of great economic value which belong to various chemical families such as terpenes, flavonoids, tannins, etc. The knots (base of the branch embedded in the trunk) of some tree species are extremely rich in extractives.This study aims at analysing the inter-specific, intra-specific and within-tree variabilities of knotwood extractives to target the richest species, stations and tree parts. For that purpose, the knots of twenty-three species and those of fifteen firs grown under different conditions were extracted using several solvents and analysed. The results confirm the richness of knots compared to heartwood and sapwood for all species. Overall softwood knots contain mainly more extractives than hardwoods. The main compounds identified in softwoods are lignans, stilbenes, flavonoids and terpenes Gallic acid and flavonoids are present in hardwoods. The study of the vertical profile shows that concentrations decrease from the base of the crown to the tree tip. In addition, the results highlight the influence of growth conditions since dominant trees and/or those grown according to dynamic silvicultures are particularly rich in knot extractives. These results allow considering the valorization of wood industries by-products as bioactive molecules resource for various applications.

Among Nature's creation, terpenoids are more versatile and exciting compounds, and provide fertile ground for developing and testing new synthetic strategies because of their phenomenal structural diversity. The thesis entitled “Enantiospecific Synthesis of Tetraquinane Diterpenes Crinipellins” describes the first enantiospecific synthesis of norcrinipellin and crinipellins, and the tricyclic core structure of tricycloillicinone, ialibinones, and takaneones. In the thesis, the compounds are sequentially numbered (bold) and references are marked sequentially as superscripts and listed at the end of the thesis. All the spectra included in the thesis were obtained by xeroxing the original NMR spectra. Crinipellins, the first group of natural products to contain a tetraquinane carbon framework, were isolated in 1985 by the research groups of Steglich and Anke from the submerged cultures of the basidiomycete Crinipellis stipitaria. Recently, In 2010, Shen and Li also reported the isolation of four new crinipellins from the Crinipellis stipitaria 113. In the present thesis, first enantiospecific synthesis of norcrinipellin and crinipellins has been described. To begin with, (S)-campholenaldehyde was transformed into the (1R,5R)-7,8,8-trimethylbicyclo[3.3.0]oct-6-en-3-one employing an intramolecular rhodium carbenoid insertion of a diazoketone, which was then transformed into the methyl (1R,2S,6R,8S,10R)-10-methoxy-2-methyl-5-oxotricyclo[6.3.0.02,6]undecane-4-carboxylate via rhodium carbenoid promoted activation of a tertiary methyl group to generate the cis, anti, cis-linear triquinane. The triquinane obtained was then transformed into ethyl 4-[(1R,2S,6S,8S,10R)-10-methoxy-2,5dimethyl-3-oxotricyclo[6.3.0.02,6]undec-4-ene-6-yl]butanoate by a sequence of reactions including an alkylative 1,3-enone transposition, which on intramolecular Michael addition reaction followed by DBU mediated equilibration generated a 5:4 mixture of ethyl (1S,3S,5R,7R,8S,11S,12R) and (1S,3S,5R,7R,8S,11S,12S)-5-methoxy8,11-dimethyl-9-oxotetracyclo[6.6.0.01,11.03,7]tetradecane-12-carboxylates, which were transformed into (12R) and (12S)-15-hydroxy-5-methoxy-20-norcrinipellin-9-ones and (12S) and (12R)-5-methoxy-20-norcrinipell-15-en-9-ones. The methodology has been further modified and extended for the first enantiospecific synthesis of (12R) and (12S) 15-hydroxy-5-(methoxymethoxy)crinipellin-9-ones In 1995, Fukuyama and coworkers reported the isolation of tricycloillicinone from Illicium tashiroi, containing an interesting 3,4,4-trimethyltricyclo[5.3.1.01,5]undecane system. This tricyclic structure was also present in two groups of acylphloroglucinoid natural products, ialibinones and takaneones. An enantiospecific synthesis of the tricyclic core structure of tricycloillicinone, ialibinones, and takaneones have been accomplished starting from (S)-campholenaldehyde employing a transannular RCM reaction as the key step, (S)-Campholenaldehyde was converted into methyl (5R)-6,6,7-trimethyl-3-oxobicyclo[3.3.0]octa-1,7-diene-2-carboxylate via the methyl (1R,5R)-6,6,7-trimethyl-3-oxobicyclo[3.3.0]oct-7-ene-2-carboxylate, which was then transformed into (1R,3S,5S)-3-allyl-7,8,8-trimethyl-5-vinylbicyclo[3.3.0]oct6-en-3-ol containing the vinyl and allyl groups at C-1 and C-3 carbons syn to each other. Transannular RCM reaction of the hydroxy diene led to the tricyclic core structure of tricycloillicinone. Further elaboration of the side chain at C-3 position led to the tricyclic core structure of ialibinones, and takaneones.

No description available.

Terpenes are secondary metabolites produced by plants and they have promising roles in plant defense and pharmaceuticals. They are synthesized by terpene synthases and these enzymes are part of a complex plant metabolic pathway. Diterpene biosynthesis requires co-expression of class II and class I diterpene synthases (diTPSs) to convert geranylgeranyl diphosphate (GGPP), the common precursor, into a C20 intermediate substrate. These substrates then use cytochrome p450s (CYPs) as their final steps to form diterpene scaffolds. CYPs are monooxygenases that change the redox status of their substrates into final diterpene products. Medicago truncatula was used as my model organism to investigate how legumes synthesize these secondary metabolites to contribute to crop defense improvement in the future. Seven diTPSs - MtTPS17, MtTPS18, MtTPS19, MtTPS37, MtTPS38, MtTPS39, and MtTPS40 - in M. truncatula have been identified. MtTPS38 was found to produce ent-CPP and MtTPS37 used ent-CPP to yield ent-kaurene. Combinatorial expression showed that MtTPS38 and MtTPS37 react together to produce ent-kaurene, a precursor for an important plant hormone gibberellin (GA). CYPs have also been discovered to be clustered around MtTPS19, suggesting the possibility of MtTPS19 utilizing these CYPs for downstream reactions.

Eastern hemlock hosts the hemlock woolly adelgid, an introduced sap-feeding insect that causes rapid deterioration of the host. Like most conifers, eastern hemlock produces a variety of constitutive and induced defenses, primarily terpenoids. To explore the relationship of terpenoid defenses with adelgid infestations, we artificially infested hemlocks at a forest site and a plantation site, and compared their terpenoid concentrations to those in control trees. Infested trees showed lower terpenoid concentrations than control trees, suggesting that eastern hemlock not only fails to induce production of terpenoids in response to adelgid infestation, but becomes less able to produce carbon-based defenses due to loss of carbon resources to the adelgid. Greater light intensity may account for consistently higher terpenoid concentrations at the plantation site, supporting the explanation that carbon limitation restricts terpenoid production. Recent studies have identified a small number of individual eastern hemlock trees that demonstrate relative resistance to the hemlock woolly adelgid. We compared concentrations of terpenoids in susceptible and relatively resistant trees, both in the forest and in propagated cuttings in a common-garden setting. Terpenoid concentrations were higher in twig tissue of resistant versus susceptible trees, across six sampling dates and at both sites. Because the common-garden cuttings were free of herbivores, the higher terpenoid concentrations are interpreted as a constitutive defense. Increased levels of monoterpenes and sesquiterpenes imply an overall increase in the input of carbon precursors to both terpenoid synthesis pathways. This result suggests either an altered growth-defense balance favoring allocation of carbon resources towards production of defenses, or overall greater carbon availability in growing twig tissue of adelgid-resistant eastern hemlock individuals. We contribute detailed terpenoid data to the study of the eastern hemlock – hemlock woolly adelgid system. Our solvent extraction method permits us to examine needle and twig tissues separately, capture minor components at low concentrations, and focus on stored rather than volatilized terpenoids. By relating terpenoid concentrations to insect densities, we explore the relationships of tentatively defensive chemistry to insect population dynamics. The question remains which terpenoids, if any, directly affect hemlock woolly adelgid and what role phenols may play in the system.