Tesi: "Terpenes" – Grafiati

1

Borenberg, Fredrik. "Biofiltrering av luft förorenad med terpener : Biofiltration of air polluted with terpenes". Thesis, Växjö University, School of Technology and Design, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:vxu:diva-2000.

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Utsläpp av lättflyktiga organiska föreningar (VOC) är ett växande mijlöproblem. Biofiltrering är ett relativt billigt sätt att rena luft förorenad med VOC. Biofiltrering har också en fördel i att föroreningen helt bryts ned och inte endast övergår i en annan form. Rapporten beskriver arbetet kring två biofilter av kolonntyp. Mikroberna som användes kom från främst träflis och jord. Som förorening användes limonen och α-pinen. Analys skedde med gaskromatografi.

Vidare undersöktes om närvaro av silikonolja i filterbädden påverkade resultatet Reningskapaciteten uppgick i filtret utan olja till ca 10 - 12 g/m3.h under de första 25 dagarna i drift och ökade därefter till ca 15 - 20 g/m3.h. Motsvarande data för det oljeberikade filtret är ca 15 - 20 g/m3.h i båda fallen

Emissions of volatile organic compounds are a growing environmental problem. Biofiltration is a relatively cost efficient method to purify air polluted with VOC:s. Biofiltraion also has the benefit of completely degrading the pollutants rather than just transferring them into another phase/form. This report describes the work on two biofilters of column type. The microbes used were extracted from wood chips and soil. As pollutants limonene and α–pinene were used.

Furthermore, it was investigated how the presence of silicone oil in the filter bed affected the filtering results. The filtering capacity in the non oil enriched filter was during the first 25days 10-12 g/m3h and thereafter some 15-20 g/m3h. The efficiency of the oil enriched filter was stable at 15-20 g/m3h.

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2

Ajayi, Emmanuel Olusegun. "Interaction of terpenes and oxygenated terpenes with some drugs". Thesis, University of Fort Hare, 2012. http://hdl.handle.net/10353/418.

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SFME and HD for the extraction of essential oil in Lavandula officinalis in Alice have been reported. A total of 59 compounds were identified with the major compound being 1,8-cineole, an oxygenated monoterpene, with 46.89% and 44.84% yield obtained for HD and SFME respectively. Charge transfer (CT) complexes formed between α-pinene, 1,8-cineole and camphor as electron donors with iodine as the electron acceptor have been studied spectrophotometrically in methylene chloride solution. The Benesi- Hildebrand equation has been applied to estimate the formation constant (Kf) and molecular extinction coefficient (εCT). The value of Kf is the highest in camphor-I2 complex compared to the other two complexes. Antibacterial assessment was carried out on the various reagents, determining the MIC of individual reagents and in combination. The results show an improvement, on combination of the various reagents than when tested alone.

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3

Naik, R. H. "Synthetic studies in terpenes". Thesis(Ph.D.), CSIR-National Chemical Laboratory, Pune, 1985. http://dspace.ncl.res.in:8080/xmlui/handle/20.500.12252/3225.

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4

Peña, Carrodeguas Leticia. "Synthesis of Biobased Polymers derived from Terpenes". Doctoral thesis, Universitat Rovira i Virgili, 2017. http://hdl.handle.net/10803/454747.

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Complexos aminotrifenolats d'Al (III) i Fe (III) combinats amb un nucleòfil han estat investigats com a catalitzadors binaris en la reacció de ROCOP per a l'obtenció de polímers bio-renovables perfectament alternats. S'ha estudiat l'acoblament d'òxid de limonè i diòxid de carboni per a l'obtenció de policarbonats alternats. Aquest sistema catalític va ser capaç de produir polímers trans estereoregulares a partir del cis-òxid de limonè . El catalitzador d'Al (III) mostra potencial per transformar tots dos isòmers de l'òxid de limonè, amb nivells de conversió alts, sense necessitat d'usar dissolvent. A més, hem sintetitzat sis anhídrids tricíclics, parcial o totalment renovables, i els hem copolimeritzat amb òxid de propilè i òxid de ciclohexà. Canviant tots dos, epòxids i anhídrids, hem aconseguit variar la temperatura de transició vítria d'aquests polímers en 120 °C, des de 66 °C fins a l'excepcional temperatura de 184 °C. Hem investigat l'ús d’epòxids derivats de terpens (òxid de limonè, òxid de carè, diòxid de limonè i òxid de mentè) per ROCOP en presència de diversos anhídrids aromàtics. Aquestes reaccions de copolimerització van ser efectuades usant aminotrifenolats basats en Fe (III) i PPNCl permetent-nos obtenir poliésters semi-aromàtics parcialment renovables amb temperatures de transició vítria de 59 a 243 ºC. Finalment, s'han usat aminotrifenolats d'Al (III) i PPNCl per a la preparació d'una sèrie de biocarbonats derivats d'àcids grassos. Aquest sistema catalític permet convertir els epòxids derivats d'àcids grassos en ciclocarbonats mantenint un alt nivell de diastereoselectivitat.
Complejos aminotrifenolatos de Al (III) y Fe (III) combinados con un nucleófilo han sido investigados como catalizadores binarios en la reacción de ROCOP para la obtención de polímeros bio-renovables perfectamente alternados. Se ha estudiado el acoplamiento de óxido de limonene y dióxido de carbono para la obtención de policarbonatos alternados. Este sistema catalítico fue capaz de producir polímeros trans estereoregulares a partir de óxido de limoneno cis. El catalizador de Al (III) muestra potencial para transformar ambos isómeros del óxido de limonene, con niveles de conversión altos, sin necesidad de usar disolvente. Además, hemos sintetizado seis anhídridos tricíclicos parcial o totalmente renovables y los hemos copolimerizado con óxido de propileno y óxido de ciclohexano. Cambiando ambos, epóxidos y anhídridos, hemos logrado variar la temperatura de transición vítrea de estos polímeros en 120 °C, desde 66 °C hasta la excepcional temperatura de 184 °C. Hemos investigado el uso de epóxidos derivados de terpenos (óxido de limoneno, óxido de careno, dióxido de limonene y oxido de menteno) para ROCOP en presencia de varios anhídridos aromáticos. Estas reacciones de copolimerización fueron llevadas a cabo usando aminotrifenolatos basados en Fe (III) y PPNCl permitiéndonos obtener poliesters semi-aromáticos parcialmente renovables con temperaturas de transición vítrea de 59 a 243 ºC. Finalmente, se han usado aminotrifenolatos de Al (III) y PPNCl para la preparación de una serie de biocarbonatos derivados de ácidos grasos. Este sistema catalítico permite convertir los époxidos derivados de ácidos grasos en ciclocarbonatos manteniendo un alto nivel de diastereoselectividad.
Aminotriphenolate Al (III) and and Fe (III) complexes combined with a nucleophile have been investigated as binary catalytic systems for ROCOP reactions to afford perfectly alternating bio-renewables polymers. The coupling of limonene oxide and carbon dioxide to obtain polycarbonates has been studied. These catalysts are able to produce stereoregular trans configured polymers from cis limonene oxide. The Al (III) catalyst shows the potential to transform both stereoisomers of limonene oxide with high conversion levels under neat conditions. Furthermore, we synthesized six partially or fully renewable tricyclic anhydrides and copolymerized them with propylene oxide and cyclohexene oxide. By varying both the epoxide and the anhydride, we were able to increase the Tg of the resulting polymers over nearly 120 °C from 66 °C to an exceptionally high 184 °C. We have investigated the use of terpene derived epoxides (limonene oxide, carene oxide, limonene dioxide and menthene oxide) for the ROCOP in the presence of various aromatic anhydrides. These copolymerization reactions were performed using Fe(III) based aminotriphenolate complex and PPNCl providing partially bio-based semi-aromatic polyesters with glass transition temperatures spanning from 59 to 243 ºC. Finally, Al (III) aminotriphenolate and PPNCl were used for the preparation of a series of fatty acid derived biocarbonates. This catalyst system allows to convert the fatty acid derived epoxides maintaining high levels of diastereospecificity.

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5

Carboni, Thaís Ribeiro [UNESP]. "Análise de crescimento, trocas gasosas, potencila antioxidante e óleo essencial de Origanum vulgare L. ssp. vulgare". Universidade Estadual Paulista (UNESP), 2013. http://hdl.handle.net/11449/108463.

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Plantas de Origanum vulgare L. ssp. vulgare foram cultivadas em casa de vegetação, tipo Paddy-Fan, em solução nutritiva no2 de Hoagland e Arnon (1950) 100% (completa), 75%, 50% e 25%. O objetivo do estudo foi avaliar o crescimento, trocas gasosas e potencial antioxidante de plantas da subespécie Origanum vulgare L. ssp. vulgare submetidas a variação da concentração de nutrientes em solução nutritiva, bem como avaliar a influência desse fator na caracterização química do óleo essencial sintetizado por elas. Aos 20, 40, 60, 80 e 100 dias após o transplante das mudas para a solução nutritiva, a massa seca de folhas (MSF), massa seca total (MST) e as suas áreas foliares (AF) foram determinadas para a avaliação dos índices fisiológicos de razão de área foliar (RAF), razão de massa foliar (RMF), taxa assimilatória líquida (TAL) e taxa de crescimento relativo (TCR). As avaliações de trocas gasosas foram realizadas aos 20, 45 e 85 dias após o transplante. Aos 20, 40, 60, 80 e 100 dias após o transplante, amostras frescas da parte aérea das plantas foram coletadas, congeladas em nitrogênio líquido e armazenadas em freezer, para posterior realização das análises de pigmentos, flavonóides totais, fenóis totais, ácido ascórbico e potencial antioxidante (DPPH). O óleo essencial foi avaliado aos 60, 80 e 100 dias após o transplante. O experimento foi inteiramente casualizado, com 4 repetições, em esquema 4x5 (4 tratamentos e 5 épocas de colheita) para avaliação do crescimento e análises bioquímicas, 4x3 para as trocas gasosas e 3X3 para a análise da composição do óleo essencial. Os resultados obtidos sugerem que a variação da concentração da solução nutritiva pode estimular ou inibir o desenvolvimento de Origanum vulgare L. ssp. vulgare. As plantas cultivadas com soluções mais concentradas apresentaram diminuição de AF, MSF e MST, que interferiu com os índices fisiológicos. Além disso, ...
Origanum vulgare L. ssp. vulgare plants were grown in a Paddy-Fan greenhouse, with 100% (complete), 75%, 50%, and 25% Hoagland and Arnon (1950) #2 nutrient solution. The objective of the study was to evaluate the influence of the complete nutrient solution with the various diluted solutions, with regards to the growth of the Origanum vulgare L. ssp. vulgare, its gas exchange, antioxidant potential, and chemical composition during its growth. At 20, 40, 60, 80 and 100 days after transplanting the seedlings to the nutrient solution the following observations were measured: dry matter of leaves (DML) and total (DMT), and leaf area of the leaves (AL). These measurements were used to evaluate the physiological index, leaf area ratio (LAR), leaf weight ratio (LWR), net assimilation rate (NAR), and relative growth rate (RGR). The exchange of gases was evaluated at 20, 45 and 85 days after transplantation. At 20, 40, 60, 80 and 100 days after transplantation, fresh samples of foliage were collected and frozen in liquid nitrogen. These samples were stored in a freezer for later analyzes of pigmentation, total flavonoids, total phenols, ascorbic acid, and antioxidant potential. The essential oil was evaluated at 60, 80 and 100 days after transplantation. The experiment was randomized with the following factors: four repetitions in a design 4x5 (4 treatments and 5 harvest timeframe) to evaluate the growth and biochemical results, 4x3 for exchange of gases and 3X3 for the analysis of essential oil composition. The results of this experiment indicates that the variation of the nutrient solution’s concentration can stimulate or inhibit the growth Origanum vulgare L. ssp. vulgare, particularly in more concentrated solutions. Plants grown with more concentrated solutions showed a decrease of DML, DMT and AL, which interfered with the physiological indices. Additionally, a reduction in the exchange of gases was present, as well as an increase in the ...

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6

Souza, e. Silva Juliana Martins de. "Estereo e sitio seletividade da epoxidação de diferentes terpenos com AI2O3 obtida via sol-gel". [s.n.], 2005. http://repositorio.unicamp.br/jspui/handle/REPOSIP/249519.

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Orientador: Ulf Friedrich Schuchardt
Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Quimica
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Mestrado
Quimica Inorganica
Mestre em Química

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7

Carboni, Thaís Ribeiro. "Análise de crescimento, trocas gasosas, potencila antioxidante e óleo essencial de Origanum vulgare L. ssp. vulgare /". Botucatu, 2013. http://hdl.handle.net/11449/108463.

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Orientador: Carmen Silvia Fernades Boaro
Banca: Márcia Ortiz Mayo Marques
Banca: Jão Domingos Rodrigues
Resumo: Plantas de Origanum vulgare L. ssp. vulgare foram cultivadas em casa de vegetação, tipo Paddy-Fan, em solução nutritiva no2 de Hoagland e Arnon (1950) 100% (completa), 75%, 50% e 25%. O objetivo do estudo foi avaliar o crescimento, trocas gasosas e potencial antioxidante de plantas da subespécie Origanum vulgare L. ssp. vulgare submetidas a variação da concentração de nutrientes em solução nutritiva, bem como avaliar a influência desse fator na caracterização química do óleo essencial sintetizado por elas. Aos 20, 40, 60, 80 e 100 dias após o transplante das mudas para a solução nutritiva, a massa seca de folhas (MSF), massa seca total (MST) e as suas áreas foliares (AF) foram determinadas para a avaliação dos índices fisiológicos de razão de área foliar (RAF), razão de massa foliar (RMF), taxa assimilatória líquida (TAL) e taxa de crescimento relativo (TCR). As avaliações de trocas gasosas foram realizadas aos 20, 45 e 85 dias após o transplante. Aos 20, 40, 60, 80 e 100 dias após o transplante, amostras frescas da parte aérea das plantas foram coletadas, congeladas em nitrogênio líquido e armazenadas em freezer, para posterior realização das análises de pigmentos, flavonóides totais, fenóis totais, ácido ascórbico e potencial antioxidante (DPPH). O óleo essencial foi avaliado aos 60, 80 e 100 dias após o transplante. O experimento foi inteiramente casualizado, com 4 repetições, em esquema 4x5 (4 tratamentos e 5 épocas de colheita) para avaliação do crescimento e análises bioquímicas, 4x3 para as trocas gasosas e 3X3 para a análise da composição do óleo essencial. Os resultados obtidos sugerem que a variação da concentração da solução nutritiva pode estimular ou inibir o desenvolvimento de Origanum vulgare L. ssp. vulgare. As plantas cultivadas com soluções mais concentradas apresentaram diminuição de AF, MSF e MST, que interferiu com os índices fisiológicos. Além disso, ...
Abstract: Origanum vulgare L. ssp. vulgare plants were grown in a Paddy-Fan greenhouse, with 100% (complete), 75%, 50%, and 25% Hoagland and Arnon (1950) #2 nutrient solution. The objective of the study was to evaluate the influence of the complete nutrient solution with the various diluted solutions, with regards to the growth of the Origanum vulgare L. ssp. vulgare, its gas exchange, antioxidant potential, and chemical composition during its growth. At 20, 40, 60, 80 and 100 days after transplanting the seedlings to the nutrient solution the following observations were measured: dry matter of leaves (DML) and total (DMT), and leaf area of the leaves (AL). These measurements were used to evaluate the physiological index, leaf area ratio (LAR), leaf weight ratio (LWR), net assimilation rate (NAR), and relative growth rate (RGR). The exchange of gases was evaluated at 20, 45 and 85 days after transplantation. At 20, 40, 60, 80 and 100 days after transplantation, fresh samples of foliage were collected and frozen in liquid nitrogen. These samples were stored in a freezer for later analyzes of pigmentation, total flavonoids, total phenols, ascorbic acid, and antioxidant potential. The essential oil was evaluated at 60, 80 and 100 days after transplantation. The experiment was randomized with the following factors: four repetitions in a design 4x5 (4 treatments and 5 harvest timeframe) to evaluate the growth and biochemical results, 4x3 for exchange of gases and 3X3 for the analysis of essential oil composition. The results of this experiment indicates that the variation of the nutrient solution's concentration can stimulate or inhibit the growth Origanum vulgare L. ssp. vulgare, particularly in more concentrated solutions. Plants grown with more concentrated solutions showed a decrease of DML, DMT and AL, which interfered with the physiological indices. Additionally, a reduction in the exchange of gases was present, as well as an increase in the ...
Mestre

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8

Di, Matteo Marco. "Selective C-H Activation of Terpenes". Electronic Thesis or Diss., Sorbonne université, 2024. https://accesdistant.sorbonne-universite.fr/login?url=https://theses-intra.sorbonne-universite.fr/2024SORUS001.pdf.

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Ce travail de thèse porte sur la découverte de nouvelles stratégies pour l'activation/fonctionnalisation C-H des terpènes, avec un accent particulier sur le (+)-limonène et la catalyse au palladium. Tout d'abord, nous avons décrit le couplage C(sp2)-H/C(sp2)-H déshydrogénant catalysé par le Pd(II) entre le limonène et des alcènes pauvres en électrons, avec une extension à divers terpènes et terpénoïdes. Ensuite, nous avons étudié la post-fonctionnalisation d'un produit issu du couplage déshydrogénant développé et de l'éthynylbenzène en conditions micellaires. Par la suite, nous avons développé avec succès le couplage redox neutre C(sp2)-H/C(sp2)-X entre le (+)-limonène et des bromoalcènes. Cette stratégie, qui est complémentaire par rapport au couplage déshydrogénant, nécessite une charge plus faible du catalyseur au palladium et du sel d'argent par rapport au couplage étudié précédemment. Enfin, nous avons étudié de nouvelles approches pour la synthèse du cannabidiol (CBD). Des travaux futurs seront nécessaires pour évaluer les stratégies et atteindre la cible synthétique
This thesis work is dealing with the discovery of new strategies for the C-H activation/functionalization of terpenes, with particular emphasis on (+)-limonene and palladium catalysis. Firstly, we described the dehydrogenative Pd(II)-catalyzed C(sp2)-H/C(sp2)-H coupling between limonene and electron-poor alkenes, with extension to various terpenes and terpenoids. Therefore, we studied the post-functionalization of one product stemming from the dehydrogenative coupling and ethynylbenzene under micellar regime. Secondly, we successfully developed the Pd(II)-catalyzed redox neutral C(sp2)-H/C(sp2)-X coupling between (+)-limonene and bromoalkenes. This strategy, which is complementary with respect to the dehydrogenative coupling, needs a lower loading of the palladium catalyst and of the silver salt with respect to the previously studied coupling. Finally, we investigated the study of new approaches to cannabidiol (CBD). Of course, future work will be necessary to evaluate the strategies and reach the target

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9

Abell, Andrew David. "Some mechanistic, stereochemical and structural problems in terpenoid chemistry /". Title page, contents and summary only, 1985. http://web4.library.adelaide.edu.au/theses/09PH/09pha141.pdf.

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10

Flach, Adriana. "Ecologia quimica de Maxillariinae, Spathodea campanulata e Meliponiinae". [s.n.], 2005. http://repositorio.unicamp.br/jspui/handle/REPOSIP/249340.

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Orientador: Anita Jocelyne Marsaioli
Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Quimica
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Resumo: O presente trabalho foi dividido em três partes todas relacionadas a química das relações entre os seres vivos. Na primeira parte do trabalho estudou-se a química da polinização de orquídeas da subtribo Maxillariinae em termos da composição dos voláteis e recompensas florais coletadas pelos polinizadores. Discutiu-se também os compostos envolvidos na atração dos polinizadores de Mormolyca ringens e Trigonidium obtusum. Identificou-se, nesta etapa uma série de compostos: hidrocarbonetos, terpenos, álcoois, aldeídos, cetonas, ésteres, etc. Em um segundo momento determinou-se a composição química do néctar de Spathodea campanulata (Bignoniaceae), uma planta relatada como tóxica. Identificou-se, além de carboidratos, compostos secundários como terpenos, esteróides e carboidratos acetilados. Também foram identificados os constituintes voláteis: 1-octen-3-ol e 1-octen-3-ona. Na última parte do trabalho explorou-se a modificação química das ceras de duas espécies de abelhas que estabeleceram uma relação de convivência em um mesmo ninho. A composição química das ceras de operárias de colônias puras e de colônias mistas de M. scutellaris apresentaram perfis químicos diferentes produzindo nas colônias puras uma série de n-alcanos e n-alcenos enquanto que a colônia mista apresentou elevado percentual de acetato de triacontanila. As ceras das colônias de M. rufiventris apresentaram variações nas proporções de hidrocarbonetos.
Abstract: This work is presented in three distincts parts, ali of them concerning the chemistry involved in inter-specific relations. In the first part we discuss the pollination chemistry of orchids, subtribe Maxillariinae, in terms of floral volatiles and rewards collected by polinators. It is also discussed the compounds involved in polinattors attraction by Mormlyca rigens and Trigonidium obtusum. At this stage we have identified hydrocarbons, terpenes, alcohols, aldehydes, ketones, esters, etc. In the second chapter we analyzed the chemical composition of Spathodea campanulata (Bignoniaceae) nectar. Occurence wich has been considered toxic, due to the dead insects inside the flower. Morever, we identified some secondary metabolites as terpenes, steroids and acetylated sugars. Volatiles compounds as 1-octen-3-ol and 1-octen-3-one were also identified. The last part explores the chemical modification in waxes from two bees species that established coexistence in the same nest. We compare the chemical modification of waxes from worker bees in pure and mixed colonies of Meliponia rufiventris and Melipona scutellaris. Revealing that the ratio of alkanes, alkenes, were altered in M. rufiventris colonies. M. scutellaris pure colonie produce alkanes and alkanes and the chemistry of mixed colonies were altered producing high ratio of triacontanyl acetate.
Doutorado
Quimica Organica
Doutor em Ciências

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Dionísio, Ana Paula. "Produção e estudo biológico de compostos de aromas obtidos a partir da biotransformação de carotenóides". [s.n.], 2010. http://repositorio.unicamp.br/jspui/handle/REPOSIP/256730.

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Orientador: Gláucia Maria Pastore
Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos
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Resumo: A biotransformação de carotenóides é um campo de crescente interesse para a indústria de aromas, uma vez que podem ser obtidos compostos considerados como ¿naturais¿, de grande aplicabilidade industrial e que podem apresentar, em muitos casos, propriedades biológicas interessantes. Desta forma, o objetivo do presente trabalho foi efetuar um estudo de biotransformação de carotenóides seguida de uma otimização do processo, avaliar o uso de sub-produtos industriais para barateamento do processo, realizar a biotransformação de outros substratos terpênicos para formação de compostos voláteis e por fim, estudar as propriedades biológicas dos produtos voláteis derivados de carotenóides. O capítulo 1 apresenta uma revisão bilbiográfica sobre bio-oxidação de terpenos, focando especialmente no uso monoterpenos e b-caroteno como substrato. O capítulo 2 trata do isolamento de micro-organismos a partir de fontes naturais ricas em b-caroteno. Das mais de 400 linhagens avaliadas, cerca de 60 apresentaram um potencial para biotransformação de carotenóides, evidenciado por um halo de degradação característico formado ao redor da colônia inoculada em uma placa contendo b-caroteno. Em seguida, a técnica de microextração em fase sólida (SPME) foi usada para extração e concentração dos compostos voláteis formados na biotransformação pelas linhagens selecionadas, e os compostos foram identificados por CG-DIC e CG-EM. O estudo das variáveis envolvidas no processo de biotransformação de b-caroteno pela linhagem LB398APD é reportada no Capítulo 3. Para isso, um Placket-Burman (PB16) foi realizado inicialmente para seleção de variáveis, e seguindo o processo de planejamento experimental, um fatorial 22 com os parâmetros significativos do PB foi realizado. Em posse dos resultados da otimização, o Capítulo 4 retrata o uso de meios alternativos para o desenvolvimento de biomassa pela linhagem LB398APD. O micro-organismo possuiu um desenvolvimento em meio manipueira superior ao meio convencional, com condições ótimas do sistema alcançadas usando 60 % de manipueira, 30 °C e 300 rpm (produção de biomassa em 24h = 4,6g.L-1). Entretanto, quando glicerol foi usado como fonte de carbono, o desenvolvimento de biomassa não foi obtido com sucesso. Além dos ensaios usando b-caroteno como substrato, outros terpenos também foram avaliados com algumas linhagens fúngicas isoladas, e essa biotransformação é reportada no Capítulo 5. Carvona e carveol foram obtidos quando o limoneno foi usado como única fonte de carbono, e o uso de Paecilomyces sp. parece ser a primeira vez onde esse micro-organismo é reportado na literatura para ensaios e biotransformação. Por fim, o Capítulo 6 trata de alguns estudos ¿in vitro¿ com compostos de aromas derivados de carotenóides. Os resultados alcançados geram a possibilidade para esses compostos seres utilizados industrialmente como ¿aromas funcionais¿, pois apresentaram resultados extremamente interessantes quando esses terpenos foram usados em 12 células tumorais, representando resultados muitas vezes superiores ao controle positivo (doxorrubicina)
Abstract: The biotransformation of carotenoids is a field of growing interest to the flavor industry, once the compounds obtained can be labeled as "natural", with high industrial applicability and that may present, in many cases, interesting biological properties. Chapter 1 reviews a variety of techniques developed till the present days for the oxidation of terpenes, especially monoterpenes and ß-carotene, to volatile compounds. In sequence, Chapter 2 deals with the screening of microorganisms from natural sources rich in ß-carotene. Among more than 400 strains evaluated, 60 exhibited a potential for biotransformation of carotenoids, as evidenced by a characteristic degradation halo formed around the colonies inoculated on a plate containing ß-carotene. Afterwards, the solid phase microextraction technique (SPME) was used to extrain and concontrate the aroma compounds produced by the selected strains, and the analysis were conduced by GC-FID and GC-MS. The study of the variables involved in the biotransformation of ß- carotene by the LB398APD strain is reported in Chapter 3. For this, a Placket-Burman (PB16) was initially performed for the screening of the variables, and following the experimental design process, a 22 factor with the significant parameters selected in the PB was performed. In sequence, Chapter 4 shows the use of alternative culture media for the biomass development by the LB398APD strain. The microorganism demonstrated a development in the cassava wastewater media higher than in the conventional media, and the optimum system conditions were achieved by using 60 % of cassava wastewater, 30 °C and 300 rpm (biomass production in 24 hours = 4.6 gL-1). In addition to the tests using ß-carotene as substrate, other terpenes were also tested with some fungal strains, and this biotransformation is reported in Chapter 5. Carvone and carveol were obtained when limonene was used as the sole carbon source. The use of Paecilomyces sp. seems to be the first report in literature for biotransformation assays. Finally, Chapter 6 deals with some in vitro studies with carotenoids derived aroma compounds. The promising results create the possibility for such compounds to be used as "functional flavors"
Doutorado
Doutor em Ciência de Alimentos

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Achotegui, Castells Ander. "The role of terpenes in the defensive responses of conifers against herbivores and pathogens". Doctoral thesis, Universitat Autònoma de Barcelona, 2015. http://hdl.handle.net/10803/323095.

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La condició sèssil de les plantes ha fet que desenvolupin un ampli ventall de defenses físiques i químiques per fer front a herbívors i patògens. Moltes plantes tenen reserves permanents de productes químics (defenses constitutives) per fer front a les agressions biòtiques immediatament, però aquestes defenses també poden augmentar o canviar proporcionalment davant d’un atac (defenses induïdes). Per altra part, podem distingir entre defenses directes, que frenen les agressions intoxicant o reduint el creixement d’herbívors i patògens, i defenses indirectes, que atreuen antagonistes dels atacants, normalment a partir d’emissions de volàtils. Dels més de 100.000 compostos químics que juguen papers defensius en les plantes, uns 20.000 són terpens, un tipus d’hidrocarburs amb un ampli ventall d’estructures i funcions. Les coníferes tenen els terpens com una de les seves principals defenses. Aquesta tesi té per objectiu descriure i aprofundir en el rol defensiu dels terpens en dues interaccions mediterrànies: pi roig (Pinus sylvestris) - processionària del pi (Thaumetopoaea pityocampa), i xiprer (Cupressus sempervirens) – xancre del xiprer (Seiridium cardinale). S’hi analitzen els terpens de teixits de plantes i fongs amb cromatografia de gasos – espectrometria de masses (GC-MS) i s’hi estudia l’expressió gènica de les sintases terpèniques amb qPCR. També s’han realitzat tests de laboratori per determinar l’impacte dels terpens sobre el creixement i la supervivència de la processionària i del xancre del xiprer. En el primer capítol es mostra que les concentracions foliars de terpens disminueixen i les emissions s’incrementen quan el pi roig és atacat per la processionària. Per saber si aquesta disminució de concentracions és deguda a la pèrdua per emissions o a una baixa biosíntesi de terpens, en el segon capítol s’estudia l’expressió gènica de dues sintases terpèniques, i es mostra que la defoliació causada per la processionària tendeix a disminuir l’expressió gènica d’aquestes sintases, fet que és poc habitual. En concordança, s’observa que les concentracions de terpens en fulles també disminueixen, suggerint una dèbil resposta defensiva del pi roig davant l’atac. En el capítol 3 s’estudien els canvis terpènics i nutricionals en fulles noves que han crescut després d’un episodi de defoliació, en dues subespècies diferents de pi roig. Una subespècie reacciona augmentant concentracions de terpens, canviant emissions i reduïnt nutrients, mentre que l’altra no mostra canvis significatius en cap paràmetre. Sorprenentment, aquestes reaccions tan diferents no semblen tenir efectes sobre la supervivència de la processionària, suggerint que aquest herbívor està adaptat a les respostes defensives dels pins. En el 4t capítol es monitoren les reaccions terpèniques en el floema i les fulles de xiprers infectats per Seiridium cardinale. Els resultats mostren fortes induccions de terpens en el floema, incloent la formació de terpens de novo i canvis en les proporcions d’aquests compostos. També es poden constatar canvis en les emissions foliars de terpens. En el 5è i últim capítol es comparen les respostes en el floema d’arbres resistents i no resistents al xancre del xiprer, i s’observa que la inducció terpènica és més forta en els arbres resistents. També es presenten els tests realitzats per veure la capacitat d’inhibició fúngica dels terpens del xiprer. En els resultats es pot apreciar que els terpens induïts per l’atac són molt inhibidors i que aquesta inhibició és més dependent de la concentració que en els terpens constitutius. Així mateix, es demostra que el fong és capaç de biotransformar i detoxificar tres terpens del xiprer, suggerint mecanismes d’adaptació a les defenses de l’arbre. Aquesta tesi aporta nova i valuosa informació sobre el rol dels terpens en dues interaccions mediterrànies, alhora que aprofundeix en alguns aspectes encara poc estudiats del rol defensiu dels terpens en les coníferes.
Plants, due to their sessile condition, have developed a plethora of physical and chemical defences to make front to herbivores and pathogens. Chemical defences are very versatile: permanent reserves of chemical compounds (constitutive defences) are useful to face aggressions immediately, but these defences can also increase or change when biotic aggressions are detected (induced defences). We can also distinguish between direct defences, which fight the aggressions by intoxicating or slowing the growth of the insects and pathogens, and indirect defences, which attract antagonists of the agents attacking the plant, usually by volatile cues. Terpenes, a type of hydrocarbons that has a very wide range of structures and functions, are known to be very important chemical defences of conifers. This thesis aimed to describe and deepen in the role that terpenes play in two Mediterranean interactions: Scots pine (Pinus sylvestris) – pine processionary moth (Thaumetopoea pityocampa, PPM) and Italian cypress (Cupressus sempervirens) – cypress canker (Seiridium cardinale). We analyzed the terpenes from plant and fungal tissues with Gas Cromatography – Mass Spectrometry (GC-MS) and quantified the gene expression of terpene synthases with qPCR. We also conducted laboratory bioassays that determined the impact that these defences have on survival and growth of insects and pathogens. In the first chapter we observed that two Scots pine subspecies coexisting in natural stands decrease their needle terpene concentrations and increase their foliar emissions when PPM feeds on them. To know wether the lower concentrations were due to a decrease in terpene biosynthesis or to high terpene emission losses, in chapter 2 we made use of qPCR, and we observed that PPM feeding tended to reduce the gene expression of terpene synthases of local and systemic needles. This was unexpected, as synthases are usually up-regulated in front of herbivory. Accordingly, needle terpene concentrations also decreased, suggesting a weak terpene response of Scots pine needles to PPM infestations. In chapter 3, conducted in the same study site as chapter 1, we studied the terpene and nutritional responses of new Scots pine needles to previous defoliation by the PPM. One Scots pine subspecies grew new needles with increased terpene concentrations, changes in terpene emissions and decreased concentrations of nutrients. Contrarily, the other subspecies did not show any clear response, indicating contrasting reactions to herbivory between the subspecies. Surprisingly, these contrasting reactions did not produce any difference in the survival of young PPM larvae, suggesting that PPM, a specialist herbivore, may be adapted to the defensive responses of pines. In the 4th chapter we monitored the reactions in the phloem and the leaves of cypresses infected by Seiridium cardinale. Results showed strong increases of terpene concentrations in infected phloem and foliar terpene emission increases after infection. Results suggested thus that terpenes play an important role in the defence of the Italian cypress. The 5th and final chapter compared the terpene phloem responses of resistant and non-resistant cypresses, observing a more intense response in resistant trees. We also tested the growth inhibition caused by Italian cypress defences, and found that many of the induced terpenes were very inhibitory and had more concentration-dependent inhibitions than the major, constitutive terpenes. We finally investigated the biotransformation capacities of S. cardinale, and observed that this fungus can biotransform and detoxify three cypress, indicating adaptation to tree defences. This thesis provides thus new and valuable information about two important Mediterranean interactions, but also deepens in some understudied features of terpene conifer defence, such as variety resistance, systemic defences or terpene biotransformation capacities of conifer pathogens.

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Norström, Emelie. "Terpenes as renewable monomers for biobased materials". Thesis, KTH, Skolan för kemivetenskap (CHE), 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-49875.

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With the ambition to decrease the utilization of fossil fuels, a development of those raw materials that today only are seen as waste products is necessary. One of those waste products is turpentine. Turpentine is the largest natural source of terpenes in the world today. The main components are the terpenes α-pinene, β-pinene and 3-carene. In this project, different polymerisation techniques have been evaluated to polymerise limonene with the aim to make a material out of the green raw material, turpentine. Limonene is a terpene that can be found in turpentine. It has a planar structure and should work as a model for other terpenes. Previous work on polymerising terpenes has focused on succeeding with performing polymerisations of terpenes utilizing the techniques of cationic polymerisation and radical polymerisation. However, this has been done without the aim to make a material out of the polymers. In this project, on the other hand, the main focus has been to obtain a polymer that can be used as a basis for a material. Techniques that have been applied are: radical polymerisation, cationic polymerisation and thiol-ene polymerisation. In this study, attempts to homopolymerise limonene and also copolymerise it with other synthetic monomers, such as styrene, have been performed with both radical polymerisation and cationic polymerisation. The procedure for the radical polymerisation has been conducted following the work by Sharma and Srivastava. [1] Even though several articles have been published about radical copolymerisations of limonene with other synthetic monomers, the radical polymerisations have not succeeded in this project. Further, the technique of thiol-ene chemistry has shown that limonene can be used in polymerisations; limonene reacts spontaneously with 2-mercaptoethyl ether forming a viscous polymer. The obtained polymers have been characterized with proton nuclear magnetic resonance(1H-NMR), size exclusion chromatography (SEC), matrix-assisted laser desorption ionization-time of flight mass spectroscopy (MALDI-TOF MS), differential scanning calorimetry (DSC), fourier transform infrared spectroscopy (FTIR) and Raman spectroscopy.

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Boontawan, Apichat. "A membrane bioreactor for biotransformation of terpenes". Thesis, Imperial College London, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.413713.

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Zhang, Xinming. "Biomimetic assembly of reactive units for the total synthesis of marine natural products from dual biosynthetic origin". Thesis, Université Paris-Saclay (ComUE), 2019. http://www.theses.fr/2019SACLS318.

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Le manuscrit de thèse traite de la synthèse totale de molécules naturelles de structures particulièrement intrigantes. Deux familles de molécules naturelles issues du monde marin ont été ciblées dans ce travail : les halichonadines et les araiosamines.- La famille des halichonadines nous plongent dans le domaine des terpènes d’origine marine. Isolées d’éponges du genre Halichondria, deux structures ont particulièrement retenues notre attention : les halichonadines K et L. En effet, non seulement, ces deux molécules complexes contiennent une partie terpénique de type eudesmane (halichonadine C, un isonitrile naturel) mais aussi un cœur central de nature peptidique constitué, notamment, d’une pipéridine disubstituées par des fonctions acide carboxylique. Une partie est dédiée à comprendre comment dans la nature, des molécules de type isonitrile sont produites et peuvent réagir dans des voies de biosynthèse. Par ailleurs, le travail expérimental s’est organisé de la façon suivante :1- Concevoir une synthèse efficace de l’halichonadine C. Une stratégie au départ de la santonine est développée. La présence d’un groupement isopropyle sur la structure finale s’est avérée poser un nombre important de problèmes. Cependant, un composé très avancé a été obtenu figurant tout le squelette et l’atome d’azote nécessaire à la finalisation de la synthèse de l’halichonadine C.2- Concevoir une synthèse du cœur central permettant de contrôler la stéréochimie relative des deux fonctions carboxyliques en alpha de l’atome d’azote. Plusieurs stratégies ont été étudiées faisant appel notamment à une double addition de Michael ou à des réactions inspirées de la synthèse de la tropinone. Le cœur central est ainsi accessible en un nombre très limité d’étapes.Les résultats sont très encourageants et la quasi-totalité des pièces du puzzle sont là pour entrevoir rapidement la synthèse totale des halichonadines K et L.- La partie consacrée aux araisoamines (A-D, extraites d’éponges du genre Clathria) est exploratoire et permet de proposer des pistes synthétiques prometteuses pour l’accès bio-inspiré à ces molécules naturelles constituants un défi pour le chimiste. Un des défis relevés dans le travail est de concevoir des analogues synthétiques d’intermédiaires biosynthétiques très réactifs tels que des indoles aldéhydiques très instables. Une méthode pour générer in situ de telles entités a été étudiée. Les premières expériences ont été appliquées à la synthèse des « pyridiniums de Discodermia » et apparaissent prometteurs.Les travaux menés s’inscrivent dans « l’art de la synthèse totale » mais sont aussi toujours en lien avec le souci de mieux comprendre « chimiquement » comment des architectures moléculaires complexes s’assemblent au cours des voies de biosynthèse des substances naturelles
The work described in this PhD dissertation is dedicated to the total synthesis of intriguing natural product structures. Two distinct families of natural substances of marine origin have been targeted in this work: the halichonadins and the araiosamines.- With the halichonadins, we plunge into the marine terpene chemistry. Isolated from sponges of the genus Halichondria, two structures have particularly drawn our attention: halichonadins K and L. Indeed, besides two subunits of terpene origin (namely halichonadin C, a natural isonitrile) with an eudesmane skeleton, a central core of peptidic origin is also original (especially a carboxylic acid disubstituted piperidine ring). A part of the work is dedicated to understanding how, in nature, isonitrile natural products may be formed and may react. The experimental part is organized according to the two following topics:1- Devise an efficient and straightforward total synthesis of halichonadin C. A strategy starting from santonin has been studied and developed. The presence of an isopropyl pending group has attracted many synthetic problems. Anyhow, an advanced intermediate comprising the whole skeleton and the crucial nitrogen atom of the target has been reached and provides good hopes for the access to halichonadin C.2- Conceiving a strategy of the stereocontroled access to the central piperidine ring of halichonadins K and L. Several strategies have been evaluated including the recourse to double Michael additions and reactions inspired by Robinson’s tropinone synthesis. The peptidic central core is now accessible in a limited number of steps.Most of the pieces of the puzzle are in our hands at the end of this PhD to secure a rapid access to the complex targets that constitutes halichonadins K and L.- The chapter dedicated to araiosamines (A-D, isolated from sponges of the genus Clathria) is exploratory and allows to propose promising strategies for a bio-inspired synthesis that constitutes true challenges for the organic chemists. One of the challenges to take up is to prepare highly reactive indole aldehyde units that could be foreseen as chemical equivalents of postulated biosynthetic intermediates. A method to generate in situ such units is studied. The first applications have been directed to the synthesis of “Discodermia pyridiniums” and appear to be promising towards the total synthesis of these molecules.The work conducted during this PhD take place in the framework of the “art of total synthesis”. But, in our strategies, the chemical understanding of biosynthetic pathways is never far away

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Wallis, John Craig. "3-hydroxycineole, possum metabolites of 1,8-cineole /". [St. Lucia, Qld.], 2005. http://www.library.uq.edu.au/pdfserve.php?image=thesisabs/absthe19352.pdf.

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Molina, Gustavo 1983. "Biotechnological production of aroma compounds by the biotransformation of terpenes = Produção biotecnológica de compostos de aroma por biotransformação de terpenos". [s.n.], 2014. http://repositorio.unicamp.br/jspui/handle/REPOSIP/254207.

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Orientador: Gláucia Maria Pastore
Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos
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Resumo: Este trabalho de doutorado teve como principal objetivo estudar a produção biotecnológica de compostos de aroma a partir da biotransformação de terpenos, analisando potenciais biocatalisadores, processos bioquímicos diferenciados e a otimização das condições de processo envolvidas na produção destes aromas naturais para possíveis aplicações industriais. Inicialmente, o trabalho prático foi direcionado para uma série de estudos com o fungo Fusarium oxysporum 152B, visando complementar os recentes avanços alcançados pelo grupo de pesquisa na caracterização e otimização da bioconversão de R-(+)-limoneno em ?-terpineol. Desta forma, os resultados foram promissores, demonstrando o grande potencial e versatilidade deste fungo para a área, sendo que este biocatalisador foi capaz de produzir diferentes metabólitos a partir dos substratos S-(?)-limoneno, ?-pineno, ?-terpineno e linalol. Na sequência, o trabalho visou avaliar a bioconversão de S-(?)-limoneno para limoneno-1,2-diol em maiores detalhes. A produção de limoneno-1,2-diol, em condições não otimizadas, chegou a 1,2 g.L-1, sendo que foi detectada a continuação desta via metabólica quando este produto foi posteriormente metabolizado a 1-hidroxi-2- oxolimoneno, sugerindo que o fungo Fusarium oxysporum 152B possui uma via de degradação de limoneno recentemente descoberta. O trabalho prático visou também a otimização da produção de limoneno-1,2-diol por meio de uma estratégia sequencial de experimentos. Com base nas análises estatísticas, a produção deste composto a partir da bioconversão de S-(?)-limoneno pelo fungo Fusarium oxysporum 152B chegou a 3,7 g.L-1, utilizando pH 6,5, 5 g.L-1 de substrato, a 28 oC e 250 rpm de agitação. Além disso, esta foi a primeira descrição da utilização do resíduo agroindustrial conhecido como manipueira, originada ao longo do processamento da mandioca, para a produção de biomassa deste fungo, bem como uma das maiores concentrações de limoneno-1,2-diol reportadas na literatura específica. Além disso, o trabalho conduzido visou realizar uma série de comparações práticas entre a biotransformação de R-(+)-limoneno a ?-terpineol e a bioconversão de S-(?)-limoneno a limoneno-1,2-diol, pela mesma linhagem. Adicionalmente, este foi o primeiro trabalho que analisou as diferenças ultraestruturais causadas no biocatalisador ao longo do processo de bioconversão destes substratos, por meio de microscopia eletrônica de varredura e transmissão. Finalmente, foi estudada a otimização da produção de ?-terpineol, a partir da biotransformação de limoneno, utilizando o biocatalisador reconhecido como Sphingobium sp. Após o trabalho prático e análise estatística dos dados, observou-se que as melhores condições para desenvolvimento deste processo foram pH 7,0, concentração de limoneno de 350 g.L-1, agitação de 200 rpm e 28 oC. Nestas condições, a produção deste álcool monoterpênico chegou a 500 g.L-1, que pode ser considerada como a maior concentração de ?-terpineol já relatada na bibliografia de processos biotecnológicos.
Abstract: This work aimed to study the biotechnological production of aroma compounds from the biotransformation of terpenes, analyzing potential biocatalysts, biochemical processes and optimization of process conditions involved in the production of natural flavors for industrial applications. Initially, the practical work was directed to a series of studies with the fungal strain Fusarium oxysporum 152B, aiming to enhance the knowledge obtained in recent advances achieved by our research group in the characterization and optimization of the biotransformation of R-(+)-limonene into ?-terpineol. Thus, the results were promising, showing the great potential and versatility of this fungus to the specific area, and this biocatalyst was able to produce new metabolites from substrates S-(?)-limonene, ?-pinene, ?-terpinene and linalool. In the sequence, this study aimed at assessing the bioconversion of S-(?)-limonene into limonene-1,2-diol in greater detail. Thus, chapters 3, 4 and 5 were designed to a better characterization of this pathway. The production of this compound under non-optimized conditions, reached 1.2 gL-1, and the continuation of this pathway has been detected when this product was subsequently metabolized to 1-hydroxy-2-oxolimonene, suggesting that the fungus Fusarium oxysporum 152B might have a limonene degradation pathway only recently discovered. The practical work also conducted an extensive optimization of the production of limonene-1,2-diol by means of a sequential strategy. Based on statistical analyzes, the production of this compound from the bioconversion of S-(?)-limonene by the fungus Fusarium oxysporum 152B reached 3.7 gL-1, using pH 6.5, 5 gL-1 of substrate at 28 ° C and 250 rpm agitation. Moreover, this is the first description of the use of agroindustrial residue known as cassava wastewater, for the production of this fungal biomass, as well as one of the highest concentration of biotechnological limonene-1,2-diol reported in the specific literature. In addition, the research conducted aimed to perform a series of comparisons between practical conditions involved in the biotransformation of R-(+)-limonene into ?-terpineol, and the bioconversion of S-(?)-limonene into limonene-1,2-diol, for the same strain. Additionally, this is the first study that reported the ultrastructural differences along the bioconversion process of these substrates by means of scanning and transmission electron microscopy. Finally, this work evaluated the optimization of the production of ?-terpineol from the biotransformation of limonene using the biocatalyst recognized as Sphingobium sp. After the practical work and statistical analysis, it was observed that the best conditions for developing this process were pH 7.0, concentration of limonene 350 g L-1, agitation at 200 rpm and 28 oC. Accordingly, the production of the monoterpe alcohol reached 500 g.L-1, which can be considered as the highest concentration of ?-terpineol already reported in the literature for biotechnological processes.
Doutorado
Ciência de Alimentos
Doutor em Ciência de Alimentos

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Schie, Christianus Cornelis Nicolaas van. "Biosynthesis of volatile and hormonal terpenes in tomato". [S.l. : Amsterdam : s.n.] ; Universiteit van Amsterdam [Host], 2007. http://dare.uva.nl/document/40774.

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Tuzcuoğlu, Esra. "Thermal and photodehydrogenation reactions of terpenes over zeolites/". [s.l.]: [s.n.], 2003. http://library.iyte.edu.tr/tezler/master/kimya/T000253.pdf.

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Costa, Mayra Fonseca. "Co-cultivo dos fungos endofíticos Botryosphaeria parva e Saccharicola sp. : avaliação da produção metabólica /". Araraquara, 2017. http://hdl.handle.net/11449/150102.

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Orientadora: Angela Regina Araujo
Banca: Lourdes Campaner dos Santos
Banca: Elaise Gonçalves Pierri
Resumo: Historicamente, a maioria dos novos medicamentos tem sido gerada a partir de produtos naturais, os quais são definidos como metabólitos secundários de microrganismos, plantas ou animais. Atualmente o elemento-chave para a investigação de produtos naturais é o acesso a novas fontes biológicas. Nos últimos anos, um grande número de substâncias biologicamente ativas estão sendo encontrados em diversos microrganismos, as quais são produzidas pela ativação de vias biossintéticas onde vários métodos têm sido estudados para a ativação destas. Um dos métodos utilizados com este objetivo é a cultura mista de microrganismos. Metabólitos secundários de fungos têm atraído um interesse considerável, uma vez que muitos deles apresentam estruturas únicas e atividades biológicas relevantes. Uma importante classe de fungos que vem se destacando na produção de novos compostos bioativos são os fungos endofíticos. Diante disso, visando contribuir com o desenvolvimento de novos produtos naturais bioativos e entender como ocorrem as interações entre os microrganismos, além de avaliar seus potenciais biológicos, é que nesse trabalho apresentamos a realização da co-cultura de dois endófitos: Botryosphaeria parva e Saccharicola sp isolados da espécie vegetal Eugenia jambolana. Estes endófitos foram cultivados em escala reduzida (isoladamente) e escala ampliada (co-cultivo) em Czapek (300 mL) para obtenção dos extratos brutos AcOEt. Os extratos brutos AcOEt obtidos foram submetidos a análises químicas... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: Historically, most new drugs have been generated from natural products, which are defined as secondary metabolites or byproducts of microorganisms, plants or animals. Currently, the key element for the investigation of natural products is the access to new biological sources. In recent years, a large number of biologically active substances are being reported in several microorganisms, which are produced by the activation of biosynthetic pathways where several methods have been studied for their activation. One of the methods used for this purpose is the mixed culture of microorganisms. Secondary fungal metabolites have attracted considerable interest, since many of them have unique structures and relevant biological activities. An important class of fungi that has been prominent in the production of new bioactive compounds are endophytic fungi. Therefore, in this study we present the co-culture of two endophytes: Botryosphaeria parva and Saccharicola sp. isolated from the plant species Eugenia jambolana. Our objective is to contribute to the development of new bioactive natural products and to understand how the chemical interactions of these microorganisms occur, as well as to evaluate their biological potential. These endophytes were cultivated on a reduced scale (isolated) and extended scale (co-culture) in Czapek (300 mL) to obtain the crude extracts AcOEt. The crude AcOEt extracts obtained were submitted to chemical analysis (comparative thin layer chromatography, high ... (Complete abstract click electronic access below)
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21

Molina, Gustavo 1983. "Prospecção de processos biotecnológicos de interesse industrial". [s.n.], 2010. http://repositorio.unicamp.br/jspui/handle/REPOSIP/256729.

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Orientador: Gláucia Maria Pastore
Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos
Made available in DSpace on 2018-08-16T15:25:18Z (GMT). No. of bitstreams: 1 Molina_Gustavo_M.pdf: 3663264 bytes, checksum: 94506067795fea82250b3e7365a128c0 (MD5) Previous issue date: 2010
Resumo: O objetivo do presente trabalho foi efetuar estudos de biotransformação de monoterpenos para a obtenção de compostos de aromas naturais, ou bioaromas, enfatizando os processos bioquímicos envolvidos nos procedimentos empregados para possíveis aplicações industriais. Assim, o estudo se iniciou com 70 linhagens, isoladas em uma planta de processamento de suco de laranja e selecionadas em um estudo prévio pois mostraramse capazes de utilizar este R-(+)-limoneno como única fonte de carbono. Estes microorganismos foram testados quanto a sua capacidade de biotransformar este monoterpeno em compostos de aroma. Dentre todas as linhagens potencialmente degradantes do R- (+)-limoneno, apenas a linhagem LB285JLB mostrou acúmulo significativo de metabólito de interesse em concentração que justifique estudos de otimização. A seguir, o método de Superfície de Resposta foi empregado para otimizar os principais parâmetros do processo de produção de biomassa desta linhagem, utilizando glicerol como fonte de carbono. Dentre os parâmetros analisados, três (concentração de substrato, temperatura e agitação) influenciaram significativamente (p < 0,10) a produção de biomassa da linhagem LB285JLB, dentro das faixas estudadas. A otimização dessas variáveis por um Delineamento Composto Central Rotacional revelou que as condições ótimas para a fermentação foram 6-9 g.L-1 de glicerol, temperatura entre 35-40 °C e agitação de 230 a 300 rpm. Finalmente, estudos preliminares de prospecção do potencial dos microorganismos endofíticos isolados do Baru (Dipteryx alata Vog.), visando o desenvolvimento de processos biotecnológicos de interesse industrial. Até o presente momento os trabalhos conduzidos demonstraram que as linhagens endofíticas podem ter aplicação potencial em processos de produção de bioaromas a partir da biotransformação de monoterpenos, juntamente com a co-produção de enzimas. Esses resultados abrem precedentes para que novas pesquisas sejam consideradas a fim de determinar o potencial deste nicho de micro-organismos
Abstract: The objective of the present work was to study the biotransformation of monoterpenes to obtain natural flavor compounds (bioflavors), focusing the biochemical processes involved in the procedures investigated for possible industrial applications. Therefore, the study started with 70 strains, isolated in a previous study from a citrus processing plant and capable of use R-(+)-limonene as sole carbon and energy source. These microorganisms were tested for their ability to biotransform this monoterpene on flavor compounds. Among the strains potentially degrading of R-(+)-limonene, just the strain LB285JLB showed significant accumulation of interest metabolite concentration which could justify optimization studies. Subsequently, the Response Surface Methodology was employed to optimize the main parameters of the process of LB285JLB biomass production, using glycerol as carbon source. Only three (glycerol concentration, temperature and agitation) of all parameters tested influenced significantly (p < 0.1) the biomass production. TheT optimization of these variables applying a Central Composite Design revealed that the optimal biotrasformation conditions were 6-9g.L-1, 35-40 °C and 230-300 rpm. Finally, preliminary propection studies evaluating the potential of endophytes isolated from Baru (Dipteryx alata Vog.), for the development of biotechnological processes of industrial interest. To date, the studies conducted have shown that endophytic microorganisms may have potential application in biotransformation process for bioflavors production, and also should be considered with process of enzymes co-production. These results encourages that further researchs should be considered to determine the potential of these microorganisms
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Mestre em Ciência de Alimentos

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22

Abrahão, Meissa Rocha Essenfelder 1984. "Desenvolvimento de processo biotecnológico para produção de compostos de aroma por fungos endofíticos : Biotechnological process development for the production of aroma compounds through endophytic fungi". [s.n.], 2014. http://repositorio.unicamp.br/jspui/handle/REPOSIP/254210.

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Orientador: Gláucia Maria Pastore
Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos
Made available in DSpace on 2018-08-24T20:06:37Z (GMT). No. of bitstreams: 1 Abrahao_MeissaRochaEssenfelder_M.pdf: 2164946 bytes, checksum: 5d4f141c4a784953c0b6ee598b74b6e3 (MD5) Previous issue date: 2014
Resumo: A biotecnologia é uma área interdisciplinar que tem possibilitado inúmeros avanços no desenvolvimento de processos sustentáveis e na obtenção de novos produtos de interesse industrial. Entre estes exemplos estão os aromas naturais que, atualmente, são preferidos por muitos consumidores e já dominam o mercado em certas regiões como a Europa. Uma das opções biotecnológicas para a obtenção destes compostos ocorre pela biotransformação de terpenos, que são derivados de isoprenos, e substratos amplamente distribuídos na natureza. Estes compostos são classe relevante dentre os compostos de aroma e alguns podem ser obtidos a custos relativamente baixos. Limoneno e ?-pineno, por exemplo, estão disponíveis como subprodutos de indústrias de frutas cítricas e de papel, respectivamente. Estes monoterpenos são considerados substratos ideais para obtenção de derivados oxigenados, os terpenóides, muitos dos quais de grande interesse comercial. Nessa perspectiva, 51 fungos endofíticos das frutas caju (Anacardium occidentale L.), jenipapo (Genipa americana L.), sapoti (Manilkara zapota L.) e camu-camu (Myrciaria dubia), foram isolados durante este trabalho. As linhagens foram também avaliadas quanto ao potencial para biotransformação de limoneno ou ?-pineno como fontes únicas de carbono. A partir deste segundo substrato, destacaram-se dois fungos produtores de verbenona, um dos compostos chave do aroma de alecrim (Rosmarinus officinalis). A produção de verbenona por via biotecnológica mostrou um grande potencial para a continuidade dos estudos, tendo em vista que a concentração obtida foi de, aproximadamente, 200 mg/L após 288 horas de contato com o subtrato ?-pineno. Além disso, outro fungo apresentou produção de álcool perílico a partir da biotransformação de limoneno. Este produto é um terpenóide, cujos mecanismos de proteção contra o câncer já tem sido investigados e reconhecidos, aumentando o interesse na sua pesquisa e produção biotecnológica. No encerramento do trabalho, os três fungos com resultados positivos pra biotransformação de terpenos foram analisados em microscopia óptica para observação de suas morfologias e auxílio na identificação
Abstract: As an interdisciplinary field, biotechnology has allowed several advances for the development of sustainable processes and many achievements concerning production of new compounds with industrial interest. Natural aroma compounds have been frequently prioritized by costumers and dominate a considerable market share in some regions such as Europe, and one of biotechnological routes for obtaining these compounds occurs through the biotransformation of terpenes. These substrates are naturally available compounds derived from isoprene units, and represent a relevant class of aroma compounds, which can be often obtained at relatively low costs. Limonene and ?-pinene, for instance, are available as by-products in citrus and pine industries, respectively. These monoterpenes represent ideal precursors for biotechnological production, leading to their oxygenated derivatives denominated terpenoids, some of which commercially valuable. In this perspective, fifty one endophytic fungi from Brazilian fruits, such as cashew (Anacardium occidentale L.), genipap (Genipa americana L.), sapodilla (Manilkara zapota L.) and camu-camu (Myrciaria dubia) were screened during this work. Furthermore, these fungal strains were tested in the biotransformation of limonene or ?-pinene as sole carbon source. Amongst all fungi, two strains showed noteworthy capability to biotransform ?-pinene into verbenone, key compound of rosemary (Rosmarinus officinalis) aroma. The biotechnological production of verbenone proved to be an interesting strategy with a great future potential, considering that that the concentration of this product reached approximately 200 mg/L after 288 hours of contact with the substrate ?-pinene. Moreover, from the biotransformation of limonene, one fungi produced perillyl alcohol. This important terpenoid presents protection mechanisms against cancer already investigated and recognized. The practical steps achieved in this project also involved the observation of these strains with positive results through optical microscopy, in order to verify their morphology and general characteristics
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Ciência de Alimentos
Mestra em Ciência de Alimentos

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23

Almeida, Juliana Machado. "Análise do óleo essencial de variedades de lúpulo (Humulus lupulus L.) cultivadas no Brasil por cromatografia gasosa uni e bidimensional /". Botucatu, 2020. http://hdl.handle.net/11449/192720.

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Orientador: Marcia Ortiz Mayo Marques
Resumo: Pertencente à família Cannabaceae, o lúpulo (Humulus lupulus L.) é considerado um dos ingredientes mais importante da cerveja por proporcionar amargor e odor na bebida, devido aos α-ácidos e β-ácidos e ao óleo essencial presentes nas inflorescências femininas. Os óleos essenciais são responsáveis pelo perfil aromático das variedades de lúpulo, podendo variar de 0,5 a 3% de teor nos cones secos. No Brasil, o cultivo de lúpulo ainda é recente e advém de iniciativas de agricultores, em boa parte, de pequena escala, com potencial de crescimento desse nicho de mercado. Para o fomento da mesma, é importante analisar o perfil químico dos óleos essenciais, uma vez que, fatores genéticos, ambientais, de cultivo, época de colheita e processamento do material vegetal podem afetar sua composição química. O objetivo desse estudo foi caracterizar a composição química dos óleos essenciais de variedades de Humulus lupulus, cultivadas em diferentes localidades no Brasil. No total foram avaliadas 18 amostras de 13 variedades (Cascade, Chinook, TP, Medusa, Suíço, Mantiqueira, Saaz, EKG1, Columbus, Comet, Hallertau Mittelfrüch, Brazylinsk e Nugget) provenientes dos estados de São Paulo, Rio Grande do Sul e Rio de Janeiro, safra de 2019. Os óleos essenciais foram extraídos por hidrodestilação em aparato Clevenger por três horas, a partir de 45 g de cones secos. A análise da composição química dos óleos essenciais foi realizada por cromatografia em fase gasosa acoplada a espectrometria de massas (... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: Belonging to the Cannabaceae family, hop (Humulus lupulus L.) is considered one of the most important ingredients in beer by providing the bitterness and odor of the drink due to α and β-acids and to the essential oil present in its female inflorescences. Essential oils are responsible for the aromatic profile of hop varieties, ranging from 0.5 to 3% of the content in dry cones. In Brazil, the cultivation of hops is still recent and comes from initiatives of small farmers with potential expansion of this market niche. However, to promote it, it is important to analyze the essential oils chemical profile, since genetic, environment and cultivation factors, as well as harvest season and plant material processing might affect its chemical composition. Thus, the aim of this study was to characterize the chemical composition of essential oils of Humulus lupulus varieties, cultivated in different locations of Brazil. In total, 18 samples of 13 varieties (Cascade, Chinook, TP, Medusa, Suíço, Mantiqueira, Saaz, EKG1, Columbus, Comet, Hallertau Mittelfrüch, Brazylinsk and Nugget) from São Paulo, Rio Grande do Sul and Rio de Janeiro states were evaluated, from a 2019 harvest. The essential oils were extracted by hydrodistillation in Clevenger apparatus for three hours, from 45 g of dry cones. The analysis of the chemical composition of essential oils was performed by gas chromatography coupled to mass spectrometry (GC-MS) and Comprehensive two dimensional gas chromatography coupled to ... (Complete abstract click electronic access below)
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24

Fowler, D. J. "Biosynthetic studies on the non mevalonate pathway to terpenes". Thesis, Durham University, 2001. http://etheses.dur.ac.uk/3991/.

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Isoprenoids are a class of secondary metabolites that are widely distributed in Nature. This thesis describes the synthesis and feeding of isotopically labelled enriched substrates to elucidate features of a new mevalonate independent pathway to isoprenoids. Chapter 2 describes studies with a whole plant system, Mentha citrata, which produces the monoterpene linalyl acetate, and a bacterium Escherichia coli which produces ubiquinone-8. Feeding experiments with stable isotopically enriched compounds demonstrate that the terpene unit of linalyl acetate is biosynthesised via the mevalonate independent pathway, hicorporation of deuterium from [6,6-(^2)H(_2)]-glucose, [(^2)H(_3)]-alanine and [(^13)C(^2)H(_3)]-alanine into luialyl acetate show that the conversion to isopentenyl pyrophosphate does not proceed via a series of dehydrations. Feeding experiments with putative intermediates bearing deuterium into E. coli show that none of the intermediates are incorporated. This suggests that E. coli lacks a kinase to activate exogenously administered substrates fed as the free alcohols. Chapter 3 outlines biosynthesis studies on a meroterpene rosnecatone produced by the fungus R. necatrix. Intact incorporation of (^13)C from the feeding of [l,2-(^13)C(_2)]-acetate shows that the terpenoid moiety is produced via the mevalonic acid pathway and the non-terpenoid unit is polyketide derived. Incorporation of deuterium from [6,6-(^2)H(_2)]-glucose fully describes the pentaketide that delivers the non-terpenoid fragment. The effect on the metabolite production of changing the growth conditions of R. necatrix is investigated. Changing from a static culture to a submerged cultures causes an increased rate of growth, an upregulation of the production of cytochalasan E and a cessation of rosnecatone production. Screening of rosnecatone against two Human cancer cell lines shows IC(_50) values of 4.48µM and 5.78µM.

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25

Strauss, Lindie Helene. "The enzymatic release of glycosidically-bound terpenes in must". Master's thesis, University of Cape Town, 1989. http://hdl.handle.net/11427/22185.

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Bibliography: pages 79-86.
Flavour in wines is perhaps the most important factor affecting wine quality, with monoterpenoids being among the compounds contributing to flavour. In grapes there exists glycosidically-bound forms of these monoterpenes, representing a latent source of aroma. This project is a study on the ability of different enzymes to release these monoterpenes in Muscat d'Alexandrie and Weisser Riesling grapes. Different commercial enzyme preparations were characterised with respect to their catalytic properties and fractionated by ion exchange chromatography in the most active fractions. Amongst those commercial preparations tested, Rohapect C was found to be the most effective at conditions prevalent during wine making. These purified fractions were added to the above mentioned grapes to determine their effect on the release of different monoterpenes. Even though the enzymes were active on synthetic substrates, limited release of terpenes from must could be detected. Possible causes for this apparent inability to release monoterpenes were investigated. Product inhibition due to the presence of high concentrations of glucose in the must appeared to be the main cause of limited enzyme activity. In an attempt to overcome this problem, glucose in the above mentioned cultivars was oxidised to gluconic acid by glucose oxidase, prior to attempting monoterpene release by Rohapect C. Although no marked increase in the release of total terpenes occured, a significant increase in the concentrations of some individual terpenes could be observed. The effect of this on wine quality remains to be ascertained.

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26

Toke, S. M. "Synthetic studies in agrochemicals and chemical transformation of terpenes". Thesis(Ph.D.), CSIR-National Chemical Laboratory, Pune, 1989. http://dspace.ncl.res.in:8080/xmlui/handle/20.500.12252/3320.

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27

Rocha, Nayrton FlÃvio Moura. "Estudo dos efeitos farmacolÃgicos do (-)-α-bisabolol em modelos animais de nocicepÃÃo, inflamaÃÃo e Ãlcera gÃtrica em camundongos". Universidade Federal do CearÃ, 2009. http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=3969.

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Conselho Nacional de Desenvolvimento CientÃfico e TecnolÃgico
CoordenaÃÃo de AperfeiÃoamento de Pessoal de NÃvel Superior
FundaÃÃo Cearense de Apoio ao Desenvolvimento Cientifico e TecnolÃgico
O (-)-a-bisabolol, um Ãlcool sesquiterpenico comumente obtido de Matricaria chamomilla e de espÃcies do gÃnero Vanillosmopsis, foi testado em modelos animais padronizado de nocicepÃÃo, inflamaÃÃo e Ãlcera gÃstrica em camundongos. Nestes ensaios, o (-)-a-bisabolol foi utilizado nas doses de 25 e 50 mg/Kg nos modelos de nocicepÃÃo e 100 e 200 mg/Kg nos modelos de inflamaÃÃo e Ãlceras gÃstricas, administrados por via oral. O (-)-a-bisabolol demonstrou possuir atividade antinociceptiva nos modelos de nocicepÃÃo visceral induzida por Ãcido acÃtico intraperitoneal e na segunda fase do teste de nocicepÃÃo induzida pela injeÃÃo intraplantar de formalina. O (-)-a-bisabolol nÃo demonstrou atividade no modelo de nocicepÃÃo tÃrmica da placa quente. Esses achados sugerem que a aÃÃo antinociceptiva do (-)- a-bisabolol nÃo estÃ ligada a mecanismos centrais e deve estar relacionada com o processo inflamatÃrio. Nos modelos de edema de pata induzidos por carragenina e dextrano os animais tratados com (-)-a-bisabolol exibiram edemas menores em comparaÃÃo com os animais tratados apenas com veÃculo. (-)-a-bisabolol foi capaz de diminuir os edemas de pata induzidos por 5-HT, mas nÃo os edemas induzidos por histamina, assim, pode-se relacionar a atividade anti-inflamatÃria do (-)-a-bisabolol a sua interferÃncia na aÃÃo/liberaÃÃo ou na sÃntese/metabolismo da 5-HT. O (-)-a-bisabolol mostrou ter atividade gastroprotetoras frente Ãs lesÃes gÃstricas induzidas por etanol absoluto ou indometacina. O mecanismo dessa aÃÃo foi testado farmacologicamente, realizando prÃ-tratamentos com L-NAME, Glibenclamida e Indometacina. Estes experimentos demonstraram que a aÃÃo gastroprotetora do (-)-a- bisabolol parece nÃo envolver o Ãxido nÃtrico, os canais de potÃssio ATP-dependentes ou a sÃntese de prostaglandinas. Por outro lado, a quantificaÃÃo de GSH nos tecidos gÃstricos dos animais nÃo lesionados e lesionados por etanol ou indometacina mostraram que o tratamento com (-)-a-bisabolol atenua o decrÃscimo de GSH associado as lesÃes pelos agentes lesivos, mas nÃo aumenta a sua quantidade nos estÃmagos dos animais nÃo tratados com etanol ou indometacina. Dessa forma o (-)-a-bisabolol aumenta a disponibilidade de GSH no tecido gÃstrico, possuindo aÃÃo antioxidante in vivo, o que nos permite associar esse achado a sua aÃÃo gastroprotetora.
(-)-a-bisabolol, a sesquiterpenic Ãlcool, is commonly obtained from Matricaria chamomilla and from species of Vanillosmopsis, it was tested in animal standardized models of nociception, inflamation and gastric ulcer in mice. In this assays, (-)-a-bisabolol was used in the doses of 25 and 50 mg/Kg in the models of nociception and 100 and 200 mg/Kg in the models of inflamatiom and gastric ulcers, administered by via oral. (-)-a-bisabolol demonstrated to have an antinociceptive activity in the models of visceral nociception induced by intraperitoneal acetic acid and in the second phase of the test nociception was induced by intraplantar administration of formaline. (-)-a-bisabolol did not demonstrate activity in the thermal nociception model of hot plate. These findings suggests that the antinociceptive action of (-)-a-bisabolol is not linked to central mechanisms and may be related with pre inflamatory process. In the models of paw oedema induced by carragenine and dextran the animals treated with (-)-a-bisabolol showed smaller oedemas as compared to animals treated only with the vehicle. (-)-a-bisabolol was capable to reduce the paw oedemas induced by 5- HT, but not the oedema induced by histamine, so it could relate the antiinflamatory activity of (-)-a-bisabolol to the interference in the action/liberation or in the systesis/metabolism of 5- HT. (-)-a-bisabolol demostrated having gastroprotective activity in the absolute ethanol and indomethacin-induced gastric lesions. The mechanism of this action was pharmacologicaly tested, doing pre-treatments with L-NAME, Glibenclamide and Indomethacin. These experiments demonstrated that tha gastroprotective action of (-)-a-bisabolol seems not to be involved the nitric oxide, potassium channels ATP-dependents or the sysntesis of prostaglandines. By the way, the quantification of GSH in the gastric tissues of not lesioned animals e lesionated by ethanol or indomethacin showed that the treatment with (-)-a- bisabolol atenuate the decrease of GSH associated with the lesive agents, but it did not increase its levels in the animals that not recieve ethanol or indomethacin. This way (-)-a- bisabolol increase the disponibility of GSH in the gastric tissue, having in vivo antioxidant activity, that allows us to associate this finding to its gastroprotective action.

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28

Cornwell, Charles Peter. "Aspects of the chemistry and origins of terpenes from Australian myrtaceae /". Richmond, N.S.W. : University of Western Sydney, Hawkesbury, 1999. http://library.uws.edu.au/adt-NUWS/public/adt-NUWS20030528.164427/index.html.

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29

Kuo, David Liang. "The use of camphor in sesquiterpenoid synthesis". Thesis, University of British Columbia, 1987. http://hdl.handle.net/2429/28847.

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This thesis, entitled "The use of camphor in sesquiter-penoid synthesis", consists of three chapters. Chapter One describes the conversion of (+)-8-bromocamphor (42) into a chiral dimethyl-acetal enolsilyl ether (105) that undergoes facile TiCl₄₋ promoted intramolecular cyclisation to provide tricyclic intermediates (195a,b), which after a series of functional group interconversions and the introduction of the gem-dimethyl group, leads to the first enantiospecific total synthesis of (+)-longiborneol (59) (ca. 13% in 21 steps from ( + )-camphor (26)). Oxidation of (+)-longiborneol (59) provides (+)-longicamphor (83), which was converted into (+)-longi-isoborneol (89) by reduction. Subsequent treatment with of (+)-longiisoborneol (89) with MsCl, 4-DMAP, and pyridine, reveals (+)-longifolene (61) (ca. 52% in 3 steps from (59)). Two other major attempts were also carried out prior to the successful synthesis of (59) and (61). Triene acetates (103a,b) were synthesised (ca. 8% in 10 steps from (+)-camphor (26)), but failed to undergo the intramolecular Diels-Alder reaction. In addition, (+)-campherenone (151) was also prepared (ca. 28% in 9 steps from (+)-camphor (26)), and both (151) and its derivatives (170), and (104) undergo SnCl₄-promoted intermolecular tertiary ∝-alkylation reaction to provide dimers (169a,b). Chapter Two describes two synthetic approaches to albene (221) which involves an intramolecular ene reaction, or an intramolecular free radical cyclisation reaction. A new enantiospecific synthesis route to (+)-β-santalene (259) (ca. 78% in 2 steps from (+)-campherenone (151)) is illustrated, however, (+)-β-santalene failed to undergo the intramolecular ene reaction to provide olefin (261). In addition, bromo-olefin (260) is also prepared (ca. 59% in 14 steps from (+)-camphor (26)), but cyclises in a 6-exo-trig mode in the intramolecular free radical cyclisation reaction to provide methyl ether (331). Chapter Three describes an evaluation of the potential use of (+)-5,6-dehydrocamphor (323) as a chiral synthon in the synthesis of the A,B ring system (cf. 329) of several classes of terpenoid. (+)-5,6-dehydrocamphor (323) was prepared from (-)-endo-3-bromocamphor (41) in two steps, and which is then converted to bicyclic enones (368a,b, 369a,b, 376a,b) by a sequence in which the key reaction was an anionic oxy-Cope rearrangement. Bicyclic enones (368a,b) were converted to tricyclic ketals (385a,b), but attempts to convert this compound to an angularly methylated intermediate (434) were unsuccessful. Furthermore, 1,5-dienols (409a,b), synthesised from (323) in ca. 50% yield, failed to undergo an anionic oxy-Cope rearrangement to provide bicyclic ketones (410a,b). Alternative ways of constructing an angular methyl group into the C(10) position in bicyclic enones (369a,b, or 376a,b) are currently being investigated in our laboratory. In addition, bicyclic ketones (373a,b) could serve as key intermediates in an enantiospecific synthesis of spirodysin (421), and indirectly to the synthesis of furodysin (422), and furodysinin (423). [Formula Omitted]
Science, Faculty of
Chemistry, Department of
Graduate

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30

Clase, Juha Andrew. "Further investigations on the use of camphor in terpenoid synthesis". Thesis, University of British Columbia, 1990. http://hdl.handle.net/2429/30990.

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The cyclopentyl compounds 113,114, and 115 and their enantiomers ent-113, ent-114 and ent-115 represent valuable chiral building blocks for the synthesis of steroids and triterpenoids. These compounds are readily available in chiral form from the Grob type cleavage of (+)-9,10-dibromocamphor (120) or (-)-9,10-dibromocamphor (ent-120) respectively. The hydroxyacid 114 was transformed into the bicyclic ester 153 in a series of seven steps, the key step of which was the intramolecular Friedel-Crafts acylation of the methylene diacid 161. The ester 153 is considered to be a valuable steroidal CD synthon, incorporating functionality for introduction of both the A and B rings and a C(20) sidechain. It was demonstrated that it was possible to alkylate the ketal 169 stereospecifically and convert the product to the enone 168 in which the steroidal C(20) centre has been established with the natural R configuration. In a second approach to steroidal precursors, the hydroxydiene 299 was prepared in six steps from the bromoester 115. The enantiomer of 299, (ent-299) represents a potentially useful intermediate in the intramolecular Diels-Alder route to A-aromatic steroids such as estrone (3), and would be readily available from ent-115. The bromoester ent-115 and (+)-5,6-dehydrocamphor (223) were combined in a synthesis of the tetracyclic hydroxyenone 252, the key step of which was the anionic oxy-Cope rearrangement of the 5,6-dehydrocamphor derivative 241. The structure 252 is considered to represent the basic tetracyclic skeleton of euphane and apo-euphane triterpenoids, and posesses suitable functionality for incorporation of methyl groups at C(10) and C(8) (apo-euphane) or C(14) (euphane), as well as oxygen substituents at those centres at which it is commonly found in the triterpenoids. Finally, a mechanistic investigation of the rearrangement of 2-methylenebornane (314) to 4-methylisobornyl acetate (315) is described. The methyl region of the ¹H NMR spectrum of 4-methylcamphor (308), derived from 314, was unambiguously assigned by a series of NMR experiments and used to trace the fate of deuterium when 2-(dideuteriomethylene)bornane (323) and 8-deuterio-2-methylenebornane (324) were subjected to the rearrangement conditions. [formulas omitted]
Science, Faculty of
Chemistry, Department of
Graduate

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31

Sowers, Ryan Arthur. "A biomimetic approach to the synthesis of sarcoglane". Click here for download, 2009. http://proquest.umi.com/pqdweb?did=1698507651&sid=1&Fmt=2&clientId=3260&RQT=309&VName=PQD.

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32

Martins, Mariana Provedel. "Resolução cinética de haloidrinas racêmicas com a lipase B de Candida antarctica e biotransformação de produtos naturais por micro-organismos". Universidade de São Paulo, 2012. http://www.teses.usp.br/teses/disponiveis/75/75134/tde-20032013-101611/.

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Neste trabalho foram realizadas as resoluções cinéticas das haloidrinas racêmicas (RS)-1-benziloxi-3-cloropropan-2-ol (4a), (RS)-1-benziloxi-3-bromopropan-2-ol (4b), (RS)-1-cloro-3-(4-metoxifenoxi)propan-2-ol (5a), (RS)-1-bromo-3-(4-metoxifenoxi)propan-2-ol (5b), (RS)-1-aliloxi-3-cloro-propan-2-ol (6a) e (RS)-1-aliloxi-3-bromo-propan-2-ol (6b) empregando-se a lipase comercial de Candida antarctica CALB como catalisador e acetato de vinila como agente acilante. As razões enantioméricas das resoluções cinéticas foram determinadas com o intuito de avaliar a influência dos grupos substituintes halogênios presentes nas haloidrinas na eficiência das resoluções cinéticas desses substratos. Os valores de razão enantiomérica obtidos foram: E = 5,6, 4a; E = 4,3, 4b; E = 98, 5a; E = 6,6, 5b; E = 20, 6a; E = 5,8, 6b. Assim, somente as resoluções cinéticas das cloroidrinas 5a e 6a apresentaram valores de E característicos de resoluções eficientes, fornecendo os produtos (R)-1-cloro-3-(4-metoxifenoxi)propan-2-ol 5a com rendimento de 46% e ee = 40%; (S)-acetato de 1-cloro-3-(4-metoxifenoxi)propan-2-ila 8a com rendimento de 40% e ee = 97%; (R)-1-aliloxi-3-cloro-propan-2-ol (R)-6a com rendimento de 45% e ee = 72% e (S)-acetato de 1-aliloxi-3-cloro-propan-2-ila (S)-9a com rendimento de 41% e ee = 81%. Realizou-se também uma triagem com os fungos de origem marinha Bostryospharia sp. Br09, Eutypella sp. Br23, Hidropisphaera sp. Br27, Xylaria sp. Br61, Aspergillus sydowii Ce19, Aspergillus sydowii Ce15, Penicillium raistriicki Ce16, Penicillium oxalicum F30 e Penicillium citrinum F53 frente aos produtos naturais sclareol, ambrox e sclareolide, a fim de selecionar os micro-organismos capazes de promover reações de bio-oxidação nesses substratos. Os metabólitos hidroxilados obtidos nas reações de biotransformação foram: 3β-hidroxi-ambrox 10a (rendimentos de 17% e 11%, com os fungos Br09 e Br23, respectivamente); 1β-hidroxi-ambrox 10b (rendimento de 14% com o fungo Ce19); 3β-hidroxi-sclareol 11a (rendimentos de 31%, 69% e 55%, com os fungos Br61, Br09 e Br23, respectivamente); 18-hidroxi-sclareol 11b (rendimento de 10% com o fungo Br61); 3β-hidroxi-sclareolide 12a (rendimentos de 34% e 7%, com os fungos Br09 e Br23, respectivamente). Realizou-se também um estudo utilizando-se três meios de cultura líquidos (meio sintético, meio YM e meio PDB) para a reação de biotransformação do sclareol 11 no composto ambradiol 13 com a levedura Hyphozyma roseonigra. Observou-se que a reação com o meio de cultura líquido PDB apresentou os melhores resultados, com uma grande eficiência na conversão do substrato no produto de interesse, o qual foi obtido com um rendimento de 82%. Esta reação foi realizada também através de um processo fermentativo conduzido em biorreator, apresentando bons resultados quanto à conversão da reação, porém com a desvantagem do alto custo do meio de cultura PDB, o que dificulta a realização deste processo fermentativo em larga escala.
In this work we performed kinetic resolutions of the racemic halohydrins (RS)-1-benzyloxy-3-chloropropan-2-ol (4a), (RS)-1-benzyloxy-3-bromopropan-2-ol (4b), (RS)-1-chloro-3-(4-methoxyphenoxy)propan-2-ol (5a), (RS)-1-bromo-3-(4-methoxyphenoxy)propan-2-ol (5b), (RS)-1-allyloxy-3-chloro-propan-2-ol (6a) and (RS)-1-allyloxy-3-bromo-propan-2-ol (6b) using the lipase from Candida antarctica CALB as catalyst and vinyl acetate as acylating agent. The enantiomeric ratios of the kinetic resolutions were determined in order to evaluate the influence of the halogen substituents present in halohydrins in the efficiency of the kinetic resolutions of these substrates. The enantiomeric ratio values obtained were: E = 5.6, 4a; E = 4.3, 4b; E = 98, 5a; E = 6.6, 5b; E = 20, 6a; E = 5.8, 6b. Thus, only the kinetic resolutions of the chlorohydrins 5a and 6a showed characteristic values of E of efficient resolutions, providing the products (R)-1-chloro-3-(4-methoxyphenoxy)propan-2-ol 5a with 46% yield and ee = 40%; (S)-1-chloro-3-(4-methoxyphenoxy)propan-2-yl acetate 8a with 40% yield and ee = 97%; (R)-1-allyloxy-3-chloro-propan-2-ol (R)-6a with 45% yield and ee = 72% and (S)-1-allyloxy-3-chloro-propan-2-yl acetate (S)-9a with 41% yield and ee = 81%. We also performed a screening with the marine fungi Bostryospharia sp. Br09, Eutypella sp. Br23, Hidropisphaera sp. Br27, Xylaria sp. Br61, Aspergillus sydowii Ce19, Aspergillus sydowii Ce15, Penicillium raistriicki Ce16, Penicillium oxalicum F30 and Penicillium citrinum F53 using the natural products ambrox, sclareol and sclareolide in order to select the microorganisms capable of promoting bio-oxidation reactions of these substrates. The hydroxylated metabolites obtained from the biotransformation reactions were: 3β-hydroxy-ambrox 10a (17% and 11% yield with Br09 and Br23, respectively); 1β-hydroxy-ambrox 10b (14% yield with Ce19); 3β-hydroxy-sclareol 11a (31%, 69% and 55% yield with Br61, Br23 and Br09, respectively); 18-hydroxy-sclareol 11b (10% yield with Br61); 3β-hydroxy-sclareolide 12a (34% and 7% yields with Br09 Br23, respectively). We also performed a study employing three liquid culture media (synthetic, YM and PDB media) for the biotransformation reaction of sclareol 11 into ambradiol 13 using Hyphozyma roseonigra as catalyst. The reaction with the liquid culture media PDB showed the best results, with a high efficiency in the conversion of the substrate into the desired product, which was obtained in 82% yield. This reaction was also performed using a fermentation process conducted in a bioreactor, with good results, however with the disadvantage of the high cost of culture media PDB, which hinders the performance of this large-scale fermentation.

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Medeiros, Heloisa Helena Berredo Reis de 1979. "Fracionamento do óleo de laranja utilizando um sistema híbrido de evaporação". [s.n.], 2014. http://repositorio.unicamp.br/jspui/handle/REPOSIP/266076.

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Orientadores: Maria Regina Wolf Maciel, Patrícia Fazzio Martins Martinez
Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Química
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Resumo: O Brasil é o maior produtor mundial de laranjas, sendo também considerado um grande produtor e exportador mundial do óleo de laranja. Óleo de laranja doce, um importante subproduto gerado a partir da produção de suco de laranja, é constituído por aproximadamente 400 compostos, dentre os quais, destacam-se as classes de terpenos, oxigenados e flavonoides. Essas classes de compostos apresentam elevado potencial para as indústrias alimentícia, cosmética, farmacêutica e química. O fracionamento deste óleo tem recebido grande atenção da comunidade científica e industrial devido à instabilidade de determinados componentes. Neste trabalho, a separação e concentração dos componentes limoneno, valenceno, decanal, tangeritina e nobiletina foram realizadas utilizando-se um sistema híbrido de evaporação a pressões de 2 e 20 mbar. Três frações resultantes do sistema foram obtidas, são elas: destilado, lateral e resíduo. Através de um planejamento experimental do tipo composto central, observou-se que a temperatura do evaporador é a variável que tem maior influência nos resultados. As maiores concentrações de limoneno foram encontradas nas frações destilado e lateral, chegando-se à concentração de 99,5%. Os compostos valenceno e decanal não foram identificados na fração destilado e suas maiores concentrações estão presentes na fração resíduo. Comportamento semelhante foi observado para os flavonoides tangeritina e nobiletina, os quais foram concentrados na fração resíduo. De acordo com os resultados obtidos neste trabalho, é promissor separar e concentrar os compostos citados acima presentes no óleo de laranja doce utilizando um sistema híbrido de evaporação
Abstract: Brazil is the world¿s largest orange producer, and is also considered a major producer and exporter of orange oil. Sweet orange oil, an important by-product generated from the production of orange juice, consists of approximately 400 compounds, among which stand out the classes of terpenes, oxygenated and flavonoids. These classes of compounds have high potential for the food, cosmetic, pharmaceutical and chemical industries. Fractionation of this oil has received great attention of the scientific and industrial community due to the intability of certain components. In this work, the separation and concentration of the components limonene, valencene, decanal, tangeritin and nobiletin were performed using a hybrid system of evaporation at pressures from 2 and 20 mbar. Three fractions of the resulting system were obtained, they are: distillate, side and residue. Through an experimental design of the central composite type, it is observed that the evaporator temperature is the variable that has the greatest influence on the results. The highest concentrations of limonene were found in the distillate and side fractions, reaching to the concentration of 99.5%. The valencene and decanal compounds were not identified in the distillate fraction and its highest concentrations are present in the residue fraction. Similar behavior eas observed for tangeritin and nobiletin flavonoids, which are concentrated in the residue fraction. According to the results obtained in this study it is promising to separate and concentrate the compounds mentioned above present in sweet orange oil using a hybrid system of evaporation
Doutorado
Desenvolvimento de Processos Químicos
Doutora em Engenharia Quimica

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34

Aarão, Serra Antonio. "Approches synthétiques de terpenes (+)-acide hirsutique C, (+)-brasilenol et (-)-taxol /". Grenoble 2 : ANRT, 1987. http://catalogue.bnf.fr/ark:/12148/cb37602017k.

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35

Govande, C. A. "Development of synthetic methodologies towards terpenes: heritol, heritianin and pseudopterosins". Thesis(Ph.D.), CSIR-National Chemical Laboratory, Pune, 1997. http://dspace.ncl.res.in:8080/xmlui/handle/20.500.12252/3359.

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36

Romero, Adriano Lopes. "Contribuição ao conhecimento quimico do oleo-resina de copaiba : configuração absoluta de terpenos". [s.n.], 2007. http://repositorio.unicamp.br/jspui/handle/REPOSIP/249068.

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Abstract (sommario):

Orientador: Paulo Mitsuo Imamura
Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Quimica
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Resumo: óleo-resina de copaíba comercial é um exudado do tronco de diversas espécies do gênero Copaifera (Caesalpinoideae, Leguminosae). Esse óleo é utilizado na medicina popular como cicatrizante, antiinflamatório, no tratamento de bronquites e doenças de pele, assim como na indústria cosméstica como fixador para perfumes e como solvente para tintas e vernizes. Apesar de existir extensa literatura sobre o óleo de copaíba e alguns artigos recentes relatarem o isolamento de novos compostos, muitas das configurações absolutas permanecem indeterminadas. Diante desse fato este trabalho teve como objetivo, isolar os constituintes químicos do óleo de copaíba comercial para caracterização e efetuar a determinação das configurações absolutas dos mesmos. O óleo-resina de copaíba foi submetido a uma extração ácido-base fornecendo duas frações: Fração Neutra (81,7%) e Fração Ácida (18,3%). O estudo da fração neutra permitiu o isolamento de onze sesquiterpenos, sendo dois deles relatados pela primeira vez neste material {(-)-7(11)-selinen-4-ol e (-)-torreyol}; três dinorlabdanos, sendo um inédito como produto natural; e o clerodano 7- acetoxibacchotricuneatina D. A configuração absoluta dos dinorlabdanos foram determinadas pela síntese a partir do ácido (-)-3-hidroxi-copálico e a estereoquímica do C-13 dos álcoois dinorlabdânicos foi estabelecida pela aplicação do método de Mosher modificado. Da fração ácida foram isolados três diterpenos ácidos (copálico, 3-acetoxi-copálico, 3-hidróxicopálico). Além disso, após tratamento de uma amostra da fração ácida com diazometano e purificação por cromatografia em coluna de sílica gel, foram isolados oito diterpenos, sendo um destes inédito (3,19- diidróxi-copalato de metila) e dois terpenos raros (o guamaato de dimetila e o 4-hidroperóxido-18-norcopalato de metila)
Abstract: The commercial copaiba oleoresin is an exuded obtained from the trunk of many species of the Copaifera genus (Caesalpinoideae, Leguminosae). This oil is used in the popular medicine as cicatrizant, anti-inflammatory, in the treatment of bronchitis and for skin diseases, and also in the cosmetic industry as fixative of the perfumes and as solvent for inks and varnishes. Although there are an extensive report concerning the composition of copaíba oil in the literature and some recent papers report the isolation of new compounds, the absolute configuration of many of then remains unknown. Thus, this work had as objective to isolate the compounds of the commercial copaíba oleoresin in order to characterize and determine the absolute configurations. Thus, the copaíba oleoresin was submitted to acid-base extraction supplying two fractions: Neutral Fraction (81.7%) and Acidic Fraction (18.3%). The study of the neutral fraction allowed the isolation of eleven sesquiterpenes, where two of then were not yet reported previously in this material {(-)-7(11)-selinen-4-ol and (-)-torreyol}; one new dinorlabdane and two known dinorlabdane and the diterpene clerodane 7-acetoxibacchotricuneatine D. The absolute configuration of dinorlabdanes was established by synthesis starting from (-)-3-hydroxycopalic acid and the stereochemistry of the C-13 carbon was determined using Mosher¿s modified method. From the acid fraction were isolated three diterpenic acids (copalic, 3-acetoxy-copalic, 3-hydroxy-copalic). Besides, after treatment of a sample of acidic fraction with diazomethane and purification through SiO2 gel column chromatography, a new compound (methyl 3,19-dihydroxy-copalate) was isolated along with two rare diterpenes (dimethyl guamaate and methyl 4-hydroperoxy-18- norcopalate) and five known diterpenes
Mestrado
Quimica Organica
Mestre em Química

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37

Pommer, Linda. "Oxidation of terpenes in indoor environments : A study of influencing factors". Doctoral thesis, Umeå University, Ecology and Environmental Science, 2003. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-29.

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In this thesis the oxidation of monoterpenes by O3 and NO2 and factors that influenced the oxidation were studied. In the environment both ozone (O3) and nitrogen dioxide (NO2) are present as oxidising gases, which causes sampling artefacts when using Tenax TA as an adsorbent to sample organic compounds in the air. A scrubber was developed to remove O3 and NO2 prior to the sampling tube, and artefacts during sampling were minimised when using the scrubber. The main organic compounds sampled in this thesis were two monoterpenes, alfa-pinene and delta-3-carene, due to their presence in both indoor and outdoor air. The recovery of the monoterpenes through the scrubber varied between 75-97% at relative humidities of 15-75%.

The reactions of alfa-pinene and delta-3-carene with O 3, NO2 and nitric oxide (NO) at different relative humidities (RHs) and reaction times were studied in a dark reaction chamber. The experiments were planned and performed according to an experimental design were the factors influencing the reaction (O3, NO2, NO, RH and reaction times) were varied between high and low levels. In the experiments up to 13% of the monoterpenes reacted when O3, NO2, and reaction time were at high levels, and NO, and RH were at low levels. In the evaluation eight and seven factors (including both single and interaction factors) were found to influence the amount of alfa-pinene and delta-3-carene reacted, respectively. The three most influencing factors for both of the monoterpenes were the O 3 level, the reaction time, and the RH. Increased O3 level and reaction time increased the amount of monoterpene reacted, and increased RH decreased the amount reacted.

A theoretical model of the reactions occurring in the reaction chamber was created. The amount of monoterpene reacted at different initial settings of O3, NO2, and NO were calculated, as well as the influence of different reaction pathways, and the concentrations of O3 and NO2, and NO at specific reaction times. The results of the theoretical model were that the reactivity of the gas mixture towards alfa-pinene and delta-3-carene was underestimated. But, the calculated concentrations of O3, NO2, and NO in the theoretical model were found to correspond to a high degree with experimental results performed under similar conditions. The possible associations between organic compounds in indoor air, building variables and the presence of sick building syndrome were studied using principal component analysis. The most complex model was able to separate 71% of the “sick” buildings from the “healthy” buildings. The most important variables that separated the “sick” buildings from the “healthy” buildings were a more frequent occurrence or a higher concentration of compounds with shorter retention times in the “sick” buildings.

The outcome of this thesis could be summarised as follows;

-

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38

Hagreen, Matthew Edward. "Physical properties of atmospheric aerosol products from the ozonolysis of terpenes". Thesis, University of Reading, 2018. http://centaur.reading.ac.uk/78954/.

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This thesis describes experiments carried out to understand the formation of particles in the reactions of ozone with terpenes, processes that are important in atmospheric chemistry and have an impact on climate change. The main instrument used to study the reactions was a Scanning Mobility Particle Sizer (SMPS), with some experiments using an Electrical Low Pressure Impactor (ELPI+). The SMPS instrument was used first to study the evolution of aerosol particles formed from the ozonolysis of α-pinene. A strong dependence on OH scavenger, and the [RO2] / [HO2] ratios produced by each, was observed. The effect of relative humidity on the formed aerosol was investigated, and was found to influence both number and size of the particles formed. The relationship between aerosol mass concentration and mass yield was extended beyond the range reported in the literature. A rate constant for the α-pinene ozonolysis was calculated from the aerosol mass evolution, k = 1.05 ± 0.11 × 10-16 cm3 molecule-1 s -1 , which agrees well with the literature. Preliminary studies using the ELPI+ instrument were undertaken, and some successful experiments suggested that physical state of the aerosol is independent of relative humidity across the range studied. An enone derivative of α-pinene was synthesised to allow for study of one of the αpinene Criegee intermediates (CIs) in isolation. A rate constant for its reaction with ozone of k = 4.3 ± 0.9 × 10-17 cm3 molecule-1 s -1 was determined. Enone mass yields were 5–7 % lower than those of α-pinene, suggesting that products of CI 2 (enal) contribute more to the total aerosol mass than those of CI 1 (enone). The data suggest that CI 2 is primarily responsible for particle nucleation, and both CIs contribute significantly to their growth. The ozonolysis of α-terpinene was investigated using both static chamber experiments and an atmospheric pressure flow tube. This allowed for calculation of upper and lower bounds for the rate constant. The upper bound, k = 1.6 ± 0.29 × 10-14 cm3 molecule-1 s -1 , is in agreement with the literature. Increasing ozone concentration was noted to have a particularly large impact on the mass of aerosol produced. Mass yields were found to be much higher than for α-pinene, suggesting an array of very low volatility products. The effect of relative humidity on the initial stages of aerosol formation was studied using the flow tube, and a small effect on the particle size distribution was noted.

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39

Bråred, Christensson Johanna. "Clinical and experimental studies on oxidized fragrance terpenes as contact allergens /". Göteborg : Department of Dermatology and Venereology, Sahlgrenska University Hospital, Institute of Clinical Sciences at Sahlgrenska Academy, University of Gothenburg, 2009. http://hdl.handle.net/2077/19052.

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40

Adate, P. A. "Novel organocatalytic asymmetric approach towards prismatomerin type Iridoid class of terpenes". Thesis(Ph.D.), CSIR-National Chemical Laboratory, Pune, 2013. http://dspace.ncl.res.in:8080/xmlui/handle/20.500.12252/2175.

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41

Munro, Thomas Anthony. "The chemistry of Salvia divinorum /". Connect to thesis, 2006. http://eprints.unimelb.edu.au/archive/0002327.

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42

Augustyn, WA, BM Botha, S. Combrinck e Plooy SW Du. "Correlation of volatile profiles of twenty mango cultivars with their susceptibilities to mango gall fly infestation". Elsevier, 2010. http://encore.tut.ac.za/iii/cpro/DigitalItemViewPage.external?sp=1001217.

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Abstract Mango gall fly (Procontarinia matteiana) is an orchard pest that parasitises flush leaves of mango and serious outbreaks may result in reduced fruit yield. The trigger for infestation is unknown, but terpenes emitted by the leaves appear to play a role in attraction. Metabolic profiles of three mango cultivars of varying susceptibility to mango gall fly attack were obtained by headspace profiling using GC-FID and GC-MS analysis. Chemometric models constructed from the data revealed that three terpenes, α- and β-pinene and camphene could be useful as biomarkers for susceptibility. Headspace profiles of twenty other cultivars, naturally exposed to gall fly, were obtained in the same way. Susceptibility or resistance of these cultivars was predicted using the developed orthogonal partial least squares model. Predictive outcomes were thereafter verified by visual examination of the leaves to detect gall formation, an indication of gall fly infestation. The model was found to predict the susceptibility or resistance of 90% of the cultivars accurately. This finding indicates the contributory role of the three terpene biomarkers in mango gall fly interaction and may direct future studies to determine their inter-relationship.

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43

BRICHE, MORICEAU ANNE. "Intoxication terpenique". Angers, 1990. http://www.theses.fr/1990ANGE1023.

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44

Leung, Lai-to. "Studies toward the total synthesis of C14-oxygenated dolastane natural products". Click to view the E-thesis via HKUTO, 2008. http://sunzi.lib.hku.hk/hkuto/record/B41508841.

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45

Ye, Xiangyang. "I. Enantioselective total synthesis of ( - )-triptolide : II. synthesis of triptolide analogs /". Hong Kong : University of Hong Kong, 1999. http://sunzi.lib.hku.hk/hkuto/record.jsp?B20896918.

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46

Greenhagen, Bryan T. "Origins of isoprenoid diversity a study of structure-function relationships in sesquiterpene systems /". Lexington, Ky. : [University of Kentucky Libraries], 2003. http://lib.uky.edu/ETD/ukyplph2003d00093/Greenhagen.pdf.

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Thesis (Ph. D.)--University of Kentucky, 2003.
Title from document title page (viewed onJune 1, 2004). Document formatted into pages; contains x, 145 p. : ill. Includes abstract and vita. Includes bibliographical references (p. 126-143).

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47

Araújo, Ana Lucia Santos de Matos. "Estudos sobre a síntese de microbiotol". Universidade de São Paulo, 1999. http://www.teses.usp.br/teses/disponiveis/59/59132/tde-15102002-163623/.

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Neste trabalho descrevemos vários estudos sintéticos realizados com o objetivo de desenvolver um método para a preparação de Microbiotol (1). A estratégia planejada consistiu em preparar o anel ciclopentano que constitui a metade esquerda da fórmula de (1) acima por contração de anel de isoforona (58), e depois juntar uma cadeia aberta que seria posteriormente ciclizada para formar o segundo anel. A contração do anel da isoforona (58) foi realizada de acordo com as reações a seguir: Os compostos de fórmula geral (85) apresenta considerável congestionamento estérico e resistem fortemente à adição de nucleófilos. Neste trabalho desenvolvemos apenas estudos de adição de derivados de levulinato de metila, este mesmo apresentando problemas de reatividade devido a problemas estéricos, e mostramos que este não é o caminho adequado para adicionar um nucleófilo aos compostos (85).
In this work we describe several synthetic studies realized with the purpose of developing a method for the preparation of Microbiotol (1). Our synthetic strategy consisted of preparing the ciclopentane ring which is the left moiety of structure (1) by a ring contraction , starting from isophorone (58), and then add an open chain which would be cyclized to for second ring. The ring contraction was realised according to the following steps. The compounds of general structure (58) have a considerable steric hindrance and are strongly resistant to the addition of a nucleophile. In this work we used only derivatives of methyl levulinate as nucleophiles ; these substrates are themselves sterically hindered, and we showed that this is not the appropriate method to add a nucleophile to compounds (85).

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48

Maróstica, Junior Mário Roberto 1980. "Biotransformação de terpenos para a produção de compostos de aroma e funcionais". [s.n.], 2006. http://repositorio.unicamp.br/jspui/handle/REPOSIP/256710.

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Orientador: Glaucia Maria Pastore
Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos
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Resumo: Este trabalho teve por objetivos o estudo da biotransformação de terpenos e avaliação de suas propriedades biológicas. A biotransformação de limoneno foi realizada por uma linhagem de Fusarium oxysporum cultivada em manipueira e transferida para meio mineral, sendo o óleo essencial de laranja, um resíduo da indústria do suco de laranja, a fonte do limoneno. Rendimentos da ordem de 450 mg/L de a-terpineol, o principal produto obtido, foram alcançados. Da mesma forma, a biotransformação do citronelol foi conduzida por uma linhagem de Penicillium sp. cultivada em manipueira e transferida para meio mineral. O principal produto obtido foi o cis-óxido de rosa em concentrações da ordem de 70 mg/L. A seleção de microrganismos biotransformadores de limoneno (cuja fonte foi óleo essencial de laranja) a- e b-pinenos (cuja fonte foi terebentina, resíduo industrial da indústria de papel) foi realizada por microextração em fase sólida (MEFS). A técnica mostrou-se eficaz para a recuperação de voláteis presentes no 'heapspace¿ de culturas esporuladas de superfície para a biotransformação. Os microrganismos selecionados por MEFS foram submetidos à biotransformação em cultura líquida e produção da ordem de 50 mg/L de verbenol por Mucor sp. 2276 e 70 mg/L de verbenona resultaram da biotransformação de a- e b-pinenos. Aspergillus sp. 2357 e Penicillium sp. 2360 produziram aproximadamente 90 e 10 mg/L de a-terpineol e álcool perílico respectivamente. A biotransformação de a-farneseno por linhagens de Aspergillus niger gerou compostos nunca relatados anteriormente na literatura. Quatro produtos principais foram obtidos. Apenas um composto pôde ser identificado por meio de CG-EM como 6-OH-farneseno. Análises de CG-olfatometria descreveram 6-OH-farneseno como aroma cítrico impactante. Estudos 'in vitro¿ e 'in vivo¿ com extrato da biotransformação de limoneno por Fusarium oxysporum e com padrões de monoterpenos revelaram o potencial desses compostos em atuarem como antioxidantes, gerando uma possibilidade para esses compostos serem utilizados industrialmente como aromas funcionais
Abstract: The biotransformation of terpenes and their functional properties were investigated in this study. The biotransformation of limonene was done by a Fusarium oxysporum strain grown in cassava waste water and transferred into a mineral medium for biotransformation. The limonene source was an orange essential oil from a orange juice industry. The main biotransformation product was a-terpineol, reaching around 450 mg/L. Similarly, biotransformation of citronellol was conducted by a Penicillium sp. strain grown also in cassava waste water and transferred into a mineral medium. The main product was cis-rose oxide, reaching concentrations higher than 70 mg/L. The screening of microrganisms for biotransformation of limonene (from orange essential oil) and a-, b-pinenes (from turpentine oil, residue from pulp industry) was done by solid phase microextraction (SPME). The technique was effective for the recovery of the volatiles from the headspace of sporulated surface biotransformation cultures. Liquid culture biotransformation experiments performed with the SPME screened strains resulted in the production of 50 mg/L of verbenol by Mucor sp. 2276 and 70 mg/L of verbenone form a-, b-pinenes and 90 mg/L of a-terpineol by Aspergillus sp. 2357 and 10 mg/L of perillyl alcohol by Penicillium sp. 2360. The biotransformation of a-farnesene by Aspergillus niger strains resulted in compounds never described in the literature before. Four main new compounds were obtained. Only one of them could be identified by GC-MS as 6-OH-farnesene. CG-O experiments revealed the impactant citrus aroma of 6-OH-farnesene. 'In vitro¿ and 'in vivo¿ experiments with the limonene biotransformation extract by Fusarium oxysporum and with the monoterpene standards present in the extract revealed the antioxidant potential of these compounds, which open a new perspective for the utilization of these compounds as functional aroma compounds
Doutorado
Doutor em Engenharia de Alimentos

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49

Camargos, Heverton Silva de. "Estudos de membranas modelo e efeitos de terpenos em membranas de leishmania por ressonância paramagnética eletrônica". Universidade Federal de Goiás, 2013. http://repositorio.bc.ufg.br/tede/handle/tede/3559.

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Outras
Electron paramagnetic resonance (EPR) spectroscopy of spin labels was used to study the main structural accommodations of environment-sensitive probes in the bilayers of saturated phosphatidylcholines with acyl chains lengths ranging from 16 to 22 carbon atoms. The more detailed analysis were made on the spin probe 5-doxyl methyl stearate (5-DMS) whose EPR spectra allowed to identify two distinct spectral components in thermodynamic equilibrium at temperatures below and above the main phase transition. The EPR spectroscopy distinguishes two components associating lower motion with higher polarity (denoted component 1) and higher motion with lower polarity (component 2), which may be assigned to one shallow (more rigid structure) and one deep population of spin probe, respectively. At temperatures until 22◦C only one spectral component can be noted in the spectra whereas at 30◦C the component 1 coexists with an appreciable fraction of component 2. In the liquid-crystalline phase the 5-MSL showed two spectral components for all studied lipids in the entire range of measured temperatures. An accurate analysis of EPR spectra, performed using two fitting programs (NLLS and EPRSIM), allowed us to obtain the thermodynamic profile to these major probe accommodations. Focusing the analysis on two-component EPR spectra, it was studied the influences of cholesterol and a membrane permeation enhancer on the mobility and distribution of spin label on these two main bilayer environments. Parte II Cutaneous leishmaniasis is a neglected tropical disease that infects millions of people worldwide, representing a serious public health problem. The current treatment is based on chemotherapy, using pentavalent antimonials compounds, which cause serious side effects. Electron paramagnetic resonance (EPR) spectroscopy of the spin-label analog of stearic acid (5-DSA ) was used to monitor the effect of the terpenes α-terpineol, 1,8-cineole, III (+)-limonene and nerolidol on the plasma membrane fluidity of Leishmania amazonensis promastigotes. Cytotoxic effects on the parasite were also measured to investigate the relationship between the cytotoxic potential of terpenes and their ability to alter membrane fluidity. All terpenes increased the fluidity of the cellular membrane, without significant differences at higher concentrations. However, the minimum concentration required to cause a change in the membrane was very different between the terpenes and similar to that caused 50% growth inhibition (IC50) showing a correlation between membrane alterations and cytotoxicity. The IC50 values of terpenes analyzed showed the following relationship: nerolidol < (+)-limonene < α-terpineol < 1,8-cineole, with an IC50 of 8 μM for nerolidol and 4700 μM to 1,8- cineole. The EPR spectra of the maleimide derivative spin label (6-MSL) covalently attached to the Leishmania membrane proteins indicated that the terpenes essentially do not alter the dynamics of protein backbone and only increase the mobility of the nitroxide side chain. Cell lysis was not detected at cytotoxic concentrations, as measured by the presence of spin-labeled membrane fragments. Since the terpenes are considered potent skin permeation enhancers with low irritation potential, this work suggests checking the possibility of terpenes applications in the treatment of tegumentary leishmaniasis, where terpenes could perhaps perform a dual action of be an active principle and at the same time facilitate the penetration of other molecules with antileishmanial activity.
Parte I A espectroscopia de Ressonˆancia Paramagn´etica Eletrˆonica (RPE) de marcadores de spin foi usada para estudar as principais acomoda¸c˜oes estruturais de sondas sens´ıveis ao ambiente nas bicamadas de fosfatidilcolinas com cadeias acilas saturadas e de comprimentos variando de 16 a 22 ´atomos de carbono. A an´alise mais detalhada foi feita sobre o marcador de spin 5-metil doxil estearato (5-DMS), cujos espectros de RPE permitiram identificar dois tipos distintos de componentes espectrais em equil´ıbrio termodinˆamico para temperaturas abaixo e acima da principal transi¸c˜ao de fase. A espectroscopia de RPE distingue duas componentes associando menor movimento com maior polaridade (denotado como componente 1) e maior movimento, com menor polaridade (componente 2), as quais podem ser atribu´ıdas a duas popula¸c˜oes de marcadores, sendo uma pr´oxima (estrutura mais r´ıgida) e outra longe da regi˜ao polar da membrana, respectivamente. Em temperaturas de at´e 22◦C apenas uma componente pode ser observada nos espectros enquanto que a 30◦C a componente 1 coexiste com uma fra¸c˜ao significativa da componente 2. Na fase l´ıquido-cristalina o 5-DMS mostrou duas componentes espectrais para todos os lip´ıdios estudados e em todo o intervalo de temperatura medido. Uma an´alise acurada dos espectros de RPE, realizadas utilizando dois programas de ajuste (NLLS e EPRSIM), permitiu-nos obter o perfil termodinˆamico para estas principais acomoda¸c˜oes do marcador. Focalizando nossa an´alise sobre espectros de RPE de duas componentes e usando o mesmo modelo de simula¸c˜ao dos espectros, foi estudada a influˆencia do colesterol e um modificador de permea¸c˜ao de mol´eculas atrav´es da pele, examinando principalmente a mobilidade e a distribui¸c˜ao do marcador de spin nesses dois principais ambientes da bicamada. Parte II A leishmaniose cutˆanea ´e uma doen¸ca tropical negligenciada que infecta milh˜oes de pessoas em todo mundo, representando um grave problema de sa´ude p´ublica. O tra- I tamento atual, baseado em quimioterapia, utiliza compostos pentavalentes antimoniais que causam s´erios efeitos colaterais. A espectroscopia de Ressonˆancia Paramagn´etica Eletrˆonica (RPE) do marcador de spin an´alogo do ´acido este´arico (5-DSA) foi utilizada para monitorar o efeito dos terpenos α-terpineol, 1,8-cineol, (+)-limoneno e nerolidol sobre a fluidez da membrana plasm´atica de promastigotas de Leishmania amazonensis. Os efeitos citot´oxicos sobre os parasitas tamb´em foram medidos para investigar as rela¸c˜oes entre os potenciais citot ´oxicos dos terpenos e suas capacidades de alterar a fluidez da membrana. Todos os terpenos aumentaram a fluidez da membrana celular, sem diferen¸cas significativas para concentra¸c˜oes mais elevadas. Entretanto, a concentra¸c˜ao m´ınima necess´aria para causar a altera¸c˜ao na membrana foi muito diferente entre os terpenos e semelhante daquela que causou 50% de inibi¸c˜ao do crescimento (IC50), denotando uma correla¸c˜ao entre altera¸c˜oes na membrana e citotoxicidade. Os valores de IC50 dos terpenos analisados seguiram a rela¸c˜ao nerolidol < (+)-limoneno < α-terpineol < 1,8-cineol, com um IC50 de 8 μM para o nerolidol e 4700 μM para o 1,8-cineol. Os espectros de RPE do marcador de spin derivado do maleimido (6-MSL) covalentemente ligado `as prote´ınas de membrana da Leishmania indicaram que os terpenos essencialmente n˜ao alteram a dinˆamica do esqueleto prot´eico e apenas aumentam a mobilidade da cadeia lateral do nitr´oxido. A lise celular n˜ao foi detectada nas concentra¸c˜oes de citotoxicidade, quando medida pela presen¸ca de fragmentos de membranas marcadas. Como os terpenos s˜ao considerados potentes facilitadores da permea¸c˜ao atrav´es da pele com baixo potencial de irrita¸c˜ao, este trabalho sugere a realiza¸c˜ao de testes para verificar a possibilidade de aplica¸c˜oes no tratamento da Leishmaniose tegumentar, onde os terpenos talvez pudessem desempenhar uma a¸c˜ao dupla, de ser um principio ativo e ao mesmo tempo facilitar a penetra¸c˜ao de outras mol´eculas com atividade leishmanicida.

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50

Souza, Amanda de. "Variabilidade dos óleos voláteis de espécies de Myrtaceae nativas da Mata Atlântica". Universidade de São Paulo, 2009. http://www.teses.usp.br/teses/disponiveis/41/41132/tde-25052009-153706/.

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A conservação das áreas remanescentes de Mata Atlântica envolve o desenvolvimento de programas de uso sustentável que requerem um amplo conhecimento da fauna e da flora. Myrtaceae é uma família de grande importância no bioma, sendo dominante em muitos fragmentos, e destaca-se pela produção de óleos voláteis, substâncias com grande potencial de utilização pelas indústrias alimentícia, cosmética e farmacêutica. Considerando-se que a variabilidade de óleos essenciais é pouco conhecida para espécies brasileiras de Myrtaceae, este trabalho teve por objetivo avaliar as alterações destes metabólitos nas folhas algumas destas espécies, em função de aspectos diuturnos, sazonais e de localização geográfica, bem como investigar algumas atividades biológicas. Os óleos foram obtidos por hidrodestlilação e analisados por CG-EM. Os resultados demonstraram uma predominância de compostos sesquiterpênicos para sete das nove espécies estudadas, especialmente espatulenol, β-cariofileno, α-cadinol e ς-elemeno. Entretanto, não foram verificados padrões de variabilidade diuturna ou de sazonalidade para os óleos em nenhuma das espécies alvo, observando-se, porém, alterações na composição entre os diferentes anos de coleta para as espécies Campomanesia guaviroba (DC.) Kiaersk., Myrcia splendens (Sw.) DC., e Myrcia macrocarpa DC. Alterações na composição dos óleos de espécimes coletados em fragmentos distintos foram verificadas em Eugenia cuprea (O. Berg) Nied. e Calyptranthes lucida Mart. Ex DC., porém com inversão, entre as duas espécies, da rota biossintética de sesquiterpenos mais ativa em cada localidade, sugerindo que as variações não são decorrentes de diferenças ambientais. A análise das atividades biológicas demonstrou que os óleos voláteis investigados não apresentam potencial anticolinesterásico, mas possuem potencial para a utilização como antimicrobianos, destacando-se a atividade antifúngica dos óleos de C. guaviroba, M. splendens e M. macrocarpa frente a Cladosporium cladosporioides e C. sphaerospermum. Os resultados obtidos neste trabalho sugerem que os fatores endógenos são mais importantes para a variabilidade dos óleos voláteis nas espécies de Myrtaceae estudadas do que os aspectos ambientais. A ampla variabilidade individual verificada sugere grande diversidade genética para estas espécies, informação fundamental a ser considerada para a definição de estratégias de conservação da Mata Atlântica.
The conservation of the Atlantic Rain Forest remnants involves the development of sustainable use programs that require an extensive knowledge of its flora and fauna. Myrtaceae is an important family in this biome, being dominant in many fragments, and is also recognized by the production of volatile oils, substances with great potential for food, cosmetic and pharmaceutical industries. Considering that there is a lack of scientific information on essential oil variability for Brazilian Myrtaceae species, this work aimed to evaluate the changes of these metabolites in the leaves of some species, considering diurnal and seasonal aspects, and geographical location, as well as to investigate some biological activities. The oils were obtained by hydrodistlillation and analyzed by GC-MS. The results showed a predominance of sesquiterpenes compounds for seven of the nine species studied, especially espatulenol, β-caryophyllene, α-cadinol and ς-elemene. However, no diurnal or seasonal patterns of variability were observed for all target species, but changes in the composition among the analyzed years were found for Campomanesia guaviroba (DC.) Kiaersk., Myrcia splendens (Sw.) DC. and Myrcia macrocarpa DC. Differences in volatile oil composition for specimens collected in different locations were observed for Eugenia cuprea (O. Berg) Nied. and Calyptranthes lucida Mart. Ex DC., but with an inversion, between the two species, of the main sesquiterpene biosynthetic routes acting in each area, suggesting that the variations are not due to environmental differences. The analysis of the biological activities showed that the investigated volatile oils do not exhibit an important anticholinesterasic potential, but rather an antimicrobial one, particularly the antifungal activity of C. guaviroba, M. splendens and M. macrocarpa oils against Cladosporium cladosporioides and C. sphaerospermum. The obtained results suggested that endogenous factors are more important for the volatile oil variability in the studied Myrtaceae species than the environmental aspects. The wide individual variability observed suggests a high genetic diversity for these species, which is an important issue for the establishment of strategies for Atlantic Rain Forest conservation programs.

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