Made available in DSpace on 2017-07-21T14:13:07Z (GMT). No. of bitstreams: 1 Barbara Justus.pdf: 5067495 bytes, checksum: d064324000b906135c0fa596e41d5911 (MD5) Previous issue date: 2016-02-24 / Lavandula dentata L. presents as a small shrub, is native of the Mediterranean, with great pharmacological potential. The objective of this paper was study the morphoanatomy of the leaf, determine its chemical composition, antioxidant activity, antimicrobial activity and evaluate the cytotoxic potential of the volatile oil of L. dentata. Botanical material was collected in the Medicinal Garden of Pharmacy course at the State University of Ponta Grossa (Paraná). Diacytic stomata images obtained by optical microscopy and scanning electron microscopy, were evidenced only on the abaxial surface of the leaf blade, non-glandular branched trichomes, glandular capitate and peltate, dorsiventral mesophyll and concave-convex truncated midrib on the abaxial surface. The yield of volatile oil obtained by hydrodestilation of the aerial parts was 0.85%, and showed 1-8 cineole as main component identified by GC/MS. Volatile oil of L. dentata showed an antioxidant activity similar to rutin and gallic acid when analyzed by phosphomolibdenium method. However, by the free radical DPPH and ABTS method, it showed a slight potential antioxidant. The volatile oil showed antimicrobial activity against gram-positive, gram-negative bacteria strains and Candida albicans, by broth microdilution. This study, for the first time, shows the cytotoxic effect of the vapor phase of the volatile oil from L. dentata on lung tumor cell line Calu-3. The IC50 calculated for liquid phase of volatile oil was 388.84 μg.mL-1.The fraction of oil vapor in a concentration of 750 μg.mL-1 reduced the cell viability of Calu-3 significantly, based on three different techniques, the MTT reduction assays, SRB and DNA-PI. The results of morphological evaluations by Rosenfeld dyes, acridine orange/ethidium bromide and Hoescht, as well as the lactate dehydrogenase release assay gave an indication that the oil is cytotoxic to induce the cells death by necrosis, which was confirmed by the fact that the oil does not generate phosphatidylserine externalization. However, due to reports in literature, the expression of P-glycoprotein, which confers drug resistance in tumors and block apoptosis, in Calu-3 cells can not confirm the absence of this mechanism as well. The oil vapor promoted cell cycle arrest in G0/G1 when the DNA content was evaluated by flow cytometry. Considering these results, additional studies may be recommended, in order to use the volatile oil L. dentata as material for the pharmaceutical industry, with particular emphasis on the use of oil vapor in the lung cancer treatment therapy via inhalation. / Lavandula dentata L. é um pequeno arbusto nativo do Mediterrâneo. É conhecida popularmente como lavanda e alfazema e é utilizada na medicina popular como antidiabético, anti-hipertensivo e antiprotozoário. O objetivo do presente trabalho foi realizar o estudo da morfoanatomia foliar e caulinar, bem como determinar a composição química, avaliar a atividade antioxidante, o efeito antimicrobiano e o potencial citotóxico do óleo volátil de L. dentata. As partes vegetativas aéreas foram coletadas no Horto Medicinal do Curso de Farmácia da Universidade Estadual de Ponta Grossa (Paraná). A partir dos métodos usuais de microscopia óptica e de microscopia eletrônica de varredura, foram evidenciados estômatos diacíticos apenas na face abaxial do limbo foliar, tricomas tectores ramificados e glandulares capitados e peltados, mesofilo dorsiventral e nervura central côncava-convexa truncada na face abaxial. Além disso, um caule com formato quadrangular, sistema vascular típico e calotas esclerenquimáticas bem desenvolvidas nas quatro arestas.A partir das folhas e caules, por hidrodestilação, obteve-se um teor de 0,85% de óleo volátil. O principal componente do óleo volátil identificado por CG/MS foi o 1-8 cineol. Pelo método fosfomolibdênico, o óleo volátil de L. dentata revelou uma capacidade antioxidante semelhante à rutina e ao ácido gálico. Entretanto, pelo método do radical livre DPPH e do ABTS, foi observado um leve potencial antioxidante. O óleo volátil de L. dentata apresentou um efeito antimicrobiano frente às cepas de bactérias grampositivas, gram-negativas e de Candida albicans, por meio da microdiluição em caldo. Neste trabalho foi evidenciado o efeito citotóxico tanto da fase líquida quanto da fase vapor do óleo volátil de L. dentata sobre a linhagem tumoral pulmonar Calu-3. O IC50 calculado para fase líquida do óleo volátil de L. dentata foi de 388,84 μg.mL-1. A fração da fase vapor do óleo na concentração de 750 μg.mL-1 reduziu a viabilidade celular da linhagem Calu-3 significativamente, efeito que foi corroborado por três diferentes técnicas, redução do MTT, SRB e DNA-PI. Os resultados das avaliações morfológicas empregando os corantes de Rosenfeld, alaranjado de acridina/brometo de etídio e Hoescht, bem como pelo ensaio de liberação de lactato desidrogenase são sugestivos de que a citotoxicidade da fase de vapor óleo está relacionada a indução de morte celular por necrose, o que foi confirmado pelo fato do vapor do óleo não gerar externalização de fosfatidilserina. Todavia, devido a relatos na literatura de que as células Calu-3 expressam a proteína glicoproteína-P, a qual confere em tumores resistência a fármacos e bloqueio da apoptose, não se pode excluir a indução de morte celular por esse mecanismo também. O vapor do óleo de lavanda promoveu parada do ciclo celular em G0/G1 quando o conteúdo de DNA foi avaliado por citometria de fluxo. Considerando esses resultados, estudos adicionais podem ser recomendados, visando à utilização do óleo volátil de L. dentata como matéria prima pela indústria farmacêutica, com especial destaque para o emprego da fase vapor do óleo volátil na terapia de tratamento de câncer de pulmão por via inalatória.

Au sein des écosystèmes, les Composés Organiques Volatils (COVs) émis par les plantes jouent un rôle majeur dans les interactions trophiques. Ces signaux olfactifs vont renseigner les insectes phytophages sur la présence de leurs hôtes mais permettent aussi de recruter les ennemis naturels. Il a été montré que certains de ces composés pouvaient être utilisés pour manipuler le comportement des insectes phytophages s’attaquant aux cultures. La stratégie push-pull, vise à combiner des stimuli positifs et négatifs pour un insecte ravageur afin de le repousser d’une culture tout en l’attirant sur une plante piège implantée en périphérie du champ où il pourra être contrôlé. L’objectif de cette thèse est d’améliorer notre compréhension et nos connaissances sur la manipulation de la communication chimique entre les plantes et les insectes phytophages à l’aide de COVs de synthèse et de préférence d’hôte afin de mettre en place sur le terrain une stratégie de type push-pull pour protéger une culture de la mouche du chou (Delia radicum). Dans un premier chapitre, nous montrons que dans un système push-pull composé (i) de diffuseur de diméthyldisulfure DMDS (composante push) et (ii) d’une bordure de choux chinois supplémenté avec de l’acétate d’hexenyl (Z-3-HAC) (composante pull), il est possible de modifier fortement le comportement d’oviposition de D. radicum sans impacter de façon négative ses principaux ennemis naturels. Les limites agronomiques et d’utilisation du DMDS atteintes, nous avons recherché d’autres COVs ayant un effet répulsif. Lors d’une seconde expérimentation en push-pull, l’eucalyptol (1-8 cinéol) à permis de réduire le nombre de pupes de D. radicum retrouvées aux pieds des plants de brocoli de 60%. Suite à ce résultat encourageant, nous avons qualifié au laboratoire l’effet inhibiteur de ce monoterpène sur l’oviposition de la mouche du chou et en avons conclu qu’il permet de masquer le bouquet de COVs attractif d’un hôte. L’efficacité de la composante push étant fortement liée à la diffusion des COVs, nous avons ensuite testé au laboratoire et sur le terrain un nouveau type de diffuseur à base de cires végétales, permettant d’émettre l’eucalyptol de manière passive mais régulière pendant plusieurs semaines. L’étude réalisée montre le fort potentiel du diffuseur qui est à la fois bon marché, facile d’utilisation et fiable en terme de diffusion, permettant ainsi d’envisager son utilisation dans des stratégies de lutte intégrée à grande échelle. Parallèlement à l’étude de la composante push, nous avons cherché à améliorer l’efficacité de la composante pull. Le chou chinois (Brassica rapa) permet grâce à sa forte attractivité de capter et détourner la pression de phytophagie de la culture d’intérêt. Nous montrons qu’au sein de sa grande diversité, certaines variétés comme Richi (appartenant à la sous espèce pekinensis) sont préférentiellement attaqué par la mouche du chou, ce qui en fait de bons candidats au développement d’une composante pull efficace. A la lumière de la bibliographie et de nos résultats, nous proposons une réflexion générale sur le système étudié. Ainsi, nous concluons que, au moins dans le cas de la mouche du chou, les COVs ne peuvent probablement pas être les seuls outils considérés dans le développement d’une stratégie push-pull. / Within ecosystems, Volatile Organic Compounds (VOCs) emitted by plants play a major role in trophic interactions. These olfactive signals will inform phytophagous insects about the presence of their hosts, but they also allow to recruit their natural enemies. It has been shown that some of these compounds could be used to manipulate the behaviour of insect crop pests. The push-pull strategy aims at combining positive and negative stimuli to push a pest out of a crop and lure it into a trap crop located in the periphery of the field, where it can be controlled. The objective of this thesis is to improve our understanding and our knowledge on the manipulation of chemical communication between plants and phytophagous insects, using synthetic VOCs and host preference as tools, to protect a crop against the cabbage root fly (Delia radicum). In a first chapter, we show that in a push-pull made of (i) DMDS dispensers as a push component and (ii) chinese cabbage strips supplemented with hexényl acetate (Z-3-HAC) as a pull component, it is possible to strongly reduce oviposition behaviour in D. radicum without impacting its natural enemies. Agronomic limits to the use of DMDS led us to search for other repulsive VOCs. In a second push-pull field experiment, using eucalyptol (1-8 cinéol), reduced by 60% the number of D. radicum pupae produced in the crop. This encouraging result led us to characterize the inhibition effect of this monoterpene in the lab and concluded that it allows to mask the attractive blend of VOCs released by the host. The efficiency of the push component being strongly linked to that of the VOC diffusion, we have then tested both in the laboratory and in the field a new kind of dispenser made of vegetal waxes, allowing to diffuse eucalyptol passively but regularly during several weeks. This study shows the good potential of this device, which is affordable, easy to use and reliable in terms of diffusion, in integrated pest management strategies at a large scale. In parallel of our studies on the push component, we have also sought to increase the efficiency of the pull component. Thanks to its strong attractivity toward D. radicum, Chinese cabbage (Brassica rapa), allows to divert pest pressure from the cash crop. We show that within its important genetic diversity, some cultivars such as Richi (of the pekinensis subspecies) are preferentially attacked by D. radicum, which makes them good candidates to develop an efficient pull component. Using both the literature and our own results, we finally propose a general discussion on the system studied. We conclude that, at least in the case of the cabbage root fly, VOCs are probably not the sole tools to consider when trying to develop a push-pull strategy.