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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
361

The Effects of Lavender and Peppermint Essential Oils on Anxiety-Like Behaviors in Rodents

Beakas, Jenna Ashley January 2021 (has links)
No description available.
362

[pt] DESENVOLVIMENTO DE MÉTODOS ESPECTROFLUORIMÉTRICOS E CROMATOGRÁFICOS A LÍQUIDO PARA ANÁLISE DE ÓLEOS ESSENCIAIS CÍTRICOS. R / [en] DEVELOPMENT OF SPECTROFLUORIMETRIC AND LIQUID CHROMATOGRAPHIC METHODS FOR CITRUS ESSENTIAL OILS ANALYSIS

ROSANA CANDIDA MACEDO 05 September 2024 (has links)
[pt] O principal objetivo deste trabalho foi o desenvolvimento de métodosespectrofluorimétricos e de cromatografia líquida de alta eficiência em fase reversa(RP-HPLC, reversed-phase liquid chromatography) para análise de óleosessenciais cítricos (OEC). Para este fim, microemulsões livres de surfactante(SFMEs, surfactante-free microemulsions) foram utilizadas como uma abordagempara o tratamento das amostras.Primeiramente, a região de formação das SFMEs foi avaliada para diferentesproporções água:OE (1:4, 1:2, 1:1, 2:1, 4:1, m/m) na presença de propano-1-ol eoctan-1-ol (10:3 m/m). Titulações condutométricas indicaram agregados micelarescontendo OE (microemulsão do tipo óleo-em-água) para a proporção 4:1 (compartículas dispersas de raio hidrodinâmico de 95,7 ± 5,3 nm). Nessas condições, afluorescência aumentou, permitindo o uso da espectroscopia de fluorescência 3Dpara obtenção de padrões de impressão digital que foram utilizados para análisediscriminante de nove marcas brasileiras, juntamente com análise de componentes principais com desdobramento dos dados (UPCA, unfold principal components analysis). Uma variância cumulativa de 96,7 por cento foi obtida para os três primeiros componentes principais e os gráficos de pontuação mostraram uma localização distinta para cada grupo. Um estudo preliminar também mostrou a capacidade desses sistemas em avaliar condições de armazenamento e adulteração. O impacto das condições de armazenamento foi realizado ao longo de 21 dias expostos à luz, com resultados mostrando grandes diferenças espectrais em comparação com uma amostra armazenada em frasco âmbar a 22 graus C. A adulteração de OEs por fortificação com óleo de canola e óleo mineral foi detectada em diferentes níveis (1, 5, 10 e 20 por cento, m/m) e, além das diferenças espectrais, observou-se uma mudança na estabilidade da micro emulsão. Em uma segunda etapa do estudo, esses sistemas foram replicados para diferentes OEC, incluindo laranja doce e azeda, tangerina, limão e grape fruit. Estudos foram empregados para avaliar condições ótimas para a formação do sistema, visando abranger todos os OECs avaliados sem comprometer a reprodutibilidade da medição. A nova condição SFME adotada foi de 15 microL da fase oleosa contendo OE e octan-1-ol (1:2 v/v), 19 mL de água e propan-1-ol até o volume final de 25 mL. Além do baixo consumo de amostra, obteve-se um aumento significativo na fluorescência, apesar da menor proporção da fase oleosa. Os dados da matriz de excitação-emissão foram utilizados para análise de agrupamento. OUPCA foi aplicado com sucesso, com uma variância cumulativa de 99,5 por cento para os três primeiros componentes principais. A decomposição dos auto vetores revelou uma influência significativa dos comprimentos de onda de excitação/emissão de336/436 nm. Análises complementares por HPLC confirmaram a relação entre fluoróforos e a fração não volátil, característica dos OECs. A combinação de baixo consumo de amostra e alto teor de água torna a aplicação desses sistemas vantajosa para a diferenciação de OECs. A transparência e a baixa viscosidade também são consideradas aspectos positivos. Em uma terceira e última etapa, o efeito do meio de amostragem na análise de polimetoxiflavo nas (PMFs) no OE de laranja doce por RP-HPLC foi avaliado, utilizando o conhecimento adquirido nas etapas anteriores em relação à formação de sistemas SFMEs. Este estudo teve como foco a análise de PMFs presentes na fração não volátil do OE de laranja doce, que inclui tetra-O-metil-scutelareína, sinensetina, tangeretina, nobiletina e heptametoxiflavona. Dois métodos utilizando eluição isocrática com diferentes fases móveis, (A) água/metanol e (B)água/acetonitrila, foram empregados usando detecção absorciométrica e fluorimétrica. O meio de amostragem influenciou significativamente a eluição cromatográfica, afetando potencialmente a largura dos picos e o tempo de retenção, especialmente para tangeretina, onde um aumento de 300 e 103 por cento na intensidade de pico foi obtido para as fases móveis A e B, quando misturas com octan-1-ol foram utilizadas. Devido à coeluição entre nobiletina e tetra-O-metil scutelareína observada com a fase móvel A, o método foi validado utilizando a fase móvel B(acetonitrila/água, 50:50 por cento, v/v). A detecção de fluorescência forneceu valores delimites de detecção e quantificação mais baixos para sinensetina (1 e 3 microg mL-1) enobiletina (13 e 44 microg mL-1) do que os relatados na literatura. O método foi aplicado a amostras comerciais de OE de laranja doce, fornecendo resultados consistentes para todas as PMFs. / [en] The main goal of this work was the development of spectrofluorimetric and reversed-phase high-performance liquid chromatography (RP-HPLC) methods for citrus essential oils (CEO) analysis. For this purpose, surfactant-free microemulsions (SFMEs) were used as an approach for sample treatment. First, the SFME formation region was studied at different water:EO weight proportions (1:4, 1:2, 1:1, 2:1, 4:1 w/w) in the presence of propan-1-ol and octan-1-ol (10:3 w/w). Conductometric titrations indicated micellar aggregates containing EO (oil-in-water microemulsion) for the 4:1 proportion (droplets of hydrodynamic radius of 95.7 ± 5.3 nm). In such conditions, fluorescence increased allowing the use of 3D fluorescence spectroscopy to obtain spectroscopic fingerprint pattern that was used aiming discriminant analysis, considering nine EO Brazilian brands, along with unfold principal component analysis(UPCA). A cumulative variance of 96.7 percent was obtained for the first three principal components and score plots showed distinct location for each group. Preliminary study showed the capability of these systems in evaluating storage conditions, and adulteration. The impact of storage conditions was made over 21 days exposed to light with results showing large spectral differences compared to a sample stored in amber flask at 22 degrees C. Adulteration of EOs by canola and mineral oil fortification was detected at different levels (1, 5, 10 and 20 percent, w/w) and, in addition to the spectral differences, a change in microemulsion stability was observed. In a second stage of the study, these systems were replicated for different CEOs, including sweet and sour orange, tangerine, lemon, and grapefruit. Studies were employed to assess optimal conditions for system formation, aiming to encompass all evaluated CEOs without compromising measurement reproducibility. The new SFME condition adopted was 15 microL of the oily phase containing EO and octan-1-ol (1:2 v/v), 19 mL of water, and propan-1-ol up to the 25 mL final volume. In addition to low sample consumption, a significant increase in fluorescence was achieved, despite the lower proportion of the oily phase. Excitation-emission matrix data were utilized for clustering analysis. UPCA was successfully applied, with cumulative variance of 99.5 percent for the first three principal components. Eigenvectors decomposition revealed a significant influence of the 336/436 nm excitation/emission wavelengths. Complementary analyses by HPLC confirm the relationship between fluorophores and the non-volatile fraction, characteristic of CEOs. The combination of low sample consumption and high-water content makes the application of these systems advantageous for CEO differentiation. Transparency and low viscosity are also considered positive aspects. In a third and final stage, the effect of the sampling medium on the analysis of polymethoxyflavones (PMFs) in sweet orange EO by RP-HPLC was evaluated, utilizing the knowledge acquired in previous stages regarding the formation of SFME systems. This study was focused on analyzing PMFs present in the non-volatile fraction of sweet orange EO, which includes tetra-O-methyl-scutellarein, sinensetin, tangeretin, nobiletin, and heptamethoxyflavone. Two methods utilizing isocratic elution with different mobile phases, (A) water/methanol and (B) water/acetonitrile, were employed using absorciometric and fluorimetric detection. The sampling medium significantly influenced chromatographic elution, potentially affecting peak width and retention time, especially for tangeretin, where a 300 percent and 103 percent increase in peak intensity was obtained for mobile phases A and B, respectively, when mixtures with octan-1-ol were used. Due to co-elution between nobiletin and tetra-O-methyl scutelarein observed with mobile phase A, the method was validated using mobile phase B (acetonitrile and water 50:50 percent, v/v). Fluorescence detection provided lower LOD and LOQ values for sinensetin (1 and 3 microg mL -1 ) and nobiletin (13 and 44 microg mL -1 ) than reported in the literature. The method was applied to commercial sweet orange EOs samples, yielding consistent results for all PMFs.
363

Ekstrakcija bosiljka (Ocimum basilicum, Lamiaceae) ugljendioksidom u superkritičnom stanju i modelovanje ekstrakcionog sistema / Extraction of basil by supercritical carbon dioxide (Ocimum basilicum L.) and modeling of the extraction system

Filip Snežana 17 January 2014 (has links)
<p>U okviru ove doktorske disertacije, proučavana je ekstrakcija bosiljka (<em>Ocimum basilicum L.</em>) primenom postupka hidrodestilacije, Soxhlet ekstrakcije i ugljendioksidom u superkritičnom stanju. Određen je sadržaj etarskog ulja u drogi (0,565%), a primenom GC/MS(FID) metoda određen kvalitativni i kvantitativni sastav detektovanih komponenata. Identifikovane komponente svrstane su u nekoliko grupa (monoterpeni, seskviterpeni i njihovi oksidovani derivati). Rezultati ispitivanja pokazuju da je dominantno jedinjenje etarskog ulja bosiljka linalool (50,09%), i da ono pripada linaloolskom hemotipu (hemotip A).<br />Ispitan je uticaj temperature (40-60&deg;C) i pritiska (100&ndash;300 bar) superkritičnog ugljendioksida na promenu prinosa ekstrakta. Utvrđeno je da se kumulativni prinos ekstrakta povećava sa porastom pritiska ekstrakcije, dok u zavisnosti od temperature, prinos ekstrakcije zavisi od gustine rastvarača i napona pare komponenata u ekstraktu.<br />Primenom sukcesivne (frakcione) superkritične ekstrakcije izvr&scaron;eno je frakcionisanje, a dobijeni ekstrakti upoređivani u pogledu prinosa, kvalitativnog i kvantitativnog sastava.<br />Ispitivanja hemijskog sastava CO<sub>2</sub> ekstrakta (GC/MS i GC/FID) pokazala su da ekstrakti pored komponenata etarskog ulja sadrže i druga lipofilna jedinjenja (voskove, masna ulja, masne kiseline, fitosterole i sl.). Dominantne komponente u svim ispitivanim ekstraktima su linalool, eugenol i &delta;-kadinen, dok su &alpha;-bergamoten, germakren D, &gamma;-kadinen, &beta;-selinen i spatulenol komponente sa manjim saržajem.<br />Na osnovu eksperimentalnih rezultata kinetike superkritične ekstrakcije izvr&scaron;eno je modelovanje ekstrakcionog sistema bosiljak &ndash; superkritični CO<sub>2</sub>, primenom tri modela (Kandiah i Spiro, Brunner i Esquivel i sar.). Na osnovu srednjih vrednosti relativnog odstupanja modelovanih i eksperimentalnih vrednosti prinosa ekstrakcije, utvrđeno je da model Kandiah i Spiro pokazuje prihvatljivo slaganje, dok ostali modeli pokazuju lo&scaron;ije slaganje eksperimentalno određenih i modelom izračunatih prinosa ekstrakta.<br />U zavr&scaron;noj fazi rada ispitan je antioksidativni potencijal etarskog ulja i CO<sub>2</sub> ekstrakata, primenom DPPH metode. Najveću antioksidativnu aktivnost pokazao je ekstrakt dobijen na 100 bar, 60&deg;C (IC50 = 18,93 &mu;g/ml), koja je 5 puta veća od antioksidativne aktivnosti etarskog ulja bosiljka.</p> / <p>In this study, the extraction of basil (O. basilicum L.) ussing the hydrodistillation process, Soxhlet extraction and supercritical extraction with carbon dioxide were investigated. The content of essential oil was determined (0,565%), and the qualitative and quantitative composition of detected coumpound was made by GC/MS(FID). The identified coumpounds were classified into five groups (monoterpenes, sesquiterpenes and their oxidative derivates). The results of investigation shows that the dominant compound of basil essential oil is linalool (50,09%), and that it belongs to linalool chemotype (chemotype A).<br />The influence of temperature (40-60&deg;C) and pressure (100&ndash;300 bar) of supercritical carbon dioxide on extraction yields were studied. It was determined that the total yield of extract increases with the increaseing of extraction pressure, while the influence of temperature on the yield depends on the density of the solvent and vapor pressure of components in the extract.<br />Fractional supercritical fluid extraction was performed, and obtained extracts were compared regarding of yield, and the qualitative and quantitative composition of the extract. Chemical analyses of CO2 extract by GC/MS and GC/FID showed that extract contains, besides essential oil componentes, other lipophilic compounds (waxes, fatty oils, fatty acids, phytosterols, etc.). The few compounds were dominant in all analyzed basil extracts: linalool, and to a lesser extent eugenol, &delta;-cadinene, &alpha;-bergamotene, germacrene D, &gamma;-cadinene, &beta;-selinene and spathulenol. Based on the experimental results of the extraction kinetics, a modeling of basil &ndash; supercritical CO2 extraction system was performed, using three models (Kandiah and Spiro, Brunner, and Esquivel et al.). Based on the average values of the relative deviations of modeled and experimental values of extraction yield, it was found that the model Kandiah and Spiro shows acceptable agreement, while other models show lower agreement of the experimentally determined and model calculated extraction yield.<br />In finale phase of work the antioxidant potential of essential oil and CO2 extracts were examined, using DPPH method. The highest antioxidant activity showed CO2 extract obtained at 100 bar, 60&deg;C (IC50 = 18,93 &mu;g/ml), which is 5 time higher then antioxidant activity of basil essential oil.</p>
364

Influence des étapes de production du parfum issu des écorces d’orange amère (Citrus aurantium L. ssp amara) sur la qualité aromatique / Impact of the parfum production steps from bitter orange peelings (Citrus aurantium L. ssp amara) on the aroma quality

Deterre, Sophie 27 March 2012 (has links)
La liqueur Grand Marnier® produite par la Société des Produits Marnier-Lapostolle (SPML), contient un arôme d'orange amère. Cet arôme, appelé parfum, est obtenu à partir de l'huile essentielle (HE) d'écorces d'orange amère qui ont subi un procédé de macération-distillation. Le but de ce travail de thèse a été de cibler les composés d'arôme clés des écorces d'orange amère et de comprendre leur comportement au cours de la production du parfum, afin de trouver des stratégies d'optimisation. Les axes d'étude ont été les suivants : (1) identification des composés volatils odorants de l'HE et du parfum d'orange amère; (2) observation et compréhension des étapes de la production du parfum, des matières premières à la distillation, et étude de leur impact sur la qualité du parfum (3) étude détaillée de la distillation discontinue multi-étagée. Parmi les 51 et 37 composés volatils identifiés de l'HE et du parfum, nous avons détecté par olfactometrie 19 composés odorants dans l'HE et 7 dans le parfum. Avec les résultats de l'HE de l'axe (1), une sélection de composés d'arôme, dits marqueurs, a été faite selon certains critères. Cette procédure a été validée par une étude sensorielle de classification d'HE d'orange amère de différentes origines géographiques. Les observations et résultats de l'axe d'étude (2) ont montré que la distillation est l'étape de la production qui a le plus grand impact sur la qualité du parfum. Durant la distillation, 9 paramètres de conduite, tels que le titre alcoométrique volumique et le taux de reflux, ont été régulièrement enregistrés. En parallèle, les composés marqueurs ont été quantifiés dans des échantillons de distillat prélevés à des moments spécifiques de la distillation des têtes aux queues. La connaissance du comportement des composés marqueurs et de leurs propriétés physico-chimiques permet de mieux comprendre la conduite actuelle de la distillation. Ainsi des changements de paramètres de distillation ont été proposés et des essais pilote ont été mis en place dans l'axe d'étude (3). Dans l'optique de contrôler et d'optimiser la distillation discontinue multi-étagée, d'autres travaux ont été menés en simulation avec le logiciel BatchColumn de ProSim®. Cela nécessite de : 1) déterminer les données d'équilibre liquide-vapeur de certains composés marqueurs ; 2) trouver un modèle thermodynamique représentant les données expérimentales ; 3) intégrer les données expérimentales et le modèle choisi dans le logiciel BatchColumn. La distillation telle qu'elle est menée à la distillerie de la SPML a bien été représentée. De futures études, incluant des changements de paramètres tels que la composition de la charge du bouilleur, des paramètres de conduite et de structure pourront être réalisées, afin d'optimiser le procédé et voir l'impact de ces changements sur la qualité du parfum. / The Grand Marnier® liqueur produced by the Société des Produits Marnier-Lapostolle (SPML), is composed of a bitter orange aroma. This aroma, called parfum, is produced from essential oil (EO) of bitter orange peelings that underwent a maceration-distillation process. The aim of this PhD study was to focus on the key odour compounds of the bitter orange peelings, and understand their behaviours throughout the process, in order to find optimisation strategies. The following strategies were applied: (1) identification of odour volatiles compounds in bitter orange EO and parfum; (2) observation and understanding of the steps of the parfum production, from raw material to distillation, and study of their impacts on the quality of the parfum; (3) deep study of the multi-stage batch distillation. Among the 51 and 37 volatile compounds identified, we detected by olfactometry 19 odour compounds in EO and 7 in parfum. From the EO results of the strategy (1), a selection of odour compounds, called markers, was thus carried out applying specific filters. This procedure was validated by a classification sensorial study of bitter orange EO from different geographical origins. Observations and results of strategy (2) demonstrated that distillation has the biggest impact on the quality of the parfum. During distillation, 9 key process parameters, such as the alcoholic strength by volume and reflux rate, were continuously recorded. In parallel, markers compounds were quantified in distillate samples collected at specific control points from head to tail cuts. The behaviour of the key markers together the knowledge of their physical-chemical characteristics made it possible to better understand the current lead of the distillation. Thereby changes of distillation parameters were proposed and pilote trials were carried out in the strategy (3). In view to control and optimise the multi-stage batch distillation process, other works were focused on simulation with the BatchColumn software from ProSim®. This requires to: 1) determine the vapour-liquid equilibrium data of certain markers compounds; 2) build a thermodynamic model simulating real experimental data; 3) integrate the experimental data and the model selected in BatchColumn. With this approach, we easily represented the distillation as it was realised in the industry. Futures studies, including changes of parameters such as still composition, distillation and structure parameters, could be carried out to optimise the process and see the impact on these changes of the quality of the parfum.
365

Etude de synergie des effets chimiques et biologiques des lipides de réserve et des huiles essentielles des fruits et graines saisonniers de la sous-région Afrique Centrale / Study of synergy of chemical and biological effects of essential oils and reserve lipids of seasonal fruits and seeds from region Central Africa

Ngakegni-Limbili, Adolphe Christian 28 June 2012 (has links)
La composition en huiles essentielles et en lipides de réserve des graines et fruits saisonniers de quatre espèces végétales d’origine congolaise (Aframomum stipulatum (Gagnep) K. Schum, Aframomum giganteum (Oliv. and Hand) K. Schum, Spondias mombin L. et Nephelium lappaceum L.), a été déterminée par l’utilisation du couplage chromatographie en phase gazeuse/spectrométrie de masse. Les résultats obtenus ont permis de comprendre la bioaccumulation des huiles essentielles et des lipides de réserve dans les organes des différentes espèces. Dans le cas des espèces du genre Aframomum, les graines et les coques de fruits sont sources à la fois des huiles essentielles et des lipides de réserve. Les huiles essentielles des graines des deux espèces du genre Aframomun sont riches en composés monoterpéniques hydrocarbonés et oxygénés (β-pinène, 1,8-cinéole, phellandrène) avec des taux non négligeables de sesquiterpènes (α-sélinène et β-caryophyllène). Les huiles essentielles des coques des deux mêmes espèces se révèlent plus riches en monoterpénes oxygénés que celles des graines avec des composés très caractéristiques (β-pinène, 1,8-cineole, linalool pour A. giganteum et β-pinène, terpinéol, 1,8-cinéole pour A. stipulatum). On note dans les deux espèces, en dépit des procédés unitaires différents utilisés, la présence de lipides de réserve avec un profil acides gras du type palmitique-linoléique. Seuls les lipides de réserve ont été caractérisés dans Spondias mombin L. et Nephelium lappaceum L.. Les différentes parties du fruit de Spondias mombin sont dominées, comme dans le cas des Aframomum, par la présence des acides palmitique-linoléique avec une présence marquée de l’hentriacontane dans l’huile de peaux de fruits. L’huile d’amande de Nephelium lappaceum se distingue par sa richesse en acide arachidique C20:0 et acide 11- eicosénoïque C20:1. Les quatre espèces présentent un apport en phytostérols et en tocophérols. Des essais prometteurs de formulation de phytoproduits ont été réalisés avec des mélanges de tensioactifs, des a-monoglycérides et des huiles essentielles de graines de A. giganteum. Les activités antimicrobienne, anticancéreuse, antipaludique et anti-radicalaire ont été évaluées sur les extraits d’huiles essentielles et sur les lipides de réserve ainsi que sur les analogues synthétiques de lipides pris seuls ou en combinaison. Les résultats obtenus sont prometteurs / The composition of essential oils and fat of seasonal fruits and seeds of four plant species from the Congo (Aframomum stipulatum (Gagnep) K. Schum, Aframomum giganteum (Oliv. and Hand) K. Schum, Spondias mombin L. and Nephelium lappaceum L.), was determined by the combined use of mass spectrometry and gas chromatography. The results were used for understanding the bio-accumulation of essential oils and the storage of lipids in the organs of different species. In the case of the genus Aframomum, seeds and fruit shells are both sources of essential oils and fat. Seeds essential oils of the two species of Aframomun were rich in hydrocarbon and oxygenated monoterpene compounds such as β-pinene, 1,8-cineole, phellandrene, with significant levels of sesquiterpenes (α-selinene and β-caryophyllene). The shells essential oils of the same two species appear to be more rich in oxygenated monoterpenes than seeds, with a large structural features (β-pinene, 1,8-cineole, linalool for A. giganteum and b-pinene, terpineol, 1.8 -cineole for A. stipulatum). It is notified in both species that despite the different unit processes used, the presence of lipid with a fatty acid profile of the type palmitic-linoleic. Only lipids have been characterized from Spondias mombin L. and Nephelium lappaceum L.. The different parts of the fruit of Spondias mombin are dominated, like Aframomum, by the presence of palmitic-linoleic with a large presence of hentriacontane in the oil fruit skins. The kernel oil Nephelium lappaceum is distinguished by its wealth of arachidic acid C20:0 and 11-eicosénoïc acid C20:1. The four species contained in phytosterols and tocopherols. Testing promising formulation of herbal products were made with mixtures of surfactants, α-monoglycerides and essential oils from seeds of A. giganteum. Antimicrobial, anticancer, antimalarial and anti-radical activities were evaluated on the essential oils on the lipid as well as on the synthetic analogs of lipid alone or in combination. The results are promising
366

Filmes à base de blenda gelatina-quitosana com agentes ativos nanoemulsificados: desenvolvimento, caracterização e aplicação na conservação de mortadela fatiada refrigerada / Gelatin-chitosan blend based films loaded with nanoemulsified active agents: development, characterization and application to conservation of refrigerated sliced mortadella sausage

Pérez Córdoba, Luis Jaime 26 July 2018 (has links)
Um problema importante na produção de filmes ativos utilizando agentes ativos lipofílicos é a dificuldade de dispersão desses agentes na solução formadora de filme (SFF). As nanoemulsões podem ser uma alternativa para dispersar esses compostos na matriz biopolimérica. Os objetivos gerais desta pesquisa foram: 1) Desenvolver nanoemulsões óleo-em-água (O/A), com três agentes ativos na fase óleo, sendo dois antimicrobianos - cinamaldeído e óleo essencial de alho - e um antioxidante - alfa-tocoferol, e caracterizar essas nanoemulsões, inclusive sua estabilidade; e 2) Desenvolver, caracterizar e aplicar filmes ativos à base de gelatina-quitosana (G-Q), ativados com nanoemulsões O/A preparadas nas condições ótimas de processo: N1: &alpha;-tocoferol/cinamaldeído; N2: &alpha;-tocoferol/óleo essencial de alho; N3: &alpha;-tocoferol/cinamaldeído e óleo essencial de alho; e N4: óleo de canola. As nanoemulsões O/A foram preparadas usando um microfluidizador e Tween 20 e Span 60 como emulsificantes, caracterizadas e incorporadas na SFF. Os filmes foram produzidos pela técnica de Casting incorporando 0 ou 5 g agente ativo nanoemulsificado/100 g biopolímero e usando glicerol como plastificante. Os filmes foram caracterizados em termos de propriedades físicas, mecânicas, de permeabilidade ao vapor de água e isotermas de sorção, ópticas, microestruturais, e atividades antimicrobiana e antioxidante. Além disso, um estudo de migração dos agentes ativos em simuladores de alimentos foi realizado. A mortadela fatiada foi embalada em bandejas de poliestireno usando filmes como separador de fatias. Posteriormente, foi avaliada a aceitação sensorial da mortadela e sua vida útil com base em análises físico-químicas e microbiológicas. Os resultados mostraram emulsões O/A com tamanho de gota nanométrico, distribuição monomodal, potencial &zeta; &gt;-30 mV, alta estabilidade física e eficiência de encapsulação e propriedades ativas. Por outro lado, os filmes ativos não apresentaram diferenças significativas (p&gt;0,05) quanto à espessura, umidade, permeabilidade ao vapor de água e propriedades térmicas. A solubilidade em água, ângulo de contato, transmissão de luz, rigidez e resistência à tração e o brilho dos filmes foram reduzidos (p&lt;0,05), enquanto a deformação na ruptura, opacidade, grau de inchamento, cor e rugosidade da superfície aumentaram consideravelmente (p&lt;0,05) em razão da incorporação das nanoemulsões. Os modelos matemáticos de BET, GAB, Peleg e Oswin descreveram o comportamento de absorção de vapor de água dos filmes. As análises de DSC, FTIR e de difração de raios-X sugeriram compatibilidade entre a gelatina e a quitosana. Uma boa distribuição das nanogotas de óleo que encapsulavam os agentes ativos na matriz biopolimérica foi confirmada pelas análises de MEV e MFA. As nanoemulsões e os filmes ativos foram efetivos contra a Pseudomonas aeruginosa e Listeria monocytogenes e apresentaram atividade antioxidante frente aos radicais DPPH&bull;, ABTS&bull;+ e o reagente FRAP. As cinéticas de migração dos agentes ativos apresentaram comportamento Fickiano, com valores de coeficientes de difusão efetiva (D) entre 10-14 e 10-15 m2/s. Por outro lado, as fatias de mortadela embaladas sem filme foram as mais aceitas sensorialmente. Porém, o filme ativo utilizado ofereceu a maior ação antimicrobiana contra a L. monocytogenes e P. aeruginosa, inicialmente inoculadas na mortadela, além do maior efeito protetor contra bactérias deteriorantes, assim como inibiu a oxidação lipídica por mais tempo (5 dias) durante o estudo de vida útil. Em geral, este estudo evidenciou que os filmes à base de G-Q carregados com agentes ativos nanoemulsificados pode ter potencial como material de embalagem para melhorar a vida útil de alimentos. / A major problem in the production of active films using lipophilic active agents is their poor dispersion in the film-forming solution (FFS). Nanoemulsions may be an alternative to disperse these compounds within the biopolymeric matrix. The main aims of this research were: 1) to develop oil-in-water (O/W) nanoemulsions incorporated with three active agents in the oil phase, two antimicrobials - cinnamaldehyde and garlic essential oil - and one antioxidant - &alpha;-tocopherol and characterize those nanoemulsions, even their stability, and 2) Develop, characterize and applicate gelatin-chitosan (G-Ch) based films activated with O/W nanoemulsions prepared under optimal conditions: N1: &alpha;-tocopherol/cinnamaldehyde; N2: &alpha;-tocopherol/garlic essential oil; N3: &alpha;-tocopherol/cinnamaldehyde and garlic essential oil; and N4: canola oil. The O/W nanoemulsions were prepared using a microfluidizer and Tween 20 and Span 60 as emulsifiers, characterized, and then loaded into the FFS. The films were produced by the casting method incorporating 0 or 5 g of nanoemulsified active agent/100 g biopolymer, using glycerol as a plasticizer, and subsequently characterized in terms of their physical, mechanical, water vapor permeability, water sorption, optical, microstructural, antimicrobial and antioxidant properties. In addition, a study of active agent migration into food simulants was performed. The sliced mortadella was packed in polystyrene trays using films as a slice separator. After, a sensorial acceptance evaluation and shelf life study, based on physicochemical and microbiological analyses, were performed for the mortadella sausage. The results showed O/A emulsions with nanometric droplet size, monomodal distribution, &zeta; potential greater than -30 mV, high physical stability, high encapsulation efficiency, and active properties. On the other hand, the active films presented no significant differences (p&gt;0.05) in terms of thickness, moisture content, water vapor permeability, and thermal properties. The solubility in water, contact angle, light transmission, tensile strength, and brightness of films were reduced (p&lt;0.05), whilst the deformation at break, opacity, degree of swelling, color, and surface roughness considerably increased (p&lt;0.05), due to the incorporation of nanoemulsions. The mathematical models of BET, GAB, Peleg and Oswin described the water vapor absorption behavior of the films. The DSC, FTIR, and x-ray analyses suggested compatibility between the gelatin and chitosan. A good distribution of the oil nanodroplets encapsulating the active agents within the matrix was confirmed by AFM and SEM analyses. The active nanoemulsions and films were effective against Pseudomonas aeruginosa and Listeria monocytogenes, and showed antioxidant activity against the DPPH&bull; and ABTS&bull;+ free radicals, as well as the FRAP reagent. The kinetic migration of the active agents presented a Fickian behavior with values of effective diffusion coefficients (D) between 10-14 and 10-15 m2/s. On the other hand, the mortadella slices packed without films were the most sensorially accepted. However, the active films used offered the greatest effectiveness against L. monocytogenes and P. aeruginosa initially inoculated in the mortadella sausage, and highest protective effect against spoilage bacteria, as well as inhibiting lipid oxidation for longer time (5 days) during the shelf life study. Overall, this study offered clear evidence that G-Ch based films, loaded with nanoemulsified active agents, can have potential as packaging material for enhancing the shelf life of food.
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Production et analyse d'huiles essentielles de plantes aromatiques et médicinales de Madagascar. Caractérisation par RMN13C, CPG(Ir) et CPG-SM / Production and analysis of essential oils from aromatic and medicinal plants of madagascar.Caracterisation by RMN13C, CPG(Ir) et CPG-SM

Rabehaja Rakotondragaby, Delphin Justin 28 May 2013 (has links)
Ce travail a été effectué dans le cadre d’une convention de cotutelle entre les Universités de Corse et d’Antananarivo. Il a contribué à la caractérisation de cinq Plantes de Madagascar à travers la composition chimique de leurs huiles essentielles (HE). Quatre plantes aromatiques et médicinales (Cymbopogon giganteus var. madagascariensis, Tana bojeriana, Croton kimosorum et Croton sp.) poussent à l’état spontané dans la région sub-aride du sud-ouest de Madagascar (Toliara) alors que l’espèce Vepris madagascarica est présente dans la forêt dense humide du nord-est (Vohémar). Ainsi, nous avons étudié par combinaison CPG (IR), CPG-SM et RMN 13C la composition chimique d’huiles essentielles obtenues par hydrodistillation (appareil type Clevenger) et par entraînement à la vapeur d’eau (Alambic).Les huiles essentielles de Cymbopogon giganteus Chiov. var. madagascariensis (A. Camus) ou Ahibero possèdent une composition chimique comparable avec celles des espèces Cymbopogon giganteus Chiov. africaines décrites dans la littérature. Elles sont dominées par les quatre menthadiénols (cis- et trans-p-mentha-1(7),8-dièn-2-ol, cis- et trans-p-mentha-2,8-dièn-1-ol) et le limonène. Nous avons aussi identifié quatre hydropéroxydes possédant le squelette p-menthane. Une monographie de l’huile essentielle d’Ahibero a été proposée à l’intention des utilisateurs de cette huile essentielle.La composition chimique de l’HE de Tana bojeriana Baker est caractérisée par la présence majoritaire de l’-phellandrène (30,4%), de la carvone (22,3%), du limonène (13,3%) et du dill éther (7,7%). Cette composition chimique apparait très proche de celle d’Anethum graveolens (Apiaceae). La présence du trans-p-menth-2-èn-1,6-diol et du p-mentha-1(7),2-dièn-6-ol lui confère une certaine originalité Elle pourrait donc constituer une alternative aux huiles essentielles qui sont bien implantées sur le marché des Plantes Aromatiques et Médicinales (PAM).La composition chimique de l’HE de feuilles de Vepris madagascarica (Baill.) H. Perrier est caractérisée par une très forte teneur en (E)-anéthole (78,2%). L’étude comparative de la composition chimique des huiles essentielles de feuilles (fraîches et séchées) et d’écorces de tronc confirme la prédominance du (E)-anéthole (69,5 à 84,6%). Compte tenu de la répartition restreinte de cette plante aromatique et en vue d’une gestion durable de cette espèce, son exploitation devrait être limitée aux huiles essentielles des feuilles qui pourraient ainsi constituer une source de (E)-anéthole, composé très utilisé en agro-alimentaire.Deux espèces de Croton endémiques de Madagascar ont été étudiées, Croton kimosorum Leandri (Zanapoly ou Napoly) et Croton sp. (Andriambolamena ou Riamena). Les huiles essentielles de ces deux plantes aromatiques et médicinales sont caractérisées par la présence du linalol (Zanapoly) et du limonène(Andriambolamena). La première HE est caractérisée par une majorité de composés oxygénés tandis que la seconde est dominée par les composés oléfiniques monoterpéniques. Dans les deux cas, de nombreux sesquiterpènes oxygénés ont été identifiés. Parmi eux, l’épi--bisabolol, jamais décrit dans une HE du genre Croton, est trouvé pour la première fois dans les deux espèces. / This study was conducted under an agreement of co-supervision between the Universities of Antananarivo (Madagascar) and Corsica (France). It contributed to the characterization of five malagasy plants through the chemical composition of their essential oils (EO). Four aromatic and medicinal plants: Cymbopogon giganteus var. madagascariensis, Tana bojeriana, Croton kimosorum and Croton sp. grow wild in the south-western region of Madagascar (Toliara) whereas the species Vepris madagascarica is widespread in the rainforest of the north-eastern region (Vohémar). The identification of components of EOs produced by hydrodistillation (Clevenger type apparatus) and by steam distillation (Alembic) has been obtained by combination of GC (RI), GC-MS and 13C NMR.Cymbopogon giganteus Chiov. var. madagascariensis (A. Camus) EO or Ahibero EO of Madagascar has similar chemical composition with Cymbopogon giganteus Chiov. african species described in literature. Its chemical composition is dominated by four p-menthadienols (cis- and trans-p-mentha-1(7),8-dien-2-ol, cis- and trans-p-mentha-2,8-dien-1-ol) and limonene. Moreover, four peroxides derivatives bearing the p-menthane skeleton were also identified. A monography has been proposed to Ahibero EO users.Tana bojeriana Baker EO is characterized by the predominance of -phellandrene (30.4%), carvone (22.3%), limonene (13.3%) and dill ether (7.7%). The chemical composition of this EO was very close to that of Anetum graveolens (Apiaceae family), constituents. The presence of trans-p-menth-2-en-1,6-diol and p-mentha-1(7) ,2-dien-6-ol, gives some originality to Tana bojeriana EO. It could be therefore an alternative for essential oils that are already well established on the Medicinal and Aromatic Plants market.The chemical composition of Vepris madagascarica (Baill.) H. Perrier leaf EO is characterized by a high content of (E)-anethole (78.2%). The comparative study of the chemical composition of leaves (fresh and dried) and bark trunk EOs confirmed the predominance of (E)-anethole (69.5 to 84.6%). Taking account of the restricted distribution of this aromatic plant and the need for sustainable management of this species, its potential use would be limited to leaf oil and could be a source for this compound widely used in food industry.Two species of Croton endemic from Madagascar were studied, Croton kimosorum Leandri (Zanapoly or Napoly) and Croton sp. (Andriambolamena or Riamena). Both aromatic and medicinal plants EOs are characterized by the presence of linalool (Zanapoly) and limonene (Andriambolamena). Croton kimosorum is characterized by a majority of oxygenated compounds, while the second is dominated by hydrocarbon monoterpenes. In both cases, several oxygenated sesquiterpenes are identified. Among these, the epi--bisabolol, never reported in of Croton EOs, was found for the first time in both species.
368

Adaptation d'un nez électronique pour le contrôle de la concentration et de l'humidité d'une atmosphère chargée en huile essentielle destinée à un effet thérapeutique médical / Adaptation of an electronic nose to control concentration and humidity of an essential oil charged atmosphere for medical therapeutic effect

Sambemana, Herizo 20 June 2012 (has links)
De nombreuses études récentes, basées sur des indicateurs physiologiques ou psychologiques, mettent en évidence les pouvoirs stimulants ou apaisants des odeurs sur des personnes souffrant de déficiences neurosensorielles. Or l'évaluation quantitative (rigoureuse, scientifique) des effets d'une stimulation olfactive à base d'huiles essentielles, nécessite de pouvoir contrôler de manière exacte et automatique la quantité de substances actives présentes dans l'air inhalé par le patient. Ce travail concerne la conception et la réalisation d'un système « diffuseur/détecteur » de gaz capable de générer des doses contrôlées d'huile essentielle dans l'atmosphère conditionnée d'une salle d'expérimentation. La diffusion est basée sur le contrôle de l'air bullant dans l'huile essentielle liquide (pin, lavande, orange douce), dont l'analyse physico-chimique et sensorielle nous a aidés à choisir leur domaine de concentrations. La détection des substances volatilisées est obtenue à l'aide d'un réseau de capteurs à oxydes métalliques commerciaux. L'analyse de signaux de réponse des capteurs aux différentes concentrations de l'huile de pin, après un filtrage numérique adéquat, a révélé une bonne sensibilité croisée des capteurs tant au niveau de la réponse temporelle qu'au niveau de sa courbe dérivée. Ainsi, nous avons pu extraire plusieurs paramètres représentatifs des réponses, habituellement utilisés dans la littérature, et surtout de nouveaux paramètres, caractéristiques de la phase dynamique, pour former la base d'apprentissage. L'analyse à l'aide de méthodes de classification (non supervisée puis supervisée) nous a permis de mettre en évidence la meilleure combinaison de paramètres pour une identification rapide et fiable de concentrations voisines. L'application aux deux autres huiles essentielle a été concluante, nous pouvons envisager de réaliser un prototype pour les essais de validation thérapeutique / Recent clinical studies have demonstrated the stimulating or relaxing effects of odorous stimulation on subjects suffering from neuro-sensoriel deficiencies. These studies concern generally the variation measurement of physiological parameters or psychological indicators in relation with odorous stimuli. To evaluate quantitatively the odorous effects of natural oil stimulations on the subject behavior or his cognitive performance, it is necessary to control automatically and accurately the quantity of the active substances present in the air inhaled by the patient. The aim of this work is to conceive a gas ?diffuser/detector? system to generate fixed concentration of an essential oil in an experimental chamber atmosphere. Diffusion unit is based on the control of the air flow arte bubbling through the liquid oil (pin, lavender, orange), and the range of the employed concentration range is determined after physic-chemical and sensorial analysis. The detection of volatilized substances is obtained using a matrix of commercial metal oxide gas sensors. The study of the sensor responses to different pin oil concentrations showed, after an adequate digital filtering, a good cross sensitivity of the sensors. So, we have extracted from each sensor response, several characteristic parameters, firstly classical ones, and then new ones representing the dynamic phase of the signal response, to create the learning data base. The analysis of these data using pattern recognition methods (non-supervised and then supervised) permitted us to highlight a set of parameters for a reliable and rapid identification of closed diffused oil concentrations. The application of the system with the two other oils was decisive: we can now carry out the realization of a prototype for the therapeutic tests
369

Estudo de formação e estabilidade de nanopartículas de poliácido lático para liberação controlada do óleo essencial de Shinus Molle L. / Study of the formation and stability of poly lactic acid nanoparticles for the controlled release of essential oil Shinus Molle L.

Silva, Geisiane Rosa da 03 July 2015 (has links)
A nanotecnologia é uma ciência interdisciplinar onde se desenvolve nanomateriais para uso em diversas áreas como a farmácia, cosmética e agroindústria. Um de seus objetivos é aprimorar propriedades de ativos para novas aplicações, por exemplo, através de sistemas para liberação controlada através do uso de biomaterias. Dentre estes biomateriais destaca-se o poliácido lático (PLA) que é constantemente aplicado como matriz polimérica de várias nanoestruturas para o encapsulamento de ativos. Na área cosmética, ativos como os óleos essenciais são de grande interesse. O óleo essencial de pimenta rosa (Schinus molle L.) é composto por terpenos que apresentam, entre outras, atividade antioxidante e inseticida. No presente trabalho desenvolvemos um novo sistema de nanopartículas de PLA em solução aquosa, para liberação controlada do óleo essencial Schinus molle L. visando a utilização cosmética. As nanopartículas de PLA foram avaliadas quanto a estabilidade através da técnica de espalhamento dinâmico de luz (DLS). A formação foi estudada através do uso de difração de raios X (XRD) e espectroscopia vibracional (FTIR). A morfologia foi observada por microscopia eletrônica de varredura (SEM) comparando-se alguns dos resultados obtidos por DLS. Os resultados obtidos mostraram que o sistema é estável por aproximadamente 100 dias quanto ao tamanho, polidispersão e carga de superfície, mesmo com a variação de pH da solução em relação ao tempo. A estabilidade do nanossistema foi atribuída ao tensoativo dodecil sulfato de sódio (SDS), além da própria semicristalinidade e alta massa molar do PLA. Os componentes do sistema apresentaram interações químicas comprovadas por FTIR. O estudo por SEM mostrou que as nanopartículas obtidas têm aparência esférica, com a matriz polimérica contínua e com vários tamanhos constituindo assim um sistema polidisperso, como observadas também por DLS. A eficiência de encapsulação de 83% avaliada por calorimetria exploratória diferencial (DSC) e a liberação do ativo analisada por gravimetria mostraram-se satisfatórias. O sistema de nanopartículas obtido é estável e, por tanto, com potencial adequado para aplicação em produtos cosméticos. / Nanotechnology is an interdisciplinary science through which nanomaterials are developed for use in areas, such as pharmaceutical, cosmetology and agribusiness. One of its objectives is the improvement in the properties of active compounds for new applications by, for example, systems that use biomaterials for controlled release. Lactic polyacid (PLA), one of such biomaterials, has been constantly applied as a polymer matrix of various nanostructures for the encapsulation of active compounds. In cosmetics, active compounds, as essential oils are of great interest. The essential oil of pimenta rosa (Schinus molle L.) is composed of terpenes, which display antioxidant and insecticide activities. This dissertation addresses the development of a new system of PLA nanoparticles in an aqueous solution for the controlled release of essential oil Shinus molle L. to be applied to cosmetology. The stability of PLA nanoparticles was evaluated by dynamic light scattering (DLS). The formation of the system was studied by X-ray diffraction (XRD) and vibrational spectroscopy (FTIR) and its morphology and polydispersivity were verified by scanning electron microscopy (SEM), comparing some of the results obtained by DLS. The results show that the system is stable for approximately 100 days regarding size, polydispersion and surface charge, even when the pH of the solution varies over time. Stability was assigned to surfactant sodium dodecyl sulfate (SDS), PLA\'s semi crystallinity and high molecular weight. The chemical interactions of the system\'s components were evidenced by FTIR. SEM revealed spherical nanoparticles with a continuous polymeric matrix and polydispersivity, also observed by DLS. Satisfactory results were provided by the 83% of encapsulation efficiency calculated by differential scanning calorimetry (DSC) and the drug release analyzed by gravimetric technique. The nanoparticle system obtained is stable and, therefore, suitable for application to cosmetics.
370

Toxicidade do óleo essencial de tagetes minuta L (Asteraceae) em larvas de aedes aegypti (Diptera: Culicidae) e protocolo de alimentação em camundongos swiss calb/C

Lima, Waldemir Pereira 18 February 2010 (has links)
Made available in DSpace on 2016-01-26T12:51:23Z (GMT). No. of bitstreams: 1 waldemirpereiralima_tese.pdf: 266828 bytes, checksum: 4d3bfe97aba0900f9364737e7267f696 (MD5) Previous issue date: 2010-02-18 / Tropical diseases have been a phenomenon of global concern, and among them the Dengue, because the mosquito that transmits the virus, Aedes aegypti (Diptera: Culicidae), became out of control, and new outbreaks have been discovered each day. Several means have been used in an attempt to control the insect life cycle. However, the indiscriminate use of many agents took the insect to develop some resistance to them. New perspectives are emerging as we find in nature means to control these mosquitoes. Is the case of essential oil of Tagetes minuta L. (Asteraceae) which, according to recent studies, plays an important role in the control of insects, including the Aedes aegypti. Objectives: develop a procedure for feeding female Aedes aegypti that does not cause stress in Swiss Balb/C mice, evaluate the toxicity and residual effect of essential oil of Tagetes minuta L (Asteraceae) on populations of Aedes aegypti. Methods: Swiss Balb/C mice were anesthetized arranged in the cage for feeding female mosquitoes for a period of one hour, three times a week. The essential oil was used in concentrations of 0,2 mL L-1; 0,225 mL L-1; 0,25 mL L-1; 0,275 mL L-1 and 0,3 mL L-1 starting from an initial dilution of 200mL L-1 in acetone, in one hundred third-stage larvae coming from Bauru-SP, São José do Rio Preto-SP, respectively, sensitive and resistant to temephos, and one hundred larvae of Rockefeller-USA. The tests were performed in four times, with three replicates for three consecutive days. Results: There was no pain or stress observed in mice during blood feeding by Ae aegypti. There was no difference between populations for susceptibility to Tagetes minuta L. and tests showed LC50 of 0,24; 0,25 and 0,21 mL L-1 and CL99, 9 at 0,35; 0,39 and 0,42 mL L- 1, respectively, for Rockefeller, Bauru and São José do Rio Preto. There was no residual effect of the oil. Conclusions: Sedation of Swiss Balb/C mice has provided it serve as a food source for female Aedes aegypti without pain or stress, and can be used by other researchers, since it was approved by the Ethics Committee of Animal Experiments (CEEA) of this institution. The LC50 of Tagetes minuta L. were equal, respectively, for larvae of the Rockefeller strain, Bauru, São José do Rio Preto, and the CL99, 9 were equal, respectively, for larvae of the Rockefeller strain, Bauru, São José do Rio Preto. The resistance of larvae to temephos had no effect on lethal action exerted by the essential oil of Tagetes minuta L. Tests for evaluation of a residual oil after a week of contact, had zero mortality. The essential oil of Tagetes minuta L can be used as an alternative larvicide against Aedes aegytpi, however new studies are needed in order to isolate the fraction of larvicidal oil and incorporate other ingredients to increase their stability so that the product can have the residual effect. / As doenças tropicais têm sido um fenômeno de preocupação mundial, e entre elas a dengue, uma vez que o mosquito transmissor dos vírus, Aedes aegypti (Diptera: Culicidae), tornou-se fora de controle, e novos focos têm sido descobertos a cada dia. Vários meios já foram utilizados na tentativa de controlar o ciclo de vida inseto. Entretanto, o uso indiscriminado de muitos agentes levou o inseto a desenvolver certa resistência aos mesmos. Novas perspectivas estão surgindo já que podemos encontrar na própria natureza meios de controlar esses Culicideos. É o caso do óleo essencial de Tagetes minuta L. (Asteraceae) que, de acordo com estudos recentes, desempenha importante papel no controle de insetos, inclusive do Aedes aegypti. Objetivos: Desenvolver um procedimento de alimentação de fêmeas de Aedes aegypti que não cause estresse em camundongo Swiss Balb/C; avaliar a toxicidade e o efeito residual do óleo essencial de Tagetes minuta L (Asteraceae) em populações de Aedes aegypti. Material e métodos: Camundongos Swiss Balb/C anestesiados e sedados foram dispostos em gaiola para alimentação de fêmeas do mosquito por um período de uma hora três vezes por semana. O óleo essencial, foi utilizado nas concentrações de 0,2mL L-1; 0,225mL L-1; 0,25mL L-1; 0,275mL L-1 e 0,3mL L-1 partindo-se de uma diluição inicial de 200mL L-1 em Acetona, em cem larvas de terceiro estágio procedentes de Bauru-SP e São José do Rio Preto-SP, respectivamente, sensíveis e resistentes ao temephos, e, cem larvas de Rockefeller-EUA. Os testes foram realizados em quadriplicata, com três repetições, por três dias consecutivos. Resultados: Não foi observado dor ou estresse dos camundongos durante hematofagia pelas fêmeas de Ae aegypti. Não houve diferença entre as populações quanto à susceptibilidade a Tagetes minuta e os ensaios demonstraram CL50 de 0,24, 0,25 e 0,21mL L-1 e CL99,9 em 0,35, 0,39 e 0,42mL L-1, respectivamente, para Rockfeller, Bauru e São José do Rio Preto. Não foi observado efeito residual do óleo. Conclusões: A anestesia do camundongo Swiss Balb/C propiciou que este servisse como fonte alimentar para fêmeas de Aedes aegypti sem sofrer dor ou estresse, podendo este ensaio ser utilizado por como modelo, uma vez que foi aprovado pelo Comitê de Ética em Experimentação Animal (CEEA). As CL50 de Tagetes minuta L. foram iguais, respectivamente, para larvas da cepa Rockefeller, Bauru e São José do Rio Preto, assim como as CL99,9 que foram iguais, respectivamente, para larvas de da cepa Rockefeller, Bauru e São José do Rio Preto. A resistência das larvas do Culicideo ao temephos, não interferiu na ação letal exercida pelo óleo essencial de Tagetes minuta L. Os testes para avaliação do período residual do óleo após uma semana de contato, apresentaram mortalidade zero. O óleo essencial de Tagetes minuta L pode ser utilizado como larvicida alternativo contra Aedes aegytpi, entretanto novos estudos devem ser desenvolvidos com o objetivo de isolar a fração larvicida do óleo e incorporar outros componentes visando aumentar sua estabilidade, de maneira que o produto tenha efeito residual.

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