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Oleorresina de Copaifera spp.: caracterização, verificação da atividade antimicrobiana in vitro e avaliação preliminar de uma formulação em vacas leiteiras com mastite / Oleoresin of Copaifera spp.:characterization, verification antimicrobial activity in vitro and preliminary evaluation a formulationFaria, Maria Juíva Marques de 07 May 2014 (has links)
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Previous issue date: 2014-05-07 / Bovine mastitis is an inflammatory/infectious process of the mammary gland, its etiology is complex and multivariate. The most common mastitis has bacterial origin. Because of the high cost to treat this disease, and the bacterial resistance to antibiotics, beyond the losses due to the milk discard or the presence of drug residues in milk, studies are necessary to find out alternative methods to circumvent these problematic. The medicinal plants with antimicrobial activity have been making room in veterinary medicine with the objective to reduce the impact and the use of drugs indiscriminately, as well as maintain the integrity of the animal and control the dissemination of resistant bacterial lineage. Therefore, the aim of this work was characterize the oleoresin Copaifera spp., verify the antimicrobial activity in vitro of oleoresin and essential oil of Copaifera spp. in combating against aerobic and facultative isolated bacteria from cows’ milk with subclinical grade III mastitis diagnostic and evaluate preliminarily, in vivo, phytotherapic formulation composed of Copaifera spp. The tests for characterization of the oleoresin, confirmed its authenticity and quality, considered appropriate for use. The analyzes performed by gas chromatography coupled to mass spectrometry (GC/MS) and electrospray ionization Fourier transformed íonic cyclotron resonance mass spectrometry (ESI FT-ICR MS) identified sesquiterpenes and diterpenes present in the essential oil and oleoresin of Copaifera spp., respectively. The technique of High Performance Liquid Chromatography (HPLC) for sesquiterpenes, especially for β-caryophyllene, can be used in quality control of essential oil and oleoresin of Copaifera spp., as well as in phytotherapic formulation using oleoresin of Copaifera spp. The oleoresin showed better antimicrobial activity than the essential oil of Copaifera spp. (ρ<0,0001) in combating the 55 isolated bacteria. The antibiogram test of the three phytotherapic formulations demonstrated that the oleoresin had antimicrobial activity against the isolated microorganisms. The preliminary evaluation, in vivo, of a phytotherapic formulation containing 20% oleoresin of copaiba was neither effective nor safe, because it intensified the inflammatory process, requiring further tests, such as cytotoxicity and irritability of the raw material plant and of the vehicle used.
Key words: Bovine Mastitis. Oleoresin. Essential Oil. Copaifera spp. Minimum Inhibitory Concentration. ESI FT-ICR MS. / Mastite bovina é um processo inflamatório/infeccioso da glândula mamária, de etiologia complexa e multivariada, sendo a de origem bacteriana a mais frequente. Devido aos elevados custos dos tratamentos dessa enfermidade, resistência bacteriana aos antibióticos, além dos prejuízos inerentes ao descarte do leite ou à presença de resíduos de medicamentos no mesmo, faz-se necessário estudos que busquem métodos alternativos para contornar essa problemática. As plantas medicinais com potencial antimicrobiano vêm ganhando espaço na medicina veterinária com o objetivo de reduzir o impacto e o uso de medicamentos de forma indiscriminada, bem como manter a integridade do animal e controlar a disseminação de linhagens bacterianas resistentes. Diante disso, o objetivo desse trabalho foi caracterizar a oleorresina de Copaifera spp., verificar atividade antimicrobiana in vitro da oleorresina e do óleo essencial de Copaifera spp. frente às bactérias aeróbias e facultativas isoladas de leite de vacas diagnosticadas com mastite subclínica grau III e avaliar preliminarmente, in vivo, formulação fitoterápica à base de Copaifera spp. Os testes de caracterização da oleorresina de Copaifera spp. demonstraram sua autenticidade e qualidade, a qual foi considerada adequada para o uso. As análises realizadas por cromatografia gasosa acoplada à espectrometria de massas (CG/EM) e por espectrometria de massas com ionização por electrospray de ressonância ciclotrônica de íons por transformada de Fourier (ESI FT-ICR MS) identificaram os sesquiterpenos e diterpenos presentes no óleo essencial e na oleorresina de Copaifera spp., respectivamente. A técnica Cromatografia Líquida de Alta Eficiência (CLAE) para sesquiterpenos, em especial para β-cariofileno, pode ser utilizada no controle de qualidade de oleorresina e óleo essencial de Copaifera spp., bem como em formulação fitoterápica utilizando oleorresina de Copaifera spp. como matéria-prima vegetal. A oleorresina apresentou melhor atividade antimicrobiana do que o óleo essencial de Copaifera spp. (ρ<0,0001) frente às 55 bactérias isoladas. O teste de antibiograma das três formulações fitoterápicas demonstrou que a oleorresina de copaíba reproduziu a sua atividade antimicrobiana frente aos micro-organismos isolados. A avaliação preliminar, in vivo, de uma formulação fitoterápica contendo 20% oleorresina de copaíba não foi eficaz e nem segura, pois intensificou o processo inflamatório, havendo necessidade de testes futuros, como de citotoxicidade e de irritabilidade dessa matéria-prima vegetal e do veículo utilizado.
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Desenvolvimento de metodologias eletroanalíticas para determinação de pesticidas em óleo essencial de laranja / Development of electroanalytical methodologies for pesticides determination in orange essential oilFernanda Ramos de Andrade 01 August 2014 (has links)
A citricultura, introduzida no Brasil na época da colonização e explorada comercialmente a partir dos anos 30 do século passado, é um setor de grande importância para o agronegócio brasileiro. Atualmente, o Brasil detém 50% da produção mundial de laranja e cerca de 85% de toda exportação mundial, representando uma captação de divisas de cerca de 2,5 bilhões de dólares por ano, devido principalmente à exportação do suco de laranja. Apesar do suco ser o principal produto de exportação da citricultura, vários subprodutos com valor comercial são obtidos durante seu processo de produção, tais como os óleos essenciais cítricos. Esses subprodutos localizam-se na casca da fruta e são obtidos durante o processo de extração do suco de laranja por prensagem a frio. Devido ao uso intensivo de pesticidas na citricultura e que muitas vezes se acumula na casca da fruta é comum à obtenção de óleos essenciais com resíduos de pesticidas, o que reduz seu preço de mercado internacional e limita sua inserção em mercados exigentes como o Europeu, Japonês e Americano, por exemplo. Este trabalho propõe o desenvolvimento de metodologias eletroanalíticas para a determinação de alguns pesticidas amplamente utilizados na citricultura brasileira e que têm sido encontrados nos óleos essenciais produzidos pelas indústrias de processamento. Inicialmente, foram realizados testes para avaliação da eletroatividade de três pesticidas (piridafention, cihexatina e bromopropilato) amplamente utilizados no Brasil, mas que são proibidos na maioria dos países importadores, sendo, portanto, de importância estratégica. Utilizando-se a técnica de voltametria cíclica verificou-se que o piridafention apresenta resposta sobre o eletrodo compósito de grafite-poliuretana (GPU), a cihexatina apresentou eletroatividade sobre o eletrodo de filme de bismuto e o bromopropilato não foi eletroativo nas superfícies eletródicas testadas. Varreduras realizadas com voltametria cíclica mostraram que o piridafention apresenta um pico de redução em -0,80 V (vs. EECS) sobre eletrodo compósito de GPU em meio ácido (tampão Britton-Robinson 0,1 mol L-1) com características de processo irreversível. Em seguida, desenvolveu-se uma metodologia eletroanalítica, utilizando a técnica de voltametria de onda quadrada (SWV), com a otimização do pH da solução (1,0) e demais parâmetros da SWV como a frequência (80 s-1), amplitude do pulso (50 mV) e incremento de varredura (ΔEi = 5 mV). Curvas analíticas foram obtidas no intervalo de 1,46 a 17,1 µmol L-1, apresentando boa linearidade, com coeficiente de determinação (r2) de 0,998. Os limites de detecção (LD) e de quantificação (LQ) obtidos foram de 0,27 µmol L-1 e 0,92 µmol L-1, respectivamente. A precisão da metodologia desenvolvida foi avaliada por meio da repetibilidade e a reprodutibilidade e a exatidão determinada pelo erro relativo. Os testes de recuperação realizados pelo método de adição de padrão forneceram valores de 98%. A metodologia eletroanalítica desenvolvida para determinação do piridafention foi aplicada em amostras de óleo essencial de laranja, contaminadas com três níveis de concentração 1,5, 2,9 e 5,9 µmol L-1. Foram avaliados quatro procedimentos de extração líquido-líquido, utilizando água Milli-Q como extrator: i) agitação manual da mistura (10 mL de óleo e 10 mL de água) por 4 minutos com repetição do procedimento por 3 vezes; ii) agitação magnética da mistura (5 mL de óleo e 50 mL de água) por 20 minutos em uma única etapa, à temperatura ambiente; iii) agitação magnética da mistura (5 mL de óleo e 50 mL de água) por 20 minutos em uma única etapa, à temperatura de 45°C; iv) agitação da mistura em mesa orbital com tempo de agitação variando de 5 até 180 minutos. Os melhores resultados foram obtidos com o procedimento utilizando a agitação por mesa orbital (iv), sendo recomendado, portanto, para extração do piridafention em amostras de óleo essencial de laranja. No caso da cihexatina, os testes realizados visando à determinação de uma metodologia eletroanalítica mostraram uma baixa reprodutibilidade do eletrodo filme de bismuto inviabilizando a sua aplicação na eletroanálise da cihexatina. Entretanto, devido à importância da cihexatina e do bromopropilato recomenda-se a realização de mais estudos eletroquímicos com o objetivo de se estabelecer novos métodos de análise. / The citrus production introduced in Brazil during the colonization period and commercially exploited since 1930, is very important for the Brazilian agribusiness. Currently, Brazil is responsible for 50% of the total world citrus production and for about 85% of the citrus world exportation trade, representing an income of about 2.5 billion dollars for the country yearly. The orange juice is the major product of the citrus industry, but other commercially valuable byproducts can be obtained during the manufacturing process, such as the citrus essential oils. These byproduct, located at the orange fruit exocarp, are extracted during the juice production process by cold pressing. Due to the use of pesticides in the citrus production, these agrochemicals can be occasionally presented in extracted essential oil products as unwished residues, which significantly reduce their values in the international market and restrict their insertion in exigent markets as the European, Japanese and North American, for instance. This study aim to develop electroanalytical methodologies for the determination of some pesticides widely employed in the Brazilian citrus production and that has been found in the essential oils produced by the processing industries. Preliminar tests were conducted to evaluate the electroactivity of three pesticides (pyridaphention, cyhexatin and bromopropylate) widely applied in Brazil, but not regulated for use in most of the importing countries. Using the cyclic voltammetry technique, these experiments showed that pyridaphenthion presented a good electrochemical response on the graphite-polyurethane composite electrode (GPU), cyhexatin showed electroactivity on thin bismuth film electrode and bromopropylate was not electroactive on the tested electodes. Studies conducted using cyclic voltammetry showed that pyridaphenthion presents a reduction peak in -0.8 V (vs. ESCE) on GPU in acidic medium (Britton - Robinson buffer 0.1 mol L- 1(BR)) with features of an irreversible process. The electroanalytical methodology for pyridaphenthion analysis was developed using square wave voltammetry (SWV) with optimization of pH (1.0) and the SWV scanning parameters, as pulse frequency (80 s-1), amplitude (50 mV), and increment (ΔEi = 5 mV). An analytical curve was obtained for concentrations ranging from 1.46 a 17.1 µmol L-1, showing good linearity expressed in the determination coefficient (r2) of 0.998. The detection limit (LOD) and quantification limit (LOQ) obtained were 0.27 µmol L-1 and 0.92 µmol L-1, respectively. The precision was evaluated by means its repeatability and reproductibility, while accuracy was assessed by means relative error. Recovery experiments conducted using the standard addition method provided a concentration recovering level of 98%. The electroanalytical methodology developed for pyridaphenthion was applied in citrus essential oil samples spiked with three concentration levels 1.5, 2.9 and 5.9 µmol L-1. Four liquid-liquid extraction procedures were evaluated using only Milli-Q purified water as extracting agent: i) manual stirring of the mixture (10 mL of essential oil and 10 mL of water) during 4 minutes, repeating the procedure three times; ii) magnetic stirring of the mixture (5 mL of essential oil and 50 mL of water) during 20 minutes, in a single step, at room temperature; iii) magnetic stirring of the mixture (5 mL of essential oil and 50 mL of water) during 20 minutes, in a single step, at 45o C; iv) orbital shaking of the mixture (5 mL of essential oil and 50 mL of water) for different period of times varying from 5 to 180 minutes. The best results were obtained with the procedure using the orbital shaking table (iv), which is, therefore, recommended for extraction of pyridaphention residues in citrus essential oils samples. For the cyhexatin, studies carried out aiming to determine an electroanalytical methodology, showed low reproducibility of the bismuth film, preventing its application in the electroanalysis of cyhexatin. However, due to the importance of these pesticides in citrus essential oils production it is recommended additional studies regarding the electrochemistry and electroanalysis of these chemicals.
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Estudo da extração do óleo de pitanga (Eugenia uniflora L.) vermelha e roxa empregando os solventes CO2 e n - propano em altas pressões / Study on red and purple Surinam cherry (Eugenia uniflora L.) oil extraction by utilizing CO2 and n propane solvents at high pressuresSilva, Simone Braga da 15 February 2012 (has links)
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Previous issue date: 2012-02-15 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / From Surinam cherry s leaves (Eugenia uniflora L.) it is possible to extract oil that has been utilized industrially, especially by cosmetics and pharmaceuticals sectors. The extraction of this oil by using conventional methods often causes the thermal degradation of its components, and an interesting alternative has been the use of supercritical extraction technology with organic solvents. In order to better evaluate the advantages of oil extracting from red and purple Surinam cherry s leaves in high pressure, the present paper aims to study this supercritical extraction by using the supercritical carbon dioxide and pressured n-propane as solvents. After drying and milling of red and purple Surinam cherry s leaves, they were underwent to oil extraction with CO2 supercritical fluids under different temperatures (50 and 60ºC) and the pressure (150 and 250 bar) and also n-propane in different temperature (30, 45 and 60ºC) and pressure conditions (40, 60 e 80 bar). The coupling of a fractionation column in supercritical fluid extraction was used to separate components of the extract. Three distinct stationeries phases were evaluated: silica, alumina and Amberlit®. The extracted oil underwent to a gas chromatography coupled to the mass spectrometry (CG-EM) for a quantitative analysis, showing the alpha-bisabolol as composed of greater interest in its industrial application. The extraction kinetics of both solvents were obtained in an experimentally way. The experimental data were adjusted appropriately to the mathematical Sovavá model. / Das folhas de pitanga (Eugenia uniflora L.) é possível extrair um óleo que tem sido bastante utilizado industrialmente, principalmente nos segmentos cosméticos e farmacêuticos. As extrações deste óleo utilizando os métodos convencionais geralmente causam a degradação térmica de seus componentes, e uma alternativa interessante tem sido a utilização da tecnologia de extração supercrítica com solventes orgânicos. Para avaliar melhor as vantagens da extração em pressões elevadas do óleo das folhas de pitanga de frutos vermelha e roxa, o presente trabalho teve como objetivo estudar este tipo de extração supercrítica utilizando como solventes o dióxido de carbono supercrítico e o n- propano pressurizado. Após secagem e moagem das folhas de pitanga vermelha e roxa, as mesmas foram submetidas à extração do óleo com os solventes CO2 supercrítico sob diferentes condições de temperatura (50 e 60°C) e de pressão (150 e 250 bar) e também n-propano em diferentes condições de temperatura (30, 45 e 60°C) e de pressão (40, 60 e 80 bar). O acoplamento de uma coluna de fracionamento na extração supercrítica foi usado para separar os componentes do extrato. Foram avaliadas 3 fases estacionárias distintas: sílica, alumina e Amberlit®. O óleo extraído foi submetido à cromatografia gasosa acoplado a espectrometria de massa (CG-EM) para análise qualitativa, apresentado o alfa-bisabolol como composto de maior interesse pela sua aplicação industrial. A cinética da extração de ambos os solventes foram obtidas de forma experimental. Os dados experimentais ajustaram-se adequadamente ao modelo matemático de Sovová.
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ESTUDO ANALÍTICO E AVALIAÇÃO DA ATIVIDADE LARVICIDA DA MISTURA DOS ÓLEOS ESSENCIAIS DAS FOLHAS DA Pimenta dioica Lindl E DOS GALHOS DE Aniba duckei Kostermans FRENTE AO MOQUISTO Aedes Aegypti (LINNAEUS, 1762) / ANALYTICAL STUDY AND EVALUATION OF MIXTURE OF LARVICIDAL ACTIVITY OF ESSENTIAL OILS FROM THE LEAVES OF Pimenta dioica Lindl AND THE STEMS OF Aniba duckei Kostermans FORWARD TO Aedes aegypti (LINNAEUS, 1762)Pereira, Aldemir da Guia Schalcher 15 September 2009 (has links)
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Previous issue date: 2009-09-15 / In the search for alternative chemical control against Aedes aegypti L., various studies are developed and encouraged in order to find new substances insecticidal plant and in this context essential oils have been shown to be very promising. Extracted from the essential oils of species Lindl Pimenta dioica (leaves) and Aniba duckei Kostermans (stems) by means of hydrodistillation using a Clevenger system and promoted its mixture of equal parts. In this study, the larvicidal effect of the mixture of essential oils extracted from leaves of Pimenta dioica species Lindl and branches of Aniba duckei Kostermans were evaluated against the mosquito Aedes aegypti (Linnaeus, 1792). The blend of essential oils obtained were carried out analysis of constant physical and chemical density (0.904 g mL-1), refractive index (ND 25 = 1.379), solubility in 70% ethanol (1:2), color (yellow) and appearance (clear). Its components were identified by Gas Chromatography Mass Spectrometry (GC-MS). We identified and quantified by the method of standard components, myrcene (2.36%), limonene (1.00%), linalool (63.04%), myrcenol (1.13%), alilfenol (1, 40%) and eugenol (31.07%). The blend of essential oils and patterns of eugenol and linalool were tested in five concentrations: 20, 50, 70, 90 and 100 μg mL-1. The LC50 of the mixture of essential oils and the limits of confidence at 95% probability were calculated by the methods of Reed-Muench and Pizzi, respectively. The larvicidal activity was observed based on the percentage of dead larvae, the action was assessed 24h after treatment. The blend of essential oils had larvicidal activity with LC50 of 113,95 (±2.11) μg mL-1 and the patterns of eugenol 90,86 (±0,03) μg mL-1 and linalool 305,42 (±0,03) μg mL-1. The results indicate that the mixture of essential oils evaluated, is composed of substances that together with the major components eugenol and linalool provided greater larvicidal effect against the mosquito Aedes aegypti L. / Na procura pelo controle químico alternativo contra Aedes aegypti L., diversas pesquisas são desenvolvidas e estimuladas no intuito de se descobrirem novas substâncias inseticidas de origem vegetal e neste contexto os óleos essenciais têm se mostrado bastantes promissores. Extraiu-se os óleos essenciais das espécies Pimenta dioica Lindl (folhas) e da Aniba duckei Kostermans (galhos), pelo método de hidrodestilação, utilizando um sistema Clevenger e promoveu-se sua mistura em partes iguais. Neste trabalho, o efeito larvicida da mistura dos óleos essenciais extraídos das folhas da espécie Pimenta dioica Lindl e dos galhos de Aniba duckei Kostermans foram avaliados frente ao mosquito Aedes aegypti (Linnaeus, 1792). Da mistura de óleos essenciais obtida foram realizadas análises das constantes físico-químicas de densidade (0,904 g mL-1), índice de refração (ND 25º = 1,379), solubilidade em etanol a 70% (1:2), cor (amarela) e aparência (límpido). Os seus componentes foram identificados por Cromatografia Gasosa acoplada a Espectrometria de Massa (CG-EM). Identificou-se e quantificou-se pelo método da normalização os componentes, mirceno (2,36%), limoneno (1,00%), linalol (63,04%), mircenol (1,13%), alilfenol (1,40%) e eugenol (31,07%). A mistura dos óleos essenciais e os padrões de eugenol e linalol foram testados em cinco concentrações: 50, 70, 100, 130 e 150 μg mL-1. A CL50 da mistura de óleos essenciais e os limites de confiança a 95% de probabilidade foram calculados pelos métodos de Reed-Muench e Pizzi, respectivamente. A atividade larvicida foi verificada baseada na percentagem de larvas mortas; a ação foi avaliada 24h após o tratamento. A mistura de óleos essenciais tiveram atividade larvicida, com CL50 de 113,95 (±2,11) μg mL-1 e os padrões de eugenol 90,86 (±0,03) μg mL-1 e linalol 305,42 (±0,03) μg mL-1. Os resultados indicam que a mistura dos óleos essenciais avaliada é composta por substâncias que juntamente com os componentes majoritários eugenol e linalol propiciaram maior efeito larvicida frente ao mosquito Aedes aegypti L.
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ESTUDO DA COMPOSIÇÃO E APLICAÇÃO DO ÓLEO ESSENCIAL DE Origanum vulgare L. COMO AGENTE ANTIMICROBIANO EM SURURU (Mytella falcata). / STUDY OF COMPOSITION AND APPLICATION OF ESSENTIAL OIL Origanum vulgare L. AS ANTIMICROBIAL AGENT IN MUSSELS (Mytella falcata)Liston, Mariane da Silva 29 November 2013 (has links)
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Previous issue date: 2013-11-29 / Essential oils (OEs) are natural plant extracts and many of them are active as antimicrobials. Origanum vulgare L. (oregano) essential oil (OEO) has a promising application field as a food preservative. Several in vitro and application studies has been carried to evaluate the activity of OEs as antimicrobials in foods, but are not found in the literature survey data application in mussels. In this study we evaluated the chemical composition and the antibacterial effect of OEO in fresh chilled mussels from Mytella falcata species. The chemical constituents of the studied OE were identified by gas chromatography-mass spectrometry and for activity we analyzed the count of Escherichia coli and aerobic mesophilic bacteria, total volatile bases and pH. The addition of OEO at 1.4% resulted in complete inhibition of E. coli inoculated, reduced growth aerobic plate count bacteria and inhibit the process of deterioration. The activity of the OEO is attributed mainly to its major component, carvacrol, which has recognized antibacterial activity. The results indicate that the OEO can be applied to support of the extension of shelf life and safety of fresh mussels. / Óleos essenciais (OEs) são extratos naturais de plantas, sendo muitos deles ativos como antimicrobianos. O óleo essencial de Origanum vulgare L. (orégano) (OEO) possui um promissor campo de aplicação como conservante de alimentos. Diversos estudos in vitro e de aplicação têm sido feitos para avaliar a atividade de OEs como antimicrobianos em alimentos, no entanto não são encontrados na literatura dados de pesquisas de aplicação em mariscos. Neste estudo avaliamos a composição química do OEO e seu efeito antibacteriano em mariscos in natura refrigerados da espécie Mytella falcata, conhecidos como sururu. Os constituintes químicos do OE estudado foram identificados por cromatografia gasosa acoplada à espectrometria de massas e para a atividade realizamos as análises de contagem de Escherichia coli e bactérias mesófilas totais, teor de bases voláteis totais e pH do sururu. A adição de OEO a 1,4% resultou na completa inibição da E. coli inoculada, diminuição do crescimento de bactérias mesófilas totais e tornou o processo de deterioração mais lento. A atividade do OEO é atribuída principalmente ao seu componente majoritário, o carvacrol, que possui atividade antibacteriana. Os resultados obtidos indicam que o OEO pode ser aplicado no auxilio da extensão do prazo de validade e segurança de sururus in natura.
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Biosynthèse des composés odorants chez différents Pelargonium utilisés pour la production d'huile essentielle / Biosynthesis of odorant compounds from different Pelargonium used for the essential oil productionBlerot, Bernard 18 January 2016 (has links)
Pelargonium sp., appelé aussi « géranium » à odeur de rose ou « Géranium rosat » est l’une des plantes aromatiques et médicinales les plus cultivées au niveau international, essentiellement pour son huile essentielle (HE), utilisée par les industries des cosmétiques et de la parfumerie. Cette essence est extraite des feuilles par distillation vapeur et donne une HE riche de plusieurs centaines de molécules volatiles. Cette complexité est le résultat d’un long processus évolutif et de sélections variétales. Parmi ces composés volatils, les monoterpènes comme le géraniol, le citronellol et l’isomenthone, ou les sesquiterpènes comme le 10- γ-épi-eudesmol et le 6,9-guaiadiène, jouent un rôle prépondérant dans le parfum du Pelargonium. Les proportions relatives de ces différents composés sont d’ailleurs utilisées comme marqueurs de la qualité de l’HE et déterminent la typicité du parfum des différents cultivars et origines (P. cv. ‘rosat Bourbon’, P. cv. ‘rosat Chine’, P. cv. ‘rosat Égypte’ et P. cv. ‘rosat Grasse’). Malgré de très nombreux travaux portant sur la chimie de cette HE, il n’existe aucune information sur les voies de biosynthèse de ces molécules et aucun gène intervenant dans ces voies n’a été isolé. Durant cette thèse, nous avons cloné et caractérisé fonctionnellement par expression et purification des protéines recombinantes chez Escherichia coli des gènes codant les enzymes clés de ces voies de biosynthèse, les terpène synthases. Nous avons ainsi pu caractériser quatre terpène synthases, dont une géraniol synthase mono-produit. Nous avons isolé deux autres monoterpène synthases multi-produits, produisant pour l’une majoritairement du myrcène mais aussi trois autres monoterpènes, et pour l’autre majoritairement du 1,8-cinéole ainsi que 10 autres monoterpènes minoritaires. Enfin, une sesquiterpène multi-produit, la 10-γ-épi-eudesmol synthase, a été caractérisée. Nous avons ensuite analysé l’expression de la géraniol synthase et de la 10-γ-épi-eudesmol synthase dans différentes accessions de Pelargonium par RT-qPCR et nous avons montré la relation entre la capacité de production des différents composés volatils et le niveau d’expression dans les feuilles de ces deux terpène synthases. L’efficacité de la transformation génétique du Pelargonium par Agrobacterium tumefaciens étant élevée, des expériences de transgénèse ont aussi été réalisées afin de compléter la caractérisation fonctionnelle des gènes isolés. Dans une deuxième partie, nous avons réalisé l’analyse des essences produites par 64 espèces et cultivars de Pelargonium d’odeurs très diverses (citron, menthe, rose, abricot, pin, épices…). A l’aide d’analyses statistiques (ACP, analyse discriminante…), nous avons mis en évidence des relations entre la biochimie de ces cultivars, leurs odeurs et leurs proximités génétiques et cela afin de nous donner des pistes sur des croisements potentiellement intéressants. Enfin, un dernier chapitre est consacré à l’amélioration de la production d’HE en Égypte. Grâce à ce programme commencé il y a trois ans, nous améliorons chaque année la qualité et le rendement en HE de plus de 10 Ha de plantation de Pelargonium en Égypte. Un travail d’optimisation de la distillation ainsi que des améliorations des pratiques culturales, nous ont permis de produire une HE de qualité avec un rendement de plus de 60 kg.Ha-1 d’HE. D’autres expériences présentées dans ce chapitre soulignent l’influence de l’environnement et notamment de la température sur le ratio entre le citronellol et le géraniol ainsi que sur la biosynthèse de l’isomenthone, du 10-γ-épi-eudesmol et du 6,9-guaiadiène / Pelargonium sp, also named rose scented « geranium » or « Geranium rosat » is one of the the most cultivated aromatic and medicinal plant worldwide, especially for its essential oil (EO), which is used by cosmetic and perfumery industries. This essence is extracted from leaves by steam distillation and gives an EO containing several hundreds of organic volatile compounds (VOC). This complexity is the result of a long evolutive process and varietal selections. Among these VOC, the monoterpenes like geraniol, citronellol and isomenthone and the sesquiterpenes like 10-γ-epieudesmol and 6,9-guaiadiene, play an important role for the Pelargonium fragrance. The relative proportions of these compounds are used as EO quality markers and determine the different cultivars origins (P. cv. ‘rosat Bourbon’, P. cv. ‘rosat Chine’, P. cv. ‘rosat Egypt’ and P. cv. ‘rosat Grasse’). Despite the important researches on the chemistry of these EO, there is no information on the biosynthesis pathways for these molecules and no genes involved in the pathways have been isolated. During this PhD thesis, we have functionally characterized by recombinant proteins expression and purification in Escherichia coli, four genes, three monoterpene and one sesquiterpene synthases, coding for key enzymes in terpene biosynthesis pathway. The first enzyme is a mono-product geraniol synthase. The second enzyme is a multi-product enzyme with a major peak of myrcene and 3 minor peaks of other monoterpenes. The third enzymes is also a multi-product protein, producing 1,8-cineol as major product and 10 others monoterpenes. The last one is a multi-products sesquiterpene synthase producing mainly the 10-γ-epi-eudesmol and other sesquiterpenes. We have also analyzed the level of expression of the geraniol and 10 γ-epi-eudesmol synthases in several Pelargonium accessions by RT-qPCR and we have demonstrated the relationship between the level of expression of these two terpene synthases and the quantity of the related terpenes produced in leaves. Pelargonium transformation efficiency by Agrobacterium tumefaciens was tested in order to complete the functional characterization of the genes. In a second part, we have analyzed the essence of 64 species and cutivars of Pelargonium having very different fragrances like lemon, mint, rose, apricot, pine, spices… With different statistical tools (PCA, discriminant analysis…), we have highlighted the links between the biochemistry of these species and cultivars, their odors and their phylogenetic relationships. This worked gave us some interesting ideas for some new crossings. Finally, the last chapter concerns the EO production improvements in Egypt. Thanks to these researches, started 3 years ago, we are improving year after year our EO yield and quality in our 10 Ha R&D plantation. An important work was done to optimize the distillation process and improve the agricultural practices which abled us to reach a yield of 60 kg of EO per hectare. Some other experiments show the effect of the environmental factors such as the temperature on the biosynthesis of several important molecules like citronellol and geraniol, 6,9-guaiadiene and 10-γ-epi-eudesmol
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Préparation à petite et grande échelle des liposomes encapsulant l’huile essentielle de clou de girofle libre et sous forme de complexe d’inclusion dans l’hydroxypropyl-β-cyclodextrine : caractérisation des nanostructures et évaluation de leur effet antioxydant / Preparation at small and lare scale of liposomes encapsulating clove essential oil in free and hydroxypropyl-β-cyclodextrin inclusion complex forms : characterization of nanostructures and evaluation of their antioxidant effectSebaaly, Carine 05 January 2016 (has links)
L'huile essentielle de clou de girofle (HECG) et son constituant majeur l'eugénol (Eug) sont reconnus pour leurs propriétés biologiques. Ces principes actifs naturels peuvent constituer des alternatifs aux agents antimicrobiens, antioxydants et anti-inflammatoires de synthèse dans les formulations alimentaires et pharmaceutiques. Cependant, leur utilisation est limitée en raison de leur faible solubilité aqueuse, volatilité et sensibilité à la lumière. Notre travail de thèse porte sur la préparation et la caractérisation des vésicules lipidiques encapsulant l'HECG et l'Eug ainsi que les complexes d'inclusion cyclodextrine/Eug. Dans une première étape, la méthode d'injection éthanolique est utilisée à l'échelle du laboratoire où les paramètres de préparation ont été optimisés. Des phospholipides naturels de soja saturés (Phospholipon 80H et Phospholipon 90H) et insaturés (Lipoid S100) ont été utilisés pour étudier l'effet de l'hydrogénation et de la composition des phospholipides sur les caractéristiques des liposomes. Les conditions optimales ont été par la suite appliquées pour préparer les liposomes à grande échelle par contacteur à membrane et à l'échelle pilote. Des résultats similaires en termes de taille, indice de polydispersité, potentiel zêta, morphologie et taux d'incorporation de phospholipides sont obtenus à petite et grande échelle. Ceci indique la reproductibilité de ces procédés de préparation. Par ailleurs, des complexes d'inclusion d'HP-β-CD/Eug et d'HP-β-CD/HECG sont préparés dans une solution aqueuse et ensuite incorporés dans les liposomes formant un système combiné « drug in cyclodextrin in liposomes, DCL ». Un système en double encapsulation (DCL2) a été également préparé où l'Eug ou l'HECG sont ajoutés dans la phase organique et leurs complexes d'inclusion dans la phase aqueuse. En comparant à une simple incorporation dans les liposomes, DCL et DCL2 améliorent le rendement d'encapsulation de l'Eug et possèdent des tailles plus petites. Les résultats ont montré que les liposomes et les DCLs sont stables et maintiennent l'activité anti-oxydante de l'Eug. De plus, les liposomes protègent l'Eug contre la dégradation induite par les rayons UVC. Les DCLs, dont la particularité est de maintenir une huile essentielle volatile dans un lyophilisat en dépit des pressions très basses appliquées, peuvent être considérés comme un système de vectorisation prometteur de l'HECG et de l'Eug permettant leur utilisation en tant qu'ingrédients dans les préparations cosmétiques, pharmaceutiques, et agroalimentaires / Clove essential oil (CEO) and its major constituent eugenol (Eug) are recognized for their biological properties. These molecules may constitute natural alternatives to synthetic antimicrobial, antioxidant, and anti-inflammatory agents in food and pharmaceutical formulations. However, CEO constituents are volatile, sensitive to light and possess low aqueous solubility, which may limit their wide applications. Our thesis focuses on the preparation and characterization of lipid vesicles encapsulating CEO, Eug and the inclusion complexes cyclodextrin/Eug. In a first step, the ethanol injection method is applied at laboratory scale where the preparation parameters have been optimized. Natural hydrogenated (Phospholipon 80H, Phospholipon 90H) and non-hydrogenated (Lipoid S100) soybean phospholipids were used to study the effect of hydrogenation and phospholipid composition on the characteristics of liposomes. Optimal conditions were then applied to prepare liposomes at large scale by membrane contactor and at pilot scale. Similar results in terms of size, polydispersity index, zeta potential, morphology and phospholipid loading rate were obtained at laboratory and large scale. This indicates the reproducibility of the preparation methods. In addition, HP-β-CD/Eug and HP- β-CD/CEO inclusion complexes were prepared in aqueous solution and were then incorporated into liposomes forming a combined system « drug in cyclodextrin in liposomes, DCL ». Double loaded liposomes (DCL2) were also prepared where CEO or Eug were added in the organic phase and their inclusion complexes in the aqueous phase. Compared to CEO and Eug loaded liposomes, DCL and DCL2 improved the loading rate of Eug and possessed smaller vesicles size. Results showed that both liposomes and DCLs are stable and maintain the antioxidant activity of Eug. In addition, liposomes protect Eug from degradation induced by UVC irradiation. DCLs, whose characteristic is to keep a volatile essential oil in a lyophilized form despite the very low applied pressures, could be considered as a promising carrier system of CEO and Eug permitting their use as ingredients in cosmetic, pharmaceutical and food industries
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Influence of soil water management on plant growth, essential oil yield and oil composition of rose-scented geranium (Pelargonium spp.)Eiasu, B.K. (Bahlebi Kibreab) 17 October 2009 (has links)
Introducing effective irrigation management in arid and semi-arid regions, like most areas of South Africa, is an indispensable way of maximising crop yield and enhancing productivity of scarce freshwater resources. Holistic improvements in agricultural water management could be realised through integrating the knowledge of crop-specific water requirements. In order to develop effective irrigation schedules for rose-scented geranium (Pelargonium capitatum x P. radens), greenhouse and field experiments were conducted at the Hatfield Experimental Farm of the University of Pretoria, Pretoria, South Africa, from 28 October 2004 to 2006. Results from 20, 40, 60 and 80% maximum allowable depletion (MAD) levels of the plant available soil water (ASW) indicated that plant roots extracted most of the soil water from the top 40 cm soil layer, independent of the treatment. Both essential oil yield and fresh herbage mass responded positively to high soil water content. Increasing the MAD level to 60% and higher resulted in a significant reduction in herbage mass and essential oil yields. An increase in the degree of water stress apparently increased the essential oil concentration (percentage oil on fresh herbage mass basis), but its contribution to total essential oil yield (kg/ha oil) was limited. There was no significant relationship between MAD level and essential oil composition. For water saving without a significant reduction in essential oil yield of rose-scented geranium, a MAD of 40% of ASW is proposed. Response of rose-scented geranium to a one-month irrigation withholding period in the second or third month of regrowth cycles showed that herbage mass and oil yield were positively related. Herbage yield was significantly reduced when the water stress period was imposed during the third or fourth month of regrowth. A remarkable essential oil yield loss was observed only when the plants were stressed during the fourth month of regrowth. Essential oil content (% oil on fresh herbage mass basis) was higher in stressed plants, especially when stressed late, but oil yield dropped due to lower herbage mass. The relationship between essential oil composition and irrigation treatments was not consistent. Water-use efficiency was not significantly affected by withholding irrigation in the second or in the third month of regrowth. With a marginal oil yield loss, about 330 to 460 m3 of water per hectare per regrowth cycle could be saved by withholding irrigation during the third month of regrowth. The overall results highlighted that in water-scarce regions withholding irrigation during either the second or the third month of regrowth in rose-scented geranium could save water that could be used by other sectors of society. In greenhouse pot experiments, rose-scented geranium was grown under different irrigation frequencies, in two growth media. Irrigation was withheld on 50% of the plants (in each plot) for the week prior to harvesting. Herbage and essential oil yields were better in the sandy clay soil than in silica sand. Essential oil content (% oil on fresh herbage mass basis) apparently increased with a decrease in irrigation frequency. Both herbage and total essential oil yields positively responded to frequent irrigation. A one-week stress period prior to harvesting significantly increased essential oil content and total essential oil yield. Hence, the highest essential oil yield was obtained from a combination of high irrigation frequency and a one-week irrigation-withholding period. In the irrigation frequency treatments, citronellol and citronellyl formate contents tended to increase with an increase in the stress level, but the reverse was true for geraniol and geranyl formate. Leaf physiological data were recorded during the terminal one-week water stress in the glasshouse pot trial. Upon rewatering, stomatal conductance (Gs) and transpiration rate (Rt) were significantly lower in the less often irrigated than in the more often irrigated treatments, while leaf water potential (yw) and relative water content (RWC) were the same for all plants, indicating that water stress had an after-effect on Gs and Rt. At the end of the stress period, Gs, Rt, yw and RWC were lower in the plants from the more often irrigated than from the less often irrigated treatments. Irrespective of irrigation treatment, one type of non-glandular and two types (different in shape and size) of glandular trichomes were observed. In water stressed-conditions, stomata and trichome densities increased, while the total number of stomata and trichomes per leaf appeared to remain more or less the same. Water stress conditions resulted in stomatal closure. / Thesis (PhD)--University of Pretoria, 2009. / Plant Production and Soil Science / unrestricted
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Prospecção de produtos naturais para o manejo integrado de Lasioderma serricorne (Fabricius, 1792) (Coleoptera: Anobiidae) / Prospecting of natural products for the integrated management of Lasioderma serricorne (Fabricius, 1792) (Coleoptera: Anobiidae)Silva, Ana Paula Oliveira da 15 December 2017 (has links)
Lasioderma serricorne (F.) (Fabricius, 1792) (Coleoptera: Anobiidae) is
a cosmopolitan plague popularly known as a tobacco beetle that attacks a wide
variety of stored agricultural products, like soybeans, escavating galleries in the
grains while feeding and consequently generating losses to the producers by the loss
of quality and value of the seeds. Due to the risks of intoxication and environment
contamination with chemical residues, as well as the emergence of resistant
individuals, other approaches to the control of L. serricorne have been sought. The
host plant kairomones are molecules with potential for application as food attractants
in traps for monitoring and capture insects. On the other hand, the evaluation of
essential oils (EO) of native plants cultivated locally, can contribute to the discovery
of useful compounds as natural repellents or bio-insecticides, also generating tools
useful in integrated pest management (IPM). The objective of this study was to
investigate and identify the volatile organic compounds released by stored soybeans
from 3 varieties cultivated in Brazil with attractiveness to adults L. serricorne
(soybean marketed in large supermarket chains in Maceió-AL and two varieties
EMBRAPA BRS284 and BRS360RR) and to test the EO activity of the mature fruits
of Schinus terebinthifolius, in order to promote the prospection of natural compounds
with potential for application in the integrated management of this pest in storage
environments. The attractiveness of grains and extracts prepared by dynamic
headspace collection was evaluated in 4-arm olfactometer behavioral bioassays,
while the isolation and identification of the bioactive compounds were carried out
using gas chromatography coupled to electroanthennography (GC-EAG) and gas
chromatography coupled to mass spectrometry (GC-MS). Five EAG-active
compounds were identified in the extracts of soybeans: 1-octen- 3-ol, 3-octanol, 1-
nonanol, linalool and limonene. The behavioral response of L. serricorne in 4-arm
olfactometer bioassays to synthetic compounds was statistically significant for 1-
octen-3- ol, 3-octanol, 1-nonanol and linalool, while the attraction for the 4 synthetic
blend was comparable to that verified for soybeans. The activity of the EO extracted
by steam-drag of the mature fruits of S. terebinthifolius (3 replicates) harvested from
matrices located on the A. C. Simões Campus of UFAL, Maceió-AL, on L. serricorne
adults was tested in 4-arm olfactometer bioassays , in two concentrations (1 and 10
μL), while the EO composition was analyzed by GC-FID and GC-MS. EO repellency
was checked at a dose of 10 μL. A total of 14 compounds were identified in S.
terebinthifolius EO, with the main components being β-pinene (49.8%), α-pinene
(33.49%), 3-carene (5.85%), germacrene-D (2.08%) and bornylene (1.21%). The
attractive compounds identified from the soybean grains act as kayromones for L.
serricorne, while the S. terebinthifolius EO has repellent activity against this pest, so
the results obtained here can be applied in the development of bioproducts for the
integrated management of L. serricorne in and around storage environments,
favoring the rational use of insecticides. / Lasioderma serricorne (F.) (Fabricius, 1792) (Coleoptera: Anobiidae) é
uma praga cosmopolita conhecida popularmente como besourinho do tabaco que
ataca uma grande variedade de produtos agrícolas armazenados, dentre eles a soja,
escavando galerias nos grãos enquanto se alimentam e consequentemente gerando
prejuízos aos produtores pela perda da qualidade e valor das sementes. Devido aos
riscos de intoxicação e de contaminação do meio ambiente com resíduos químicos,
assim como o surgimento de indivíduos resistentes, outras abordagens para o
controle de L. serricorne tem sido buscadas. Os cairomônios das plantas
hospedeiras são moléculas com potencial para aplicação como atraentes
alimentares em armadilhas para monitoramento e captura de insetos. Por outro lado,
a avaliação de óleos essenciais (OE) de plantas nativas cultivadas localmente, pode
contribuir para a descoberta de compostos úteis como repelentes ou bioinseticidas
naturais, gerando também ferramentas úteis manejo integrado de pragas (MIP). O
objetivo desse estudo foi investigar e identificar os compostos orgânicos voláteis
liberados pelos grãos de soja armazenados de três variedades cultivadas no Brasil
com atratividade para adultos de L. serricorne (soja comercializada em grandes
cadeias de supermercados em Maceió-AL e duas variedades EMBRAPA BRS284 e
BRS360RR) e testar a atividade do OE dos frutos maduros de Schinus
terebinthifolius, a fim de promover a prospecção de compostos naturais com
potencial para aplicação no manejo integrado dessa praga em ambientes de
armazenamento. A atratividade dos grãos e de extratos preparados por coleta
dinâmica do headspace dos grãos foi avaliada em bioensaios comportamentais em
olfatômetro de 4 braços, enquanto o isolamento e identificação dos compostos
bioativos foram realizados pelas técnicas de cromatografia gasosa acoplada à
eletroantenografia (CG-EAG) e cromatografia gasosa acoplada à espectrometria de
massas (CG-EM). Cinco compostos EAG-ativos foram identificados nos extratos dos
grãos de soja: 1-octen- 3-ol, 3-octanol, 1-nonanol, linalol e limoneno. A resposta
comportamental de L. serricorne em bioensaios em olfatômetro de 4 braços aos
compostos sintéticos foi estatisticamente significativa para 1-octen- 3-ol, 3-octanol, 1-
nonanol e linalol, enquanto a atração pela mistura dos 4 compostos sintéticos foi
comparável à verificada para os grãos de soja. A atividade do OE extraído por
arraste a vapor dos frutos maduros de S. terebinthifolius (3 repetições) colhidos de
matrizes localizadas no campus A. C. Simões da UFAL, Maceió-AL, sobre adultos de
L. serricorne foi testada em bioensaios em olfatômetro de 4 braços, em duas
concentrações (1 e 10μL), enquanto a composição do OE foi analisada por CG-FID
e CG-EM. Foi verificada repelência do OE na dose de 10 μL. Foram identificados 14
compostos no OE de S. terebinthifolius, sendo os componentes principais: β-pineno
(49,8 %), α-pineno (33,49 %), 3-careno (5,85 %), germancreno-D (2,08 %) e
bornileno (1,21 %). Os compostos atrativos identificados a partir dos grãos de soja
atuam como cairomônios para L. serricorne, enquanto o OE de S. terebinthifolius
possui atividade repelente contra essa praga, portanto os resultados aqui obtidos
podem ser aplicados no desenvolvimento de bioprodutos para o manejo integrado
de L. serricorne dentro e ao redor de ambientes de armazenamento, favorecendo a
utilização racional de inseticidas.
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Avaliação da atividade antitumoral do óleo essencial da Mentha x villosa (Lamiceae) / Evaluation of the antitumor activity of the essential oil of Mentha x villosa (Lamiaceae)Amaral, Ricardo Guimarães 26 February 2014 (has links)
Cancer is the given name for a group of more than 100 diseases account for 13% of deaths worldwide and 15.1% in Brazil, with estimates of increased mortality. These data show the deficiency of more effective anticancer agents, leading to increased life expectancy or cure. In this context, nature is an alternative to the problem, for harboring a huge biodiversity and Brazil stands out for having the highest diversity of plant species in the world, but little explored as their biological characteristics. The genus Mentha has its very widespread species in the country, with many evidenced therapeutic activities, among them the potential anticancer action of essential oil (EO) demonstrated in two species (Mentha piperita e Mentha spicata). However, this study aimed to evaluate the antitumor activity of the essential oil of Mentha x villosa Hudson (OEMV) in vitro and in vivo, and its toxicity in vivo. For this, the EO was extracted from the leaves of Mentha x villosa, 12 of its constituents have been identified and their main constituent, the monoterpene rotundifolone was isolated. The in vitro cytotoxicity of OEMV rotundifolone and 3 were evaluated against tumor cell lines: ovarian adenocarcinoma (OVACAR-8), colon carcinoma (HCT-116) and glioblastoma (SF295) by the MTT assay. The OEMV showed cytotoxic activity in all cell lines tested, with IC50 ranging from 0.57 to 1.02 ìg/mL. However, rotundifolone did not show cytotoxicity at the tested concentrations, suggesting that the activity of the oil is not mediated by its major constituent. Considering this result, we evaluated the antitumor activity of OEMV in vivo using mice transplanted with sarcoma 180. In this study, it was showed antitumor activity in OEMV treatments performed by intraperitoneal (32.02 and 42.81% with 50 and 100 mg/kg/day, respectively) and orally (34.27 and 43.22% with 100 and 200 mg/kg/day, respectively), probably due to synergy among its constituents. No change was observed in the toxicological parameters evaluated in animals treated with OEMV: variation in body mass, organ weights (liver, spleen and kidney), blood biochemical parameters (AST, ALT, urea and creatinine) and ulcerative lesion index (this later only in the groups treated orally). Since the results demonstrated that OEMV has antitumor activity with low toxicity, it was proposed to evaluate the benefit of the association between OEMV (50 and 100 mg/kg/day) and 5-fluorouracil (5-FU, 10 mg/kg/day) reference known antineoplasic and toxicity. The association promoted tumor growth inhibition of 50.3% and 65.2% at doses of 50 and 100 mg/kg/day, respectively. The highest dose of OEMV in combination showed the same statistical difference that the level of inhibition of 5-FU at the highest dose (25 mg/kg/day). The toxicological parameters, variation of body mass and biochemical parameters (AST and ALT) showed alterations similar as the positive control. The organ weight alterations did not occur, a result that demonstrates an evident benefit of the combination compared to the group treated with 5-FU alone. The last toxicological endpoints evaluated were hematological parameters where both groups showed changes associated with differential count (lymphocytosis and neutropenia) and reduction in total leukocytes; positive factor in this result is that the reduction was not as intense as the one displayed by the control 5-FU furthermore possibly resulting in a decreased susceptibility to infection. The association promoted tumor growth inhibition 50.3% and 65.2% at doses of 50 and 100 mg/kg/day, respectively. The highest dose of OEMV in combination showed the same statistical difference that the level of inhibition of 5-FU dose (25 mg/kg/day) the toxicological parameters, variation of body mass and biochemical analysis (AST and ALT) showed alterations similar to the positive control. / O cancer e o nome dado a um conjunto de mais de 100 doencas, responsaveis por 13% das mortes no mundo e 15,1% no Brasil, com estimativas de mortalidade crescente. Esses dados refletem a carencia por agentes antineoplasicos mais efetivos, que levem ao aumento da expectativa de vida ou a cura. Nesse contexto, a natureza e uma alternativa para o problema, por abrigar uma gigantesca biodiversidade e o Brasil se destaca, por possuir a maior diversidade de especies de plantas do mundo, mas pouco exploradas quanto suas caracteristicas biologicas. O genero Mentha tem suas especies bem difundidas no pais, com diversas atividades terapeuticas comprovadas, dentre elas o potencial acao anticancer do oleo essencial (OE) comprovadas em duas especies (Mentha piperita e Mentha spicata). Portanto, o presente estudo teve como objetivo avaliar a atividade antitumoral do oleo essencial da Mentha x villosa Hudson (OEMV) in vitro e in vivo, e sua toxicidade in vivo. Para isso, o OE foi extraido a partir das folhas da Mentha x villosa, onde 12 dos seus constituintes foram identificados e isolado seu constituinte majoritario, a rotundifolona . A citotoxicidade in vitro do OEMV e da rotundifolona foi avaliada frente a 3 linhagens de celulas tumorais: adenocarcinoma ovariano (OVACAR-8), carcinoma de colon (HCT-116) e glioblastoma (SF295) atraves do ensaio do MTT. O OEMV apresentou atividade citotoxica em todas as linhagens de celulas testadas, com CI50 variando entre 0,57 e 1,02 Êg/mL. Porem, a rotundifolona nao demonstrou atividade citotoxica nas concentracoes testadas, sugerindo que a atividade do oleo nao e mediada por seu constituinte majoritario. Diante desse resultado, foi avaliada a atividade antitumoral do OEMV in vivo utilizando camundongos transplantados com sarcoma 180. Neste ensaio, o OEMV apresentou atividade antitumoral nos tratamentos realizados pela via intraperitoneal (32,02 e 42,81% com 50 e 100 mg/kg/dia, respectivamente) e pela via oral (34,27 e 43,22% com 100 e 200 mg/kg/dia, respectivamente), por provavel sinergismo entre seus constituintes. Nao foi observada nenhuma alteracao nos parametros toxicologicos avaliados em animais tratados com o OEMV: variacao de massa corporea, massa dos orgaos (figado, baco e rins), analises bioquimicas (AST, ALT, ureia e creatinina) e indice de lesao ulcerativa (este ultimo apenas nos grupos tratados por via oral). Como os resultados demonstraram que o OEMV possui atividade antitumoral, com baixa toxicidade, foi proposto avaliar o beneficio da associacao, via i.p, entre o OEMV (50 e 100 mg/kg/dia) e o 5-Fluorouracil em menor dose (5-FU, 10 mg/kg/dia), antineoplasico de referencia e conhecida toxicidade. A associacao promoveu a inibicao do crescimento tumoral de 50,3% e 65,2% nas doses de 50 e 100 mg/kg/dia, respectivamente. A maior dose do OEMV em associacao demonstrou a mesma diferenca estatistica que o indice de inibicao do 5-FU na maior dose (25 mg/kg/dia). Os parametros toxicologicos, variacao de massa corporea e analise bioquimica (AST e ALT) apresentaram alteracoes semelhantes as do controle positivo. Na massa dos orgaos nao ocorreu alteracao, resultado que demonstra um evidente beneficio da associacao quando comparada ao grupo tratado com 5-FU isolado. O ultimo parametro toxicologico avaliado foram as analises hematologicas onde ambos os grupos associados demonstraram alteracoes na contagem diferencial e reducao na contagem de leucocitos totais; o fator positivo nesse resultado e que a reducao nao foi tao intensa quanto a apresentada pelo controle positivo 5-FU, provocando possivelmente, uma menor susceptibilidade a infeccoes. Diante dos resultados, podemos afirmar que o OEMV tem atividade antitumoral in vitro e in vivo com baixa toxicidade, e que a associacao entre 5-FU e o OEMV potencializa a atividade antitumoral do antineoplasico, diminuindo alguns dos seus efeitos toxicos.
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