Ledebouria ovatifolia (Bak.) lessop, Clivia caulescens R.A.Dyer and Haemanthus pauculifolius Snijman & Van Wyk were the three species investigated in this work. Ledebouria ovatifolia belongs to the family Hyacinthaceae (Liliaceae sensu lato) and, to date, the chemical composition of this species has not been investigated. Members of this family are widely distributed, but are particularly well represented in Southern Africa. The Ledebouria genus was formerly classified as part of the Scilla genus from which a large number of naturally occurring oxygen heterocycles known as homoisoflavonoids have been isolated. In this work the bulbs of L. ovatifolia were investigated and two compounds were isolated. These were the homoisoflavonoid, 5,7-dihydroxy-3-(4'-hydroxybenzyl)-4-chromanone and the chalcone, 6',2'-dimethoxy-4,4'dihydroxychalcone, both of which are known naturally occurring compounds. Clivia caulescens and Haemanthus pauculifolius are both members of the Amaryllidaceae family. The plants of the Amaryllidaceae family form a large group of over sixty genera, which are concentrated mainly in Southern Africa. Plants from this family have been extensively used in traditional medicines and many have pharmacological properties. The compounds responsible for most of these effects are a group of isoquinoline alkaloids, which are found almost exclusively in plants belonging to this family. The alkaloids isolated from plants belonging to this group are known to cause poisoning in low doses and can cause excessive salivation and diarrhoea. Higher doses of the active compounds can cause CNS depression and large enough doses can prove fatal. Although many of these alkaloids are harmful to man, some of the unique Amaryllidaceae alkaloids exhibit anti-tumour and anti-viral activities, and are thus potentially beneficial to man. The Clivia genus is endemic to South Africa and the most common species, C. miniata, is used by traditional healers to facilitate childbirth and as a snake bite remedy. In this chemical investigation both the bulbs and the leaves of C. caulescens were investigated. The ethanol extract of the bulbs yielded four alkaloids, hippeastrine, haemanthamine, lycorine and ll-(S)-hydroxyvittatine. The investigation of the leaf extract also yielded lycorine and hippeastrine as well as an additional alkaloid sternbergine. Haemanthus pauculifilius is a recently described member of the Haemanthus genus, which consists of 27 taxa that are restricted to Southern Africa and Namibia. In this chemical investigation the ethanol extract of the bulbs and leaves yielded the common triterpenoid sitosterol as well as two novel 5,11-methanomorphanthridine type alkaloids, montanine hydrochloride and manthidine. / Thesis (M.Sc.)-University of Natal, Durban, 1999.

L'objectif de la thèse est de contribuer à l'explicitation du lien au terroir, dans le cas de vins d'Appellation d'Origine Contrôlée. À ce lien au terroir correspond une typicité, qui correspond à des propriétés remarquables et partagées pour un groupe humain de référence. Le lien causal entre typicité et terroir a été étudié en prenant comme élément d'étude le chantier de vendange et les vinifications associées. La composition phénolique des vendanges, et leur aptitude à être extraits lors de la vinification ont permis de mieux interpréter le lien causal étudié. La représentation conceptuelle de la typicité, qui engendre des choix techniques, a été mise en évidence, du point de vue des critères sensoriels d'appartenance et des critères sensoriels de distinction. Cette représentation conceptuelle est en générale consensuelle, et les principaux facteurs du terroir, explicatifs du lien, correspondent au milieu physique. La représentation perceptuelle a été étudiée, permettant de mettre en évidence des descripteurs d'appartenance et de distinction, et de les hiérarchiser vis à vis de la perception globale de la typicité. Cette représentation est moins consensuelle. Les principaux facteurs du terroir, explicatifs du lien, correspondent aux actes techniques, en particulier la date de vendanges et la durée de cuvaison.Une évolution de la composition de la vendange en fonction du niveau de maturité a été mise en évidence d'un point de vue histologique, mais son interprétation est incomplète. L'aptitude des proanthocyanidines à être extraits, en fonction du niveau de maturité des baies est fortement corrélé à la perception globale de la typicité. Dans le cas de vins revendiquant un lien au terroir, certaines représentations de la typicité sont partagées, et engendrent des choix techniques (date de vendange, durée de cuvaison). L'importance de ces choix peut être démontré par l'étude de la composition de la vendange en composés phénoliques. Cependant, il existe un écart entre la typicité en tant que concept et la typicité telle qu'elle est sensoriellement perçue. / The aim of this work is to contribute to highlight the terroir effect, in the case of wines from delimited origin. The typicality is the result of the terroir effect and corresponds, to remarkable and shared properties for a human group of reference. The causal link between typicality and terroir was studied by taking into account the harvest date and the associated wine makings. The phenolic composition of the grape at harvest, and their extractability during the wine making made it possible to better interpret the studied causal link. The conceptual representation of the typicality, which generates technical choices, was highlighted, from the point of view of the sensory criteria of similarity and of distinction. This conceptual representation is in general consensual, and the main factors of the terroir, which explain the causal link, correspond to the soil and climate. The perceptual representation was studied, descriptors of similarity and distinction were highlighted, and theses descriptors were organized with respect to the global perception of the typicality. This representation is less consensual than conceptual one. The main factors of the terroir, which explain the causal link, correspond to the technical acts, particularly the harvest date and the vatting duration.Composition of the harvest, according to the level of maturity was highlighted from a histological point of view, but its interpretation was unfinished. The aptitude of the proanthocyanidins for being extracted, according to the level of maturity is strongly correlated for the global perception of the typicality. For wines related to terroir, some typicality representations are shared, and lead to technical choices (harvest date, duration of vatting). These choices are explained by the harvest composition. However, there is a difference between the typicality as a concept and the typicality as sensory perception.

Charles University in Prague, Faculty of Pharmacy in Hradec Králové Department of Pharmacognosy Candidate: Hana Novotná Supervisor: PharmDr. Marie Kašparová, Ph.D. Title of diploma thesis: Secondary metabolites of plant tissue culture of Trifolium pratense L. Explant cultures are perspective sources of secondary metabolites. Nevertheless production of flavonoids and isoflavonoids by the suspension culture of Trifolium pratense L. is not high. Elicitation is one of the methods used to enhance the biosynthesis of secondary metabolites. Elicitation induces physiological changes, stimulates defensive or stress-induced reactions in plants and subsequently triggers the synthesis of secondary metabolites. The objective of this study was to observe the influence of two elicitors - abscisic acid and ascorbic acid - on the production of flavonoids and isoflavonoids by the Trifolium pratense L. suspension culture (Sprint variety). The culture was cultivated in Gamborg medium to which 2 mg.l-1 of 2,4- dichlorophenoxyacetic acid and 2 mg.l-1 of 6-benzylaminopurine were added, at the temperature of 25 řC and 16 hours light / 8 hours dark period. The best elicitation effect of abscisic acid on the production of flavonoids and isoflavonoids was observed after a 6-hour application of the highest 500 µmol.l-1...

The use of food supplements containing natural chemopreventive compounds increased in recent years. Some of the most popular chemopreventive compounds are flavonoids. Due to their natural origin, flavonoids are generally accepted as safe compounds. They exert antioxidant, anti-cancer and anti-inflammatory properties. However, flavonoids should be considered as foreign compounds (xenobiotics). Flavonoids interact with many enzymes, among the most important belong cytochromes P450 (CYPs), key enzymes of the first phase of biotransformation of xenobiotics (e.g. drugs, carcinogens). CYPs catalyze reactions leading mainly to detoxification of xenobiotics. However, some CYPs are involved in the activation of carcinogens, particularly CYP1A1 and CYP1A2 activate e.g. heterocyclic amines. Flavonoids might enhance the activation of carcinogens via induction of these CYPs or stimulation of their activities and hence, increase the risk of a cancer development. The thesis is focused on the influence of flavonoids and food carcinogens on the induction and activity of CYP1A1 and CYP1A2 in liver and small intestine of rats. For the purpose of this study, the small intestine was dissected into three parts: proximal (nearest to stomach), middle and distal. Western blotting was used for the evaluation of CYP...

The general aim of the thesis was to deduce whether selected naturally occurring flavonoids (genistein, epicatechin gallate (EC), epigallocatechin gallate (EGCG), baicalin) attenuate various secondary insults that may cause death of ganglion cells in primary open angle glaucoma (POAG). An ischemic insult to the rat retina significantly causes the inner retina to degenerate indexed by changes of various antigens, proteins and mRNAs located to amacrine and ganglion cells. These changes are blunted in animals treated with genistein as has been shown for ECGC. Studies conducted on cells (RGC-5 cells) in culture showed that hydrogen peroxide, L-buthionine sulfoximine (BSO)/glutamate and serum deprivation (mimicking oxidative stress), rotenone, sodium azide (affecting mitochondria function in specific ways) and light (where the mitochondria are generally affected) all generated reactive oxygen species and caused death of RGC-5 cells. EGCG was able to attenuate cell death caused by hydrogen peroxide, sodium azide and rotenone. Only EC was able to attenuate BSO/glutamate-induced cell death, in addition to cell death caused by hydrogen peroxide and rotenone. Genistein had no positive effect on cell death in experiments carried out on RGC-5 cells. Exposure of RGC-5 cells to flavonoids showed that EC and EGCG increased the mRNA expression of endogenous antioxidants such as HO-l (heme oxygenase 1) and Nrf-2 (nuclear erythroid factor-z-related factor 2). Light insult, rotenone and sodium azide activate the p38 (protein kinase 38) pathway, while only light and rotenone activate the JNK (c-Jun amino-terminal kinase) pathway. Serum deprivation affects mitochondrial apoptotic proteins causing an increase in the ratio of Bax/Bcl2 (Bax: Bcl-2-associated X protein; Bcl-2: B-cell lymphoma 2). An insult of light to RGC-5 cells, unlike that induced by sodium azide, is inhibited by necrostatin-I and causes an activation of AlF (apoptosis-inducing factor) with alpha-fodrin being unaffected. These studies suggest that ganglion cell death caused by insults as may occur in POAG involves various cellular signaling pathways. The selected flavonoids have diverse actions in increasing cellular defense mechanisms, and in negating the effects of ischemia and specific types of oxidative stress. The results argue for the possible use of flavonoids in the treatment of POAG to slow down ganglion cell death.

Les flavonoïdes sont des composés naturels appartenant à la famille des polyphénols, qui sont étudiés depuis de nombreuses années pour leur caractère antioxydant ainsi que leurs propriétés thérapeutique. La mise en évidence, pour certaines d’entre eux, d’une activité vasorelaxante variant en fonction de leur structure, en fait un modèle d’étude de choix pour la prévention des maladies cardiovasculaires. Le 3’,4’-dihydroxyflavonol (DiOHF) est le dérivé le plus décrit pour son fort potentiel en terme de propriétés cardioprotectrices et antioxydantes et est considéré comme un composé d’intérêt dans le traitement anti-ischémique, bien que sa faible solubilité dans l’eau soit un facteur limitant pour son utilisation. Dans ce contexte, notre premier objectif a été de synthétiser une trentaine de dérivés du DiOHF, fonctionnalisés par un groupement hydrophile, tout en préservant ses propriétés antioxydantes et pour certaines des structures obtenues, ses propriétés vasorelaxantes. Pour cela, nous avons développé une méthode de synthèse rapide utilisant les irradiations micro-onde, qui nous a permis d’optimiser les rendements, de réduire les temps de réaction et qui ne conduit à aucune formation de sous-produits. Notre second objectif a été de déterminer l’activité antioxydante de ces dérivés flavonoïques par des tests mettant en œuvre des réactions de compétition avec des radicaux libres. Faisant suite à ce premier screening, des études biologiques chez le rat ont été réalisées sur les composés montrant les meilleures performances. A partir d’essais in vitro et in vivo nous avons démontré, l’innocuité de ces dérivés flavonols, et le fort impact des modifications de structure sur l’activité vasorelaxante et antioxydante, ainsi que sur la récupération fonctionnelle et métabolique consécutive à une ischémie/reperfusion myocardique. Un autre champ d’action de ces flavonols hydrosolubles pourrait être d’explorer leur utilisation dans le traitement du diabète de type 2. Pour cela nous avons greffé deux motifs antidiabétiques, correspondant à des molécules actives déjà utilisées dans le traitement de l’insulinorésistance, sur les dérivés flavonols les plus cardioprotecteurs et/ou vasorelaxants de notre série, ainsi que sur des dérivés de l’acide cinnamique. Ces composés ont été testés pour leur activité antioxydante, laissant supposer un potentiel significativement supérieur aux analogues antidiabétiques non fonctionnalisés, en termes de protection antioxydante et fonctionnelle. / Flavonoids are natural polyphenolic compounds, and epidemiological and pharmacological studies have shown that flavonoids intake is associated with many beneficial effects. An important example is the 3’,4’-dihydroxyflavonol (DiOHF) which showed interesting therapeutic properties in vitro so it could be considered as an important lead compound to the treatment of cardiovascular diseases. However is poor water solubility prevents it use as a drug. Starting from this model we have synthesized a series of new flavones functionalized by a hydrophilic group in order to increase water solubility. To obtain these derivatives we have set up a fast, simple and clean method without formation of by-products, using micro-waves irradiation to optimize yield and to decrease reaction time. Our second purpose was to investigate the antioxidant activity of the synthesized compounds by undergoing several assays. The most promising compounds were tested in biological studies, in vitro and in vivo. The results showed a significant enhancement of the post-ischemic mechanical function recovery in vivo and in vitro. Another purpose was to designed new flavonols linked to selected antidiabetic moieties already used in the treatment of insulinoresistance. It was shown that these new compounds retain the antioxidant properties of the parent flavonols, and can be of interest in the development of new diabete 2 treatments.

O cupuaçu é uma fruta nativa brasileira, com boa palatabilidade e grande potencial agroindustrial, seja na produção de polpa congelada, seja na de um produto análogo ao chocolate, o cupulate®. Polpas frescas de cupuaçu apresentaram composição centesimal e teor de fenólicos similares ao longo do ano, favorecendo sua industrialização. Esta regularidade também foi observada entre as distintas marcas avaliadas de polpa de cupuaçu congelada. Foi verificado, porém, diminuição de fenólicos, capacidade antioxidante e inibitória de α-amilase da polpa congelada em relação à polpa fresca. Esta enzima foi inibida pela polpa deste fruto; no cupulate não foi detectada nenhuma inibição de α-amilase ou de α-glicosidase. O cupulate apresentou, aproximadamente, metade da capacidade antioxidante, do teor de fenólicos e de proantocianidinas totais do chocolate. Apresentou, ainda, menor teor de proteínas e maior teor de lipídios que o chocolate. Os ácidos graxos presentes em maior quantidade na semente de cupuaçu, tanto fresca como processada (líquor), são o oléico e o esteárico. Os efeitos do processamento das sementes de cupuaçu assemelham-se àqueles observados no cacau: grande perda de umidade, aumento de lipídios, redução de carboidratos e do teor de polifenólicos. O decréscimo destes compostos ocorre, possivelmente, devido à sua condensação oxidativa, gerando taninos insolúveis de alto peso molecular. Os flavonóides identificados no cupuaçu foram catequina, epicatequina, theograndinas e glucuronídeos de isorhamnetina, quercetina e luteolina. Foram, ainda, identificados procianidinas até decâmeros na semente fresca de cupuaçu, já no líquor, devido à baixa concentração, somente até tetrâmeros. / Cupuassu is a brazilian native fruit, with good flavor and great industrial potential, either in the production of frozen pulps or in the manufacturing process of a chocolate-like food, the cupulate®. Cupuassu\'s fresh pulp showed similar chemical composition and phenolics content over the year, supporting its industrialization. This regularity was also observed between different brands of cupuassu frozen pulp. It was found, however, that the processed pulp has a decrease on phenolics content, antioxidant capacity and α-amylase inhibitory activity, in relation to the fresh pulp. This enzyme was inhibited by the fruit pulp. Cupulate, on the other hand, did not inhibit either α-amylase or α-glucosidase. This product showed, approximately, half of the antioxidant capacity, of the total phenolics content and of the total proanthocyanidins content found in the regular chocolate. Cupulate showed, also, less proteins content and more lipids content than chocolate. The most abundant fatty acids, either in the cupuassu\'s fresh seed or in the processed seed (liquor), were the oleic acid and stearic acid. The processing effects observed in the cupuassu\'s seeds were similar to those observed in cocoa processing, i.e. high moisture reduction, lipids increase, carbohydrate and phenolics content reduction. The phenolics decrease occurs, possibly, due to oxidative condensation, yielding unsoluble tannins of high molecular mass. The flavonoids identified on cupuassu were catechin, epicatechin, theograndins and glucuronides of isorhamnetin, quercetin and luteolin. Procyanidins up to decamers on the cupuassu\'s fresh seeds were also identified, but only up to tetramers on cupuassu\'s liquor, due to the their low concentration.

A Lesão Renal Aguda (LRA) é a complicação mais grave da rabdomiólise. Nessa síndrome, a liberação do pigmento heme desencadeia uma lesão que se caracteriza por vasoconstrição glomerular e toxicidade celular direta com componente oxidativo. A lesão oxidativa desencadeada é uma das linhas fisiopatológicas mais intrigantes. A renoproteção com antioxidantes tem demonstrado efeito satisfatório. As proantocianidinas são antioxidantes naturais encontrados no extrato da semente da uva. O objetivo deste estudo foi avaliar o efeito antioxidante da Vitis vinifera (extrato da semente de uva) sobre a função renal de ratos submetidos à lesão por rabdomiólise. Foram utilizados ratos Wistar, adultos machos, pesando entre 250-300 gramas. A LRA foi induzida pela administração de glicerol 50% i.m (intramuscular). Os animais foram distribuídos em 4 grupos: grupo Salina (6ml/Kg de NaCl 0,9% via intraperitoneal (i.p) 1 vez ao dia), grupo Glicerol (6ml/Kg de glicerol i.m, cada região femoral recebeu 3ml/Kg de glicerol, 1 vez ao dia), grupo Vitis vinifera (3mg/Kg v.o por 5 dias) e grupo Glicerol+Vitis vinifera que recebeu Vitis vinifera por 5 dias antes do glicerol. Foram avaliados o marcador de lesão muscular (CK), a função renal (FR), a função tubular (FENa e FEK), o perfil oxidativo (peróxidos urinários-FOX-2 e MDA-TBARS) , a histologia e morfometria renal. O grupo Glicerol tratado com Vitis vinifera apresentou melhora da FR e tubular, redução dos níveis da peroxidação lipídica e melhora da histologia renal. Os resultados deste estudo confirmaram a proteção antioxidante, com repercussão histológica, da Vitis vinifera na LRA induzida por glicerol. / The Acute Kidney Injury (AKI) is the worst complication of rhabdomyolysis. In this syndrome, the delivery of heme pigment induces an injury that distinguishes itself by glomerular vasoconstriction and direct cellular toxicity with oxidative component. The oxidative injury is an intriguing one of the pathophysiological mechanism. The renoprotection with antioxidants has demonstrated satisfactory effect. The proanthocyanidins are natural antioxidants found in grape seed extract. The aim of this study was to evaluate the antioxidant effect of Vitis vinifera (grape seed extract) on the renal function of rats submitted to the injury by rhabdomyolysis. Wistar rats, male, adults, weight ranging from 250-300 g were used. The AKI was induced intramuscular (i.m.) administration of glycerol 50%. The animals were distributed in 4 groups: Saline group (6ml/Kg of NaCl 0,9% intraperitoneal (i.p) once a day), Glycerol group (6ml/Kg of glycerol i.m, each femoral region received 3ml/Kg of glycerol, once a day), Vitis vinifera group (3mg/Kg v.o by 5 days) and Glycerol+Vitis vinifera group that has received Vitis vinifera by 5 days before glycerol. Marker of muscular injury (CK), renal function (RF), the tubular function (FENa and FEK), the oxidative profile (urinary peroxides -FOX-2 and MDA-TBARS), the histological and kidney morphometric were evaluated. The Glycerol group treated with Vitis vinifera has shown improvements in RF and tubular, reduction of levels of lipid peroxidation and amelioration of kidney histology. The results of this study have confirmed the antioxidant protection, with histological repercussion of Vitis vinifera in AKI induced by glycerol.

O gênero Passifloraceae possui mais de 400 espécies, sendo uma delas Passiflora incarnata L., detentora de diversas aplicações , principalmente no âmbito farmacêutico como uma planta capaz de atuar no sistema nervoso central para o tratamento de distúrbios da ansiedade. As substâncias mais abundantes existentes nas folhas dessa espécie pertencem à classe dos flavonóides, principalmente os C-glicosilados, que podem estar diretamente relacionados à atividade farmacológica da planta. Assim, o objetivo do presente trabalho , foi avaliar a influência (ou não ) de fatores externos na concentração dos flavonóides, em um cultivo experimental realizado na região de Botucatu .Os flavonóides analisados foram a luteolina, homoorientina, vitexina, isovitexina e orientina , com sua quantificação realizada por HPLC-UV/DAD e expressos em flavonóides totais calculados com base no padrão de rutina, através do método descrito por Pereira (2002). Realizou-se a correlação quimiométrica destes resultados pela análise multivariada , através de PCA (análise de componentes principais ) e HCA (análise hierárquica de agrupamentos), para avaliar se ocorreu a influência direta de determinados elementos do solo (pH, macronutrientes e micronutrientes) e do ambiente (temperatura e umidade) no teor de flavonóides encontrados nas folhas. Concluiu-se que as amostras se apresentaram de forma heterogênea no decorrer do cultivo (quanto à classificação ) , porém que alguns minerais presentes no solo (por exemplo, ferro, boro e cobre ), possuem relação inversa à concentração dos flavonóides totais encontrados nas folhas de P. incarnata. / Passifloraceae genus has more than 400 species and one of them is Passiflora incarnata L., which holds different application, mainly on the pharmaceutical scope as an herb capable to act on the central nervous system to the treatment of anxiety disturbs. The more copious compounds that exist on the leaves of this specie belong to flavonoid category, mainly C-glicosilates that could have direct relationship with pharmacologic properties of the herb. So, the objective of this task was to evaluate concentration in experimental growth made on Botucatu?s place. Analysed flavonoids were luteolin, homoorientin, vitexin, isovitexin and orientin, which were quantified by HPLC-UV/DAD and expressed as total flavonoids as rutin, through described method from Pereira (2002). Results were analysed through chemometric´s correlation, with PCA (principal components analysis) and HCA (hierarchic clusters analysis), to evaluate if some soil members (pH, macro and micronutrients) and ambient members (temperature and humidity) affected or not the flavonoids content on the leaves. It was conclude that all samples appeared heterogeneous in the course of growth, but some members present on the soil (as example iron, cupper and bore), have opposite relationship with total flavonoids content on the leaves of P. incarnata.

A própolis é conhecida por suas atividades biológicas, tais como antioxidante, antimicrobiana, antinflamatória, antiviral, entre outras. Sua composição varia entre regiões e existe grande diversidade química entre os diferentes tipos de própolis. Os principais constituintes da própolis são os compostos fenólicos, os quais são responsáveis por várias atividades biológicas, como a atividade antioxidante. Um novo tipo de própolis, nunca antes relatado na literatura, denominado própolis vermelha em decorrência de sua coloração intensa característica, foi coletado na região de mangue do Estado de Alagoas. Este trabalho teve como objetivo avaliar a composição química e fracionar e isolar compostos com atividade antioxidante da própolis vermelha brasileira. O extrato etanólico da própolis vermelha (EEP) foi primeiramente fracionado pela técnica de extração líquido-líquido, originando as frações hexânica (fr-Hex) e clorofórmica (fr- Clo). A fr-Clo apresentou alto rendimento e composição química complexa, sendo, então, recromatografada em coluna aberta de sílica-gel, gerando 15 subfrações. O EEP, frações e subfrações foram avaliados quanto à sua composição química e atividade antioxidante para seleção das frações destinadas ao isolamento bioguiado. O EEP também foi analisado pela técnica de cromatografia gasosa acoplada à espectrometria de massas (CG-EM), tendo sido identificados sete compostos nunca antes relatados em própolis brasileira, entre os quais, quatro isoflavonóides. Os teores de compostos fenólicos totais e de flavonóides, testados para o EEP, frações e subfrações, variaram de 37,4 a 324,2 mg/g e de 0,0 a 158 mg/g, respectivamente. Com relação ao potencial antioxidante, a maior atividade de seqüestro do radical DPPH foi encontrada para a fr- Hex, enquanto a subfração 5 apresentou alto rendimento e boa atividade pelo método do sistema β-caroteno/ácido linoléico, tendo sido estas frações selecionadas para o isolamento dos compostos bioativos por Cromatografía Líquida de Alta Eficiência (CLAE) preparativa. Três compostos, um da fr-Hex e dois da subfração 5, foram isolados e analisados por CG-EM. Os compostos da subfração 5 foram identificados como 2',7-diidroxi-4'metoxiisoflavana (vestitol) e 2',4'-dihidroxi-7 metoxiisoflavana, ambos isoflavonóides. Não foi possível identificar o composto da fr-Hex utilizando somente a técnica de CG-EM, embora tenha sido possível verificar que este é uma mistura de dois isômeros com peso molecular de 466 g/mol. Os resultados obtidos demonstram que a própolis vermelha é uma boa fonte de compostos bioativos, dentre os quais encontramse isoflavonas, que possuem atividade antioxidante. / Propolis is known for its wide range of biological activities, such as antioxidant, antibacterial, anti-inflammatory, antiviral, among others. Its composition varies according to the region where it is collected and there is a great chemical diversity among the different types of propolis. The main constituents of propolis are the phenolic compounds, which are responsible for several biological activities, such as the antioxidant activity. A novel type of propolis, which has never been reported in the literature before, named red propolis due to its intense characteristic color, was collected in a mangrove area in the state of Alagoas. This study aimed to evaluate the chemical composition, and fractionate and isolate the compounds with antioxidant activity of Brazilian red propolis. The Ethanolic Extract of Propolis (EEP) was first fractionated using the liquid-liquid extraction technique, yielding the hexanic (Hex-fr) and the chloroformic fractions (Chlo-fr). Chlo-fr showed great yield and a complex chemical composition and therefore was refractioned in silica gel open column, yielding 15 subfractions. The EEP, fractions and subfractions were evaluated for their chemical composition and antioxidant activity aiming to select the fractions destined for bioguided isolation. The EEP was also analyzed by the gas-chromatography-mass spectrometry (GC-MS) technique, and seven compounds, never reported for Brazilian propolis before, were identified, among which are four isoflavonoids. The amounts of total polyphenol and flavonoid compounds, tested for EEP, fractions and subfractions, ranged from 37,4 to 324,2 mg/g and 0,0 to 158 mg/g, respectively. The major free radical (DPPH) scavenging activity was found for Hex-fr, while subfraction 5 showed high yield and good antioxidant activity by β-carotene/linoleic acid system oxidation, and these fractions were selected for isolation of bioactive compounds by preparative High Performance Liquid Chromatography (HPLC). Three compounds, one from Hex-fr and two from subfraction 5, were isolated and analyzed by GC-MS. The compounds from subfraction 5 were identified as 2',7-diidroxi- 4'metoxiisoflavan (vestitol) and 2',4'-dihidroxi-7 metoxiisoflavan, both isoflavonoids. It was not possible to identify the compound from Hex-fr using GC-MS, although it was possible to verify that this compound is a mixture of two isomers presenting molecular weight of 466 g/mol. The results obtained in this study demonstrate that red propolis is a good source of bioactive compounds, among which are isoflavonoids, compounds that possess antioxidant activity.