999 resultados para compostos fenólicos totais


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O objetivo deste trabalho foi desenvolver e avaliar diferentes formulações de sorbets probióticos e simbióticos a base de polpa de juçara (Euterpe edulis), de modo a combinar os efeitos benéficos à saúde dos compostos fenólicos deste fruto com os benefícios dos probióticos e prebióticos. Para isso, foram utilizados os microrganismos L. acidophilus e L. paracasei e a fibra polidextrose, além da elaboração de uma amostra controle sem tais elementos para efeito de comparação. Primeiramente, a polpa de juçara pasteurizada utilizada na produção dos sorbets foi avaliada de acordo com suas características físico-químicas e seus compostos bioativos, tendo apresentado resultados adequados para o emprego na matriz alimentícia em questão. Em seguida, os sorbets foram caracterizados através de diversos parâmetros. Assim, a análise centesimal mostrou sorbets com alto índice de carboidratos e baixo valor calórico, enquanto os teores de sólidos solúveis apresentaram-se coerentes em todas as formulações analisadas. Os valores de overrun e densidade aparente relevaram que a incorporação de ar dos sorbets não foi tão elevada quanto de um sorvete lácteo, embora as amostras adicionadas de polidextrose - capaz de mimetizar as propriedades de corpo e espessamento da gordura - tenham obtido resultados mais próximos aos gelados tradicionais. Foram ainda mensurados os efeitos do armazenamento dos produtos a -18 °C durante 120 dias, através de avaliações de pH, coloração instrumental, estabilidade dos compostos fenólicos e antocianinas e viabilidade dos probióticos. O pH das amostras manteve-se constante durante todo o experimento, com valores entre 4,4 e 4,8, enquanto os parâmetros de coloração caracterizaram as amostras como vermelhas e apontaram tendência à perda de luminosidade. Já os polifenóis e antocianinas apresentaram teores elevados, decorrentes da adição da polpa de juçara, sem a ocorrência de degradação destes compostos ao longo da estocagem das amostras sob congelamento. As populações de ambos os microrganismos adicionados apresentaram-se estáveis em cerca de 8 log UFC/ g durante todo o período de armazenamento, o que corresponde a um resultado bastante satisfatório e superior ao recomendado pela legislação brasileira. Por outro lado, a sobrevivência in vitro de tais probióticos quando submetidos aos fluidos gastrointestinais não apresentou resultados adequados para a garantia da funcionalidade destes produtos, com queda de viabilidade superior a 4 ciclos logarítmicos. A aceitabilidade sensorial e intenção de compra apresentaram resultados positivos para todas as formulações, com maior aceitação das amostras probióticas em relação ao controle e menor interesse pelas amostras com adição de prebiótico. Tal resultado demonstra que a incorporação destas bactérias em sorbets de juçara é capaz de melhorar a qualidade do produto, enquanto a adição de polidextrose pode diminuir sua aceitabilidade nas condições empregadas. Em síntese, os sorbets elaborados apresentaram resultados satisfatórios, demonstrando a viabilidade na produção deste tipo de alimento funcional adicionado de probióticos, prebiótico e rico em polifenóis, sendo a combinação de tais elementos capaz de potencializar os efeitos benéficos destes compostos e trazer vantagens fundamentais à microbiota intestinal e à saúde de quem os consome.

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Os grãos de quinoa possuem excelente balanço nutricional além das propriedades funcionais, comparativamente superior à dos cereais. A quinoa é cultivada em diversos países e, devido às suas características, têm aumentado o interesse de pesquisadores e consumidores. A quinoa contém pericarpo branco, no entanto, existem grãos com pericarpo vermelho e preto, e todos os tipos são utilizados como alimento em diferentes preparações. Com o objetivo de avaliar as características de grãos de quinoa, amostras de cor branca, preta e vermelha foram analisadas quanto às propriedades físico-químicas e funcionais dos grãos e do amido extraído das diferentes amostras. O amido, extraído pelo método alcalino, foi submetido as análises de teor de amilose, difração de raios X, microscopia eletrônica de varredura (MEV), propriedades térmicas (por DSC-Differential Scanning Calorimeter) e propriedades de pasta (por RVA- Rapid Visco Analyser), além de suscetibilidade à hidrólise enzimática e cor. A composição físico-química dos grãos de quinoa apresentou como principais diferenças o teor de cinzas, fibras e amido. O teor de amilose variou de 13,6% a 21,3%, entre as amostras de amido; os padrões de cristalinidade dos amidos foram de tipo A, típico dos cereais; e, a cristalinidade relativa variou de 25,4 a 29,6 %; as micrografias obtidas por MEV apresentaram as formas poliédricas dos grânulos de amido. Os viscoamilogramas, obtidos para os diferentes amidos, mostraram um comportamento semelhante entre as amostras brancas e pretas. As propriedades térmicas de retrogradação das amostras de quinoa vermelha apresentaram uma menor taxa de retrogradação que variou de 7,5 a 8,5 %; as cultivares brancas apresentaram as maiores taxas de retrogradação de 19,0 a 25,4 %. A hidrólise enzimática dos grânulos de amido, analisada em equivalentes de maltose, variou de 7,2 a 8,7 mg/mL, com uma velocidade maior para a cultivar BSyB, em 60 minutos. O amido extraído das amostras brancas de quinoa apresentou valor de luminosidade de 99,0 e os amidos extraídos das amostras de cor vermelha e preta apresentaram em torno de 97,0. As análises realizadas neste estudo ampliam o conhecimento das características da quinoa de cor branca, vermelha e preta, além de mostrar que a cultivar brasileira (BSyB) apresenta características diferenciadas em vários parâmetros. Devido as suas propriedades todas as amostras analisadas possuem potencial para futuras aplicações tecnológicas.

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A tecnologia anaeróbia tem sido utilizada com sucesso no tratamento de água residuária contendo compostos fenólicos. Recentes pesquisas incluem tais compostos entre aqueles que podem ser degradados através desse processo. O objetivo desse trabalho foi avaliar a degradação do fenol em diferentes condições nutricionais, com ênfase na redução do sulfato. Os experimentos foram realizados com meio de cultura específico para esses microrganismos anaeróbios. Foram realizados ensaios de degradação em reatores em batelada alimentados nas seguintes condições: (1) fenol e sulfato, a diferentes concentrações, com inóculo previamente enriquecido; (2) fenol, sulfato e co-substratos e; (3) fenol, sulfato e extrato de levedura. Todos os ensaios foram realizados em temperatura de 30 graus Celsius, sob agitação de 150 rpm. Foi avaliado o consumo de fenol e sulfato e, produção de metano, em função do tempo, para diferentes concentrações iniciais de fenol e sulfato. Nos ensaios com reatores alimentados com fenol (329,3 mg/l); fenol (307,3 mg/l) e sulfato (160 mg/l); fenol (322.3 mg/l), sulfato (160 mg/l) e lactato (478,16 mg/l); fenol (332,1 mg/l), sulfato (150 mg/l) e etanol (129,76 mg/l), a remoção foi de, respectivamente, 99,8%, 98,2%, 98,8% e 98,8%. Os reatores alimentados com fenol (239,7 mg/l) obtiveram 100% de eficiência na degradação em apenas 11 dias e, os reatores alimentados com fenol (234,3 mg/l) e sulfato (162,5 mg/l) e fenol (256,0 mg/l) e sulfato (500 mg/l) tiveram eficiências de degradação de, respectivamente, 98,8% e 99,3% com 17 dias de operação. Tais eficiências foram obtidas pelo acréscimo de extrato de levedura nos reatores, no início dos ensaios. A caracterização morfológica foi realizada através de microscopia óptica. A diversidade microbiana referente aos Domínios Bacteria e Archaea, além do grupo de bactérias redutoras de sulfato foi avaliada através da técnica de PCR DGGE, onde foram observadas alterações nas populações microbianas, em função das condições nutricionais. Para o Domínio Archaea não foram observadas diferenças nos ensaios realizados. Para o Domínio Bacteria e Grupo das BRS essas diferenças foram, mais facilmente, percebidas com relação ao inóculo e entre os diversos reatores. A alteração na diversidade microbiana pode ter sido decorrente da composição do meio que, nesse caso, foi específico para BRS e a composição do inóculo que continha parte previamente adaptada às BRS. Essas condições adequadas puderam propiciar surgimento e desenvolvimento de populações microbianas capazes de degradar fenol, utilizando sulfato.

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O setor agroindustrial tem se expandido muito nos últimos anos, levando o país a um aumento na geração de resíduos agroindustriais, sendo que a maior parte deles ainda é descartada no meio ambiente, sem tratamento adequado, ou utilizada na alimentação animal, destinos que a priori, não geram ganhos econômicos para a agroindústria além de representarem gargalos logísticos e ambientais na sua disposição. Nesse sentido, o presente trabalho teve como objetivos otimizar o processo de extração de compostos bioativos, avaliar in vitro as atividades antioxidante, por meio da desativação de espécies reativas de oxigênio, e anti-inflamatória, bem como determinar a composição fenólica dos resíduos agroindustriais a saber: película de amendoim (Arachis hypogaea) (cultivares IAC886 e IAC505), pimenta-rosa (Schinus terebinthifolius Raddi) e pimenta-do-reino (Piper Nigrum L). O processo de otimização da extração de compostos antioxidantes foi realizado utilizando dois processos de extração, extração convencional e subcrítica, em delineamento composto central rotacional, utilizando como variáveis a temperatura e tempo e a pressão e temperatura, respectivamente, com os solventes etanol 80%, água e propilenoglicol 80%. Durante o processo de otimização a atividade antioxidante foi avaliada pelo método de sequestro do radical ABTS. Os melhores resultados foram obtidos para a extração convencional com os solventes etanol 80%, água e propilenoglicol 80%. A película de amendoim (IAC505) apresentou as maiores atividades antioxidantes (1.396,67, 580,44 e 859,89 μmol.g-1 em equivalentes de trolox, para os solventes etanol 80%, água e propilenoglicol 80%, respectivamente). A partir dos resultados obtidos para os solventes testados, utilizando a extração convencional, foram feitas outras análises de atividade antioxidante considerando o tempo e temperatura ideal de extração. Foram realizadas análises de avaliação da capacidade de redução de Folin-Ciocalteau e potencial de desativação dos radicais livres sintéticos (DPPH e ABTS) e espécies reativas de oxigênio (radicais peroxila, superóxido e ácido hipocloroso). O solvente de extração que apresentou melhores resultados em todos os ensaios foi o etanol 80%, sendo, portanto o solvente utilizado nas análises subsequentes. A partir da definição do melhor sistema extrator foram realizadas análises da composição fenólica, por meio das técnicas de cromatografia líquida de alta eficiência em modo analítico (HPLC-RP), cromatografia gasosa acoplada com espectrometria de massas (GC-MS), e avaliação in vitro da atividade anti-inflamatória. Foram identificados nos resíduos estudados procianidinas B1 e B2, ácido p-cumárico, miricetina, ácido ferúlico, ácido siríngico, ácido sinápico, epicatequina e catequina. A pimenta-do-reino diminui significativamente os níveis de TNF-α e nitritos, reduzindo assim o processo inflamatório gerado. Os resultados obtidos neste trabalho demonstram que estes resíduos agroindústrias possuem grande potencial biológico, podendo assim ser melhores aproveitados tanto pela indústria de alimentos quanto pela indústria farmacêutica.

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Nos últimos anos tem havido um aumento significativo da procura de frutos vermelhos. Os mirtilos são considerados frutos de boa qualidade, dado o seu elevado teor em compostos fitoquímicos biologicamente ativos, associados a efeitos benéficos para a saúde e bem-estar do Homem. A produção em modo biológico é reconhecida pelo consumidor como um processo que melhora a qualidade do produto. No presente trabalho pretendeu-se avaliar o efeito do modo de produção (biológico versus convencional) de três cultivares de mirtilo (Duke, Bluecrop, Ozarkblue) nas suas propriedades físico-químicas, e em particular na sua composição fenólica e atividade antioxidante. Foi ainda estudado o efeito da temperatura de armazenamento (± 5ºC e ± 15-25ºC) sobre essas propriedades. Para tal, as amostras foram analisadas à colheita e após 7 e 14 dias de armazenamento. A atividade antioxidante medida pelos métodos ABTS e DPPH mostrou que não há diferenças significativas entre as cultivares estudadas, sendo elevada em todos os casos. Os resultados obtidos confirmam, por isso, que o mirtilo é uma importante fonte de compostos fenólicos com elevada atividade antioxidante. Foi ainda verificado existirem algumas diferenças significativas em algumas propriedades em função da variedade (nomeadamente teor em matéria seca, cor ou textura). Também se verificara diferenças significativas em função do modo de produção, o qual influencia em particular a acidez e a doçura, o teor em taninos, a cor e a elasticidade dos frutos. Por fim, a temperatura de armazenamento mostrou ter uma influência significativa apenas no que respeita às propriedades físicas, nomeadamente cor e textura.

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Dissertação para obtenção do grau de Mestre no Instituto Superior de Ciências da Saúde Egas Moniz

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The modern industrial progress has been contaminating water with phenolic compounds. These are toxic and carcinogenic substances and it is essential to reduce its concentration in water to a tolerable one, determined by CONAMA, in order to protect the living organisms. In this context, this work focuses on the treatment and characterization of catalysts derived from the bio-coal, by-product of biomass pyrolysis (avelós and wood dust) as well as its evaluation in the phenol photocatalytic degradation reaction. Assays were carried out in a slurry bed reactor, which enables instantaneous measurements of temperature, pH and dissolved oxygen. The experiments were performed in the following operating conditions: temperature of 50 °C, oxygen flow equals to 410 mL min-1 , volume of reagent solution equals to 3.2 L, 400 W UV lamp, at 1 atm pressure, with a 2 hours run. The parameters evaluated were the pH (3.0, 6.9 and 10.7), initial concentration of commercial phenol (250, 500 and 1000 ppm), catalyst concentration (0, 1, 2, and 3 g L-1 ), nature of the catalyst (activated avelós carbon washed with dichloromethane, CAADCM, and CMADCM, activated dust wood carbon washed with dichloromethane). The results of XRF, XRD and BET confirmed the presence of iron and potassium in satisfactory amounts to the CAADCM catalyst and on a reduced amount to CMADCM catalyst, and also the surface area increase of the materials after a chemical and physical activation. The phenol degradation curves indicate that pH has a significant effect on the phenol conversion, showing better results for lowers pH. The optimum concentration of catalyst is observed equals to 1 g L-1 , and the increase of the initial phenol concentration exerts a negative influence in the reaction execution. It was also observed positive effect of the presence of iron and potassium in the catalyst structure: betters conversions were observed for tests conducted with the catalyst CAADCM compared to CMADCM catalyst under the same conditions. The higher conversion was achieved for the test carried out at acid pH (3.0) with an initial concentration of phenol at 250 ppm catalyst in the presence of CAADCM at 1 g L-1 . The liquid samples taken every 15 minutes were analyzed by liquid chromatography identifying and quantifying hydroquinone, p-benzoquinone, catechol and maleic acid. Finally, a reaction mechanism is proposed, cogitating the phenol is transformed into the homogeneous phase and the others react on the catalyst surface. Applying the model of Langmuir-Hinshelwood along with a mass balance it was obtained a system of differential equations that were solved using the Runge-Kutta 4th order method associated with a optimization routine called SWARM (particle swarm) aiming to minimize the least square objective function for obtaining the kinetic and adsorption parameters. Related to the kinetic rate constant, it was obtained a magnitude of 10-3 for the phenol degradation, 10-4 to 10-2 for forming the acids, 10-6 to 10-9 for the mineralization of quinones (hydroquinone, p-benzoquinone and catechol), 10-3 to 10-2 for the mineralization of acids.

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The use of plants for medicinal purposes is ancient, with widespread application in medicinal drugs. Although plants are promising sources for the discovery of new molecules of pharmacological interest, estimates show that only 17% of them have been studied for their possible use in medicine. Thus, biodiversity of Brazilian flora represents an immense potential for economic use by the pharmaceutical industry. The plant Arrabidaea chica, popularly known as “pariri”, is common in the Amazon region, and it is assigned several medicinal properties. The leaves of this plant are rich in anthocyanins, which are phenolic compounds with high antioxidant power. Antioxidant compounds play a vital role in the prevention of neurological and cardiovascular diseases, cancer and diabetes, among others. Within the anthocyanins found in Arrabidaea chica, stands out Carajurin (6,7-dihydroxy-5,4’- dimethoxy-flavilium), which is the major pigment encountered in this plant. The present work aimed to study on supercritical extraction and conventional extraction (solid-liquid extraction) in leaves of Arrabidaea chica, evaluating the efficiency of the extractive processes, antioxidant activity and quantification of Carajurin contained in the extracts. Supercritical extraction used CO2 as solvent with addition of co-solvent (ethanol/water mixture) and were conducted by the dynamic method in a fixed bed extractor. The trials followed a 24-1 fractional factorial design, the dependent variables were: process yield, concentration of Carajurin and antioxidant activity; and independent variables were: pressure, temperature, concentration of co-solvent (v/v) and concentration of water in the co-solvent mixture (v/v). Yields (mass of dry extract/mass of raw material used) obtained from supercritical extraction ranged from 15.1% to 32%, and the best result was obtained at 250 bar and 40 °C, co-solvent concentration equal to 30% and concentration of water in the co-solvent mixture equal to 50%. Through statistical analysis, it was found that the concentration of co-solvent revealed significant effect on the yield. Yields obtained from conventional extractions were of 8.1% (water) and 5.5% (ethanol). Through HPLC (High-performance liquid chromatography) analysis, Carajurin was quantified in all the extracts and concentration values (Carajurin mass/mass of dry extract) ranged between 1% and 2.21% for supercritical extraction. For conventional extraction, Carajurin was not detected in the aqueous extract, while the ethanol extract showed Carajurin content of 7.04%, and therefore, more selective in Carajurin than the supercritical extraction. Evaluation of antioxidant power (radical 2,2-diphenyl-1-picrylhydrazyl – DPPH – sequestration method) of the supercritical extracts resulted in EC50 values (effective concentration which neutralizes 50% of free radicals) ranged from 38.34 to 86.13 μg/mL, while conventional extraction resulted in EC50 values of 167.34 (water) and 42.58 (ethanol) μg/mL. As for the quantification of total phenolic content (Folin-Ciocalteau analysis) of the supercritical extracts resulted in values ranged from 48.93 and 88.62 mg GAE/g extract (GAE = Gallic Acid Equivalents), while solid-liquid extraction resulted in values of 37.63 (water) and 80.54 (ethanol) mg GAE/g extract. The good antioxidant activity cannot be attributed solely to the presence of Carajurin, but also the existence of other compounds and antioxidants in Arrabidaea chica. By optimizing the experimental design, it was possible to identify the experiment that presented the best result considering the four dependent variables together. This experiment was performed under the following conditions: pressure of 200 bar, temperature of 40 °C, co-solvent concentration equal to 30% and concentration of water in the co-solvent mixture equal to 30%. It is concluded that, within the studied range, it is possible to purchase the optimum result using milder operating conditions, which implies lower costs and greater ease of operation.

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Spondias tuberosa Arruda (Anacardiaceae) is a fruitful tree popularly known as umbuzeiro, tapereba or umbu. It is a native and endemic species from Brazil, widespread in Brazilian Northeast. The species is important in folk medicine of the semi-arid Northeast, where it is mainly used to treat various inflammatory conditions, digestive problems as well as viral and bacterial infections. However, despite the common use in folk medicine, there are scarce pharmacological and phytochemicals studies that afford scientific evidence to its popular use. Therefore, this study aimed to characterize the chemical markers in S. tuberosa leaves extract, obtained by maceration ethanol:water (70:30, [v/v]), and evaluate its anti-inflammatory potential in vivo. The phytochemical profile in TLC analysis suggested the occurence of the flavonoids rutin and isoquercitrin. HPLC analysis enabled us to confirm the presence of flavonoids and also, were detected the phenolic acids, chlorogenic acid and caffeic acid. In addition was developed and validated a HPLC method to evaluate the content of the identified compounds in S. tuberosa leaves extract according to RDC 899/2003 of ANVISA and ICH Guidelines 2005. In order to evaluate the anti-inflammatory potential of S. tuberosa leaves extract, the peritonitis and paw edema models induced by carrageenan were used, administration i.p. in mice. The results highlighted the anti-inflammatory property in vivo at 125, 250 and 500 mg/kg since a decrease in leukocyte influx to the site of inflammation, diameter of the edema and the level of myeloperoxidase were observed when compared to the drug control dexamethasone (2 mg/kg, i.p. route). Taken together, the results pointed out S. tuberosa as a potential species for developing phytotherapic derivatives in according to its popular use. With regard to the characterization markers, chlorogenic acid, caffeic acid, rutin and isoquercitrin were identified and quantified in Spondias tuberosa leaves extract so they could be used in quality control analyses of the raw material and extracts of this species.

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The pericarp of Passiflora edulis var. flavicarpa Degener is now being investigated for medicine purposes. There are no reports about it toxicity. The aim of the present study was investigate the sub chronic toxicity in male rats and reproductive toxicity in pregnant rats and exposed fetuses of an extract obtained by infusion of the pericarp in water (1:3 m/v;100o C, 10 min). The extract composition was evaluated by tube reactions and thin lawyer chromatography (TLC). Adult male rats (n=8) were treated with 300 mg/kg of the extract, by gavage, during 30 days and pregnant rats (n=7) from gestation day 0 to day 20. Control received tap water (1 mL). Water and food intakes and body weight gain were recorded. At day 29 of treatment the sexual behavior of the males was analyzed and then half of males from each group received cyclophosphamide (50 mg/kg, i.p.) to (anti)genotoxic assessment in bone marrow. At day 30, males were anesthesized for parameters collection. At day 20 of gestation, the dams were anesthesized for reproductive performance evaluation. The fetal analysis was conducted by visceral and skeletal. Phytochemical analysis revealed the presence of flavonoids, unspecific alkaloids, phenols and triterpenic compounds. Statistical analysis revealed absence of significant differences between experimental and control. This study suggest that the aqueous extract obtained from pericarp of P. edulis var. flavicarpa Degener was not able to promote toxic effects in rats. Cytotoxicity was evaluated with the PCE/NCE ratio (NCE=normochromatic erythrocytes). Statistical analysis (mean ± SEM) revealed absence of changes in the frequency of MNPCE (negative control: 3.26±0.42; positive control: 11.72±1.02; negative experimental: 4.02±0.13; positive experimental: 10.47±0.87) or cytotoxicity (negative control: 0.37±0.08; positive control: 0.23±0.05; negative experimental: 0.37±0.07; positive experimental: 0.23±0.02). This study suggests that the extracts showed no (anti)genotoxic and no cytotoxic activities under the experimental conditions.

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The uncontrolled disposal of wastewaters containing phenolic compounds by the industry has caused irreversible damage to the environment. Because of this, it is now mandatory to develop new methods to treat these effluents before they are disposed of. One of the most promising and low cost approaches is the degradation of phenolic compounds via photocatalysis. This work, in particular, has as the main goal, the customization of a bench scale photoreactor and the preparation of catalysts via utilization of char originated from the fast pyrolysis of sewage sludge. The experiments were carried out at constant temperature (50°C) under oxygen (410, 515, 650 and 750 ml min-1). The reaction took place in the liquid phase (3.4 liters), where the catalyst concentration was 1g L-1 and the initial concentration of phenol was 500 mg L-1 and the reaction time was set to 3 hours. A 400 W lamp was adapted to the reactor. The flow of oxygen was optimized to 650 ml min-1. The pH of the liquid and the nature of the catalyst (acidified and calcined palygorskite, palygorskite impregnated with 3.8% Fe and the pyrolysis char) were investigated. The catalytic materials were characterized by XRD, XRF, and BET. In the process of photocatalytic degradation of phenol, the results showed that the pH has a significant influence on the phenol conversion, with best results for pH equal to 5.5. The phenol conversion ranged from 51.78% for the char sewage sludge to 58.02% (for palygorskite acidified calcined). Liquid samples analyzed by liquid chromatography and the following compounds were identified: hydroquinone, catechol and maleic acid. A mechanism of the reaction was proposed, whereas the phenol is transformed into the homogeneous phase and the others react on the catalyst surface. For the latter, the Langmuir-Hinshelwood model was applied, whose mass balances led to a system of differential equations and these were solved using numerical methods in order to get estimates for the kinetic and adsorption parameters. The model was adjusted satisfactorily to the experimental results. From the proposed mechanism and the operating conditions used in this study, the most favored step, regardless of the catalyst, was the acid group (originated from quinone compounds), being transformed into CO2 and water, whose rate constant k4 presented value of 0.578 mol L-1 min-1 for acidified calcined palygorskite, 0.472 mol L-1 min-1 for Fe2O3/palygorskite and 1.276 mol L-1 min-1 for the sludge to char, the latter being the best catalyst for mineralization of acid to CO2 and water. The quinones were adsorbed to the acidic sites of the calcined palygorskite and Fe2O3/palygorskite whose adsorption constants were similar (~ 4.45 L mol-1) and higher than that of the sewage sludge char (3.77 L mol-1).

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The uncontrolled disposal of wastewaters containing phenolic compounds by the industry has caused irreversible damage to the environment. Because of this, it is now mandatory to develop new methods to treat these effluents before they are disposed of. One of the most promising and low cost approaches is the degradation of phenolic compounds via photocatalysis. This work, in particular, has as the main goal, the customization of a bench scale photoreactor and the preparation of catalysts via utilization of char originated from the fast pyrolysis of sewage sludge. The experiments were carried out at constant temperature (50°C) under oxygen (410, 515, 650 and 750 ml min-1). The reaction took place in the liquid phase (3.4 liters), where the catalyst concentration was 1g L-1 and the initial concentration of phenol was 500 mg L-1 and the reaction time was set to 3 hours. A 400 W lamp was adapted to the reactor. The flow of oxygen was optimized to 650 ml min-1. The pH of the liquid and the nature of the catalyst (acidified and calcined palygorskite, palygorskite impregnated with 3.8% Fe and the pyrolysis char) were investigated. The catalytic materials were characterized by XRD, XRF, and BET. In the process of photocatalytic degradation of phenol, the results showed that the pH has a significant influence on the phenol conversion, with best results for pH equal to 5.5. The phenol conversion ranged from 51.78% for the char sewage sludge to 58.02% (for palygorskite acidified calcined). Liquid samples analyzed by liquid chromatography and the following compounds were identified: hydroquinone, catechol and maleic acid. A mechanism of the reaction was proposed, whereas the phenol is transformed into the homogeneous phase and the others react on the catalyst surface. For the latter, the Langmuir-Hinshelwood model was applied, whose mass balances led to a system of differential equations and these were solved using numerical methods in order to get estimates for the kinetic and adsorption parameters. The model was adjusted satisfactorily to the experimental results. From the proposed mechanism and the operating conditions used in this study, the most favored step, regardless of the catalyst, was the acid group (originated from quinone compounds), being transformed into CO2 and water, whose rate constant k4 presented value of 0.578 mol L-1 min-1 for acidified calcined palygorskite, 0.472 mol L-1 min-1 for Fe2O3/palygorskite and 1.276 mol L-1 min-1 for the sludge to char, the latter being the best catalyst for mineralization of acid to CO2 and water. The quinones were adsorbed to the acidic sites of the calcined palygorskite and Fe2O3/palygorskite whose adsorption constants were similar (~ 4.45 L mol-1) and higher than that of the sewage sludge char (3.77 L mol-1).

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Ulcerative colitis is a chronic disease characterized by inflammation in the intestinal mucosa, in most cases affects the colon and rectum. The therapeutic drugs are used as aminosalicylates and glucocorticosteroids, but due to the low response and the various side effects caused by them, reveals the need to search for new sources of useful compounds in the treatment of this disease.The species Anacardium occidentale popularly known as cashew, has been used for centuries in folk medicine in the healing aid of skin and mucosa lesions.Recent studies show its expressive antiulcerogenic effect, what we instigated to assess the effect of the extract of A. occidentaleleaves in rats with acute ulcerative colitis, therefore, 42 rats were used male Wistar, divided into 06 groups, and Negative Control (C) Positive Control (C +), treated with Sulfasalazine (Sz500) and treated with Extract A. occidentale at doses of 50 (Ao50), 100 (Ao100) and 200 mg / kg (Ao200).All groups were submitted to experimental colitis Ulcerative except C-, moreover, C- and C + received saline via gavage for 7 consecutive days while the other groups received their respective treatments.Euthanasia of animals took place on the 8th day in which it was collected intestinal colon sample for later analysis macroscopic, histopathological, morphometric and biochemistry, as well as complementary collection of blood and liver tissue. The extract is rich in saponins and phenolic compounds such as flavonoids (quercetin and kaempferol) and tannins.When the Sz500 groups and 100 showed significant protection to damage to lipids and proteins, among the groups subjected to experimental ulcerative colitis, the animals Ao100 group obtained the lowest score in all parameters analyzed.Treatment with 100 mg / kg of A. occidentale extract seems to have a combination of antiinflammatory, antioxidant, bactericidal and anabolic promoted by the bioactive compounds present in the extract.However, it is necessary to investigate harder treating dose of 100mg / kg to higher doses compared to elucidate more properly the best therapeutic dosage ulcerative colitis.

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Introduction: Licania rigida Benth and Turnera ulmifolia Linn. var. elegans are species of semi-arid regional plants used in the treatment of various diseases. Objectives: The purpose of this study was chemically characterize the extracts and fractions and investigate the antimicrobial and antioxidant potential. Methods: For chemical analysis, were performed spectrophotometric quantification of the total phenolic and characterization of the extracts by chromatographic analysis. Evaluation of antioxidant activity was done by determining the radical scavenging capacity DPPH •. Antimicrobial activity was evaluated by agar diffusion, broth microdilutionand time-kill assays. Results: The extracts and fractions L. rigid and T. ulmifolia showed a high phenolic content, the presence of flavonoids, which were determined as chemical markers. It was observed that the extracts of both species performed as sequestering agents in the trial of antioxidant activity in vitro. The L. rigida extract was the only active front strains of S. aureus 33591 (methicillin-resistant), S. aureus 29213, S. epidermidis 12228, and also against the yeast, Candida albicans, Candida dubliniensis, Candida tropicalis, Candida parapsilosis, Candida rugosa, Candida krusei eTrichosporon asahii. Conclusions: Based on these results it is possibly affirm the antioxidant and antimicrobial activity of L. rigida and attributed the presence of polyphenolic flavonoid like responsible.

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The Banisteriopsis genus is widespread in traditional medicine. This work aims to contribute with information about the chemical composition and on the evaluation of the biological activity of the essential oil, the ethanol extract of the leaves and partitions of the Banisteriopsis laevifolia. The phytochemical screeningtest of ethanol extract and partitions of leaves indicated the presence of flavonoids, terpenoids, saponins, phenols and steroids compounds. Nitrogenous compounds, characteristic of some species of this family, were not detected. Flavonoids were the predominant metabolite, with the highest concentrations on the partitions ethyl acetate and n-butanol. The antibacterial activity, antifungal and cytotoxicity of the essetial oil, ethanol extract and partitions were assyed by microdilution broth method (MBM), where the minimum inhibitory concentrations (MIC) were calculated. The ethanol extract and partitions did not inhibit growth against to Gram positive bacteria tested, with MIC less than 400 mg L-1. For the Gram negative bacteria tested, the hexane and hydroethanol partitios were more effective against F. nucleatum bacteria (MIC 100 ug mL-1). The ethanol extract showed antifungal activity with MIC of 31.2 mg L-1. Ethyl acetate and n-butanol partitions showed MIC 187.5 mg L-1 and 93.7 mg L-1, respectively, arousing interest for isolation studies. The antioxidant activity was evaluated by the DPPH free radical method. The ethanolic extract, ethyl acetate and n-butanol partitions were active, since they showed EC50 values (4.53 ug mL-1, 4.07 and 8.39 ug mL-1, respectively), values equivalent to the BHT (7.3 mg L-1). The analysis by HPLC-MS/MS of the most active fractions (ethyl acetate and n-butanol) identified phenolic compounds (flavonols and phenolic acids) which exert recognized biological activity. The GC-MS analysis of the essential oils from leaves collected in two periods studied (dry and wet), showed a small variation in the number of compounds. The major classes identified for the oil collected in the dry period were aliphatic alcohols (23,4%), terpenoids (18.7%), sterols (10.4%) and long-chain alkanes (9.2%) compounds. Terpenoids (26.8%) were the major class for the rain season. The major compounds (3Z) -hexenol, phytol and untriacontano are present in the two seasons but in different amounts (19.4%, 9.8% and 7.5% during the dry season, and 17.0 %, 14.9% and 15.3% in the rainy season, respectively). The essential oil from rainy season was not effective against to the oral bacteria Gram positive and Gram negative tested. However, showed significant antifungal activity with MIC 1000 mg L-1 against Candidas. Thus, the promising results with respect to biological assays of ethanolic extract and partitions from B. laevifolia contributed to the chemical and biological knowledge of the species B. laevifolia.