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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
111

Enzymové a metabolické přeměny silybinu a vybraných flavonoidů / Enzymatic and Metabolic Transformation of Silybin and its Congeners

Purchartová, Kateřina January 2016 (has links)
Natural flavonoids and flavonolignans feature beneficial properties for living organisms such as antioxidant and hepatoprotective effects, anticancer, chemoprotective, dermatoprotective and hypocholesterolemic activities. Their metabolism in mammals is complex, the exact structure of their metabolites still remains partly unclear and the standards are usually not commercially available. Hence, this project focused on the preparation of potential and defined biotransformation Phase II sulfated metabolites of silymarin flavonolignans: silybin, 2,3-dehydrosilybin, isosilybin, silychristin, silydianin and flavonoids quercetin, taxifolin, rutin and isoquercitrin. Pure sulfated derivatives were prepared using aryl sulfotransferase from Desulfitobacterium hafniense and aryl sulfotransferase from rat liver. Using heterologously expressed PAPS (3'-phosphoadenosine-5'-phosophosulfate) - independent arylsulfotransferase from Desulfitobacterium hafniense and cheap p-nitrophenyl sulfate as sulfate donor, sulfated flavonolignans and flavonoids were obtained in high yields. Silymarin flavonolignans afforded exclusively monosulfates at the position C-20 (C-19 in the case of silychristin), except 2,3-dehydrosilybin that yielded also the 7,20-O-disulfated derivative. Isoquercitrin and rutin were selectively sulfated...
112

Étude cinétique et modélisation des effets des traitements thermiques et de l’environnement physico-chimique sur la dégradation et l’activité antioxydante des flavonoïdes / Kinetic study and modeling of the effects of heat treatments and physical-chemical environment on the antioxidant activity of flavonoids and their derivatives

Chaaban, Hind 20 June 2017 (has links)
Les objectifs de cette thèse sont d’une part d'étudier les effets d’un traitement thermique et de l’environnement physico-chimique sur la stabilité de 6 flavonoïdes de structure différente et sur l'évolution de leur activité anti-oxydante. Les conditions du traitement thermique ont été les suivantes : (i) chauffage dans des conditions isothermes durant 2h pour des températures allant de 30 à 130°C et (ii) chauffage dans des conditions non isothermes par microcalorimétrie (de 30 à 130°C, 4°C/ heure). Les flavonoïdes ont été solubilisés dans de l’eau. Nous avons constaté que les flavonoïdes glycosylés sont plus résistants que les flavonoïdes aglycones. Les énergies d'activation de dégradation calculées dépendent aussi de la structure du flavonoïde. Pour se dégrader, les flavonoïdes glycosylés ont besoin d’une énergie élevée par rapport à la forme aglycone. L’exposition à la lumière a été réalisée durant 15 jours avec et sans oxygène, le témoin de l’expérience étant un stockage à l’obscurité avec et sans oxygène. La dégradation des flavonoïdes est influencée par la présence de lumière et par la quantité d'oxygène. Les molécules ont une sensibilité différente en fonction de leur structure, le classement suivant est obtenu d’après : naringine, ériodictyol puis rutine, lutéoline, lutéoline 7-O-glucoside et enfin le mesquitol. En effet, la présence d'un groupe hydroxyle en position 3 et une double liaison C2-C3 diminue la stabilité des flavonoïdes. En outre, il a été observé que, malgré la dégradation totale de certains flavonoïdes par le traitement thermique et l’environnement physico-chimique, les solutions traitées conservent une activité anti-oxydante / The objectives of this thesis are to study the effects of a heat treatment and the physicochemical environment on the stability of 6 flavonoids of different structure and on the evolution of their antioxidant activity. The heat treatment conditions were as follows: (i) heating under isothermal conditions for 2 h at temperatures ranging from 30 to 130 ° C and (ii) heating under non-isothermal conditions by microcalorimetry (30 to 130 ° C, 4 ° C / hour). The flavonoids were solubilized in water. We found that the glycosylated flavonoids are more resistant than the aglyconic flavonoids. The calculated degradation activation energies also depend on the structure of the flavonoid. To degrade, glycosylated flavonoids require high energy relative to the aglycone form. Exposure to light was carried out for 15 days with and without oxygen, the experimental control being a dark storage with and without oxygen. The degradation of flavonoids is influenced by the presence of light and by the amount of oxygen. The molecules have a different sensitivity according to their structure, the following classification is obtained according to: naringine, ériodictyol then rutin, luteolin, luteolin 7-O-glucoside and finally the mesquitol. Indeed, the presence of a hydroxyl group at position 3 and a C2-C3 double bond reduces the stability of the flavonoids. Furthermore, it has been observed that, despite the total degradation of certain flavonoids by the heat treatment and the physical-chemical environment, the treated solutions retain an antioxidant activity
113

Estudos químico e biológico de espécies de hypericum das seções Brathys e Trigynobrathys / Phytochemical and biological study of the Hypericum species of the Brathys and Trigynobrathys sections

Barros, Francisco Maikon Corrêa de January 2013 (has links)
O gênero Hypericum (Guttiferae = Clusiaceae) compreende 494 espécies acomodadas em 36 seções taxonômicas. Os representantes americanos pertencem, sobretudo, às seções Brathys e Trigynobrathys, as duas maiores com 87 e 52 espécies, respectivamente. Popularmente, estas plantas são utilizadas como antissépticos, diuréticos, digestivos e agentes de cicatrização. Quimicamente, apresentam tendência em acumular floroglucinóis diméricos, além de benzofenonas, benzopiranos, flavonoides e ácidos fenólicos, metabólitos cuja atividade antidepressiva, antinociceptiva, antimicrobiana, antiproliferativa e antioxidante são descritas. Considerando o potencial terapêutico, este trabalho objetivou a determinação dos principais compostos fenólicos presente nas flores de espécies Hypericum nativas do Sul do Brasil (H. campestre, H. caprifoliatum, H. carinatum, H. connatum, H. linoides, H. myrianthum, H. polyanthemum e H. salvadorense) e dos Páramos peruanos (H. andinum e H. laricifolium); a extração e análise dos compostos fenólicos de H. carinatum obtidos com CO2 supercrítico e a investigação da atividade antifúngica e antiquimiotática dos extratos lipofílicos de H. caprifoliatum, H. carinatum, H. linoides, H. myrianthum e H. polyanthemum. Para os experimentos, foram coletadas (2008 - 2010) as partes aéreas das plantas em floração. Todas as coletas foram autorizadas pelos órgãos de proteção ambiental. Os métodos extrativos incluem maceração estática, ultrassom e CO2 supercrítico (temperatura = 40, 50 ou 60ºC; pressão = 90, 120, 150 ou 200 bar). As análises por CLAE foram realizadas em coluna de fase reversa (C18), sistemas isocráticos compostos por acetonitrila, água e ácido trifluroacético e detecção ultravioleta (220, 270 ou 254 nm); Os picos foram identificados pela comparação dos tempos de retenção/co-injeção com padrões e quantificados pela curva de calibração dos compostos. Os ensaios antifúngico e antiquimiotático foram realizados pelo método de microdiluição em caldo e inibição da migração de neutrófilos, respectivamente. O floroglucinol dimérico uliginosina B (0,008 – 0,188%) e o flavonoide hiperosídeo (0,057 – 5,987%) foram os principais metabólitos detectados nas flores das espécies investigadas. Hypericum caprifoliatum e H. andinum apresentaram o maior rendimento destes compostos, respectivamente. Sete espécies apresentaram japonicina A em concentrações de 0,003 a 0,087% (H. myrianthum). O rendimento de hiperbrasilol B variou de 0,006% em H. laricifolium a 0,011% em H. caprifoliatum. Os benzopiranos (HP1 = 0,200%, HP2 = 0,225% e HP3 = 0,327%) e as benzofenonas (carifenona A = 0,309% e carifenona B = 0,062%) ocorreram exclusivamente em H. polyanthemum e H. carinatum. As máximas quantidades de ácido clorogênico, isoquercitrina, quercitrina e guaijaverina foram observadas, respectivamente, em H. campestre (1,458%), H. andinum (1,161%), H. carinatum (0,231%) e H. laricifolium (0,404%). Tais resultados fornecem suporte adicional para o significado quimiotaxonômico dos derivados diméricos de floroglucinol. Temperatura (40°C = 3,04%, 50°C = 2,21% e 60°C = 1,05%) e pressão (90 bar = 0,95%, 150 bar = 0,97% e 200 bar = 1,89%) afetaram de modo distinto o rendimento do extrato supercrítico de H. carinatum. Apesar do menor rendimento em comparação ao extrato n-hexano (6,09%), a extração com CO2 supercrítico provou ser mais seletiva que a maceração. Nas condições ideais (40°C, 90 bar e 180 minutos), a máxima recuperação de uliginosina B, carifenona A e carifenona B foi, respectivamente, 162,83, 376,33 e 48,79%. O modelo matemático empregado para simular o processo de extração foi apropriadamente correlacionado aos dados experimentais. Considerando as atividades biológicas, todas as espécies investigadas apresentaram um amplo espectro de ação antifúngica, assim como reduziram a migração dos neutrófilos. Os extratos de H. carinatum, H. linoides e H. myrianthum apresentaram os mais baixos valores de concentração inibitória mínima contra Cryptococcus neoformans (CIM £ 15,6 μg/mL), Rhodotorula mucilaginosa (CIM £ 62,5 μg/mL), Candida glabrata e C. tropicalis (CIM = 1,9-250 μg/mL). Para estas plantas, o efeito antiquimiotático variou entre 60 - 100% nas concentrações de 0,31 a 10 μg/mL. Os extratos mais ativos apresentaram elevada concentração de uliginosina B, japonicina A e hiperbrasilol B. Assim, as espécies de Hypericum nativas do sul do Brasil apresentam potencial como fonte de novos antifúngicos e anti-inflamatórios. / The genus Hypericum (Guttiferae = Clusiaceae) comprises 494 species placed in 36 taxonomic sections. The representatives of Central and South America belong primarily to sections Brathys and Trigynobrathys, the two largest sections with 87 and 52 species, respectively. In traditional medicine, these plants are used as antiseptic, diuretic, digestive and as healing agents. Such species have a strong tendency to accumulate dimeric phloroglucinol, besides benzophenones, benzopyrans, flavonoids and phenolic acids, metabolites whose antidepressant, antinociceptive, antimicrobial, antiproliferative and antioxidant activities are described. In view of the therapeutic potential, this work aimed to determine the main phenolic compounds present in flowers of Hypericum species native to southern Brazil (H. campestre, H. caprifoliatum, H. carinatum, H. connatum, H. linoides, H. myrianthum, H. polyanthemum and H. salvadorense) and to Peruvian Páramos (H. andinum and H. laricifolium); the supercritical CO2 extraction and analysis of the phenolic compounds of H. carinatum; the antifungal and antichemotactic activities of the lipophilic extracts from H. caprifoliatum, H. carinatum, H. linoides, H. myrianthum and H. polyanthemum. For the experiments, aerial parts in blossom were harvested (2008 - 2010). All collections were authorized by competent agencies of environmental protection. The extraction methods employed were static maceration, ultrasonic bath or supercritical CO2 (temperature = 40, 50 or 60ºC; pressure = 90, 120, 150 or 200 bar). HPLC analyses were carried out in reverse phase column (C18), isocratic system composed of acetonitrile, water and trifluoroacetic acid, and ultraviolet detection (220, 270 or 254 nm). Peaks were identified by comparison of retention times / co-injection with standards and quantified by calibration curve of the compounds. Antifungal and antichemotactic tests were performed using the broth microdilution assay and neutrophils migration inhibition method. The dimeric phloroglucinol uliginosin B (0.008 - 0.188%) and the flavonoid hyperoside (0.057 - 5.987%) were the main metabolite detected in flowers of the investigated species. Hypericum caprifoliatum and H. andinum displayed higher yields of these compounds, respectively. Japonicin A was found in seven species studied at concentrations that varied from 0.003 to 0.087% (H. myrianthum). The yield of hyperbrasilol B ranged from 0.006% in H. laricifolium to 0.011% in H. caprifoliatum. The benzopyrans (HP1 = 0.200%, HP2 = 0.225% and HP3 = 0.327%) and benzophenones (cariphenone A = 0.309% and cariphenone B = 0.062%) occurred exclusively in H. polyanthemum and H. carinatum. Maximum amounts of chlorogenic acid, isoquercitrin, quercitrin and guaijaverin were observed, respectively, in H. campestre (1.458%), H. andinum (1.161%), H. carinatum (0.231%) and H. laricifolium (0.404%). Such results provide a further support for the chemotaxonomic significance of the dimeric phloroglucinols. Temperature (40°C = 3.04%, 50°C = 2.21% and 60°C = 1.05%) and pressure (90 bar = 0.95%, 150 bar = 0.97% and 200 bar = 1.89%) critical did affect differently the yield of supercritical extract of H. carinatum. Despite lower yield in comparison to n-hexane extract (6.09%), supercritical CO2 extraction proved to be more selective than maceration. In optimal conditions (40°C, 90 bar and 180 minutes), the maximum amount of uliginosin B, cariphenone A and cariphenone B was, respectively, 162.83, 376.33 and 48.79%. Lastly, the mathematical model used in the process of supercritical extraction was properly correlated to the experimental data. Regarding the biological activities, all investigated species exhibited a broad spectrum of antifungal action as well as reduced neutrophils migration. Hypericum carinatum, H. linoides and H. myrianthum extracts presented the lowest value of minimum inhibitory concentration against Cryptococcus neoformans (MIC ≤ 15.6 μg/mL), Rhodotorula mucilaginosa (MIC ≤ 62.5 μg/mL), Candida glabrata and C. tropicalis (MIC range = 1.9 - 250 μg/mL). For these plants, the antichemotactic effect varied from 60-100% at concentrations of 0.31 to 10 μg/mL. The most active extracts were that presented high amounts of uliginosin B, japonicin A and hyperbrasilol B. Thus, the Hypericum species native to Southern Brazil show potential as source of new anti-infectives and anti-inflammatory drugs.
114

Selected Point Mutations of a Flavonoid 3-O-Glucosyltransferase from Citrus paradisi (Grapefruit) and Effect on Substrate and Regiospecificity

Adepoju, Olusegun A., Shiva, Devaiah K., McIntosh, Cecelia A. 04 August 2013 (has links)
Flavonoids are secondary metabolites that are important in plant defense, protection, and human health. Most naturally-occurring flavonoids are found in glucosylated form. Glucosyltransferases (GTs) are enzymes that catalyze the transfer of glucose from a high energy sugar donor to an acceptor molecule. At this time, it is not possible to accurately predict putative GT activity from sequence alone; biochemical characterization is critical. A flavonol-specific 3-O-GT enzyme has been identified and cloned from the leaf tissues of grapefruit. The enzyme shows rigid substrate specificity and regiospecificity. F3GTs from grape and grapefruit were modeled against F7GTs from Crocus sativus and Scrutellaria biacalensis, and several non-conservative amino acid differences were identified that may impact regioselectivity. This research is designed to test the hypothesis that specific amino acid residues impart the regiospecificity of the grapefruit enzyme. Site-directed mutagenesis was performed on three potentially key amino acid residues within the grapefruit F3-GT that were identified through homology modeling. Enzyme activity of the mutant F3-GT proteins will be analyzed for a possible change in glucosylation pattern. Other flavonoid classes will also be tested with the mutant enzymes to test for change in substrate specificity.
115

Selected Point Mutation of a Flavonoid 3-0-Glucosyltransferase from Citrus paradisi (Grapefruit) and its Effect on Substrate and Regiospecificity

Adepoju, Olusegun A., Shiva, Devaiah K., McIntosh, Cecelia A. 04 April 2013 (has links)
Flavonoids are secondary metabolites that are important in plant defense, protection, and human health. Most naturally-occurring flavonoids are found in glucosylated form. Glucosyltransferases (GTs) are enzymes that catalyze the transfer of glucose from a high energy sugar donor to an acceptor molecule. At this time, it is not possible to accurately predict putative GT activity from sequence alone; biochemical characterization is critical. A flavonol-specific 3-O-GT enzyme has been identified and cloned from the leaf tissues of grapefruit. The enzyme shows rigid substrate specificity as well as regiospecificity. Several F3GT's characterized from other plants also had the ability to glucosylate anthocyanidins, however the grapefruit F3GT did not. This research is designed to test the hypothesis that specific amino acid residues impart the substrate specificity and regiospecificity of the grapefruit enzyme. Site-directed mutagenesis was performed on three potentially key amino acid residues within the grapefruit F3-GT that were identified through homology modelling. Enzyme activity of the mutant F3-GT proteins will be tested with flavonols for a possible change in glucosylation pattern. Other flavonoid classes will also be tested with the mutant F3-GT enzyme to test for change in substrate specificity. The result from this study will add to our knowledge of GTs.
116

Avaliação Nutricional das folhas de Moringa oleífera para aves / Nutritional Assessment of Moringa oleifera leaves for birds

Marinho, Jéssica Berly Moreira 25 May 2016 (has links)
Submitted by Socorro Pontes (socorrop@ufersa.edu.br) on 2017-03-17T15:14:09Z No. of bitstreams: 1 JéssicaBMM_DISSERT.pdf: 581155 bytes, checksum: 7e403d68146a4eae342ccc4a752f27c5 (MD5) / Made available in DSpace on 2017-03-17T15:14:09Z (GMT). No. of bitstreams: 1 JéssicaBMM_DISSERT.pdf: 581155 bytes, checksum: 7e403d68146a4eae342ccc4a752f27c5 (MD5) Previous issue date: 2016-05-25 / Conselho Nacional de Desenvolvimento Científico e Tecnológico / Moringa oleifera leaves are considered a promising food for the Northeast because of its nutritional profile and its ability to be keeping green during periods of drought. The research objective was to evaluate the physical and chemical composition and digestibility and energy value of sheets of dried moringa for birds. The chemical analyzes were carried out for crude protein, dry matter, ether extract, neutral detergent fiber and acid detergent fiber, ash and gross energy by the conventional method and the next spectrometry method of infrared. In the measurement of chlorophyll and the main bioactive compounds such as anthocyanins, total carotenoids, flavonoids yellow, total extractable polyphenols and vitamin C through the spectrometric method. The results of the composition of the dried leaves of the Moringa showed that it has good crude protein (30.93%) for conventional analysis and analysis in NIRS (31.64%) anthocyanins (1.02 mg / 100g), carotenoids total (1.48 mg / kg), chlorophyll (120.62 mg / kg), yellow flavonoids (25.76 mg / 100g), polyphenols (105.15 mg / 100g), especially the amount of vitamin C (485.71 mg / 100g). In the digestibility trial, 20 adult birds were housed individually in cages adapted for excreta collection, with five treatments (0, 5, 10, 15 and 20% inclusion of moringa leaves), distributed in a completely randomized design. For apparent digestibility of diets with increasing levels of inclusion of dehydrated leaves of Moringa oleifera was observed a decreasing linear effect for mineral matter (MM)), y = 27.3120 - 0,4934x, (R2 = 0.65) , ether extract (EE), y = 87.3124 - 0,9394x, (R2 = 0.72); neutral detergent fiber (NDF), y = 29.6686 - 0,2957x, (R2 = 0.61); acid detergent fiber (ADF), y = 20.2322 - 0,1688x, (R2 = 0.68); for the metabolization coefficient of gross energy (GE), y = 72.4564 - 0,4285x, (R2 = 0.77) and apparent metabolizable energy of feed (EMA) y = 3783.96 - 15,52x ( R2 = 0.29). With exeção of dry matter (DM) and crude protein (CP), that no significant effects. The value of apparent metabolizable energy of moringa leaves for adult birds was 2.155,81kcal / kg, a value obtained by Matterson technique. Also the coefficient of energy metabolism (CME) with 47.44% for moringa leaf was observed / As folhas de Moringa oleífera são consideradas um alimento promissor para região nordeste, devido ao seu perfil nutricional e sua capacidade de ser manter verde durante os períodos de estiagem. Diante disso, objetivou-se avaliar a composição físicoquímica e a digestibilidade e o valor energético das folhas de moringa desidratadas para aves. As análises bromatológicas foram realizadas quanto aos teores de proteína bruta, matéria seca, extrato etéreo, fibra em detergente neutro e fibra em detergente ácido, cinzas e energia bruta pelo método convencional e pelo método de espectrometria próxima de infravermelho. Além da quantificação de clorofila a e principais compostos bioativos como: antocianinas, caratenoides totais, flavonoides amarelos, polifenóis extraíveis totais e vitamina C, através do método de espectrometria. Os resultados da composição das folhas desidratadas da moringa mostraram que a mesma apresenta bons teores de proteína bruta (30,93%) para análises convencionais e para análises no NIRS (31,64%) antocianinas (1,02 mg/100g), carotenoides totais (1,48 mg/kg), clorofila a (120,62 mg/kg), flavonoides amarelos (25,76 mg/100g), polifenóis (105,15 mg/100g) , destacando-se a quantidade de vitamina C (485,71 mg/100g). No ensaio de digestibilidade, 20 aves adultas foram alojadas individualmente em gaiolas metálicas adaptadas para coleta total de excretas, com cinco tratamentos (0, 5, 10, 15 e 20% de inclusão das folhas de moringa), distribuídas em delineamento inteiramente casualizado. Para coeficientes de digestibilidade aparente das rações com níveis crescentes de inclusão de folhas desidratadas de Moringa oleífera, foi observado um efeito linear decrescente para matéria mineral (MM) ), y= 27,3120 – 0,4934x, (R2 = 0,65), extrato etéreo (EE), y= 87,3124 – 0,9394x, (R2 = 0,72); fibra em detergente neutro (FDN), y= 29,6686 - 0,2957x, (R2 = 0,61); fibra em detergente ácido (FDA), y= 20,2322 – 0,1688x, (R2 = 0,68); para o coeficiente de metabolização de energia bruta (EB), y= 72,4564 – 0,4285x, (R2 = 0,77) e para energia metabolizável aparente das rações (EMA) y= 3783,96 – 15,52x, (R2 = 0,29). Com exeção da matéria seca (MS) e da proteína bruta (PB),que não observados efeitos significativos. O valor de energia metabolizável aparente das folhas de moringa para aves adultas foi de 2.155,81kcal/kg, valor este obtido através da técnica de Matterson. Também foi observado o coeficiente de metabolização de energia (CME) com 47,44 % para folha de moringa / 2017-03-16
117

Estudos químico e biológico de espécies de hypericum das seções Brathys e Trigynobrathys / Phytochemical and biological study of the Hypericum species of the Brathys and Trigynobrathys sections

Barros, Francisco Maikon Corrêa de January 2013 (has links)
O gênero Hypericum (Guttiferae = Clusiaceae) compreende 494 espécies acomodadas em 36 seções taxonômicas. Os representantes americanos pertencem, sobretudo, às seções Brathys e Trigynobrathys, as duas maiores com 87 e 52 espécies, respectivamente. Popularmente, estas plantas são utilizadas como antissépticos, diuréticos, digestivos e agentes de cicatrização. Quimicamente, apresentam tendência em acumular floroglucinóis diméricos, além de benzofenonas, benzopiranos, flavonoides e ácidos fenólicos, metabólitos cuja atividade antidepressiva, antinociceptiva, antimicrobiana, antiproliferativa e antioxidante são descritas. Considerando o potencial terapêutico, este trabalho objetivou a determinação dos principais compostos fenólicos presente nas flores de espécies Hypericum nativas do Sul do Brasil (H. campestre, H. caprifoliatum, H. carinatum, H. connatum, H. linoides, H. myrianthum, H. polyanthemum e H. salvadorense) e dos Páramos peruanos (H. andinum e H. laricifolium); a extração e análise dos compostos fenólicos de H. carinatum obtidos com CO2 supercrítico e a investigação da atividade antifúngica e antiquimiotática dos extratos lipofílicos de H. caprifoliatum, H. carinatum, H. linoides, H. myrianthum e H. polyanthemum. Para os experimentos, foram coletadas (2008 - 2010) as partes aéreas das plantas em floração. Todas as coletas foram autorizadas pelos órgãos de proteção ambiental. Os métodos extrativos incluem maceração estática, ultrassom e CO2 supercrítico (temperatura = 40, 50 ou 60ºC; pressão = 90, 120, 150 ou 200 bar). As análises por CLAE foram realizadas em coluna de fase reversa (C18), sistemas isocráticos compostos por acetonitrila, água e ácido trifluroacético e detecção ultravioleta (220, 270 ou 254 nm); Os picos foram identificados pela comparação dos tempos de retenção/co-injeção com padrões e quantificados pela curva de calibração dos compostos. Os ensaios antifúngico e antiquimiotático foram realizados pelo método de microdiluição em caldo e inibição da migração de neutrófilos, respectivamente. O floroglucinol dimérico uliginosina B (0,008 – 0,188%) e o flavonoide hiperosídeo (0,057 – 5,987%) foram os principais metabólitos detectados nas flores das espécies investigadas. Hypericum caprifoliatum e H. andinum apresentaram o maior rendimento destes compostos, respectivamente. Sete espécies apresentaram japonicina A em concentrações de 0,003 a 0,087% (H. myrianthum). O rendimento de hiperbrasilol B variou de 0,006% em H. laricifolium a 0,011% em H. caprifoliatum. Os benzopiranos (HP1 = 0,200%, HP2 = 0,225% e HP3 = 0,327%) e as benzofenonas (carifenona A = 0,309% e carifenona B = 0,062%) ocorreram exclusivamente em H. polyanthemum e H. carinatum. As máximas quantidades de ácido clorogênico, isoquercitrina, quercitrina e guaijaverina foram observadas, respectivamente, em H. campestre (1,458%), H. andinum (1,161%), H. carinatum (0,231%) e H. laricifolium (0,404%). Tais resultados fornecem suporte adicional para o significado quimiotaxonômico dos derivados diméricos de floroglucinol. Temperatura (40°C = 3,04%, 50°C = 2,21% e 60°C = 1,05%) e pressão (90 bar = 0,95%, 150 bar = 0,97% e 200 bar = 1,89%) afetaram de modo distinto o rendimento do extrato supercrítico de H. carinatum. Apesar do menor rendimento em comparação ao extrato n-hexano (6,09%), a extração com CO2 supercrítico provou ser mais seletiva que a maceração. Nas condições ideais (40°C, 90 bar e 180 minutos), a máxima recuperação de uliginosina B, carifenona A e carifenona B foi, respectivamente, 162,83, 376,33 e 48,79%. O modelo matemático empregado para simular o processo de extração foi apropriadamente correlacionado aos dados experimentais. Considerando as atividades biológicas, todas as espécies investigadas apresentaram um amplo espectro de ação antifúngica, assim como reduziram a migração dos neutrófilos. Os extratos de H. carinatum, H. linoides e H. myrianthum apresentaram os mais baixos valores de concentração inibitória mínima contra Cryptococcus neoformans (CIM £ 15,6 μg/mL), Rhodotorula mucilaginosa (CIM £ 62,5 μg/mL), Candida glabrata e C. tropicalis (CIM = 1,9-250 μg/mL). Para estas plantas, o efeito antiquimiotático variou entre 60 - 100% nas concentrações de 0,31 a 10 μg/mL. Os extratos mais ativos apresentaram elevada concentração de uliginosina B, japonicina A e hiperbrasilol B. Assim, as espécies de Hypericum nativas do sul do Brasil apresentam potencial como fonte de novos antifúngicos e anti-inflamatórios. / The genus Hypericum (Guttiferae = Clusiaceae) comprises 494 species placed in 36 taxonomic sections. The representatives of Central and South America belong primarily to sections Brathys and Trigynobrathys, the two largest sections with 87 and 52 species, respectively. In traditional medicine, these plants are used as antiseptic, diuretic, digestive and as healing agents. Such species have a strong tendency to accumulate dimeric phloroglucinol, besides benzophenones, benzopyrans, flavonoids and phenolic acids, metabolites whose antidepressant, antinociceptive, antimicrobial, antiproliferative and antioxidant activities are described. In view of the therapeutic potential, this work aimed to determine the main phenolic compounds present in flowers of Hypericum species native to southern Brazil (H. campestre, H. caprifoliatum, H. carinatum, H. connatum, H. linoides, H. myrianthum, H. polyanthemum and H. salvadorense) and to Peruvian Páramos (H. andinum and H. laricifolium); the supercritical CO2 extraction and analysis of the phenolic compounds of H. carinatum; the antifungal and antichemotactic activities of the lipophilic extracts from H. caprifoliatum, H. carinatum, H. linoides, H. myrianthum and H. polyanthemum. For the experiments, aerial parts in blossom were harvested (2008 - 2010). All collections were authorized by competent agencies of environmental protection. The extraction methods employed were static maceration, ultrasonic bath or supercritical CO2 (temperature = 40, 50 or 60ºC; pressure = 90, 120, 150 or 200 bar). HPLC analyses were carried out in reverse phase column (C18), isocratic system composed of acetonitrile, water and trifluoroacetic acid, and ultraviolet detection (220, 270 or 254 nm). Peaks were identified by comparison of retention times / co-injection with standards and quantified by calibration curve of the compounds. Antifungal and antichemotactic tests were performed using the broth microdilution assay and neutrophils migration inhibition method. The dimeric phloroglucinol uliginosin B (0.008 - 0.188%) and the flavonoid hyperoside (0.057 - 5.987%) were the main metabolite detected in flowers of the investigated species. Hypericum caprifoliatum and H. andinum displayed higher yields of these compounds, respectively. Japonicin A was found in seven species studied at concentrations that varied from 0.003 to 0.087% (H. myrianthum). The yield of hyperbrasilol B ranged from 0.006% in H. laricifolium to 0.011% in H. caprifoliatum. The benzopyrans (HP1 = 0.200%, HP2 = 0.225% and HP3 = 0.327%) and benzophenones (cariphenone A = 0.309% and cariphenone B = 0.062%) occurred exclusively in H. polyanthemum and H. carinatum. Maximum amounts of chlorogenic acid, isoquercitrin, quercitrin and guaijaverin were observed, respectively, in H. campestre (1.458%), H. andinum (1.161%), H. carinatum (0.231%) and H. laricifolium (0.404%). Such results provide a further support for the chemotaxonomic significance of the dimeric phloroglucinols. Temperature (40°C = 3.04%, 50°C = 2.21% and 60°C = 1.05%) and pressure (90 bar = 0.95%, 150 bar = 0.97% and 200 bar = 1.89%) critical did affect differently the yield of supercritical extract of H. carinatum. Despite lower yield in comparison to n-hexane extract (6.09%), supercritical CO2 extraction proved to be more selective than maceration. In optimal conditions (40°C, 90 bar and 180 minutes), the maximum amount of uliginosin B, cariphenone A and cariphenone B was, respectively, 162.83, 376.33 and 48.79%. Lastly, the mathematical model used in the process of supercritical extraction was properly correlated to the experimental data. Regarding the biological activities, all investigated species exhibited a broad spectrum of antifungal action as well as reduced neutrophils migration. Hypericum carinatum, H. linoides and H. myrianthum extracts presented the lowest value of minimum inhibitory concentration against Cryptococcus neoformans (MIC ≤ 15.6 μg/mL), Rhodotorula mucilaginosa (MIC ≤ 62.5 μg/mL), Candida glabrata and C. tropicalis (MIC range = 1.9 - 250 μg/mL). For these plants, the antichemotactic effect varied from 60-100% at concentrations of 0.31 to 10 μg/mL. The most active extracts were that presented high amounts of uliginosin B, japonicin A and hyperbrasilol B. Thus, the Hypericum species native to Southern Brazil show potential as source of new anti-infectives and anti-inflammatory drugs.
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Desenvolvimento e validação de metodologia analítica para extrato de passiflora incarnata linneaus / Development and validation of analytical method to Passiflora incarnata Linneaus extract

Lopes, Andréia Cristina Wildner Campos January 2013 (has links)
Um método confiável e eficiente por cromatografia líquida de alta eficiência (CLAE) foi desenvolvido para o controle de qualidade de extratos de P. incarnata. O método desenvolvido inclui uma estratégia original para identificação preliminar da espécie e operação simples baseada no modo de eluição isocrático. Este método foi validado para os flavonoides C-glicosilados vitexina e isovitexina, considerados marcadores da espécie e, aplicado na análise qualitativa e quantitativa de quatorze formulações comerciais com insumo vegetal composto exclusivamente de P. incarnata As análises foram realizadas com uma coluna C18 e à temperatura ambiente. Os comprimentos de onda de detecção foram 330 (vitexina e isovitexina) e 254 nm (rutina, marcador de contaminação). O método analítico foi linear para vitexina no intervalo de 5 - 40 ug/mL e para isovitexina no intervalo 5 - 60 ug/mL. Das quatorze amostras analisadas, oito eram em forma farmacêutica líquida (FFL) e seis em forma farmacêutica sólida (FFS). Seis amostras comerciais em FFL e seis amostras em FFS apresentaram perfil compatível com P. incarnata. As concentrações obtidas para as FFL foram vitexina 17,87 - 29,13 ug/mL e isovitexina 27,47 - 65,07 ug/mL, respectivamente. As FFS apresentaram concentração de vitexina entre 10,0 - 32,26 ug/mL e isovitexina 36,16 - 100,83 ug/mL. O método demonstrou ser confiável e eficiente para análise qualitativa e quantitativa de vitexina e isovitexina nos extratos; por esta razão foi considerado viável para a prática diária do controle de qualidade. A análise por cromatografia de líquida de alta eficiência acoplada com detector de espectroscopia de massas (CLAE-EM) foi realizada para investigar os principais fitoconstituintes, sete picos do extrato puderam ser resolvidos; e, forneceram fortes evidências sobre a composição química do extrato de P. incarnata. / A reliable and efficient method of high-performance liquid chromatography was developed for the quality control of Passiflora incarnata extracts. The quality control includes an original preliminary identification of this species and simple operation process based on isocratic elution. This method was validated for vitexin and isovitexin, C-glycoside flavonoids, considered markers of this species and applied to qualitative and quantitative analysis of fourteen commercial herbal medicines of P. incarnata extracts. Analysis was achieved on reversed-phase C18 column at ambient temperature. The wavelengths used for detection were 330 nm (vitexin and isovitexin) and 254 nm (rutin, a marker of contamination). Method was linear over vitexin concentration range of 540 g/mL and isovitexin 560 g/mL. Among of fourteen samples, eight were in liquid dosage form (LDF) and six in solid dosage form (SDF). Six commercial samples in LDF and six samples in SDF showed profile compatible with P. incarnata. Concentrations were determined for LDF vitexin 17.87  29.13 g/mL and isovitexin 27.47  65.07 g/mL. While SDF samples showed vitexin concentration range 10.00  32.26 g/mL and isovitexin 36.16  100.83 g/mL. The method demonstrated to be reliable and efficient for assay and qualitative analysis of vitexin and isovitexin in P. incarnata extracts; for that reason for practical application on quality control. Analysis were performed through high-performance liquid chromatography coupled with mass spectrometer detector (LC/MS) to investigate the main phytoconstituents, seven peaks from P. incarnata extract could be resolved; and provided strong evidences about the chemical composition of extracts.
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Mecanismos envolvidos na ação antinociceptiva e antiinflamatória do flavonóide miricitrina: estudos in vivo e in vitro" / Mechanisms involved in the antinociceptive and antiinflammatory activity of myricitrin: in vivo and in vitro studies

Meotti, Flavia Carla 02 May 2006 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The intake of flavonoids is closely associated with diminished risks of cancer, atherosclerosis and other chronic inflammation disturbance related. These compounds are described, mainly, by their anti-inflammatory and antioxidant activities. Myricitrin is a flavonoid that inhibits protein kinases and NO production. Therefore, the research of the mechanisms by which these compounds exerts their effects is extremely interesting for the therapeutic application. In this study, the antinociceptive and anti-inflammatory activities of myricitrin as well as its mechanisms of action were investigated. The systemic (p.o. or i.p.) and central (i.c.v. or i.t.) administration of myricitrin reduced in a dose-dependent manner the visceral pain induced by acetic acid. The i.p. treatment with myricitrin also prevented nociception induced by i.pl. injection of glutamate, capsaicin, PMA and by i.t. injection of glutamate, SP, TNF-α and IL-1β in mice. In addition, myricitrin treatment inhibited mechanical hyperalgesia induced by BK, but not that induced by epinephrine or PGE2 in rats. Western blot analysis revealed that myricitrin treatment fully prevented PKCα and PKCε activation by PMA in mice hindpaw. The antinociception caused by myricitrin in the acetic acid test was significantly reverted by Gi/o protein inactivation (pertussis toxin treatment); treatment with ATPgated K+ channel blocker (glibenclamide), CaCl2 and L-arginine (NO precursor) administration. However, myricitrin-induced antinociception was modified neither by antagonist opioid (naloxone) nor by neonatal capsaicin treatment (which depletes 80% of unmyelinated C fibers). In addition, myricitrin effects were not associated with sedative and muscle-relaxant action. In vitro assays using slices of cerebral cortex of rats revealed that myricitrin inhibited calcium transport in a depolarizing condition; however, at higher concentration, it inhibited calcium transport also in a non-depolarizing condition. Myricitrin increased nociceptive threshold in mechanical allodynia induced by both partial sciatic nerve ligation (neuropathic pain) and FCA i.pl. injection (inflammatory chronic pain). This same treatment decreased paw edema, morphological alterations and MPO activity (proinflammatory enzyme) in FCA hindpaw. On the other hand, it did not reduce neutrophils migration to inflammation site. Myricitrin produced potent antioxidant activity when assessed by Fe2+-induced lipid peroxidation. In conclusion, the present study showed that myricitrin exhibits antinociceptive and anti-inflammatory activity when analyzed in acute and chronic models of nociception. The mechanisms involved in the myricitrin beneficial effects included Gi/o protein activation, ATP- gated K+ channels opening, inhibition of PKC, NO synthesis, wedged of Ca2+ transport, inhibition of MPO activity and scavenger action. / O consumo de flavonóides através da dieta está positivamente relacionado com a diminuição do risco de câncer, ateroesclerose e agravamento de doenças relacionadas com inflamação e estresse oxidativo. Estes compostos são descritos, principlamente, pelas suas ações antiinflamatórias e antioxidantes. A miricitrina é um flavonóide que possui propriedades de inibir proteínas quinases, a síntese de NO entre outras. Desta forma, é de grande interesse a pesquisa destes compostos com finalidade terapêutica. No presente trabalho investigou-se as propriedades antinociceptivas e antiinflamatórias do flavonóide miricitrina, bem como os possíveis mecanismos envolvidos em tal processo. A administração sistêmica (oral ou i.p.) e central (i.c.v. ou i.t.) de miricitrina reduziu de forma dependente da dose o número de contorções abdominais induzidas pelo ácido acético. O tratamento i.p. com a miricitrina também preveniu a nocicepção induzida pela injeção i.pl. de glutamato, capsaicina e PMA, bem como, a nocicepção induzida pela injeção i.t. de glutamato, SP, TNF-α e IL-1β em camundongos. Além disso, o tratamento com miricitrina inibiu a hiperalgesia mecânica induzida pela BK, mas não aquela induzida pela epinefrina e PGE2 em ratos. Análises de Western blot revelaram que o tratamento com miricitrina inibiu completamente a ativação da PKCα e PKCε induzida pela injeção i.pl. de PMA. A antinocicepção causada pela miricitrina no teste do ácido acético foi significativamente revertida pelo pré-tratamento dos animais com o inativador da proteína Gi/o (toxina pertussis); com o bloqueador de canal de K+ (glibenclamida); com o precursor de NO (L-arginina) e o CaCl2. Entretanto, a antinocicepção provocada pela miricitrina não foi afetada pelo tratamento com antagonista opióide (naloxona); pelo tratamento neonatal com capsaicina (destrói 80% das fibras sensorias não mielinizadas do tipo C) e não está relacionada com uma ação sedativa, relaxante muscular ou hipotérmica do composto. Além disso, ensaios in vitro em fatias de córtex cerebral de ratos revelaram que a miricitrina inibe o transporte de cálcio em uma condição despolarizante, embora, quando em alta concentração, miricitrina inibe o transporte de cálcio também em condição nãodespolarizante. A miricitrina reduziu a alodínia mecânica induzida pela ligadura parcial de nervo ciático (dor neuropática) e pela injeção i.pl. de FCA (dor inflamatória crônica). Este mesmo tratamento reduziu o edema de pata, as alterações morfológicas e a atividade da MPO (enzima pró-inflamatória) na pata injetada com FCA, porém não reduziu a migração de neutrófilos ao local da inflamação. A miricitrina mostrou potente ação antioxidante frente à peroxidação lipídica induzida por Fe2+. De acordo com o presente trabalho pode-se concluir que a miricitrina é dotada de atividade antinociceptiva e antiinflamatória quando avaliada em modelos de nocicepção aguda e crônica. Os mecanismos de sua ação antinociceptiva e antiinflamatória incluem a ativação de proteína Gi/o e abertura de canais de K+, a inibição da PKC, da síntese de NO, bloqueio do transporte de Ca2+, inibição da atividade da MPO e neutralização de radicais livres.
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Biomassa, teores de nutrientes, espilantol e atividade antioxidante em plantas de jambu (Acmella ciliata Kunth) sob adubações mineral e orgânica /

Borges, Luciana da Silva , 1981- January 2009 (has links)
Resumo: A produção orgânica é um sistema que permite alcançar bons níveis de produtividade, evitando ao mesmo tempo os riscos de contaminação química do agricultor, dos consumidores e do meio ambiente. Pelo fato da planta de jambu ser bastante utilizada como medicamento alternativo e por indústrias de cosméticos, vem aumentando o interesse devido às suas características físico-químicas. No entanto, as pesquisas sobre essa cultura ainda são muito incipientes. Existem poucos trabalhos e uma insuficiente diversidade de análises físico-químicas que possam caracterizar e diferenciar os tipos de cultivo em relação ao jambu. Assim, o objetivo do presente estudo foi analisar o óleo essencial e os compostos antioxidantes em diferentes partes de jambu (folha e inflorescência) cultivado sob adubação orgânica e mineral, além de caracterizar os minerais no solo e nas plantas, nos diferentes tipos de cultivo. O experimento foi conduzido na Fazenda Experimental São Manuel (São Manuel-SP), pertencente à Faculdade de Ciências Agronômicas - UNESP, campus de Botucatu) e na mesma época. O delineamento estatístico foi em blocos casualizados em esquema fatorial (2 x 6), duas fontes de adubação (orgânica e mineral) e seis doses de esterco de curral e uréia, com quatro repetições para todas as análises efetuadas, exceto para as características de potencial antioxidante e espilantol, que foram utilizadas três repetições. Os experimentos realizados apresentaram como tratamentos seis doses de adubação mineral (0, 30, 60, 90, 120, 150 g m-2 de uréia), aplicadas parceladas em duas vezes e seis doses de adubação orgânica (0, 2, 4, 6, 8 e 10 kg m-de esterco de curral), aplicadas no plantio. As características avaliadas foram teores de nutrientes na parte aérea, altura de plantas, massa fresca e seca, composição química do óleo essencial, teor de acido ascórbico; potencial... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The organic production it is a system that will achieve good levels of productivity, while avoiding the risk of chemical contamination of farmers, consumers and the environment. Because the plant jambu be widely used as alternative medicine and cosmetic industries, has been increasing interest due to their physical and chemical characteristics. However, the researches on this crop are still very incipient. There is little work and an insufficient variety of physical and chemical analysis that can characterize and differentiate the types of cultivation on the jambu.The purpose of this study was to analyze the essential oil and the antioxidant compounds in different parts of jambu (leaf and inflorescence) grown under organic and mineral fertilizer, and characterize the minerals in soil and plants in different types of cultivation. The experiment was conducted led in (Experimental Farm São Manuel (São Manuel-SP), belonging to the Faculty of Agricultural Sciences - UNESP, campus of Botucatu) and at the same time. The statistical design was factorial (2 x 6), two sources of fertilizer (organic and mineral) and six doses of the kraal manure and urea, with four replications for all analysis performed, except for the characteristics of potential antioxidant and spilantol, which were used three repetitions. The experiments presented treatments as six doses of conventional fertilization (0, 30, 60, 90, 120, 150 g m-2, urea), applied in two split doses of fertilizer and six non-conventional (0, 2, 4, 6, 8 and 10 kg m-2 of the kraal manure), applied at planting. The characteristics were nutrient content in shoot, plant height, fresh and dry weight, chemical composition of essential oil, ascorbic acid content, antioxidant potential, and presence of pesticides. The results show that the compounds were present in this study were trans-caryophyllene, germacrene D, L-dodecene and espatulenol and... (Complete abstract click electronic access below) / Orientador: Giuseppina Pace Pereira Lima / Coorientador: Rumy Goto / Banca: Márcia Ortiz Mayo Marques / Banca: Atila Francisco Mogor / Mestre

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