• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 4
  • Tagged with
  • 4
  • 4
  • 4
  • 3
  • 3
  • 2
  • 2
  • 2
  • 2
  • 2
  • 2
  • 2
  • 2
  • 1
  • 1
  • 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.
1

Fitoqu?mica e atividades biol?gicas de Miconia ferruginata DC. (Melastomataceae)

Barroso, Poliana Ribeiro 24 April 2015 (has links)
Submitted by Nivaldo Melo (nivaldo.melo@ufvjm.edu.br) on 2015-11-30T17:33:07Z No. of bitstreams: 2 poliana_ribeiro_barroso.pdf: 8014555 bytes, checksum: 744e34507fbe1725f369a03ee8c97123 (MD5) license_rdf: 23898 bytes, checksum: e363e809996cf46ada20da1accfcd9c7 (MD5) / Approved for entry into archive by Rodrigo Martins Cruz (rodrigo.cruz@ufvjm.edu.br) on 2015-12-01T16:10:43Z (GMT) No. of bitstreams: 2 poliana_ribeiro_barroso.pdf: 8014555 bytes, checksum: 744e34507fbe1725f369a03ee8c97123 (MD5) license_rdf: 23898 bytes, checksum: e363e809996cf46ada20da1accfcd9c7 (MD5) / Made available in DSpace on 2015-12-01T16:10:43Z (GMT). No. of bitstreams: 2 poliana_ribeiro_barroso.pdf: 8014555 bytes, checksum: 744e34507fbe1725f369a03ee8c97123 (MD5) license_rdf: 23898 bytes, checksum: e363e809996cf46ada20da1accfcd9c7 (MD5) Previous issue date: 2015 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (Capes) / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico (CNPq) / Funda??o de Amparo ? Pesquisa do estado de Minas Gerais (FAPEMIG) / As plantas medicinais s?o fontes promissoras de novas drogas, em que a regi?o do Cerrado se destaca pela sua vasta biodiversidade. Dentre as plantas medicinais utilizadas nesta regi?o se encontra a esp?cie Miconia ferruginata DC. que ? conhecida como pixirica-do-campo ou babaten?o. Esta esp?cie ? utilizada no tratamento de doen?as de pele, e outras de origens inflamat?rias, parasit?rias e infecciosas, por?m os estudos qu?micos s?o escassos. Assim, os objetivos deste trabalho foram avaliar o perfil qu?mico e o potencial biol?gico da M. ferruginata (Melastomataceae). A esp?cie foi coletada no munic?pio de Diamantina, MG do qual foram preparados os extratos aquosos e etan?licos das folhas/flores e do caule. Por meio da triagem fitoqu?mica e das an?lises de CLAE-DAD-EM obteve-se um perfil qu?mico rico em compostos fen?licos. Foi poss?vel a identifica??o da presen?a de taninos, ?cidos fen?licos, flavonoides, e derivados glicosilados da quercetina. Pela an?lise dos constituintes vol?teis por CG-EM foi poss?vel identificar a presen?a de quatorze compostos, sendo eles pertencentes as classes dos sesquiterpenos, hidrocarbonetos, monoterpenos, fenilpropanoides e alco?is. No qual os sesquiterpenos ?-cariofileno e ?-humuleno foram os compostos majorit?rios, os quais s?o associados na literatura a diversas atividades biol?gicas, em especial a a??es anti-inflamat?rias, antif?ngicas e antitumorais. A an?lise das fra??es por CG-EM e CLAE-DAD foi poss?vel identificar catequinas, ?cido g?lico e flavon?is nos extratos aquosos e ?steres graxos e as subclasses das flavonas e flavon?is nos extratos etan?licos. Nas avalia??es biol?gicas os extratos etan?licos e aquosos apresentaram baixa toxicidade em c?lulas de mam?feros, em que a concentra??o selecionada para a avalia??o das demais atividades biol?gicas foi de at? 500 ?g/mL. Para a atividade antitumoral, os extratos apresentaram um grande potencial concentra??o dependente, com valores de IC50 variando de 56,44 a 180,4 ?g/mL. Bem como o tempo de exposi??o aumentou a pot?ncia de todos os extratos. Tamb?m foi observado que os extratos aquosos promoveram a inibi??o da prolifera??o de linf?citos estimulados por mit?genos, apresentando uma efic?cia em rela??o ? dexametasona, de 39,94% para o extrato das folhas a 45 ?g/mL, e de 57,3%, 137,4% e 251,8% para os extratos do caule a 15, 20 e 30 ?g/mL, respectivamente. Este efeito proliferativo pode estar relacionado ao potencial anti-inflamat?rio da M. ferruginata, relatada na medicina popular. Possivelmente, as atividades biol?gicas est?o relacionadas ao rico perfil qu?mico desta esp?cie, principalmente em compostos fen?licos. Para as atividades antimicrobianas, tripanocida 9 e leishmanicida n?o foram observadas a inibi??o do crescimento ou toxicidade frentes as cepas avaliadas. Desta forma este trabalho contribuiu para o conhecimento qu?mico e biol?gico da M. ferruginata. Por?m ensaios futuros utilizando as fra??es e subst?ncias isoladas, se fazem necess?rios para fortalecer os dados aqui apresentados e para demonstrar quais os mecanismos moleculares envolvidos nas atividades biol?gicas investigadas. / Disserta??o (Mestrado) ? Programa de P?s-gradua??o em Ci?ncias Farmac?uticas, Universidade Federal dos Vales do Jequitinhonha e Mucuri, 2015. / ABSTRACT Medicinal plants are reassuring sources of new drugs, in which the Cerrado region stands out for its broad biodiversity. Among the medicinal plants used in this same region is the species Miconia ferruginata DC. which is also known as pixirica-docampo or babaten?o. This species is used in the treatment of skin diseases, and other inflammatory, infectious and parasitic sources, despite the chemical studies about it are lacking. Therefore, the objectives of this study were to evaluate the chemical profile and biological potential of the M. ferruginata (Melastomataceae).The species was collected in Diamantina, MG, in which it was prepared for water and ethanol extraction of the leaves/flowers and stem. Through phytochemical screening and analysis of HPLC-MSDAD, we obtained a rich chemical profile in phenolic compounds. The identification of tannins, phenolic acids, flavonoids, glycosides of quercetin and derivativeshas been detected. For the analysis of volatile constituents by GC-MS, it was possible to identify the presence of fourteen compounds, namely belonging classes of sesquiterpenes, hydrocarbons, monoterpenes, phenylpropanoids and alcohols. For that,? and?- caryophyllene, humulenesesquiterpenes were the main components, which are associated in the literature several biological activities, especially anti-inflammatory, antifungal and antitumor activities.In the analysis of the fractions by GC-MS and HPLC-DAD, we identified catechins, gallic acid and flavonols in aqueous extracts,including fatty esters and subclass of flavones and flavonols in ethanol extracts. Within the biological evaluations, aqueous and ethanolic extracts showed low toxicity to mammalian cells, wherein the concentration selected for analysis of other biological activities was up to 500 ?g/mL. For antitumor activity, the extracts showed a great potential concentration-dependent, with IC50 values ranging from 56.44 to 180.4 ?g/mL. Just as the exposure time increased the potency of all extracts, it was also observed that aqueous extracts promoted inhibition of the proliferation of mitogen-stimulated lymphocytes, showing a efficacy when compared to dexamethasone, 39.94% for the extract from the leaves of 45 ?g/mL, and 57.3%, 137.4% and 251.8% for the extracts of stem of 15.20 and 30 ?g/mL, respectively. This proliferative effect may be related to the anti-inflammatory potential of M. ferruginata, reported in folk medicine. Possibly, the biological activities are related to the rich chemical profile of this species, mainly in phenolic compounds. For the antimicrobial, trypanocidal and leishmanicidal activities, we have not observed growth inhibition or toxicity fronts of the evaluated strains. Thus 11 this work contributed to the chemical and biological knowledge of M. ferruginata. Nevertheless, future trials using isolated fractions and substances are needed to strengthen the data presented here and to demonstrate the molecular mechanisms involved in the biological activities investigated. It is likely that the biological activities are related to the rich chemical profile of this species, mainly regarding phenolic compounds. For antimicrobial activity, trypanocidal and leishmanicidal, it was not observed growth inhibition or toxicity regarding the evaluated strains. Thus, this work contributed to the chemical and biological knowledge of the M. ferruginata. However, future trials using isolated fractions and substances are needed to strengthen the data presented here and to demonstrate the molecular mechanisms involved in the biological activities hereby investigated.
2

Atividades biol?gicas e composi??o qu?mica dos ?leos essenciais de Achyrocline satureoides (Lam) DC. e Ageratum conyzoides L. encontradas no semi?rido baiano

Gon?alves, Jacqueline Miranda 28 September 2015 (has links)
Submitted by Ricardo Cedraz Duque Moliterno (ricardo.moliterno@uefs.br) on 2016-01-19T23:08:21Z No. of bitstreams: 1 TESE DOUTORADO VERS?O FINAL.pdf: 3041272 bytes, checksum: e0025693076836f6a3804cc2aaf6a529 (MD5) / Made available in DSpace on 2016-01-19T23:08:21Z (GMT). No. of bitstreams: 1 TESE DOUTORADO VERS?O FINAL.pdf: 3041272 bytes, checksum: e0025693076836f6a3804cc2aaf6a529 (MD5) Previous issue date: 2015-09-28 / Essential oils are complex mixtures of various isolates of plant secondary metabolites. Due to the increased use of these aromatic compounds, research has been developed, and the development of new products. This study analyzed the antimicrobial, cytotoxic and immunomodulatory activities in addition to the phytochemical profile of essential oils Achyrocline satureoides and Ageratum conyzoides. The micro-organisms most sensitive to oils were Staphylococcus aureus CCMB 262 and Candida kruzei CCMB 287. The essential oil of A. conyzoides was considered non-toxic in the tested conditions. In the assessment of the immune response induced by oils, although they were not statistically significant differences between the concentrations tested and control, it was observed that the essential oils inhibited the production of IL-8 and IL-12 cytokines with exception of the species A. satureoides at a concentration of 100 mg / mL. This behavior may suggest the capacity reduction of the inflammatory response. The chromatographic analysis of essential oils of A. satureoides demonstrated a chemical profile consistent with the literature where the major components were ?-Pinene, E-caryophyllene, ?-copaene, ?-humulene, d-cadinene. Since the analysis of oils A. conyzoides showed conflicting results in the literature which suggests a new chemotype, since the presence of precocenos the chemical analysis was not observed. / Os ?leos essenciais s?o misturas complexas de metab?litos secund?rios isolados de diversas plantas. Devido ao aumento do uso destes compostos arom?ticos, pesquisas v?m sendo desenvolvidas, al?m do desenvolvimento de novos produtos. O presente trabalho analisou as atividades antimicrobiana, citot?xica e imunomoduladora, al?m do perfil fitoqu?mico de ?leos essenciais de Achyrocline satureoides e Ageratum conyzoides. Os micro-organismos mais sens?veis aos ?leos foram Staphylococcus aureus CCMB 262 e Candida kruzei CCMB 287. O ?leo essencial de A. conyzoides foi considerado at?xico nas condi??es testadas. Em rela??o ? avalia??o da resposta imune induzida pelos ?leos, apesar de n?o terem sido encontradas diferen?as estatisticamente significantes entre as concentra??es testadas e o controle, p?de-se observar que os ?leos essenciais inibiram a produ??o das citocinas IL-8 e IL-12, com exce??o da esp?cie A. satureoides na concentra??o de 100 ?g/mL. Este comportamento pode sugerir a capacidade de redu??o da resposta inflamat?ria. As an?lises cromatogr?ficas dos ?leos essenciais de A. satureoides demonstrou um perfil qu?mico em concord?ncia com a literatura onde os componentes majorit?rios foram ?-Pineno, E-Cariofileno, ?-Copaeno, ?-Humuleno, d-Cadineno. J? as an?lises dos ?leos de A. conyzoides apresentou resultados divergentes da literatura o que nos sugere um novo quimiotipo, uma vez que n?o foi observada a presen?a de precocenos nas an?lises qu?micas.
3

Atividade anticoagulante, antioxidante e antitumoral de heterofucanas da alga Dictyopteris delicatula (Lamouroux, 1809)

Magalhaes, Kaline Dantas 02 December 2011 (has links)
Made available in DSpace on 2014-12-17T14:13:58Z (GMT). No. of bitstreams: 1 KalineDM_DISSERT.pdf: 984274 bytes, checksum: 8150a2011f0eac140bc8113ffa4bc1ea (MD5) Previous issue date: 2011-12-02 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico / In the present study, six families of sulfated polysaccharides were obtained from seaweed Dictyopteris delicatula (Lamouroux, 1809) and their anticoagulant, antioxidant and antitumor activities were evaluated. All fractions showed anticoagulant activity on aPTT assay, but not on PT assay. Fractions also exhibited total antioxidant activity, superoxide radical scavenging capacity and ferric chelating property. Thus, six fractions (F0.5v, F0.7v, F1.0v, F1.3v, F1.5v e F2.0v) we obtained by proteolytic digestion, followed by acetone fractionation and molecular sieving on Sephadex G-100. Chemical analyses demonstrated that all polysaccharides contain heterofucans composed mainly of fucose, xylose, glucose, galactose, uronic acid, and sulfate. Any fractions changed the PT. However, all fractions were able on double the aPPT on a dose-dependent manner. The heterofucans F0.7v and F1.0v showed low anticoagulant activity while F1.5v presented the most prominent anticoagulant activity .When compared to Clexane?, a low molecular weight heparin, at same concentration F1.5v presented similar anticoagulant activity. The fucans F0.5v and F0.7v at 1.0 mg/mL showed high ferric chelating activity (~45%), whereas fucans F1.3v (0.5 mg/mL) showed considerable reducing power, about 53.2% of the activity of vitamin C. The fucan F1.5v presented the most prominent anticoagulant activity. The best antiproliferative activity was found with fucans F1.3v and F0.7v. However, F1.3v activity was much higher than F0.7v inhibiting almost 100% of HeLa cell proliferation. These fucans have been selected for further studies on structural characterization as well as in vivo experiments, which are already in progress / No presente estudo, seis popula??es de polissacar?deos sulfatados foram obtidas a partir da alga Dictyopteris delicatula (Lamouroux, 1809) e suas atividades anticoagulante, antioxidante e antitumoral avaliadas. Deste modo, as seis fra??es (F0.5v, F0.7v, F1.0v, F1.3v, F1.5v e F2.0v) foram obtidas por prote?lise seguida por fracionamento de acetona e gel filtra??o molecular Sephadex G-100. Todas as fra??es apresentaram atividade anticoagulante frente ao ensaio de aPTT, mas n?o sobre o ensaio de PT. As heterofucanas exibiram atividade antioxidante total, capacidade em sequestrar radicais super?xido e propriedade de quelar ferro. As an?lises qu?micas demonstraram que todos os polissacar?deos cont?m heterofucanas composta principalmente por fucose, xilose, glicose, galactose, ?cido ur?nico, e sulfato. Nenhuma das fra??es alterou o PT. Entretanto, todas as fra??es foram capazes de dobrar o aPTT de uma maneira dose dependente. As heterofucanas F0.7v e F1.0v demonstraram baixa atividade anticoagulante, enquanto a F1.5v apresentou a maior atividade anticoagulante e quando comparada com Clexane?, uma heparina de baixo peso molecular, em mesma concentra??o, apresentou antividade anticoagulante semelhante. As fucanas F0.5v e F0.7v a 1,0 mg/mL mostraram alta atividade de quela??o ferica (~ 45%), enquanto a fucana F1.3v (0,5 mg/mL) mostrou consider?vel potencial redutor, cerca de 53,2% da atividade da vitamina C. A melhor atividade antitumoral foi encontrada nas fucanas F1.3v e F0.7v. No entanto, a atividade F1.3v foi muito superior a F0,7v, quase 100% de inibi??o da prolifera??o de c?lulas HeLa (c?lula de c?ncer de colo de ?tero). Estas fucanas foram selecionadas para novos estudos sobre caracteriza??o estrutural, bem como em experimentos in vivo, que j? est?o em andamento / 2020-01-01
4

An?lises estruturais e atividades biol?gicas de exopolissacar?deo extra?do do fungo comest?vel pleurotus Sajor-Caju e de seu derivado sulfatado quimicamente.

Telles, Cinthia Beatrice da Silva 11 February 2010 (has links)
Made available in DSpace on 2014-12-17T14:03:32Z (GMT). No. of bitstreams: 1 CinthiaBST.pdf: 1239764 bytes, checksum: b0f986e10d6574ec55e837255b634b41 (MD5) Previous issue date: 2010-02-11 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / The exopolysaccharides are extracellular compounds produced by some species of fungi and bacteria. It is suggested that these molecules, even when in the form of complex polysaccharide-peptide, are the main bioactive molecules of many fungus. Some of the biological activities displayed by these compounds can be accentuated and others may arise when you add chemically polar or nonpolar groups to polysaccharides. The fruiting body of Pleurotus sajor-caju produces a heteropolysaccharide with antineoplastic and antimicrobial activity, but other biological activities of this polymer have not been evaluated. In this work the exopolysaccharide of Pleurotus sajor-caju was sulfated chemically and structurally characterized. We also evaluated the antiproliferative, antioxidant and anticoagulant activities from native exopolysaccharide (PN) and its sulfated derivated (PS). Polyacrylamide gel electrophoresis, infrared spectroscopy and nuclear magnetic resonance (??C) proved successful in sulfation of PN to obtain PS. Analysis by gas chromatography-mass spectroscopy showed that PN and PS are composed of mannose, galactose, 3-O-methyl-galactose and glucose in proportion percentage of 44,9:16,3:19,8:19 and 49, 7:14,4:17,7:18,2, respectively. The percentage of sulfate found in PS was 22.5%. Antioxidants assays revealed that the sulfation procedure affects differently the activities of exopolysaccharides, while the total antioxidant capacity, the scavenging activity of superoxide radical and ferric chelating were not affected by sulfation, on the other hand the chemical modification of PN enhanced the scavenging activity of hydroxyl radical and reducing power. PS also showed anticoagulant activity in a dose-dependent manner and clotting time was 3.0 times higher than the baseline value in APTT at 2 mg/mL. The exopolysaccharide not presented antiproliferative activity against HeLa tumor cells, but PS affects the cellular proliferation in a time-dependent manner. After 72 h, the inhibition rate of PS (2.0 mg/mL) on HeLa cells was about 60%. The results showed that PN sulfation increase some of their activities. / Os exopolissacar?deos s?o compostos extracelulares produzidos por algumas esp?cies de fungos e bact?rias. ? sugerido que estas mol?culas, inclusive quando na forma de complexo polissacar?deo-pept?deo, s?o as principais mol?culas bioativas de v?rios fungos. Muitas das atividades biol?gicas apresentadas por esses compostos podem ser acentuadas e outras podem surgir quando se adiciona quimicamente aos polissacar?deos grupamentos polares ou apolares. O corpo de frutifica??o de Pleurotus sajor-caju produz um heteropolissacar?deo com atividade antioneopl?sica e antimicrobiana, contudo outras atividades biol?gicas desse pol?mero ainda n?o foram avaliadas. Neste trabalho o exopolissacar?deo de Pleurotus sajor-caju foi sulfatado quimicamente e caracterizado estruturalmente. Tamb?m foram avaliadas as atividades antiproliferativa, antioxidante e anticoagulante do exopolissacar?deo nativo (PN) e de seu derivado sulfatado (PS). Eletroforese em gel de agarose, espectroscopia de infravermelho e resson?ncia magn?tica nuclear (??C) comprovaram o sucesso na sulfata??o de PN para a obten??o de PS. An?lise por cromatografia gasosa acoplada a espectroscopia de massa mostrou que PN e PS s?o constitu?dos de manose, galactose, 3-O-metil-galactose e glicose na propor??o percentual de 44,9:16,3:19,8:19 e 49,7:14,4:17,7:18,2, respectivamente. O percentual de sulfato encontrado em PS foi de 22,5%. Testes antioxidantes revelaram que o processo de sulfata??o influencia de forma diferente nas atividades do exopolissacar?deo. Enquanto a capacidade antioxidante total, a capacidade de seq?estro de radical super?xido e a quela??o f?rrica n?o foram influenciadas pela sulfata??o, essa potencializou a atividade seq?estradora de radicais hidroxila e o poder redutor do exopolissacar?deo. Ap?s o processo de sulfata??o o exopolissacar?deo passou a apresentar atividade anticoagulante de forma dose-dependente, triplicando o tempo de coagula??o em rela??o ao controle numa concentra??o de aproximadamente 2 mg/mL. O exopolissacar?deo n?o apresentou atividade antiproliferativa frente ?s c?lulas tumorais HeLa, por?m ap?s sulfata??o ele passou a apresentar essa atividade de forma tempo- ependente, chegando a inibir em 60% a taxa de prolifera??o das c?lulas com 2 mg/mL, ap?s 72 h de exposi??o. Os resultados aqui obtidos mostraram que a sulfata??o do exopolissacar?deo potencializou algumas de suas atividades.

Page generated in 0.1135 seconds