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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.
1

Alcaloides ind?licos de Aspidosperma pyrifolium: estudo fitoqu?mico e dados espectrosc?picos

Santos, Sarah Pollyana Dias dos 14 July 2016 (has links)
Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2017-04-03T19:41:30Z No. of bitstreams: 1 SarahPollyanaDiasDosSantos_DISSERT.pdf: 10111393 bytes, checksum: 44cc6b08e8b21238733661e330e1b811 (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2017-04-05T19:31:53Z (GMT) No. of bitstreams: 1 SarahPollyanaDiasDosSantos_DISSERT.pdf: 10111393 bytes, checksum: 44cc6b08e8b21238733661e330e1b811 (MD5) / Made available in DSpace on 2017-04-05T19:31:53Z (GMT). No. of bitstreams: 1 SarahPollyanaDiasDosSantos_DISSERT.pdf: 10111393 bytes, checksum: 44cc6b08e8b21238733661e330e1b811 (MD5) Previous issue date: 2016-07-14 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico (CNPq) / Aspidosperma pyrifolium Mart., esp?cie nativa da caatinga com grande ocorr?ncia no nordeste, conhecida popularmente como pereiro, utilizada na medicina popular no tratamento de doen?as e enfermidades. Consta na literatura diversos trabalhos realizados, relatando a presen?a de classes de compostos org?nicos como alcaloides, entre outras, que seriam respons?veis por propriedades terap?uticas existentes nessa esp?cie. O estudo fitoqu?mico de A. pyrifolium, das fra??es da semente e cascas do fruto, utilizando m?todos cromatogr?ficos cl?ssicos e purifica??o por CLAE, nos permitiu o isolamento de tr?s compostos. A partir da fra??o hex?nica das cascas do fruto (APCF-H) foi isolado o triterpeno ?cido betul?nico, n?o relatado anteriormente na esp?cie A. pyrifolium. Das fra??es diclorometano (APSE/DCM) e acetato de etila 50% dicloromentano (APSEA/50% DCM) das sementes foi poss?vel o isolamento do alcaloide plumerano pentac?clico aspidospermina, do alcaloide ?-carbolina glicosilado Cordifolina, n?o descrito anteriormente na esp?cie e outro composto do tipo ?-carbolina que n?o possui uma estrutura elucidada at? o momento. O extrato das sementes fra??o diclorometano (APSE/DCM) foi analisado por CG/EM (cromatografia gasosa acoplada a espectrometria de massa) e seus dados foram comparados com dados na literatura em banco de dados (NIST08.LIB), foi identificada a presen?a dos alcaloides 1-acetil-aspidospermidina, aspidospermina e pirifolina, dentre outros compostos minorit?rios. A avalia??o da atividade antioxidante, pelo m?todo sequestrador de radical livre de DPPH (2,2-difenil-1picril-hidrazila), da fra??o APSE/DCM apresentou um percentual de atividade antioxidande m?ximo (AA% m?ximo) de 83,68%, com concentra??o inibit?ria 50% (IC50) 133,4867 ? 2,22. A fra??o das sementes fra??o diclorometano (APSE/DCM) foi avaliada em rela??o ? toxicidade contra Artemia salina, tendo em vista que j? existiam relatos da toxicidade nas folhas de A. pyrifolium, comprovamos a toxicidade aguda nas fra??o das sementes diclorometano com concentra??o letal m?dia (CL50) em 24 horas de 1,1524 ?g.ml-1, sendo consideradas t?xicas as esp?cies que apresentam CL50 inferior a 1000 ?g.ml-1. Na segunda parte do trabalho foi realizado um levantamento bibliogr?fico de alcaloides do tipo ?-carbolina de ocorr?ncia natural, com suas estruturas, atividades relatadas e um banco de dados com seus deslocamentos qu?micos em RMN 1H e 13C, totalizando 169 alcaloides descritos na literatura, do per?odo de 1992 a 2016, agrupados em quatro principais grupos, denominados ?-carbolina, dihidro-?-carbolina, tetrahidro-?-carbolina e os ?-carbolinas divergentes, este levantamento auxiliar? na elucida??o estrutural de novas mol?culas. / Aspidosperma pyrifolium Mart., a native species of the caatinga with great occurrence in the northeast, known perpularmente as pereiro, used in popular medicine in the treatment of diseases and diseases. There are several studies carried out in the literature, reporting the presence of classes of organic compounds such as alkaloids, among others, that would be responsible for the therapeutic properties of this species. The phytochemical study of A. pyrifolium, seed fractions and fruit peels using classical chromatographic methods and purification by HPLC allowed us to isolate three compounds. From the hexanic fraction of fruit peels (APCF-H) was isolated the betulinic acid triterpene, not previously reported in the A. pyrifolium species. From the dichloromethane (APSE/DCM) and ethyl acetate 50% dichloromethane (APSEA / 50% DCM) fractions of the seeds, it was possible to isolate the pentacyclic pentameric aspidospermine alkaloid from the glycosylated ?-carboline alkaloid Cordifolina, not previously described in the species and another compound of the ?-carboline type that does not have a structure elucidated until the moment. The extract of the seeds dichloromethane fraction (APSE/DCM) was analyzed by GC/MS (gas chromatography coupled to mass spectrometry) and its data were compared with data in the literature in database (NIST08.LIB), the presence of the alkaloids 1-acetyl-aspidospermidine, aspidospermine and pyrifoline, among other minor compounds. The antioxidant activity evaluation of the APSE/DCM fraction showed a percentage of maximum antioxidant activity (AA% maximum) of 83.68%, with the free radical sequestration method of DPPH (2,2-diphenyl-1-picryl-hydrazila). Inhibitory concentration 50% (IC50) 133.4867 ? 2.22. The fraction of the seeds dichloromethane fraction (APSE/DCM) was evaluated in relation to the toxicity against Artemia salina, considering that there were already reports of the toxicity in the leaves of A. pyrifolium, we verified the acute toxicity in the seed dichloromethane fraction with average lethal concentration (CL50) in 24 hours of 1.1524 ?g.ml-1, species with CL50 less than 1000 ?g.ml-1 being considered toxic. In the second part of the work a bibliographic survey of naturally occurring ?-carboline alkaloids with their structures, reported activities and a database with their chemical displacements in 1H and 13C NMR were carried out, totaling 169 alkaloids described in the literature. From 1992 to 2016, grouped into four main groups, named ?-carboline, dihydro-?-carboline, tetrahydro-?-carboline and the divergent ?-carbolines, this survey will aid in the structural elucidation of new molecules.

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