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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

Flavonóides e terpenóides de três espécies do gênero Erythroxylum e suas atividades biológicas

Barreiros, Marizeth Libório January 2005 (has links)
Submitted by Ana Hilda Fonseca (anahilda@ufba.br) on 2016-09-12T16:37:09Z No. of bitstreams: 2 Tese Marizeth Libório Barreiros 1.pdf: 150250 bytes, checksum: 618619e04d03e4b90981a902ab9a027d (MD5) Tese Marizeth Libório Barreiros 2.pdf: 2746950 bytes, checksum: a7a2f2ebf5b33116946cc6a98436887a (MD5) / Approved for entry into archive by NUBIA OLIVEIRA (nubia.marilia@ufba.br) on 2016-09-12T17:48:56Z (GMT) No. of bitstreams: 2 Tese Marizeth Libório Barreiros 1.pdf: 150250 bytes, checksum: 618619e04d03e4b90981a902ab9a027d (MD5) Tese Marizeth Libório Barreiros 2.pdf: 2746950 bytes, checksum: a7a2f2ebf5b33116946cc6a98436887a (MD5) / Made available in DSpace on 2016-09-12T17:48:56Z (GMT). No. of bitstreams: 2 Tese Marizeth Libório Barreiros 1.pdf: 150250 bytes, checksum: 618619e04d03e4b90981a902ab9a027d (MD5) Tese Marizeth Libório Barreiros 2.pdf: 2746950 bytes, checksum: a7a2f2ebf5b33116946cc6a98436887a (MD5) / Este trabalho descreve o estudo fitoquímico dos extratos clorofórmicos e acetato de etila de três espécies do gênero Erythroxylum, E. nummularia, E. passerinum e E. barbatum, além da realização de testes de atividade biológicas com os extratos e as substâncias isoladas visando obter substâncias bioativas. O gênero Erythroxylum pertence a família Erythroxylaceae que compreende aproximadamente 250 espécies distribuídas nas regiões tropicais com extensas áreas de diversidade na América do Sul e Madagascar. A partir das folhas de E. nummularia foram isolados os flavonóides, 7,4-dimetilquercetina, quercetina, quercetina-3-glicopiranosídeo e epicatequina. A partir dos frutos de E. passerinum foram isolados dois novos diterpenos, 3-metoxi-2,8,12-trihidroxi-15-oxi-10-hidroxi-rianodano e o 10-dihidroxi-2,6,12-triidroxi-15-oxi-rianodano. Este é o primeiro registro desses diterpenos na família Erythroxylaceae. Enquanto que E. barbatum levou ao isolamento de quercetina-3-ramnopiranosídeo, 7,4-dimetilquercetina–rutinosídeo, quercetina-3-rutinosídeo, quercetina, epicatequina, além de -amirina, palmitato de -amirinila, lupeol, -sitosterol e 132 -(OH)-Clorofila a. As substâncias foram isoladas através de métodos cromatográficos e suas estruturas foram elucidadas através da análise dos dados obtidos pelos espectros de RMN de 1H e 13C, UV e EM. Os extratos e algumas substâncias foram submetidos a testes de atividade citotóxica, larvicida, moluscicida e imunomoduladora. Nestes testes o extrato acetato de etila dos frutos de E. passerinum apresentou 100% de atividade para larvas da Artemia salina na concentração de 100 ppm. Esta atividade é devido, provavelmente, a presença das substâncias 3-metoxi-2,6,12-trihidroxi-15-oxi-10-hidroxi-rianodano e 10-dihidroxi-2,6,12-triidroxi-15-oxi-rianodano.. A substância 3-metoxi-2,6,12-trihidroxi-15-oxi-10-hidroxi-rianodano foi tóxica frente as larvas da Artemia salina causando 50% de mortes numa concentração de 0,63 x 10-5 mol/l com o LC50= 21,8 mol/l. Com relação ao teste larvicida, os extratos tanto dos frutos de E. passerinum e E. nummularia foram inativos, entretanto a substância 3-metoxi-2,6,12-trihidroxi-15-oxi-10-hidroxi-rianodano apresentou atividade para as larvas de Aedes aegypti causando 100 % de mortalidade na concentração de 2,52 x 10-5mol/l. Todos os extratos foram inativos para o teste de atividade moluscicida, bem como a substância 3-metoxi-2,6,12-trihidroxi-15-oxi-10-hidroxi-rianodano. As substâncias quercetina, epicatequina e quercetina-3-ramnopiranosídeo apresentaram atividade imunomoduladora moderada, embora não tenha sido calculado o IC50. / This work describes the phytochemical study of the chloroform and ethyl acetate extracts of three species of the genus Erythroxylum, E. nummularia, E. passerinum and E. barbatum, besides biological activity assay of crude extracts and pure substances isolatedes in the search of bioactives substances. The genus Erythroxylum belongs to Erythroxylaceae family that comprises approximately 250 species widely distributed in tropical regions and with diversity areas in South America and Madagascar. From the leaves of E. passerinum it was isolated the flavonoids quercetin, quercetin-3-glucopyranoside and epicatechin and from E. nummularia it was obtained 7,4-dimethylquercetin, quercetin, quercetin-3-glucopyranoside and also epicatechin. From the fruits of E. passerinum it was isolated two new ryanodane diterpenes named 3-metoxy-2,6,12-trihydroxy-15-oxy-10-hydroxy-ryanodane and 3,10-dihydroxy-2,6,12-trihydroxy-15-oxy-ryanodane. This is the first report of these diterpenes in the Erytrhoxylaceae family. While E. barbatum lead to the isolation of quercetin-3-rhamnopyranoside, 7,4-dimethylquercetin–rutinoside, quercetin-3-rutinoside, quercetin, epicatechin, besides of -amyrin, -amyrinile palmitate, lupeol, -sitosterol and chlorophyll a. The compounds were isolated through extensive chromatographic procedures and their structures were elucidated by the analyses of 1H RMN and 13C, EM, UV and IR spectral data. The crude extracts and same substances pure were performed cytotoxic, larvicidal, molluscicidal and immunodulator activity assays. In these assay the ethyl acetate of E. passerinum fruits showed 100 % of activity in the A. salina assay at concentration of 100 ppm. This activity is probably due to of the substances 3-metoxy-2,6,12-trihydroxy-15-oxy-10-hydroxy-ryanodane and 3,10-dihydroxy-2,6,12-triidroxy-15-oxy-ryanodane presence. The substance 3-metoxy-2,6,12-trihydroxy-15-oxy-10-hydroxy-ryanodane was toxic in front of A. salina larvae with 50 % death at concentration of 0,63 x 10-5 mol/l with LC50= 21,8 mol/l. In relationship to the larvicidal assay, both extracts of E. passerinum and E. nummularia of the fruits were inactives. However, the substance 3-metoxy-2,6,12-trihydroxy-15-oxy-10-hydroxy-ryanodane showed activity to Aedes aegypti larvae causing 100 % of mortality at concentration of 2,52 x 10-5 mol/l. All the extracts were inactives for the molluscicidal assay, so as, the substances 3-metoxy-2,6,12-trihydroxy-15-oxy-10-hydroxy-ryanodane. The substances quercetin, epicatechin and quercetin-3-rhamnopyranoside showed moderade immunodulator activity, thougt the IC50 was not calculated.

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