Aspectos metabolômico, biológico e proteômico de Maytenus ilicifolia e Salacia campestris (Celastraceae)
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Data
2010-08-23
Autores
Santos, Vânia Aparecida de Freitas Formenton Macedo dos [UNESP]
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Universidade Estadual Paulista (Unesp)
Resumo
Este projeto teve como principal objetivo o estudo de aspectos químicos, biológicos e biossintéticos dos metabólitos secundários de duas espécies de Celastraceae, Maytenus ilicifolia e Salacia campestris. O estudo fitoquímico das cascas das raízes das duas espécies selecionadas resultou no isolamento de oito substâncias pertencentes a três diferentes classes de metabólitos secundários, incluindo os triterpenos quinonametídeos, maitenina e pristimerina; os alcalóides piridínicos sesquiterpênicos, aquifoliunina E1, maiteina, wilforina, sendo dois inéditos, maiteinol e campestrina; além de uma catequina, ourateacatequina. Os extratos, frações e substâncias puras foram avaliados quanto a atividade antifúngica, frente aos patógenos humanos Candida albicans, C. kruseii, C. parapsilosis e Cryptococcus neoformans; tripanocida, frente a cepa Y da forma epimastigota do Trypanossoma cruzi; leishmanicida, frente a formas promastigotas de L. amazonensis e L. chagasis e antitumoral avaliado por testes de viabilidade metabólica usando três tipos de células tumorais, incluindo B16 (melanoma), HeLA (colo uterino) e U343 (astrocitoma cerebral). Em todas as matrizes biológicas avaliadas, os triterpenos quinonametídeos, maitenina e pristimerina, se mostraram os mais potentes, evidenciando atividade biológica superior aos controles positivos utilizados. Além dos triterpenos quinonametídicos, os alcalóides piridínicos sesquiterpênicos, aquifoliunina E1 e maiteinol se mostraram ativos nos testes leishmanicida e tripanocida, respectivamente, mas menos potentes que os triterpenos quinonametídeos. Experimentos para avaliar a biossíntese das etapas de oxidação que ocorrem no anel E dos triperpenos quinonametídeos foram baseados em protocolos para a extração da enzima oxidoredutase do tipo citocromo P450, supostamente envolvida nas referidas etapas de oxidação...
The project was addressed to investigate chemical, biological and biosynthetic aspects of major secondary metabolites from two Celastraceae species, Maytenus ilicifolia (espinheira-Santa) and Salacia campestris. The phytochemical study of the bark roots resulted in the isolation of eight compounds belonging to three different classes of natural products including the quinonemethides triterpenes, maytenin and pristimerin; the alkaloids pyridine sesquiterpenes, aquifoliunine E1, mayteine, wilforine, including two novel, mayteinol and campestrine; in addition to one catechin, ourateacatechin. The localization of quinonemethides triterpenes in roots of M. ilicifolia was achieved by histochemical analysis based on complexation reactions using some specific reagents to identify groups or organic functions in the interested molecule. The crude extracts, fractions and pure compounds had their antifungal properties assayed against the human pathogens Candida albicans, C. kruseii, C. parapsilosis and Cryptococcus neoformans. Additionally, their anti-parasite activity were assessed against Trypanossoma cruzi (epimastigote form of Y strain), L. amazonensis and L. chagasis (promastigote forms) while the antitumoral activity was based on metabolic viability metabolic using two kinds of tumor cells, B16 (melanoma), HeLA (uterus) e U343 (cerebral astrocytoma). The quinonemethides triterpenes, maytenin and pristimerin displayed considerable potential since were more active than controls. The alkaloids pyridine sesquiterpenes, aquifoliunine E1 and mayteinol revealed to have some potential as leishmanicidal and trypanocide, respectively, but not comparable to quinonemethides triterpenes. As the biosynthesis of quinonemethides triterpenes is concerned, the oxidation step at ring E was investigated considering the participation of cytochrome P450 oxidoreductase besides enzymatic assays using pristimerin... (Complete abstract click electronic access below)
The project was addressed to investigate chemical, biological and biosynthetic aspects of major secondary metabolites from two Celastraceae species, Maytenus ilicifolia (espinheira-Santa) and Salacia campestris. The phytochemical study of the bark roots resulted in the isolation of eight compounds belonging to three different classes of natural products including the quinonemethides triterpenes, maytenin and pristimerin; the alkaloids pyridine sesquiterpenes, aquifoliunine E1, mayteine, wilforine, including two novel, mayteinol and campestrine; in addition to one catechin, ourateacatechin. The localization of quinonemethides triterpenes in roots of M. ilicifolia was achieved by histochemical analysis based on complexation reactions using some specific reagents to identify groups or organic functions in the interested molecule. The crude extracts, fractions and pure compounds had their antifungal properties assayed against the human pathogens Candida albicans, C. kruseii, C. parapsilosis and Cryptococcus neoformans. Additionally, their anti-parasite activity were assessed against Trypanossoma cruzi (epimastigote form of Y strain), L. amazonensis and L. chagasis (promastigote forms) while the antitumoral activity was based on metabolic viability metabolic using two kinds of tumor cells, B16 (melanoma), HeLA (uterus) e U343 (cerebral astrocytoma). The quinonemethides triterpenes, maytenin and pristimerin displayed considerable potential since were more active than controls. The alkaloids pyridine sesquiterpenes, aquifoliunine E1 and mayteinol revealed to have some potential as leishmanicidal and trypanocide, respectively, but not comparable to quinonemethides triterpenes. As the biosynthesis of quinonemethides triterpenes is concerned, the oxidation step at ring E was investigated considering the participation of cytochrome P450 oxidoreductase besides enzymatic assays using pristimerin... (Complete abstract click electronic access below)
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Quimica organica, Organic Chemistry
Como citar
SANTOS, Vânia Aparecida de Freitas Formenton Macedo dos. Aspectos metabolômico, biológico e proteômico de Maytenus ilicifolia e Salacia campestris (Celastraceae). 2010. 263 f. Tese (doutorado) - Universidade Estadual Paulista, Instituto de Química de Araraquara, 2010.