Submitted by Renata Aline Souza Silva (rassilva@uefs.br) on 2022-09-02T13:46:59Z No. of bitstreams: 1 Tese_Danielle Figuer?do da Silva 2020.pdf: 4372485 bytes, checksum: 32db4e67a732eeca14feacfcb9b83b6c (MD5) Made available in DSpace on 2022-09-02T13:46:59Z (GMT). No. of bitstreams: 1 Tese_Danielle Figuer?do da Silva 2020.pdf: 4372485 bytes, checksum: 32db4e67a732eeca14feacfcb9b83b6c (MD5) Previous issue date: 2020-09-29 Funda??o de Amparo ? Pesquisa do Estado da Bahia - FAPEB Studies corroborate the popular use of species of the genus Polygala, however Polygala boliviensis A.W. Benn (Polygalaceae), found in the semi-arid region of Bahia, has few chemical and pharmacological studies. Thus, this work aimed to conduct a pharmacognostic study and the biological activities of P. boliviensis. The collection of the aerial parts and roots of the species, for the different stages, was performed at the UEFS campus, in Feira de Santana, Bahia. For the isolation of secondary metabolites, methanolic extract was prepared by maceration, followed by partition with hexane, chloroform and ethyl acetate, and successive procedures by column chromatography. The identification of the isolated metabolites was performed by one- and two-dimensional NMR, resulting in the chemical structures of 1,3,5-trihydroxy-2-methoxyxanthone, ?-spinasterol, as well as a coumarin and fatty acid mixture that are in confirmation phase. In the evaluation of biological activity, the coumarins auraptene and polygalen, previously isolated from P. boliviensis, were evaluated by MTT test and in vitro antiplasmodial activity against chloroquine-resistant strain of Plasmodium falciparum (W2), and showed IC50 = 13.46 ? 0.03 ?M and EC50 = 0.171 ? 0.016 for auraptene; and above 100 ?M and 0.164 ? 0.012 for poligalen, resulting in the selectivity index of 78.71 and 609.76, respectively. These coumarins were also subjected to docking-based inverse virtual screening using P. falciparum targets from BraMMT, demonstrating better affinity to purine nulceoside phosphorylase and dihydroorotate dehydrogenase enzymes. We also evaluated the seasonal variation of the chemical composition through the identification and quantification of secondary metabolites by HPLC-DAD; the antioxidant activity, through the DPPH-free radical scavenging test and inhibition of ?-carotene auto-oxidation; and the lethality against Artemia salina. By this method, gallic acid, rutin, poligalen, auraptene, and 7 unknown major peaks were identified, which through UV spectra, are believed to be phenolic acids, flavonoids, xanthones, coumarins, and styrylpyrones. Although there was no seasonal variation in the yield of extracts and chemical profile, there was quantitative variation of metabolites, antioxidant activity and lethality against A. salina. For the anatomical characterization light microscopy was used, analyzing samples included in historesin and stained with toluidine blue, while for histochemistry, the samples were sectioned in cryomicrotome and submitted to different tests. P. boliviensis showed amphistomatic leaves and non-glandular trichomes on the leaves and stems, in addition to lysigenous secretory cavities found in the leaves and responsible for lipid secretion. This study contributes to the chemical characterization of P. boliviensis, as well as to taxonomic delimitations, facilitating the differentiation between morphologically similar species, and corroborating the chemosystematics of the genus Polygala. Added to this, the diversity of the chemical composition and antiplasmodial activity demonstrated by auraptene and poligalen reinforce the phytotherapeutic potential of the species, but as seasonality influences the amount of these and other secondary metabolites, it should be considered, facilitating the determination of the collection period or ideal cultivation conditions, to obtain the metabolites of interest. Estudos corroboram o uso popular de esp?cies do g?nero Polygala, no entanto Polygala boliviensis A.W. Benn (Polygalaceae), encontrada no semi?rido baiano, apresenta poucos estudos qu?micos e farmacol?gicos. Nesse sentido, este trabalho teve como objetivo realizar o estudo farmacogn?stico e das atividades biol?gicas de P. boliviensis. A coleta das partes a?reas e ra?zes da esp?cie, para as diferentes etapas, foi realizada no campus da UEFS, em Feira de Santana, Bahia. Para o isolamento dos metab?litos secund?rios, foi preparado extrato metan?lico por macera??o, seguido de parti??o com hexano, clorof?rmio e acetato de etila, e sucessivos procedimentos por cromatografia em coluna. A identifica??o dos metab?litos isolados foi realizada por RMN uni e bidimensionais, resultando nas estruturas qu?micas da 1,3,5-triidr?xi-2-met?xi-xantona, do ?-espinasterol, al?m de uma cumarina e mistura de ?cido graxo que se encontram em fase de confirma??o. Na avalia??o da atividade biol?gica, as cumarinas aurapteno e poligaleno, isoladas anteriormente de P. boliviensis, foram avaliadas pelo teste de MTT e atividade antiplasmodial in vitro contra cepa cloroquina-resistente de Plasmodium falciparum (W2), e demonstraram CI50 = 13,46 ? 0,03 ?M e CE50 = 0,171 ? 0,016 para aurapteno; e acima de 100 ?M e 0,164 ? 0,012 para poligaleno, resultando no ?ndice de seletividade de 78,71 e 609,76, respectivamente. Essas cumarinas foram tamb?m submetidas ? triagem virtual inversa baseada em docking, utilizando os alvos de P. falciparum do BraMMT, demonstrando melhor afinidade com enzimas purina nulceos?deo fosforilase e diidroorotato desidrogenase. Tamb?m foi realizada a avalia??o da varia??o sazonal da composi??o qu?mica atrav?s da identifica??o e quantifica??o dos metab?litos secund?rios por CLAE-DAD; da atividade antioxidante, atrav?s do teste de sequestro do radical livre DPPH? e inibi??o da auto oxida??o do ?-caroteno; e da letalidade frente ? Artemia salina. Por esse m?todo, foram identificados ?cido g?lico, rutina, poligaleno, aurapteno e 7 picos majorit?rios desconhecidos, que atrav?s de espectros no UV, acredita-se tratar de ?cidos fen?licos, flavonoides, xantonas, cumarinas e estirilpironas. Apesar de n?o haver varia??o sazonal no rendimento dos extratos e no perfil qu?mico, houve varia??o quantitativa dos metab?litos, da atividade antioxidante e letalidade frente ? A. salina. Para a caracteriza??o anat?mica foi utilizada microscopia de luz, analizando amostras inclu?das em historesina e coradas com azul de toluidina, enquanto para a histoqu?mica, as amostras foram seccionadas em criomicr?tomo e submetidas a diferentes testes. P. boliviensis apresentou folhas anfiestom?ticas e tricomas n?o glandulares nas folhas e caules, al?m de cavidades secretoras lis?genas encontradas nas folhas e respons?veis pela secre??o de lip?dios. O presente estudo contribui com a caracteriza??o qu?mica da P. boliviensis, bem como para delimita??es taxon?micas, facilitando a diferencia??o entre esp?cies morfologicamente semelhantes, al?m de corroborar com a quimiossistem?tica do g?nero Polygala. Somado a isso, a diversidade da composi??o qu?mica e atividade antiplasmodial demonstrada pelo aurapteno e poligaleno refor?am o potencial fitoterap?utico da esp?cie, por?m como a sazonalidade influencia na quantidade desses e de outros metab?litos secund?rios, deve ser considerada, facilitando a determina??o do per?odo de coleta ou condi??es de cultivo ideais, para obten??o dos metab?litos de interesse.