Constituintes qu?micos e a atividade biol?gica de Eupatorium macrocephalum Less. (Aster?cea) e Annona dioica ST Hill. (Annon?ceae): uma contribui??o ao estudo de plantas medicinais no Paraguay

• Autor(a) principal: Vega, Maria Raquel Garcia
• Data de Publicação: 2007
• Tipo de documento: Tese
• Idioma: por
• Título da fonte: Biblioteca Digital de Teses e Dissertações da UFRRJ
• Texto Completo: https://tede.ufrrj.br/jspui/handle/tede/34
• topic: plantas medicinais; atividade biol?gica; Eupatorium macrocephalum; Annona di?ica; terpen?ides; flavon?ides; Qu?mica

Eupatorium macrocephalum Less (Asteraceae) and Annona dioica (Annonaceae) are distributed throughout South America and have long been used as paraguayan folk medicine. The present work relates the chemical investigation of the extracts of Eupatorium macrocephalum Less (colleted in Dpto. Central-Paraguay) which resulted in the isolation and identification of twenty compounds: six triterpenoids; lupeol and lupeol acetate (the main chemical components), taraxasterol and taraxasterol acetate together with a- and b-amiryn; six steroids; stigmasterol, sitosterol, epinasterol, 3-O-b- D-glicopyranosylstigmasterol, 3-O-b-D-glicopyranosylepinasterol and 3-O-b-Dglicopyranosylsitosterol; one diterpenoid, -9,15-diidroxikauren-3-O-b-D-glicopiranosyl; one flavonoid, 3 ,4 ,5-triidroxi-6,7-dimetoxiflavone and six ?c. cynnamyc derivates. The methanolic extract from the leaves of Annona dioica specimens collected in the cerrado of Horqueta city (Dpto. Concepci?n-Paraguay) led to the isolation and identification of nine compounds: four flavonoids: kaempferol, 3-O-[3 ,6 -di-O-phydroxycynnamoyl]- b-galactopyranosyl-kaempferol, 6 -O-p-hydroxycinnamoil-b- galactopyranosyl-kaempferol and 3-O-b-galactopyranosyl-kaempferol. Three steroids, sitosterol, stigmasterol and 3-O-b-D-glicopyranosylsitosterol.The CHCl3 extract from the root furnished two acetogenines, one known as motrilin and a new isomer epimotriline. The structures were established using. IV, Mass and NMR spectral data, including 2D NMR experiments of natural substances or by the comparison of spectral and physical data with those described in the literature. Biological tests using the brine shrimp lethality test in Artemia salina Leach for screening with all extract revealed good activity so for A. dioica extracts. The cytotoxic effects of the flavonoids and flavonoidic fractions (FF) were evaluated by MTT (3-(4,5- dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay against Ehrlich carcinoma cells. The inhibitory action on DNA-topoisomerase I and II of all the flavonoids was evaluated by relaxation assays on pBR322 plasmid DNA. The obtained fractions of the metanolic extract of the roots were submitted the screening of activity antitumoral in vitro in lineages of cells human tumorais [MDAMB435, HCT8, HL60 and SF295]. The results showed activity of all of the fractions tested in at least one of the lineages used in the screening.