RESUMO
Adenanthera pavonina is a plant belonging to family Fabaceae. The 95% ethanol extract (EtOH) of the dried powdered leaves of the plant and successive extracts with solvents of increasing polarities were prepared. Fractionation of the successive aqueous EtOH extract on polyamide column and purification of the isolated compounds on Sephadex LH20 led to the isolation of a new methoxy flavonol glycoside named as quercetin 3-O-α-dirhamnopyranosyl-(1â´ â 2â³,1â³â³ â 6â³)-ß-glucopyranoside-4'-methoxy (1), as well as kaempferol-3-O-α-dirhamnopyranosyl-(1â´ â 2â³,1â³â³ â 6â³)-ß-glucopyranoside (2), isovitexin (3), quercetin-3-O-rhamnopyranosyl(1â´ â 4â³)-ß-glucopyranoside (4), quercetin-3-O-ß-glucopranoside-4'-O-rhamnopyranoside (5), kaempferol-3-O-α-rhamnopyranosyl(1â´ â 2â³)-ß-glucopyranoside (6), quercetin-3-O-rhamnopyranosyl(1â´ â 2â³)-ß-glucopyranoside (7), quercetin-3-O-ß-glucopyranoside (8), kaempferol (9) and quercetin (10). Structures of the isolated compounds were established by spectroscopic analysis. Antioxidant activities of EtOH extract, successive extracts and compounds 1 and 2 were evaluated. The ethyl acetate (EtOAc) extract and EtOH extract showed 62.67% and 49.30% free radical scavenging activity, respectively. Cytotoxic activities of the EtOH extract and compounds (1) and (2) were evaluated. The EtOH extract showed a significant cytotoxic activity against Hep G-2 (IC50 = 2.50 µg) as compared with cisplatin (IC50>10 µg).
Assuntos
Antineoplásicos Fitogênicos/isolamento & purificação , Antineoplásicos Fitogênicos/farmacologia , Antioxidantes/isolamento & purificação , Antioxidantes/farmacologia , Fabaceae/química , Flavonóis/isolamento & purificação , Flavonóis/farmacologia , Sequestradores de Radicais Livres/isolamento & purificação , Sequestradores de Radicais Livres/farmacologia , Glicosídeos/isolamento & purificação , Glicosídeos/farmacologia , Quercetina/análogos & derivados , Antineoplásicos Fitogênicos/química , Antioxidantes/química , Cisplatino/farmacologia , Ensaios de Seleção de Medicamentos Antitumorais , Egito , Flavonoides/química , Flavonoides/isolamento & purificação , Flavonóis/química , Sequestradores de Radicais Livres/química , Glucosídeos/química , Glucosídeos/isolamento & purificação , Glicosídeos/química , Células Hep G2 , Humanos , Quempferóis/química , Quempferóis/isolamento & purificação , Folhas de Planta/química , Quercetina/química , Quercetina/isolamento & purificação , Quercetina/farmacologia , EstereoisomerismoRESUMO
The effect of drying intact clippings of Taxus on the recovery of taxol and related compounds was studied under different drying conditions which included tobacco drying barn, greenhouse, shadehouse, air conditioned laboratory, oven, and freeze-drying. For clippings dried under tobacco barn, greenhouse, oven, and freeze-drying conditions, nearly total recovery of the expected levels based upon projections from analysis of fresh biomass was observed for taxol and cephalomannine. However, only 75-80% of the expected values for 10-deacetyltaxol and 10-deacetylbaccatin III were found. When the length of drying was extended up to 10 and 15 days as in the shadehouse and laboratory conditions, the recovery of all taxanes was adversely affected.
