RESUMO
The methanol extract of the underground part of Rhodiola rosea was found to show inhibitory activity against Staphylococcus aureus. Bioactivity-guided fractionation of a 95% ethanol extract from the stems of R. rosea led to the isolation of five compounds: gossypetin-7-O-L-rhamnopyranoside (1), rhodioflavonoside (2), gallic acid (3), trans-p-hydroxycinnamic acid (4) and p-tyrosol (5). Their structures were elucidated by UV, IR, MS and NMR data, as well as by comparison with those of the literature. Compounds 1 and 2 were evaluated for their antibacterial and antiprostate cancer cell activities. Compounds 1 and 2 exhibited activity against Staphylococcus aureus with minimum inhibitory concentrations of 50 microg/mL and 100 microg/mL, respectively. Cytotoxicity studies of 1 and 2 also displayed activity against the prostate cancer cell line with IC(50) values of 50 microg/mL and 80 microg/mL, respectively.
Assuntos
Antibacterianos/farmacologia , Antineoplásicos Fitogênicos/farmacologia , Fitoterapia , Extratos Vegetais/farmacologia , Rhodiola , Staphylococcus aureus/efeitos dos fármacos , Antibacterianos/administração & dosagem , Antibacterianos/uso terapêutico , Antineoplásicos Fitogênicos/administração & dosagem , Antineoplásicos Fitogênicos/uso terapêutico , Linhagem Celular Tumoral , Humanos , Concentração Inibidora 50 , Testes de Sensibilidade Microbiana , Extratos Vegetais/administração & dosagem , Extratos Vegetais/uso terapêutico , Raízes de Plantas , Caules de PlantaRESUMO
Activity-guided fractionation of the 95% ethanol extract from the stem bark of Iryanthera megistophylla led to the isolation of two new compounds, named megislignan [2,3-dimethyl-4-(4-methoxyphenyl)-6-hydroxynaphthalene] (1) and megislactone [(2R,3R,4R)-3-hydroxy-4-methyl-2-(hexacos-17-enyl)butanolide] (2), along with seven known compounds, grandinolide (3), iryantherin K (4), iryantherin L (5), cinchonain I b (6), cinchonain I a (7), procyanidin B-2 (8), and cinchonain IIa (9). The structures of the new compounds were elucidated by spectral data interpretation. Isolates were evaluated for their antibacterial, antifungal, antiviral, and antiacetylcholinesterase activities.