RESUMO
Chemical composition of the methanol extract of Myrciaria floribunda leaves was investigated. The nor-lupane triterpenoids platanic acid and messagenic I acid were identified, along with other known triterpenoids (betulinic aldehyde, ursolic acid acetate and betulinic acid), a new lupane triterpenoid (2α,6α,30-trihydroxybetulinic acid) and the flavonoids catechin, quercetrin and mirycitrin. The structures were determined by spectroscopic methods (NMR, LC-MS, GC-MS). The major isolated compound was betulinic acid. The methanol extract and 2α,6α,30-trihydroxybetulinic acid were evaluated for their DPPH scavenging potential. The tested triterpenoid was one hundred times more active than betulinic acid, but less active than the extract. Screening for antimicrobial activity showed that the methanol extract was active against Staphylococcus aureus and Escherichia coli, but inactive against Candida albicans and Candida krusei, while 2α,6α,30-trihydroxybetulinic acid was inactive to all tested microorganisms.
Assuntos
Anti-Infecciosos/farmacologia , Antioxidantes/farmacologia , Myrtaceae/química , Extratos Vegetais/química , Triterpenos/farmacologia , Anti-Infecciosos/análise , Anti-Infecciosos/química , Antioxidantes/análise , Antioxidantes/química , Candida albicans/efeitos dos fármacos , Avaliação Pré-Clínica de Medicamentos/métodos , Flavonoides/química , Cromatografia Gasosa-Espectrometria de Massas , Espectroscopia de Ressonância Magnética , Testes de Sensibilidade Microbiana , Estrutura Molecular , Triterpenos Pentacíclicos , Extratos Vegetais/análise , Extratos Vegetais/farmacologia , Folhas de Planta/química , Staphylococcus aureus/efeitos dos fármacos , Triterpenos/análise , Triterpenos/química , Triterpenos/isolamento & purificação , Ácido BetulínicoRESUMO
The phytochemical investigation of Moutabea guianensis roots led to the isolation of five polyoxygenated xanthones, including two new ones named moutabeone B (1,8-dihydroxy-4,5,6,7-tetramethoxyxanthone) and moutabeone C (1-hydroxy-4,5,6,7,8-pentamethoxyxanthone), along with the three known xanthones, 1,8-dihydroxy-4,6-dimethoxyxanthone, 1,8-dihydroxy-4,5,6-trimethoxyxanthone and augustin A (1,8-dihydroxy-4,6,7-trimethoxyxanthone). Structural characterization of all compounds was established on the basis of spectroscopic methods, mainly 1D and 2D nuclear magnetic resonance (NMR) and comparison with literature data. The antioxidant activity of compounds was tested through a thin layer chromatography (TLC) bioautography assay using 1,1-diphenyl-2-picryl-hydrazyl radical (DPPH·) as detection reagent. All tested compounds were more active (DL < 0.13-0.03 µg) than Trolox (DL < 0.15 µg), used as reference standard.
Assuntos
Raízes de Plantas/química , Polygalaceae/química , Xantonas/isolamento & purificação , Cromatografia em Camada Fina , Espectroscopia de Ressonância Magnética , Xantonas/químicaRESUMO
The present work reports the isolation of five compounds from Aspergillus sp EJC08 isolated as endophytic from Bauhinia guianensis, a tipical plant of the Amazon. The compounds ergosterol (1), ergosterol peroxide (2), mevalolactone (3), monomethylsulochrin (4) and trypacidin A (5) were isolated by chromatographic procedures and identified by spectral methods of 1D and 2D NMR and MS. Compounds 3, 4 and 5 were tested against Escherichia coli, Pseudomonas aeruginosa, Bacillus subtilis and Staphylococcus aureus and showed good activity.
