RESUMO
Chemical characterization of the essential oils of two Lippia species by GC-MS and NMR spectroscopy revealed that limonene (84.3%) and ß-caryophyllene (6.1%) were the most abundant components in Lippia turbinata while (6S,7S,10S)-trans-davanone (99.1%) predominated in Lippia integrifolia. Antifungal activity of the essential oils was determined by headspace volatile exposure assay against the fungal phytopathogenic Sclerotinia sclerotiorum, Sclerotium rolfsii and Rhizoctonia solani. The essential oil of L. turbinata showed potent antifungal activity against the panel of fungi tested while that the oil of L. integrifolia significantly inhibited the mycelial growth of S. rolfsii and R. solani.
La caracterizacioÌn quiÌmica de los aceites esenciales de dos especies de Lippia por cromatografiÌa gaseosa-espectrometriÌa de masas (CG-EM) y espectroscopia de RMN reveloÌ que limoneno (84,3%) y ß-cariofileno (6,1%) fueron los componentes maÌs abundantes de Lippia turbinata mientras que (6S,7S,10S)-trans-davanona (99,1%) predominoÌ en Lippia integrifolia. La actividad antifuÌngica de los aceites esenciales se determinoÌ por el ensayo de exposicioÌn a los vapores frente a los hongos fitopatoÌgenos Sclerotinia sclerotiorum, Sclerotium rolfsii y Rhizoctonia solani. El aceite esencial de L. turbinata mostroÌ una potente actividad antifuÌngica frente al panel de hongos ensayados, mientras que el aceite de L. integrifolia inhibioÌ significativamente el crecimiento micelial de S. rolfsii y R. solani.
Assuntos
Ascomicetos/efeitos dos fármacos , Óleos Voláteis/farmacologia , Lippia/química , Antifúngicos/farmacologia , Rhizoctonia/efeitos dos fármacos , Terpenos/análise , Óleos Voláteis/química , Espectroscopia de Ressonância Magnética , Cromatografia Gasosa-Espectrometria de Massas , Antifúngicos/químicaRESUMO
Analysis of the hydrodistilled essential oil of the aerial parts of Chersodoma argentina Cabrera by GC-MS and NMR spectroscopy revealed that over 80% consisted of monoterpene hydrocarbons such as alpha-thujene, alpha-pinene and beta-pinene. Contact and headspace volatile exposure assays of the essential oil demonstrated antifungal activity against Sclerotinia sclerotiorum, Sclerotium rolfsii and Rhizoctonia solani with the contact assay showing greater activity than the headspace assay. Herbicidal activity was shown by reduced root growth of Allium porrum, Solanum lycopersicon and Sorghum halepense in both assays.
Assuntos
Antifúngicos/farmacologia , Asteraceae/química , Herbicidas/farmacologia , Óleos Voláteis/análise , Óleos Voláteis/farmacologiaRESUMO
Three flavonoids, (2 R,3 R)-5,4'-dihydroxy-3'- O-methyl-7-(gamma,gamma-dimethylallyloxy)dihydroflavonol 1, (2 R,3 R)-5,7,4'-trihydroxy-3'- O-methyl-6-(alpha,alpha-dimethylallyl)dihydroflavonol 2, and (2 R,3 R)-5,7,4'-trihydroxy-6-(alpha,alpha-dimethylallyl)dihydroflavonol 3, together with three known flavonoids ( 4 - 6), were isolated from the aerial parts of PTEROCAULON ALOPECUROIDES. The structures of the compounds were determined by mass and by 1 D and 2 D NMR spectroscopy. Screening of the antibacterial activity of all six compounds was conducted by a disc diffusion test against BACILLUS CEREUS, BACILLUS SUBTILIS, SALMONELLA TYPHIMURIUM and PROTEUS MIRABILIS. The minimum inhibitory concentration (MIC) of the active compounds ( 2, 3, 4, 6) was determined by a microdilution assay. These compounds were active only against both Gram+ bacteria with MIC values < or = 200 microg/mL.