RESUMO
Two sample preparation methods, namely hydrodistillation (HD) and solvent-assisted flavor evaporation (SAFE), have been used to investigate the essential oils of the aerial parts (leaves and stems) of Symplocarpus foetidus, a plant with a characteristic odor, by gas chromatography mass spectrometry (GC-MS). Characteristic aroma-active compounds in the oils were detected by GC-Olfactometry (GC-O) and aroma extract dilution analysis (AEDA). From the HD method, the main compounds in the oil were found to be p-vinyl-guaiacol (15.5%), 2-pentyl-furan (13.4%), and (Z)-ligustilide (9.5%). From the SAFE method, the main compounds were 2-butoxy-ethanol (49.6%), ethyl-pentanoate (4.5%), and mesitylene (4.0%). In HD oil, the most intense aroma-active compounds were 2-pentyl-furan (flavor dilution factor (FD) = 32, odor activity value (OAV) = 57), p-vinyl-guaiacol (FD = 16, OAV = 41), and dimethyl disulfide (FD = 16, OAV = 41). In SAFE oil, the main aroma-active compounds were 2-butoxy ethanol (FD = 32, OAV = 16), and 2-methoxy thiazole (FD = 32, OAV = 25).
Assuntos
Araceae/química , Odorantes/análise , Óleos Voláteis/química , Óleos de Plantas/química , 4-Butirolactona/análogos & derivados , 4-Butirolactona/análise , 4-Butirolactona/isolamento & purificação , Derivados de Benzeno/análise , Derivados de Benzeno/isolamento & purificação , Destilação/métodos , Dissulfetos/análise , Dissulfetos/isolamento & purificação , Etilenoglicóis/análise , Etilenoglicóis/isolamento & purificação , Furanos/análise , Furanos/isolamento & purificação , Cromatografia Gasosa-Espectrometria de Massas , Guaiacol/análise , Guaiacol/isolamento & purificação , Técnicas de Diluição do Indicador , Óleos Voláteis/isolamento & purificação , Olfatometria/métodos , Folhas de Planta/química , Óleos de Plantas/isolamento & purificação , Caules de Planta/química , Valeratos/análise , Valeratos/isolamento & purificação , VolatilizaçãoRESUMO
One new pentacyclic triterpenoid psidiumoic acid (5) along with four known compounds beta-sitosterol (1), obtusol (2), oleanolic acid (3), and ursolic acid (4) have been isolated from the leaves of Psidium guajava. The new constituent 5 has been characterized as 2 alpha-glycolyl-3beta-hydroxyolean-12-en-28-oic acid through 2D NMR techniques. This is the first report of isolation of compound 2 from the genus Psidium.