VOLATILE SECONDARY METABOLITES FROM SPILANTHES AMERICANA OBTAINED BY SIMULTANEOUS STEAM DISTILLATION SOLVENT-EXTRACTION AND SUPERCRITICAL-FLUID EXTRACTION

Citation
Ee. Stashenko et al., VOLATILE SECONDARY METABOLITES FROM SPILANTHES AMERICANA OBTAINED BY SIMULTANEOUS STEAM DISTILLATION SOLVENT-EXTRACTION AND SUPERCRITICAL-FLUID EXTRACTION, Journal of chromatography, 752(1-2), 1996, pp. 223-232
Citations number
15
Categorie Soggetti
Chemistry Analytical","Biochemical Research Methods
Journal title
Volume
752
Issue
1-2
Year of publication
1996
Pages
223 - 232
Database
ISI
SICI code
Abstract
Secondary volatile metabolites were isolated by simultaneous distillat ion-solvent extraction (SDE) and supercritical (CO2) extraction (SFE) from flowers, leaves and stems of Spilanthes americana (Mutis) Hieron (Compositae). The extracts were analyzed by capillary gas chromatograp hy using flame ionization, nitrogen-phosphorus (NPD) or mass spectrome tric detection. Compounds were identified according to their Kovats in dexes, mass spectra (EI, 70 eV), or by comparison with standard substa nces. The method of extraction (SDE, SFE) and the source of the plant material (flowers, stems, leaves) affected the composition of the extr acts. SFE extracts from stems were rich (>40%) in sesquiterpenes (alph a- and beta-bisabolenes, caryophyllene and cadinenes), while those fro m leaves and flowers were abundant in nitrogenated (43 and 27%) and ox ygenated (36 and 23%) compounds. N-(isobutyl)-2E,6Z,8E-decatrienamide, N-(2-methylbutyl)-2E,6Z,8E-decatrienamide, N-(isobutyl)-6Z,8E-decadie namide and N-(2-phenylethyl)-2E,6Z,8E-decatrienamide are examples of t he nitrogenated compounds found. SDE extracts from stems, leaves, and flowers of S. americana contained sesquiterpene levels of 32, 28 and 2 0%, and a generally higher proportion of oxygenated compounds (28, 52 and 32%) and monoterpenes (27, 10 and 42%) than their SFE counterparts . Only trace-level contents of nitrogenated compounds were found using NPD in SDE extracts. Some heavy hydrocarbons (C-n>20) originated from flower pigments and waxes were isolated by SFE but not by SDE. SFE wa s both selective and highly efficient in the isolation of sesquiterpen es, heavy hydrocarbons and nitrogenated compounds (amides).