Abstract
An anatomical evaluation of the secretory structures of Silphium integrifolium and S. trifoliatum rhizomes as well as GC-FID and GC/MS of the essential oil compositions and lipophilic extracts from organs of both species collected in 1999–2001. It was found that sesquiterpene compounds such as α-isocomene, modhephene, 7β-H-silphiperfol-5-ene, β-caryophyllene, β-isocomene, germacrene D, 7α-H-silphiperfol-5-ene, silphiperfol-6-ene and β-bisabolene were the main components of the tested oils and extracts from S. integrifolium and S. trifoliatum. Among the oils and extracts analyzed, signifcant amounts of allo-aromadendr-9-ene as well as α- and β-himachalene were found only in S. integrifolium rhizome oil. The main constituent of lipophilic extracts that was absent in the oils was 16-acetoxycarterochaetol at average content of 39.7±1.0% and 40.5±5.9% in tested extracts