Composition of essential oils and secretory structures of three Baccharis species from Brazil

Essential oils from Baccharis species are widely used for pharmaceutical, flavor and perfumery industries. However, more restricted data are available for B. anomala DC., B. megapotamica Spreng., and B. ochracea Spreng. In that sense, the aim of this work was to investigate the chemical composition of the essential oils and the anatomical structures of the aerial parts from these species growing in Brazil. The volatile constituents isolated by hydrodistillation were analyzed by GC-MSD and GC-FID. The botanical material was fixed, sectioned and prepared according to standard light and scanning microtechniques. The essential oil from B. anomala yielded 0.18% and showed α-acorenol (16.0%), spathulenol (13.3%), and caryophyllene oxide (12.1%) as the main components. Spathulenol (28.0% and 37.1%), and caryophyllene oxide (20.4 and 30.8%) represented the major constituents of the essential oils from B. megapotamica (yield = 0.17%) and B. ochracea (yield = 0.18%), respectively. The leaves and stems of these Baccharis species showed non-glandular trichomes and secretory ducts. Glandular trichomes were also found on the vegetative aerial parts of B. megapotamica. These data support additional information about both chemical composition of the essential oils and morpho-anatomy of Baccharis plants. This study was supported by Fundação Araucária (Brazil).