Contribution for the Characterization of Portuguese Fennel Chemotypes

Abstract

Essential oils were obtained from the dried fruit of Foeniculum vulgare Miller subsp. piperitum (Ucria) Coutinho collected from various locations in central Portugal. Gas chromatographic analysis of the oils revealed that the major components, fenchone (6.8–30.8%), methyl chavicol (2.6–36.3%) and (E)-anethole (44.2–74.0%), varied widely. No relationship between component concentrations and fruit ripeness was found. Based on the variation in oil composition between the various taxa, the existence of three chemotypes is proposed.