The intrasectional chemotaxonomic placement of Hypericum elegans Stephan ex Willd. Inferred from the essential-oil chemical composition.

Here we report, for the first time, the results of detailed GC and GC/MS analyses of the essential oil of a rare taxon in Serbia, Hypericum elegans Stephan ex Willd. One hundred and sixty two constituents identified accounted for 98.6% of the oil. The major components of the oil were undecane (31.9%), alpha-pinene (16.7%), nonane (6.1%), bicyclogermacrene (5.8%), 2-methyloctane (3.7%), and germacrene D (3.6%). Non-terpenoids as chemotaxonomic markers constituted the main fraction of H. elegans oil, whereby n-alkanes were the most abundant contributors of this fraction. Based on these results and previously published ones, we performed an intrasectional multivariate statistical comparison of corresponding essential-oil chemical compositions. Principal component analysis (PCA) and agglomerative hierarchical clustering (AHC) of the data on the volatile profiles of section Hypericum taxa revealed that H. elegans either represents an oil chemotype of its own (AHC) or could be considered related to H. perforatum (PCA).