Chemical composition of Hypericum rumeliacum Boiss. essential oil. A new chemotype of this pharmacologically valuable species?
Analysis by GC and GC/MS of the essential-oil samples obtained from dry above-ground parts of Hypericum rumeliacum Boiss. (collected in the flowering and fruit-forming vegetative stages) allowed the identification of 212 components in total, comprising ≥97.8% of the total oil composition. In the flowering phase, the major identified volatile compounds were undecane (6.6%), dodecanal (10.8%), and germacrene D (14.1%), whereas α-pinene (7.3%), β-pinene (26.1%), (Z)-β-ocimene (8.5%), (E)-β-ocimene (10.2%), bicyclogermacrene (7.7%), and germacrene D (15.1%) were dominant in the fruit-forming phase. Some of the minor constituents found in the studied oil samples (e.g., a homologous series of four 6-alkyl-5,6-dihydro-2H-pyran-2-ones, i.e., massoia dodeca-, trideca-, tetradeca-, and hexadecalactones) have a restricted occurrence in the Plant Kingdom, and their presence in Hypericum L. spp. has not been previously reported. The chemical compositions of the herein studied additional 34 oils obtained from selected Hypericum taxa were compared using multivariate statistical analysis (agglomerative hierarchical cluster analysis and principal component analysis). The results of these statistical analyses could not be used to either confirm or discard the existence of different H. rumeliacum chemotypes. However, they have implied that the volatile profile of this plant species is determined by the stage of its phenological development.
Department of Chemistry, Faculty of Science and Mathematics, University of Niš, Višegradska 33, RS-18000 Niš Serbia. nikoradulovic@yahoo.com
Niko S
NS
Radulović
Polina D
PD
Blagojević
D016000:Cluster Analysis; D008401:Gas Chromatography-Mass Spectrometry; D020902:Hypericum / Q000737:chemistry*; D015999:Multivariate Analysis; D009822:Oils, Volatile / Q000737:chemistry*; D035261:Plant Components, Aerial / Q000737:chemistry; D025341:Principal Component Analysis
D009822:Oils, Volatile