Essential oil composition and variability of Hypericum perforatum L. from wild population in Kosovo

Abstract

Aerial parts of Hypericum perforatum L. (Hypericaceae) were collected from five wild populations in Kosovo, with aim to investigate the chemical composition and natural variation of essential oils between wild populations. This species could be considered of economic potential as it is widespread in Kosovo, on the other hand H. perforatum is one of the best-known medicinal herbs used in Kosovo folk medicine. Essential oils were obtained by steam distillation and analysed by GC-FID and GC-MS. Sixty-seven components were identified. The yields of essential oils differed depending on the population and ranged from 0.04 to 0.26% based on dry weight. The aerial parts of H. perforatum were characterized by the following main constituents: 2-methyl-octane (1.1-15.5%), α-pinene (3.7-36.5%), β-caryophyllene (1.2-12.4%), caryophyllene oxide (3.3-17.7%) and n-tetradecanol (3.6- 10.4%). Hierarchical cluster analysis revealed that the concentration of components depends on the origin of the plant populations, thus α-pinene and 2-methyl-octane were present in the highest concentration in population originating from Gjakove, Prizren and Ferizaj, whereas in the populations originating from Peje and Prishtine the most abundant constituents were caryophyllene oxide, β-caryophyllene and n-tetradecanol. Further investigation is needed to establish the natural variability and chemopolymorphism of this species in the territory of Kosovo, which should be supported by molecular level analyses.

Essential Oil of Hypericum perforatum. The chemical composition and antimicrobial activity

“…The studies of H. perforatum Table 1 CHEMICAL COMPOSITION OF THE H. PERFORATUM ESSENTIAL OIL populations originating from Greece [14] and Portugal [15], respectively, showed a higher content of alpha-pinene and beta-pinene than those reported in our study. The wild populations in Kosovo showed a high content of alphapinene along with other major components: 2methyloctane, beta-caryophyllene, germacrene D [12]. In contrast, a Serbian sample [10] showed a different chemical composition, in this study nonane (63.8%) being the most abundant component.…”

“…The extraction yield was 0.41% (v/w) based on the dry plant material. Comparatively, the contents of essential oils from Romania were 0.23% [6], Serbia 0.03-1.93 [25], Portugal 0.15% [15], Turkey 0.04-0.5% [26] and Kosovo 0.04-0.26% [12]. The H. perforatum EO's specific gravity at 25°C was 0.703±0.006 g/cm 3 ; the refractive index at 20°C was 1.431±0.041, respectively.…”

“…Some studies have reported as a major component 2methyloctane [2,11,12,16]; others n-nonane, along with smaller amounts of 2-methyldecane and n-undecane [10,17], αand β-pinene [6,15], or caryophyllene and germacrene [12,16], respectively. These results can be explained by the postulate that the chemical composition of EOs is influenced by genetic and environmental factors, harvesting time, stage of development of the plant and plant part analyzed [11,12,16].…”

Essential oil composition of indigenous populations of Hypericum perforatum L. from southern Albania

“…According to literature data, large variation in EO content (0.04-1.93%) was also reported for plants from six different localities in Serbia [30]. Additionally, the yields of EOs from HP from Kosovo differed greatly depending on the population and ranged from 0.04 to 0.26% based on dry weight [31].…”

“…In the same study, trans-(E)-caryophyllene and caryophyllene oxide were reported to be principal components. In the region of Kosovo, HP were characterized by the following main constituents: α-pinene (3.70-36.50%), 2-methyl-octane (1.10-15.50%), trans-(E)-caryophyllene (1.20-12.40%), caryophyllene oxide (3.30-17.70%) and n-tetradecanol (3.60-10.40%) [31].…”