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.
Hypericum perforatum is well known for its antidepressant and anti-inflammatory activities, for which hypericin and its derivatives are indicated to be the most active compounds. Hypericin synthase (Hyp-1) is the only protein proven to catalyze the synthesis of hypericin. In this study, the full-length cDNA of Hyp-1 was chemically synthesized according to the Hyp-1 sequence in GenBank (accession no. AY148090) and then cloned into the plasmid pET22b. Hyp-1 was expressed in Escherichia coli BL21 (DE3) and purified with a Ni-NTA column. The purified protein was used to immunize New Zealand white rabbits, from which an antiserum was purified by protein G affinity chromatography. The polyclonal antibody against Hyp-1 provides a valuable tool for the study of hypericin biosynthesis in H. perforatum. Expression of Hyp-1 and the cellular distribution of hypericin were analyzed in different organs of red-pigmented H. perforatum plantlets. The black glands were not the only site of hypericin accumulation and the results indicated that hypericin might be synthesized in mesophyll cells or in tissues of the root and/or stem and then transported to the glands. This work provides a foundation for further investigation of the regulatory mechanism of hypericin synthesis during the development of H. perforatum.
JavaScript is turned off in your web browser. Turn it on to take full advantage of this site, then refresh the page.