The chemical composition of the essential oil of Hypericum hirsutum L. from Suva planina (SE Serbia)

Abstract

The genus Hypericum (family Hypericaceae) includes over 500 species with a nearly worldwide distribution, missing only from tropical lowlands, deserts, and polar regions. Hypericum hirsutum L., known as Hairy St. John's wort, is very similar to the main representative of genus Hypericum - Hypericum perforatum L. (St. John’s wort). Hypericum hirsutum has the typical St. John's wort flower about half an inch or more across and a pale yellow color; blunt, oval, translucent-dotted leaves about 2.5-5 cm long on a smooth, hairy and generally unbranched stem up to about 30-60 cm tall. This perennial species is widely distributed throughout Europe (except the Mediterranean region), northwestern Africa, China and southwestern Asia [1].

                Herein, we analyzed by GC-MS the composition of the hydrodistilled essential oil from the aboveground parts of H. hirsutum, leaves and stems, and brown capsules (with seeds) at the fruiting stage, separately. The yield of both essential-oil samples was rather low (0.038%, and 0.055%, for leaves and stems, and capsules, respectively), based on the weight of air-dried plant material collected from Suva planina, a mountain in southeastern Serbia. The GC-MS analysis allowed the identification of 90 components in the essential oil of the leaves and stems, and 45 components from the essential oil of the capsules, representing ca. 90% of the total GC-peak areas detected (for both samples). The main components of the leaf essential oil were: n-nonane (16.8%), n-undecane (10.1%), (E)-β-farnesene (9.3), caryophyllene oxide (5.0%), spathulenol (4.5%), (E,E)-α-farnesene (4.0%), δ-cadinene (3.5%), (E)-caryophyllene (3.2%), germacrene D (3.0%), and (E)-β-ocimene (2.1%); and the main components in the essential-oil sample from the capsules were: alloaromadendrene (11.5%), caryophyllene oxide (11.1%), n-undecane (7.6%), (E)-caryophyllene (6.1%),
γ-humulene (5.8%), δ-cadinene (5.6%), α-longipinene (5.4%), α-bisabolol (3.6%), and n-nonane (3.3%).