GC-MS analysis of the essential oil, aroma components and n-hexane extract of St. John Wort (Hypericum perforatum L., Hypericaceae)

St. John Wort (Hypercum perforatum L., Hypericaceae) has been used as a medicinal plant for a long period of time as this plant is characterized by a diversity of bioactive constituents which possess well documented pharmacological activities including antiviral, antimicrobial, anti-inflammatory, antioxidant, hepatoprotective and anti-tumoral activity. Nowadays, special interest is put on its essential oil as some experimental studies showed great biological and pharmacological potential. According this, the main goal of this study was GC/MS analysis of the essential oil, aroma components as well as n-hexane extracts of Hypericum perforatum that grows in Western region in R. Macedonia. GC/FID/MS analyses of the isolated essential oils from leaf, flower and herb resulted in the identification of 84 compounds. The fraction of sesquiterpenes was dominated in all examined oils and the main constituents were germacrene D (17.77-39.03%), E-caryophyllene (11.37-25.71%) and β-selinene (0.69-4.77%). GC/HS/MS analyses of the aroma components resulted in the identification of 23 compounds. Among them, isononane was identified as main aroma component (up to 75%). GC/FID/MS analyses of the n-hexane extracts resulted in the identification of 60 compounds which were characterized by the presence of terpenoid (mono- and sesquiterpene) components and non-terpenoid constituents mainly consisted of hydrocarbons and their oxygenate derivatives and related components. The non-terpenoid fraction represented the largest part of the analysed extracts. The most abundant were nonacosane (15.45-49.28%), octacosane (1.33-40.05%) and pentacosane (1.68-9.04%). The aerial parts of H. perforatum collected from Western part of R. Macedonia could be considered as a good source of essential oil with specific chemical profile as well as aroma components and high lipophilic compounds, but further investigation should be done in accordance to their possible commercial or medicinal use. Keywords: Hypericum perforatum, essential oil, aroma components, n-hexane extract, GC-MS