Characterization of some metabolites in the needles of Common Juniper (Juniperus communis L.) from Lithuania

Abstract

Common juniper (Juniperus communis L.) is representative of Cupressaceae, existing in the forms of the shrub or tree within very broad ecological scale. Juniper is known as a plant that is rich in secondary substances, particularly terpenoids and phenolic compounds. It’s essential oils are widely used in pharmaceutical and technical preparations, cosmetic products and as a food additive. Our study aimed at evaluation of genetic diversity of juniper, relating metabolites with molecular parameters and habitat type. In September, 2013, 140 female individuals were sampled from 14 Lithuanian populations of common juniper. Current-year needles were taken from the middle part of the crown and dry material was prepared for biochemical analysis. Samples were analysed according to the protocol, described earlier [1]. Both terpenoids and soluble phenolic compounds were analysed. Terpenoids were isolated and characterized using gas chromatography (GC) with an HP-5 column 30 m x 320 μm x 0.25 μm (Agilent Technologies, Santa Clara, CA). Soluble phenolics were analysed using high performance liquid chromatography (Nexera2, LC-DAD-MS, Shimadzu) and column ODS2, 250 x 4.6 mm. Quantification of the major terpenoids and flavonoids showed very high variability of concentration in respect to different populations. In the current-year needles absolute values of ranged for terpenoids from 2.50 to 5.02 (mg/g d. m.) and for flavonoids from 3.05 to 8.18 (mg/g d.m.), respectively. These results allowed to compare secondary metabolites of the needles of populations belonging to different habitat type. Our data suggest that composition and quantity of secondary metabolites of common juniper are related to the habitat type.