Chemical composition and antibacterial activity of Juniperus thurifera L. essential oils

The qualitative and quantitative composition of the essential oils obtained from male and female leaves of Juniperus thurifera L., (growing in Algeria) has been investigated for the first time. The essential oils were obtained by hydrodistillation (0.45% from female trees and 0.53% from male trees, v/w dried material) and analyzed by gas choromatography (GC) and gas choromatography-mass spectrometery (GC-MS). Seventy-seven compounds were identified, representing more than 97% of the oils. The major components were Sabinene, α-pinene and terpinene-4-ol. The concentrations of the oil constituents: α-thujene, α-pinene, α-phellandrene, p-cymene, linalyl acetate, Δ-amorphene, germacrene D-4-ol, and 4-epi-abietal were greater in the oil of the female tree than in the oil of the male tree. Conversely, the concentrations of α-terpinene, γ-terpinene, terpinene-4-ol, elemol, α-epi-cadinol and α-eudesmol were greater in the oil of the male tree than in the oil of the female tree. However, the concentration gradient trends for both female and male trees were similar for sabinene, myrcene, linalool, β-pinene, limonene, cis-sabinene hydrate terpinolene, α-terpineol. The antimicrobial activity of male and female J. thurifera essential oils was evaluated against 14 bacteria. The results showed a variable degree of antibacterial activity depending from the type of the oil (extracted from male or female trees). Essential oils of female trees were most effective.