Composition and Chemical Variability of the Cone Oil from Algerian Tetraclinis articulata.

Very little is known about the yield and chemical composition of the essential oil isolated from cones of Tetraclinis articulata (Vahl) Masters (Cupressaceae). In continuation of our on-going work devoted to the valorisation of medicinal and aromatic plants from Tlemcen Province (North-Western Algeria), cones have. been harvested in eight locations (coastal township and highlands) and 40 oil samples have been isolated by hydrodistillation. Six oil samples were analyzed by a combination of chromatographic [GC(Retention indices)] and spectroscopic techniques (GC-MS, "C NMR). Then, the remaining 34 oil samples. were analyzed by [GC(RI)] and 13C NMR and the 40 compositions were submitted to statistical analysis. Essential oil yields varied substantially from sample to sample (0.17 to 1.13%, w/w). The cone oils consisted mainly of monoterpenes, with α-pinene (47.1-73.6%) and limonene (6.5-21.9%) being the main components. (E)--Caryophyllene and germacrene D were the major sesquiterpenes. Diterpenes, (Z) and (E)-biformene were identified for the first time-in T. articulata essential oil. PCA analysis of the data allowed the distinction of two groups, the second group being sub-divided into two sub-groups. Groups and sub-groups were differentiated with respect to their contents of a-pinene and limonene and, to a lesser extent, of sesquiterpenes.