Volatile Constituents of Pinus pinea L. Needles

The composition of the essential oil hydro-distilled from needles of Pinus pinea L. trees, collected from six populations coming from Northern Tunisia was determined by GC and GC/MS analysis. Fifty-seven components, accounting for 94.4-99.9% of the oil were identified. As expected, the majority of the identified metabolites were found tube monoterpenes and sesquiterpenes. Monoterpenes account about 76% with 34 of 57 compounds identified. The principal component was limonene (35.9%) followed by alpha-pinene (6.4%). Sesquiterpenes (ca.19%) were mainly beta-cubebene (1.8%), beta-caryophyllene (1.7%), alpha humulene (1.7%) and beta-farnesene (1.7%). Diterpenes (1.4%) were present in few concentrations mainly at one population. Data projection on axes of principal component analysis from pinea samples showed significant geographic polymorphism between Tunisian populations. This suggests that, using an appropriate wide-range sample of P. pinea populations, terpenes could be used to study the genetic diversity of P. pinea. This species has never shown a noticeable genetic variability using microsatellites, fatty acids or allozymes.