Effect of geographical origin on yield and composition of cone essential oils of Cedrus libani A. Rich. growing in Lebanese protected areas and variability assessment in comparison with literature survey

Gas chromatography-mass spectrometry analysis together with principal component analysis revealed that geographical origin influenced the yield and composition of the essential oils (EOs) extracted by hydrodistillation performed for 3 h using a Clevenger-type apparatus, from the cones of Cedrus libani A. Rich., growing wild at four Lebanese natural reserves and protected areas: Bsharri, Chouf, Ehden, and Tannourine, and from a cultivated cedar growing in Qartaba. Essential oil chemical variability established between the different studied provenances suggested the involvement of abiotic factors such as geographical conditions, cultivation conditions, soil composition, and environmental factors in the chemical polymorphism of C. libani cones EOs. α-Pinene/β-pinene characterized Ehden (β-pinene 35.6%/α-pinene 27.7%), Chouf (α-pinene 37.3%/β-pinene 26.1%), Bsharri (α-pinene 27.7%/β-pinene 21.4%), and Tannourine (α-pinene 25.1%/β-pinene 16.0%) samples, whereas Qartaba EO was distinguished by the dominance of myrcene (30.6%), α-pinene(26%), and limonene (14.1%). Comparison with the existing literature reinforced the chemical variability of C. libani EOs. This current study helped the estimation of a best harvest location for a good EO quality production, resource optimization, and pharmacological properties evaluation, according to the market demand.