Essential oil composition in natural populations of Pistacia lentiscus L. from Tunisia: Effect of ecological factors and incidence on antioxidant and antiacetylcholinesterase activities

Essential oil leaves of 14 Tunisian Pistacia lentiscus L (Anacardiaceae) populations, growing wild in three bioclimatic zones, were analyzed by GC-FID and GC-MS. The species was found to be rich in monoterpene hydrocarbons (41.9%) and sesquiterpene hydrocarbons (40%). alpha-pinene (9.9%), limonene (8.5%), terpinen-4-ol (5.1%), beta-caryophyllene (8.2%), germacrene D (11.9%) and delta-cadinene (8.5%) were found to be the main compounds. Significant variations of essential oil composition, mainly of major compound percentages (alpha-pinene, limonene, terpinen-4-ol, beta-caryophyllene, germacrene D and delta-cadinene), were detected between populations. PCA and CCA analyses showed a substantial chemical differentiation among populations that was mainly attributed to variation of climatic factors (precipitation, Emberger's coefficient, summer precipitation, temperature of the warmest months in the year, evapotranspiration and winter cold stress) and altitude between the analyzed populations. P. lentiscus essential oils were found to possess antioxidant and antiacetylcholinesterase activities. These activities varied significantly among populations. Essential oil of the species collected from the population 1 possessed the highest antiradical (993.4 mu g TE/g EO) and reducing power (13.8 mmol Fe2+/g EO) activities. Essential oil from population 14 exhibited the uppermost capacity to prevent beta-carotene bleaching (IC50 = 557.3 g/ml). The population 13 showed the most important ferrous ion chelating activity (IC50 = 130.6 mu g/ml). Essential oil from the population 6 was found to be the most effective inhibitory against acetylcholinesterase. Levels of antioxidant and antiacetylcholinesterase activities varied according to chemical composition of the investigated essential oils. (C) 2016 Elsevier B.V. All rights reserved.