TY - JOUR T1 - Seasonal variation of the leaf and cone oil of Juniperus excelsa M.B. TT - مطالعه تغییرات فصلی اسانس برگ و مخروط ارس M.B.) (Juniperus excelsa JF - jmpir JO - jmpir VL - 5 IS - 17 UR - http://jmp.ir/article-1-681-en.html Y1 - 2006 SP - 50 EP - 58 KW - Juniperus excelsa KW - Cupressaceae KW - Essential oil composition KW - Seasonal Variation KW - GC-MS N2 - Background: Juniperus excelsa is one of widespread species of the genus Juniperus (Cupressaceae) in Iran, which distributed in all over the country. Objective: The purposes of this study were to determine 1) the volatile oil composition variation of J. excelsa throughout the year and 2) from economically point of view, the best part (leaf or cone) and season for collection and oil extraction. Methods: The volatile constituents of the leaf and cone (berry) of Juniperus excelsa, isolated by steam distillation, were analyzed by GC-MS. Leaf and berry (cone) samples of juniper were collected in spring, summer and autumn from trees growing wild in Iran. Results: Results indicated that the total oil was consisted of almost 25 constituents. Seasonal variation of total oil in cone in contrast with leaf was considerable, so that it increased more than 1.5 time from spring to autumn. Essential oil analysis of the leaves and cones indicated that, α-pinene as the most important constituent of leaf oil was decreased in summer (about 70% in spring, but about 20% in summer), however it was increased in cone oil (about 6% in spring, but about 76% in summer). Conclusion: Total oil in cone but not leaf was increased from spring to autumn. In summer α-pinene the achve constituent of essential oil it was decreased in leaf oil but increased in cone oil. M3 ER -