Kamkar Jaimand - Phytochemistry Group, Department of Medicinal Plants & By-products, Research Institute of Forest and Rangelands, P.O.Box ۱۳۱۸, Tehran, Iran
Mohammad-Bagher Rezaee - Phytochemistry Group, Department of Medicinal Plants & By-products, Research Institute of Forest and Rangelands, P.O.Box ۱۳۱۸, Tehran, Iran
Mahmood Naderi - Phytochemistry Group, Department of Medicinal Plants & By-products, Research Institute of Forest and Rangelands, P.O.Box ۱۳۱۸, Tehran, Iran
Valiollah Mozaffrian - Phytochemistry Group, Department of Medicinal Plants & By-products, Research Institute of Forest and Rangelands, P.O.Box ۱۳۱۸, Tehran, Iran
Rahman Azadi - Phytochemistry Group, Department of Medicinal Plants & By-products, Research Institute of Forest and Rangelands, P.O.Box ۱۳۱۸, Tehran, Iran
Shahrokh Karimi - Phytochemistry Group, Department of Medicinal Plants & By-products, Research Institute of Forest and Rangelands, P.O.Box ۱۳۱۸, Tehran, Iran
Mostafa Gholipoor - Phytochemistry Group, Department of Medicinal Plants & By-products, Research Institute of Forest and Rangelands, P.O.Box ۱۳۱۸, Tehran, Iran

The genus Hypericum is one of the most important medicinal plants that contain ۱۷ species in Iran, three of them are endemics. This paper reports the essential oil composition of six Hypericum species from Iran. The essential oil analysis of a number of the studied plants has already been reported but their report from Iran may be valuable for scientists.  Samples collected between June and August ۲۰۰۷. The composition of the essential oils from Hypericum was investigated on flower and leaf. Essential oils were obtained by hydrodistillation method and then were analyzed by GC and GC/MS. Main components obtained in H. dogonbadanicum (endemic of Iran)  on flower were phenyl ethyl octanoate(۲۹.۰%), terpin-۴-ol (۲۰.۰%), and a-phellandrene (۱۲.۹%), and on leaf were b-pinene (۵۴.۳%), a-pinene (۱۲.۰%) and p-cymene (۱۱.۰%), in H. helianthemoides  on flower were a-pinene (۵۵.۹%), Z-b-ocimene (۸.۷%) and b-pinene (۷.۵%), and in H. hyssopifolium on flower were a-pinene (۴۹.۵%), b-pinene (۱۲.۹%) and n-tetradecan (۵.۲%) and on leaf were E-nerolidol (۲۱.۰%), n-tetradecane (۱۵.۸%) and a-himachalene(۱۳.۳%),  in H. lysimachioides  on flower were a-pinene (۵۵.۰%), Z-b-ocimene (۳۰.۷%) and n-tetradecane (۲.۷%), in  H. perforatumon flower were E-b-farnesene (۱۴.۷%), n-hexadecanal (۹.۱%) and E-nerolidol (۷.۸%), and in H. triquetrifolium on flower were n-tetradecane (۲۱.۳%),  a-himachalene (۱۴.۲%) and a-pinene (۱۰.۷%), and on leaf were a-himachalen (۲۷%), n-tetradecane (۲۵.۷%) and n-pentadecane (۷.۰%).

H. dogonbadanicum, H. helianthemoides, H. hyssopifolium subsp. Elongatum, H. lysimachioides, H. perforatum, H. triquetrifolium, Hypericin, Essential oils, chemical composition, GC, GC/MS