Scutellaria is a member of Labiatae, distributed in mediteranean region and south Asia. In Iran 20 species are present in center, northern, northwest and western districts. The aerial parts of Scutellaria pinnatifida. Were collected from Touchal in Tehran province at full flowering stage in May 2004. Essential oil was isolated by hydrodistillation from the aerial parts of plant and analysed by a combination of capillary GC and GC/MS. The yeild of essential oil was in 0.07% (w/w). 29 compounds in the oil have been identified representing 96.6% of the oil. The main constituent was germacrene D (39%). Other main components were b-caryophyllene, farnesene and bicyclogermacrene.

Eucalyptus porosa was collected from Dezfool (Fadak Garden) in Martchn 2004. Dry leaves were hydrodistilled in a Clevenger type apparatus for 20min. to produce an oil at the yield of 0.57% (based on dry leaves). In order to quantitavely and qualitavely analyses, the oil was injected to Gc. Among twenty-one compounds which were identified in the oil, 1,8-cineole(58.6%), a–pinene (12.8%) and nopinone (3.11%) were the major constituents, respectively.

Introduction. Nepeta ispahanica Boiss. (Lamiaceae), is an endemic herbaceous plant, growing wild in Iran. Some of Nepeta species are used as medicinal plants in Iranian folk medicine. Because of biological activity of essential oils and in the course of studying on Nepta species, the essential oil of N. ispahanica is analyzed.Methods. Aerial parts of the wild plants of N. ispahanica were collected from Kolah-Ghazi in the south of Isfahan. The essential oil was obtained by hydrodistillation. The oil was analyzed by GC/MS method. Results. The aerial parts of N. ispahanica contained 0.4% (v/w) pale yellow essential oil. The major components were: 1,8-cineole (45.8%), ß-pinene (8.9%), 4aα,7α,7aα - nepetalactone (6.2%), α-terpineol (4.3%) and trans-ß-ocimene (3.3%).

The volatile constituents of Anthemis coelopoda Boiss. were isolated by hydrodistillation and analyzed by GC and GC/MS. In this study samples were collected from Gilan province in Rodbar on late May 2003. According to literature, this species was not the subject of research up to now and therefore its chemical composition is not well known. The major constituents of A. coelopoda Boiss. flower oil were Cis-chrysanthenyl acetate (27.3%), hexyl butanoate (16%), and myrcene (7%), while the leaf oil contained isobornyl formate (30.6%), Trans-ethyl chrysanthemumate (15%) and p-mentha-1,5-diene-8-ol (13.7.4%).

The erial parts of Geranium rotundifolium L. were collected during the flowering stage from National Botanical Garden of Iran in Jun 2001. Dry leaves of the plant were hydrodistilled for obtaining the essential oil. No significant amount of the oil was produced so it was separated from water by adding diethyl ether, and analysed by GC and GC/MS.The major constituents determind in leaf oil were a-terpinyl acetate (39.3%) and pulegone (27.7%), respectively.