MATERIALS AND METHODS

Plant material and essential oil: Aerial parts of the plant were collected at full flowering stage in 2006 from 3 mentioned habitats in Iran. Plant materials were dried at ambient temperature and shade condition. Voucher specimen is identified and deposited under No. 6679-THE at the herbarium of Faculty of Pharmacy, Tehran University of Medical Sciences. The essential oil of air-dried samples (100 g) of each site was isolated by hydro distillation for 3 h, using a Clevenger-type apparatus. The distillated oils were dried over anhydrous sodium sulfate and stored in tightly closed dark vials at 4°C (Amin et al., 2005) until analyzing time.

GC analysis: GC analysis was performed by using a thermoquest gas chromatography Shimadzu 9A, with a Flame Ionization Detector (FID) and carried out using fused silica capillary DB-5 column (60 m* 0.25 mm i.d., film thickness 0.25 μm). The operating conditions were as follows: Injector and detector temperatures were 250 and 300°C, respectively. Nitrogen was used as carrier gas at a flow rate of mL min^-1; oven temperature programmed 60-250°C at the rate of 5°C min^-1 and finally held isothermally for 10 min.

GC-MS analysis: GC-MS analysis was performed by using a thermoquest-finigan gas chromatograph Varian 3400, equipped with above mentioned column and coupled to trace Mass quadrupled detector. Helium was used as carrier gas with ionization voltage of 70 eV. Ion source and interface temperature were 200 and 250°C, respectively. Mass range was form m z^-1 43-456. Gas chromatographic conditions were as given for GC. Identification of compound: The chemical compounds of essential oil were identified by calculation of their retention indices under temperature-programmed conditions for n-alkanes (c8-c24) and the oil on DB-5 column under the same chromatographic conditions. Identification of individual compounds was made by comparison of their Mass spectra with those of the internal reference Mass spectra library or with authentic compounds and confirmed by comparison of their retention indices with authentic compounds in literature (Adams, 2004; Connolly and Hill, 1991). For quantitative purpose, relative area percentages obtained by GC/FID were used without the use of correction factors.

RESULTS AND DISCUSSION

The average yield of essential oil in 3 areas were 0.1 to 0.15% (Hamedan = 0.1%, Shahr-e-Kord = 0.1%, Arak = 0.15%). The identified compounds of essential oil were different in these 3 habitats (Hamedan 103, Shahr-e-Kord 78 and Arak 55 compounds) and were shown in Table 1. Based on identified compounds we recognized over 95% of total oil of Camphorosma monspeliaca L. in 3 mentioned areas (Hamedan 95.057%, Shahr-e-kord 95.235 % and Arak 95.038%).

Overall, 104 components were identified over 95% of total essential oil of Camphorosma monspeliaca L. (Table 1) based on GC/MS data of three habitats (Hamedan 103, Shahr-e-Kord 78 and Arak 55 compounds). The major same components of three areas were α-pinene (10.2-15.7%), Citronellyl pentanoate, (2.6-8.4), endo-1-bourbonanol (1.99-7.3%), α-fenchene (4.7-5.9%), trans-pinocarveol (2.3-3.4%), limonene (2.5-3.1%), pinocarvone (2.4-3.1%), camphene (1.8-2.8%) and dill ether (1-1.5%). These results are very different from the only pre-report on the essential oil of Camphorosma monspeliaca L. (Bahernik and Mirza, 2003) which characterized some other components e.g., α-cadinol (9.1%), octen-3-ol (8.2%), β-eudesmol (7.3%), β-bisabolene (6.1%), 2-tridecanone (5.1%), β-cubebene (3.4%), neryl acetate (3.0%) and no data for collection localities.

Comparison of the percentage of 9 major compounds based on GC/FID data, showed that these compounds are in higher amount with Arak area, while it has the higher amount of soil salinity (9.41 dS m^-1) and lower amount of annual precipitation (222.2 mm) among these three areas (Table 1). It is very interesting that camphor, a responsible compound for Kafuri smel’s is omitted in the essential oil belonging to Arak area (Table 1) and it may be causes for livestock grazing of this species more simply than two other areas that having camphor.

Table 1:	Chemical composition and percent of the essential oil of Camphorosma monspeliaca L. in 3 studying habitats of Iran
RT: Retention Time, RRI: Relative Retention Indices, (%) (GC): Percentage according to GC spectrum, H: Hamedan, SH: Shahr-e-Kord, A: Arak

α-pinene, with 15.76% of the total essential oil of Arak samples is the major chemical component of these 3 areas (Table 1). Hamedan area, is the second’s one in this comparative stage while it has the second range of soil salinity (4.15 dS m^-1) but first range of annual precipitation (334.7 mm)and the most amount of chemical components (103 compounds). It is mentioned that the number of components were increased with increasing of annual precipitation (334.7 mm for Hamedan) and decreased based on increasing of soil salinity (9.41d S m^-1 for Arak), so however Camphorosma monspeliaca L. is a halophyte plant but it will produce more essential components based on local annual precipitation.

Since some of major components of essential oil of Camphorosma monspeliaca L. like Pinocarvone and trans-Pinocarveol are anti-microbial compounds (Asakawa et al., 1986) we recommend the in vivo and in vitro experiments for determining the anti-microbial activity of this plant.