Abstract: The chemical composition of the essential oils from flowering parts of Nepeta cilicia Boiss. apud Bentham and Phlomis viscosa Poiret from Turkey was determined by GC/MS. The main constituents of the essential oils were obtained as limonene (44.75%) in P. viscosa and β-caryophyllene (24.4%).
INTRODUCTION
Turkey is regarded as an important gene-center for Labiatae (Lamiaceae). The family is represented in Turkey by 45 genera, 546 species and a total of 731 taxa. The rate of endemism in the family is 44.2%. In terms of endemism, Labiatae family is the third richest family in Turkey (Başer, 1993). Plants of the genus Nepeta (Lamiaceae), commonly known as catmints, are distributed in Europe, Asia and a few areas of Africa. The genus Nepeta is represented in Turkey by 33 species, 17 of which are endemic. Some species of the genus have been used in folk medicine and some of their constituents, posses biological activities (Kökdil et al., 1997). Some Nepeta sp. are used as exciting and in stomach diseases in Turkey (Baytop, 1984).
The published result reveal that major volatile constituents obtained from Nepeta species nepetalactones (Regnier et al., 1967; Tzakou et al., 2000; Dabiri and Sefidkan, 2003; Sefidkon and Akbarinia, 2003). However some differences in essential oil composition of Nepeta species revealed that other terpenic compounds (e.g., 1,8-cineole, citronellol, linalool, linoleic acid and spathulenol) are the main components (Regnier et al., 1967; Domokos et al., 1994; Kalpoutzakis et al., 2001; Senatore and Özcan, 2003; Mehrabani et al., 2004).
N. cilicia Boiss. apud Bentham is spreaded to South Anatolia in Turkey and grows cliffs, rocks, gullies, limestone and soil slopes, coniferous and deciduous woods and at an altitude of 900-2700 m (Davis, 1982).
The genus Phlomis, consists of about more than 100 species; Africa, Asia, Europe. Some Phlomis species are used as tonics and stimulants in Anatolian folk medicine (Baytop, 1984). P. viscosa Poiret is spreaded to mainly S. Anatolia, Syria, Lebanon, Palestine. 34 of them are found among the flora of Turkey of which 21 are endemic P. viscosa grows Quercus scrub, rocky slopes, schitose hillsides and at an altitude of 300-1440 m (Davis, 1982).
Essential oil of N. cilicia collected from different area of Turkey were studied by Kökdil et al. (1997). Contrary to N. cilicia, there was no study concerning the essential oil composition of P. viscosa, as far as we know. Essential oil composition and glycosides from Turkish Phlomis spp. were studied some authors (Çalis and Kırmızıpekmez, 2004; Ismailoglu et al., 2002; Demirci et al., 2003). The composition of the essential oil plants can be very different from one location to another and these components correspond very different activities and organoleptic properties (Guillen and Manzanos, 1998). For this reason, it is very important to determine the real composition of the wild plants. In this study we report the essential oil composition of N. cilicia and P. viscosa growing wild in Southestern of Turkey.
MATERIALS AND METHODS
Plant materials: N. cilicia was collected from Başkonuş Mountain in June (altitude 1450 m) and P. viscosa from Çimendaği in K. Maras in July (altitude 1900 m). Voucher specimens are kept at the herbarium of the Science and Letter Faculty, University of KSU in K. Maraş, Turkey.
Isolation of the essential oils: The air dried flowering parts and leaves of the plants were hydrodistilled for 3 h using a Clevenger type apparatus according to the standard procedure described in the Sainte-Ruffine (1975).
Chemical analysis of the essential oils: The chemical composition of the essential oils was determined with a G 1800 B GCD system with an electron iozination detector (Hewlett-Packard Co, Polo All, CA) for high-resolution gas chromotography-mass spectrometry (GC-MS) analysis. Essential oils were injected into HP-5 fused silica capillary column (30 mx0.25 mm ) was used with helium as the carrier gas (1 mL min–1). The temperature programme was 80 °C for 2 min and 80-200 °C at 4°C min–1 . MS were taken at 70 eV. The scanning range was 45-450 m/z.
RESULTS AND DISCUSSION
The general chemical profiles of the tested oils, the percentage content of the components are summarized in Table 1 in order of elution from silica capillary column.
In the oil of N. cilicia 13 components were identified, which represented 97.55% of the total detected constituents. The major constituents of the oil were limonene (44.75%), β-pinene (13.6%), β-caryophyllene (11.2%) and caryophyllene oxide (9%). Other components were present in amount less than 9%. The earlier literatures results about Turkish Nepeta species showed different oil composition Kökdil et al. (1998) reported that N. italica and N. sulfuriflora includes 1,8-cineole as main component. The major components being linalool (40.5%), 1,8-cineole (20.8%) in N. betonicifolia oil (Senatore and Özcan, 2003) Başer and Özek (1994) reported that 4aα, 7α, 7a β- nepetalactone was found to be the major component in the N. caeserea oil. The major constituents found were nerolidol (31.7%) in the N. nuda ssp. albiflora pils (Sarer and Konuklugil, 1996).
In regard to the previously report essential oil content of N. cilicia had high caryophyllene oxide (40.7%) and β-caryophyllene (15.7%) (Kökdil et al., 1997). Present results have some differences than Kökdil et al. (1997) results. These chemical differences can be most probably explained differences of collecting area. Because the collecting area of Kökdil et al. (1997) was near Anamur in Southern Turkey that so far from our area.
In the oil of P. viscosa 15 compound constituting 80. 85% of the oil were identified. β-caryophyllene (24.4%) was major component in the oil. Followed by alloaromadendrene (11%), α-humulene (6.1%) and germacrene-D (4.7%). Our result confirmed by Demirci et al. (2003). They report that essential oil of Turkish P. linearis was indicate β-caryophyllene, germacrene-D and caryophyllene oxide as main component.
| Table 1: | Percentage composition of the oils of N. cilicia and P. viscosa |
The results of the present investigation indicate differences to the composition of the oils of Phlomis species reported earlier. α-pinene, limonene and trans-caryophyllene were found as its main components in P. lanata (Couladis et al., 2000). Essential oils of P. persica and P. chorassanica were rich in sesquiterpenes (81.3 and 90.1%, respectively) and germacrene-D (32.5 and 515%, respectively) as the major component (Sarkhail et al., 2004). Morteza-Semnani et al. (2003) reported that the major constituents of the P. herba-venti leaf essential oil were germacrene-D (33.9%), hexadecanoic acid (12.9%) and α-pinene (9.4%) and the major constituents of the flower essential oil were hexadecanoic acid (33.1%), 6, 10, 14-trimethylpentadecan-2-one (16.2%), 3-methyltetradecane (6.7%) and germacrene D (6.7%).
Published studies have indicated a high degree of variability in quantity and composition of the volatile oils from different populations and clones (Skoula et al., 2000). Altough the chemical characters are generally inherited plants are capable of adapting themselves to changing climatic and edaphic conditions. Such changes may in the long run lead to the evolution of new taxa (Başer, 2002). Also the highly heterogenous soil and climatic conditions of the Mediterranean area have resulted in an increased diversity of medicinal plants (Nicolaidis, 1993).
As a conclusion oil of N. cilicia are rich in limonene and P. viscosa are rich in β-caryophyllene and due to these high content, they can be considered as substitues for these plants for medical purposes and cosmetics.
ACKNOWLEDGMENTS
We thank Dr. Uzi Ravid, Department of Aromatic, Medicinal and Spice Crops, ARO, Newe Ya’ar Research Center, Ramat Yishay 30095, Israel and Dr. Ahmet Ilçim, Department of Biology, Faculty of Science and Letters, University of KSU, K. Maraş, Turkey.