GC-MS analysis and antioxidant activities of essential oils of two cultivated Artemisia species (original) (raw)

2007, Chemistry of Natural Compounds

Artemisia is a fairly large genus within the family Asteraceae (alt. Compositae), with ca. 300 individual species of aromatic and medicinal plants, which are usually found as small fragrant shrubs or herbs in the northern hemisphere [1, 2]. While some of their essential oils are used in perfumery and medicine, the leaves of some species are used as culinary herbs [3]. The various pharmacological effects of Artemisia species, e.g., anticonvulsant [4], apoptosis [5], immunosuppressive [6], antipeptic ulcer [7], anthelmintic [8], antimalaria [9], anti-inflammatory [10], anti-HIV, antiplatelet aggregation [11], antibacterial [12] and antifungal effects [13], have previously been reported. We now report on the determination of the main constituents of the essential oils from two cultivated Artemisia species, Artemisia fragrans and A. austriaca, aiming at the comparison between the composition of the oils from these cultivated species with those of wild species. The free radical scavenging properties (antioxidant) of these essential oils using the DPPH assay are also reported. The aerial parts of A. fragrans Willd. and A. austriaca Jacq., cultivated in the Botanical Garden of the Drug Applied Research Center (Tabriz University of Medical Sciences, Tabriz, Iran), were collected during August-September 2004 (flowering). The steam distillation for 3 h of the aerial parts of two cultivated species, Artemisia fragrans and A. austriaca, yielded essential oils 0.95% and 1.1%, respectively. The percentage yield of the essential oil of A. austriaca was more than that of A. fragrans. While the total yield of essential oils of the cultivated A. fragrans was similar to that of this species growing wild (0.97%) [2], the yield was much higher, almost doubled, in the cultivated A. austriaca than its wild variety (0.59%) [14]. The identified constituents of the oils of A. fragrans and A. austriaca are listed in Table 1. The GC-MS analysis of the aerial parts of A. fragrans and A. austriaca led to the identification and quantification of a total of 14 main compounds (Table 1), and these compounds accounted for the 88.7% and 91.5% of the total components present, respectively. Camphor (2), which has a bornane skeleton, and 1,8-cineole (7) are the main components of the essential oils of Artemisia species [2, 14]. According to a previously published reports [14, 15], the main components of the essential oil of A. austriaca were camphor (2, 45.5%), 1,8-cineole (7, 30.4%), camphene (1, 6.5%), α-terpineol (3.2%), α-pinene (3.0%), terpinen-4-ol (8, 2.9%), and p-cymene, and those of the essential oil of A. fragrans were camphor (2, 46.0%), 1,8-cineole (7, 23.7%), camphene (1, 7.9%), borneol (4.9%), and germacrene D (14, 1.9%) [2, 16, 17]. All these previously published reports were on the species that were collected wild. A clear variation in the profile as well as in the amounts of individual compounds present in the cultivated species (Table 1) in the present study was identified when compared with wild species. Both in the cultivated A. fragrans and A. asutriaca, the two major components were camphor (2, 54.92% and 40.59%, respectively) and 1,8-cineole (7, 11.48% and 27.97%, respectively), which accounted for ~70% of the total essential oils (Table 1). In addition to 2 and 7, while in the cultivated A. fragrans, α-thujone (11, 9.21%), β-thujone (12, 4.83%), and germacrene D (14, 3.57%) were identified in significant amounts, camphene (1, 3.95%) and trans-pinocarveol (6, 2.69%) were present in significant proportions in the cultivated A. austriaca.