فهرست مطالب z. bakhtiar

Betulinic acid (BA), oleanolic acid (OA) and ursolic acid (UA) are well-known pentacyclic triterpenoids (PTs), which are produced by plants. They possess a variety of beneficial effects including anti-inflammatory, hepatoprotective, antitumor, anti-HIV, antimicrobial, gastroprotective, and antihyperlipidemic activities. In the present study, quantitative determination of these compounds was simultaneously carried out in some Thymus species native to Iran i.e. T. daenensis, T. pubescens, T. persicus and T. caramanicus.

Lyophilized and powdered plant material (1.0 g) was drenched in MeOH and immediately sonicated at room temperature. The methanol extract was further separated into organic and aqueous layers. The organic layer was dissolved in HPLC grade methanol, filtered and analyzed by reverse-phase HPLC.

The maximum content of BA, OA and UA were determined in the aerial parts of T. persicus as856.9, 480.6 and 941.7 mg per 100 g dry weight (DW) of plant, respectively while the other Thymus species had an almost negligible amount of these compounds.

Results showed that the aerial parts of T. persicus could be a considerable source of these PTs which might be attractive for future phytochemical and biological investigations according to importance of their health benefits.

Thymus persicus is an endemic species of the genus Thymus (Lamiaceae) which grows in Zanjan and West Azerbaijan (Takab) provinces of Iran. Among the Iranian Thymus species, T. persicus is well differentiated by having the smallest leaf width among Thymus species with long non-glandular and short glandular hairs. In order to evaluate the phylogenetic relationships of the T. persicus and T. marandensis Jamzad, the recently and assumed related species to T. brachychilus Jalas and T. leucotrichus Hal., a molecular analysis based on nrDNA ITS sequences of 25 accessions belonging to 19 species of Thymus together with representatives of genera Origanum, Thymbra, Satureja, Micromeria, Gontscharovia, Ziziphora, Saccocalyx and Zataria was performed. The results of phylogenetic analysis showed that the genus Thymus is paraphyletic when the monotypic genus Saccocalyx is included and its sister relationship with Origanum was confirmed. While the phylogenetic position of T. persicus among the other taxa of Thymus is appeared unresolved. T. marandensis turned out to be the sister to a group of Thymus species including T. carmanicus, T. migricus, T. pubescens, T. trautvetteri and T. daenensis.