quantification of betulinic, oleanolic and ursolic acids as medicinally important triterpenoids in some thymus species from iran

background and objectives: 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. methods: 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. results: 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. conclusion: 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.