Ursolic acid as a trypanocidal constituent in rosemary

The MeOH extract of the leaves of rosemary (Rosmarinus officinalis L.) completely inhibited the motility of cultured epimastigotes of Trypanosoma cruzi at the concentration of 2 mg/ml after 2 h of incubation. Activity-guided fractionation of the MeOH extract has resulted in the isolation of three triterpene acids, betulinic, oleanolie and ursolic acids. Ursolic acid stopped the movement of all T cruzi epimastigotes at the minimum concentration (MC100) of 40 mug/ml (88 mum) after 48h of incubation. Oleanolic acid was less active (MC100: 250mug/ml, 550mum) and betulinic acid was practically inactive.