Screening of the in vitro amoebicidal activities of Pastinaca armenea (Fisch. & C.A.Mey.) and Inula oculus-christi (L.) on Acanthamoeba castellanii cysts and trophozoites.

The aim of this study is to evaluate the in vitro amoebicidal activity of the aqueous extracts of Pastinaca armenea and Inula oculus-christi from Turkey. In the presence of aqueous extracts (ranging from 1.0 to 32.0 mg/ml), numbers of the viable Acanthamoeba castellanii trophozoites and cysts were decreased during the experimental process. Both extracts showed a time- and dose-dependent amoebicidal action on the trophozoites and cysts. Among the extracts tested, I. oculus showed the strongest amoebicidal effect on the trophozoites and cysts. In the presence of 32.00 mg/ml extract solution in the media, no viable trophozoites were determined from the time of 24 h. Moreover, in the presence of 16.00 mg/ml I. oculus-christi extract, no viable trophozoites were detected in 72 h of the experiment. Effectiveness of I. oculus-christi extract was found moderate against the cysts. In the presence of 32.00 mg/ml extract, only 25.3% of the total cysts were killed effectively. In the case of P. armenea, 40.3% and 23.0% of the trophozoites and cysts were killed in the presence of 32.00 mg/ml extract at the end of the experimental process (72 h), respectively.