Background: Because there is no effective drug therapy for hydatid cyst yet, assessment and finding of some new agents especially from herbal origin with a desired scolicidal effect attracts great attention for treatment and pre-surgical use to prevent the hydatid cyst recurrence. In the present study, the scolicidal effect of ethanolic extract of Allium sativum, Mentha longifola and Zingiber officinale were investigated. Methods: Suspension of protoscolices was obtained an aseptically from sheep livers containing hydatid cysts. Three concentrations of Allium sativum, Mentha longifola and Zingiber officinale extract (10, 25 and 50 mg/ml) were used for 5,10,15, 20, 25 and 30 min. Viability of protoscolices was confirmed by 0.1% Eosin staining. Results: Present study showed that ethanolic extract of garlic (Allium sativum) had more potent protoscolicid effects among all the 3 plants and killed 100% of protoscolices in 25 mg/ml, 50 mg/ml on a minimum of 30, 15 min of application, respectively. While the rate of dead protoscolices was 13.7% in the control group, while protoscolices were exposed to Mentha longifola extract at the concentration of 25 mg/ml, the rate of dead protoscolices increased to 83.1%, 87.1%, 98.0%, 99.2%, 99.9%, and100% after 5,10,15, 20, 25 and 30 min respectively. One hundred percent mortality rate was observed at concentration of 50 mg/ml after 20 min of exposure. The scolicidal activity of Zingiber officinale extract at the concentration of 25 mg/ml killed (19.1, 22.5, 31.5, 41.0, 50.6 and 60.2) % of the protoscolices after 5, 10, 15, 20, 25 and 30 min of application respectively, but scolicidal activity of Zingiber officinale extract increased at the concentration of 50 mg/ml to 98.8% after 30 min of application then 100% after 35 minutes. Conclusions: Ethanolic extract of garlic, Mentha longifola and ginger showed high protoscolicidal activity in vitro. It may be considered as an effective natural agent used in hydatid cyst treatment and pre-surgery to prevent secondary cyst recurrence. However, further biological and phytochemical investigations aiming to identify the active compounds of these extracts and other pure compounds from these plants to find other ant parasitic agents that are not affected when treated with common therapeutic agents.
