Tehran University of Medical Sciences Iranian Journal of Parasitology 1735-7020 15 1 2020 03 09 22 30 Hossein MAHMOUDVAND Razi Herbal Medicines Research Center, Lorestan University of Medical Sciences, Khorramabad, Iran AND Department of Laboratory Sciences, School of Allied Medicine, Lorestan University of Medical Sciences, Khorramabad, Iran Amir TAVAKOLI KARESHK Infectious Diseases Research Center, Birjand University of Medical Sciences, Birjand, Iran Mohammad NABI MORADI Department of Laboratory Sciences, School of Allied Medicine, Lorestan University of Medical Sciences, Khorramabad, Iran Lianet MONZOTE FIDALGO Department of Parasitology, Institute of Tropical Medicine "Pedro Kourí", La Lisa, Havana, Cuba Seyed Reza MIRBADIE School of Medicine, Shahroud University of Medical Sciences, Shahroud, Iran Massumeh NIAZI Student Research Committee, Lorestan University of Medical Sciences, Khorramabad, Iran Mehrdad KHATAMI Bam University of Medical Sciences, Bam, Iran 2020 03 09 Background: Broad spectrums of pharmacological properties, including antimicrobial activity have been attributed to Zataria multiflora Boiss (Laminaceae). The in vivo efficacy and safety of Z. multiflora essential oil (ZM-EO) were evaluated against acute toxoplasmosis caused by Toxoplasma gondii (Sarcocystidae) in mice. Methods: Z. multiflora (aerial parts) was obtained from the rural districts of Kerman city (Kerman Province) Southwestern Iran, in May of 2016. Male NMRI mice were orally treated with normal saline (control group) and ZM-EO at the doses of 0.2 and 0.4 mL/kg once a day for 14 d (8 mice in each group). On the 15th day, the mice were infected with 104 tachyzoites of T. gondii RH strain by intraperitoneal route. The mortality rate and parasite load were determined in the infected mice. Additionally, 24 mice were applied to examine the sub-acute toxicity of ZM-EO at the above doses after treatment during 14 d. Results: GC/MS analysis displayed that the key constituents were thymol (45.4%), carvacrol (23%) and p-cymene (10.6%), respectively. Overall, 100% mortality was observed on the 8th and 9th days in treated mice with the concentrations of 0.2 and 0.4 mL/kg, respectively. The mean number of tachyzoites in the mice treated with 0.2 and 0.4 mL/kg of ZM-EO were 189×104 and 76×104 cell/mL, respectively, meaningfully (P<0.05) reduced compared with the control mice. Results also demonstrated that ZM-EO had no important toxicity on mice. Conclusion: The results demonstrated the efficacy of ZM-EO against acute toxoplasmosis. Nevertheless, supplementary surveys are mandatory to examine its precise effects, mainly immunomodulatory effect on toxoplasmosis. https://ijpa.tums.ac.ir/index.php/ijpa/article/view/2829 https://ijpa.tums.ac.ir/index.php/ijpa/article/download/2829/1008