In-vitro giardicidal effect of aqueous and alcoholic extracts of Asafoetida on Giardia lamblia cyst

Giardia lamblia, Giardiasis causative protozoa, is one of the most common etiologic agents of diarrhea throughout the world especially in Iran. Asafoetida, an oleo-gum-resin (called Anjodan in Farsi) obtained from an Iranian endemic herb, Ferula Assa-foetida has been used in treating of different diseases, particularly parasitic ones. The aim of this study was in-vitro evaluating of the effect of Asafoetida aqueous and alcoholic extracts on Giardia lamblia cysts. 500 µl of each of 1.25, 2.5, 5 and 20 mg/ml concentrtions of asafoetida aqueous and ethanol extracts was added to 500 µl of purified Giardia cysts,respectively. The mixtures were kept at 4, 24 and 37°C. The Giardicidal activity of the extracts was measured 1, 2, 3, 4 and 5 hour (s) after exposure through 0.1% eosin dye staining and microscopic enumeration method. The gathered data was analyzed by means of one- way variance, Pearson's correlation coefficient and Independent T-test. The highest Giardicidal effect of Asafoetida ethanol extract was 100% at 37°C, belonging to 20 mg/ml and in the 4th hour after experiment, while the maximum Giardicidal effect of Asafoetida aqueous extract was 57.23% at the same temperature and with the same concentration, in the 5th hour. There was a significant difference between Giardicidal effect of ethanol and water extracts with all concentrations and at different whiles and temperatures (P<0.005). Giardicidal effect of both extracts significantly increased due to rising the concentration, time and temperature (P<0.0001). Ethanol and aqueous extracts of asafetida have in-vitro Giardicidal effect on Giardia lamblia cysts. Ethanol extract has more Giardicidal effect.