Cutaneous leishmaniasis is one of the common diseases between humans and animals that is considered as a health problem in Iran and many countries around the world. At present, glucantime is used to treat cutaneous leishmaniasis. Due to its high side effects and resistance, the use of alternative therapies, especially the use of plants and natural compounds, has been considered by researchers. The aim of this study was to investigate the antileishmania activity of methanolic extract of dandelion root (Taraxacum officinale) on Leishmania major in vitro.

In this experimental study, the extract was prepared by Soxhlet method and to evaluate the effect of methanolic extract of dandelion root on L. major parasite at concentrations of 300-1200 mg / ml. Glucantime was considered as positive control and distilled water was considered as negative control. Then, 106 live parasites were added to all tubes and all groups were kept at 25 ±1 °C. At 24, 48 and 72 hours, the number of live parasites was counted by Trypan Blue using a neobar slide and light microscope (Hemocytometer method). Then the IC50 value for the above extract was calculated using SigmaPlot™ 13 software. It should be noted that all steps of the experiment were done triplicate and the results were considered as average.

The IC50 content of methanolic extract of dandelion root after 24, 48 and 72 hours on L. major was calculated to be 1.04, 0.9 and 0.68 mg / ml. The highest mortality (100%) was observed at a concentration of 1200 μg / ml after 72 hours of exposure.

Methanolic extract of dandelion root in different concentrations has an inhibitory effect on the growth of L. major and it is suggested that more and more complete studies be performed on the components of this plant and the lethal effect of the parasite in vivo.