Evaluation of Antileishmanial Effect of Hydroalcoholic Extract of Ganoderma Leucidum on Leishmania Major in Vitro

Background: Leishmania major is the causative agent of cutaneous leishmaniasis in Iran. Because of the side effects of current drugs and the emergence of drug resistance in some areas, researchers have been seeking for more effective and non-complicated compounds, especially herbal medicines and natural compounds, for the treatment of leishmaniasis. The aim of this study was to evaluate the antileishmanial effect of hydroalcoholic extract of Ganoderma leucidum on Leishmania major compared to commonly used drugs. Methods: Iranian Leishmania major parasite species (MRHO/IR/75/ER) was cultured in Novy-Mac Neal-Nicolle (NNN) and Roswell Park Memorial Institute-1640 (RPMI)-enriched media, and in the metacyclic phase transferred to a 96-well plate at the time of preparation of the hydroalcoholic extracts. Then, concentrations of 10, 50, 100, 150, and 200 µg/ml were used at 24, 48, and 72 hours. The amount of live promastigotes was assessed by using a hemocytometer and MTT colorimetric assay. Data were analyzed using Kolmogorov-Simonov, ANOVA, and repeated measures ANOVA tests, and P < 0.05 was considered as a meaningful level. Findings: The hydroalcoholic extract of this mushroom at high concentrations (150 and 200 µg/ml) inhibited the growth of the parasite significantly, and had a direct correlation with the increase of time (P < 0.001). Moreover, in the MTT method, it was a significant difference in the mean of optical absorption of different extract concentrations at 24, 48, and 72 hours (P < 0.001). Conclusion: The observed antileishmanial effect of Ganoderma leucidum extract on the number and growth of live promastigotes at high concentrations can be resulted due to its compounds such as tannins, flavonoids, triterophenides, and polysaccharides. It requires further research on the purification of its compounds and work on the animal model of Leishmaniasis.