In Vitro Effect of Methanolic Extract of Quercus infectoria Galls on Promastigotes and Amastigotes of Leishmania major (MRHO/IR/75/ER)

Leishmania major is a flagellated parasitic protozoan that causes cutaneous leishmaniasis. Pentavalent antimony compounds are considered the first-line drugs in the treatment of cutaneous leishmaniasis. However, the use of these drugs is associated with numerous limitations and side effects. Therefore, there is a need for herbal and natural alternatives for these compounds with fewer side effects. In this study, we evaluated the in vitro activity of methanol extract of Quercus infectoria (oak galls) against promastigotes and amastigotes of L. major.

In this experimental study, the effect of 10, 100, 500 and 1000 µg/ml of methanolic extract of oak galls and 100, 500, 1000 and 10000 µg/ml of Glucantime was evaluated against L. major promastigotes using direct cell counting and MTT assay. Moreover, the effect of different concentrations of the extract and Glucantime was investigated on the mean number of amastigotes in macrophages after 24 and 48 hours. Data were analyzed using SPSS 16 and one- way analysis of variance.

The half-maximal inhibitory concentration of the oak gall extract and Glucantime was 75 µg/ml and 221 µg/ml after 24 hours, respectively. After 24 hours, the mean number of amastigotes per macrophage was lowest at concentrations of 1000 µg/ml of the extract (0.9) and 10000 µg/ml of Glucantime (0.85).

Considering the inhibition of intracellular and extracellular growth of L. major, the oak gall extract might be used as an efficient and safe agent for treatment of cutaneous leishmaniasis.