In vitro effect of alpha-bisabolol and its synthetic derivatives on macrophages, promastigotes, and amastigotes of Leishmania amazonensis and Leishmania infantum .

Cutaneous and visceral leishmaniasis are public health problems in Africa, Asia, Europe, and America. The treatment has a high cost and toxicity. Thus, this work aims to evaluate the leishmanicidal activity of alpha-bisabolol and its three synthetic derivatives, P1, P2, and P3, on the promastigotes and amastigotes Leishmania infantum and L. amazonensis forms. Alpha-bisabolol showed the lowest IC 50 with 3.43 for L. amazonensis promastigotes, while P1 was the most toxic for L. infantum with an IC 50 of 9.10. The derivative P3 was better for the amastigote form, with an IC 50 of 3.39 for L. amazonensis . All the compounds effectively decreased the intracellular load of amastigote and its ability to turn promastigote again. Thus, alpha-bisabolol and its three synthetic derivatives were effective in their leishmanicidal activity. Therefore, it can be an option for developing new treatments against leishmaniasis.