In vitro evaluation of quercetin and quercetin-loaded microemulsion for Leishmania major growth inhibition

Leishmaniasis is caused by the Leishmania parasite, leading to cutaneous lesions or infections of internal organs. The therapy is challenging, and the search for new medications and alternative therapies continues. This study investigates the impact of quercetin-loaded microemulsion (MEs-QCT) on Leishmania major (L. major) in culture media and compares it with the effects of quercetin (QCT).

We used the standard strain of L. major in this experiment. MEs formulations were created with an oily phase, a surfactant, a co-surfactant, and distilled water. Transmission electron microscopy (TEM) and Scatterscope were employed to analyze the MEs. The MTT test was employed to assess the survival rates of promastigotes and macrophages (MΦs).

MEs-QCT demonstrated the highest efficacy against L. major promastigotes. The IC₅₀ values for QCT, MEs-QCT, and MEs were determined to be 315.3, 130, and 1378 μg/mL, respectively. The findings of this study indicate that MEs-QCT possesses a greater potential for amastigote lethality compared to QCT and the control group. In all time periods, the proportion of MΦs mortality was lower in MEs-QCT than in QCT.

The results showed that MEs-QCT had a higher effect with less toxicity compared to QCT.