Antimalarial evaluation of selected medicinal plant extracts used in Iranian traditional medicine

Abstract

<strong><em>Objective(s)</em></strong>: In an attempt to discover new natural active extracts against malaria parasites, the present study evaluated the antiplasmodial properties of selected plants based on Iranian traditional medicine.<br /> <strong><em>Materials and Methods: </em></strong>Ten plant species found in Iran were selected and collected based on the available literature about the Iranian traditional medicine. The methanolic extracts of these plants were investigated for <em>in vitro</em> antimalarial properties against chloroquine-sensitive (3D7) and multi-drug resistant (K1) strains of <em>Plasmodium falciparum</em>. Their <em>in vivo</em> activity against <em>Plasmodium berghei </em>infection in mice was also determined. Cytotoxicity tests were carried out using the Raji cells line using the MTT assay. The extracts were phytochemically screened for their active constituents.<br /> <strong><em>Results:</em></strong> According to the IC₅₀ and selectivity index (SI) values, of the 10 selected plant species, <em>Citrullus colocynthis</em>, <em>Physalis alkekengi</em>, and <em>Solanum nigrum</em> displayed potent <em>in vitro</em> antimalarial activity against both 3D7 and K1 strains with no toxicity (IC₅₀= 2.01-18.67 µg/ml and SI=3.55 to 19.25). Comparisons between treated and untreated control mice showed that the mentioned plant species reduced parasitemia by 65.08%, 57.97%, and 60.68%, respectively. The existence of antiplasmodial compounds was detected in these plant extracts.<br /> <strong><em>Conclusion:</em></strong> This was the first study to highlight the <em>in vitro</em> and <em>in vivo</em> antiplasmodial effects of <em>C. colocynthis</em>, <em>P. alkekengi</em>, and <em>S. nigrum </em>in Iran. Future studies can use these findings to design further biological tests to identify the active constituents of the mentioned plant species and clarify their mechanism of action.