Phytochemical Analysis and Antileishmanial Activity of Clerodendrum myricoides and Salvadora persica Plant Extracts against Leishmania major

Introduction: Clerodendrum myricoides and Salvadora persica have been reported in management of leishmaniasis which is one of the neglected tropical diseases. The study aimed at undertaking phytochemical analysis as well as investigating the in vitro antileishmanial activity of Clerodendrum myricoides and Salvadora persica extracts on promastigote and amastigote forms of Leishmania major. Materials and Methods: Solvent extraction of the stem parts of the two plants was performed using water, methanol, petroleum ether, dichloromethane and ethyl acetate. Minimum inhibitory concentration (MIC), anti-amastigote and nitric oxide production assays were carried out to demonstrate antileishmanial activity of these plant extracts against the two forms of Leishmania major parasite species: promastigote and amastigote. Cytotoxicity assay was then conducted to assess their safe use as herbal medicinal products. Results: Both plants showed presence of alkaloids, terpenoids, phenols, anthraquinones and saponins. The Clerodendrum myricoides water extract demonstrated the best potential antileishmanial activity against Leishmania major promastigotes (MIC=625 μg/ml). The dichloromethane and petroleum ether extract were nontoxic to vero cells but showed moderate to weak activity against Leishmania major promastigotes (MIC=1250 μg/ml; 2500 μg/ml) and amastigotes respectively. The Salvadora persica ethyl acetate, successive methanol and dichloromethane extracts recorded the most potential activity towards both Leishmania major promastigotes and amastigotes. Conclusions: All Salvadora persica and Clerodendrum myricoides extracts have potential antileishmanial activity and may offer a cheaper alternative to the more expensive pentavalent antimonials.