Promising larvicidal effects of chitosan nanoparticles containing Laurus nobilis and Trachyspermum ammi essential oils against Anopheles stephensi

Malaria is still a dreadful vector-borne disease; the excessive use of chemical insecticides has led to resistance in vector mosquitoes, especially Anopheles stephensi. On the other hand, the lower effectiveness of essential oils (as green alternatives) compared to synthetic ones and the volatility of their ingredients is limited their use in adoption for eradication of these vectors. In this study, the chemical composition and larvicidal effects of essential oils of Laurus nobilis and Trachyspermum ammi against A. stephensi were investigated. An attempt was then made to improve their efficacy by preparing chitosan nanoparticles containing each essential oil. Chitosan nanoparticles containing T. ammi essential oil with a particle size of 158 +/- 7 nm and narrow particle size distribution (SPAN < 1) showed more larvicidal effects than samples with a lethal concentration of 50 (LC50) 13.67 mu g/mL. This formulation could be introduced as a potent and green candidate against other mosquitoes and potential field application scope.