Prolonged Repellent Activity of Plant Essential Oils against Dengue Vector, Aedes aegypti

Repellents are effective personal protective means against outdoor biting mosquitoes. Repellent formulations composed of EOs are finding increased popularity among consumers. In this study, after an initial screening of 11 essential oils (EOs) at the concentration of 33 μg/cm , five of the most repellent EOs, , (fruit peels), (leaves), , and were further investigated for repellent activity against mosquitoes in time span bioassays. When tested at the concentrations of 33 μg/cm , 165 μg/cm and 330 μg/cm , the EO of showed the longest repellent effect up to 75, 90 and 135 min, respectively, which was followed by (peels) for 60, 90 and 120 min, for 45, 60 and 90 min, and (leaves) for 30, 45 and 75 min. Notably, the EO of tested at the dose of 330 μg/cm showed complete protection for 60 min which was similar to the commercial mosquito repellent DEET. Gas chromatographic-mass spectrometric analyses of the EOs revealed camphor (19.7%), limonene (92.7%), sabinene (24.9%), carvone (82.6%), and -ascaridole (38.8%) as the major constituents of , (peels), (leaves), , and , respectively. The results of the present study could help develop plant-based commercial repellents to protect humans from dengue mosquitoes.