Chemical Composition, Larvicidal and Repellent Activities of Wild Plant Essential Oils against Aedes aegypti

SIMPLE SUMMARY: Mosquitoes are the deadliest insects alive due to the transmission of pathogens that cause diseases. Plant essential oils are considered an alternative to synthetic repellents for controlling mosquitoes. We have investigated the repellent and larvicidal activity of six plant essential oils against adult female mosquitos and the larvae of yellow fever mosquitos, Aedes aegypti. The essential oils extracted from Mentha longifolia, Zanthoxylum armatum, Erigeron bonariensis, and E. canadensis have the potential to manage Ae. aegypti at the larval stage. Moreover, M. longifolia, E. canadensis, E. bonariensis, and Salsola imbricata essential oils exhibited prolonged mosquito-repellent activity against adult female Ae. Aegypti; these oils might be used to develop formulations that are efficient and cost-effective as mosquito repellents without harming humans and the environment. ABSTRACT: Bio-degradable and eco-friendly essential oils (EOs) extracted from Mentha longifolia, Salsola imbricata, Erigeron bonariensis, E. canadensis, Ailanthus altissima, and Zanthoxylum armatum were investigated for their repellent and larvicidal potential against Aedes aegypti mosquitoes. The EOs of M. longifolia, S. imbricata, E. bonariensis, E. canadensis, A. altissima, and Z. armatum exhibited 99.0%, 96.8%, 40.2%, 41.7%, 29.1%, and 13.2% repellency against mosquitoes at a tested dose of 33.3 μg/cm(2), respectively. In time span bioassays, the EOs of M. longifolia, S. imbricata, E. bonariensis, and E. canadensis showed more than 40% repellency for 60 min at a tested dose of 330 μg/cm(2). Larvicidal bioassays revealed that larvae of Ae. aegypti were the most susceptible to M. longifolia (LC(50), 39.3 mg/L), E. bonariensis (LC(50), 26.0 mg/L), E. canadensis (LC(50), 35.7 mg/L), and Z. armatum (LC(50), 35.9 mg/L) EOs upon 48 h exposure. The most abundant constituents in the EOs of M. longifolia, S. imbricata, E. bonariensis, E. canadensis and A. altissima were piperitone oxide (45.5%), carvone (39.9%), matricaria ester (43.1%), (31.7%) and eugenol (24.4%), respectively. Our study demonstrates that EOs of M. longifolia, S. imbricata, E. bonariensis, and E. canadensis might be used to control Ae. aegypti mosquitoes without harming humans or the environment.