Department of Entomology, Faculty of Agricultural Sciences and Technology, Bahauddin Zakariya University, Multan, 60800, Pakistan.
Department of Chemistry, COMSATS University Islamabad, Abbottabad Campus, Abbottabad, 22060, Pakistan.
Exp Parasitol. 2023 Jan;244:108424. doi: 10.1016/j.exppara.2022.108424. Epub 2022 Nov 12.
Aedes aegypti (Diptera: Culicidae) mosquito is an important vector of many disease-causing pathogens. An effective way to escape from these mosquito-borne diseases is to prevent mosquito bites. In the current study, essential oils of Lepidium pinnatifidum, Mentha longifolia, Origanum vulgare, and Agrimonia eupatoria were evaluated for their repellent potential against Ae. aegypti females. Essential oils were extracted using steam distillation from freshly collected aerial parts of the plants and tested against 4-5 day old females of Ae. aegypti through the human bait technique for repellency and repellent longevity assays. The chemical composition of extracted essential oils was explored by gas chromatography coupled with mass spectrometry (GC-MS). The essential oils of L. pinnatifidum, M. longifolia, O. vulgare, and A. eupatoria at a dose of 33 μg/cm showed 100%, 94%, 87%, and 83% mosquito repellent activity, respectively. Furthermore, M. longifolia and O. vulgare essential oils exhibited 100% repellency at a dose of 165 μg/cm, whereas A. eupatoria essential oil showed 100% repellency only at 330 μg/cm. In the time-span bioassay, M. longifolia and O. vulgare essential oils showed protection against Ae. aegypti bites for 90 and 75 min, respectively whereas both A. eupatoria and L. pinnatifidum were found active for 45 min. Phenylacetonitrile (94%), piperitone oxide (34%), carvacrol (20%) and α-pinene (62%) were the most abundant compounds in L. pinnatifidum, M. longifolia, O. vulgare and A. eupatoria essential oils, respectively. The current study demonstrates that M. longifolia and O. vulgare essential oils possess the potential to be used as an alternative to synthetic chemicals to protect humans from mosquito bites.
埃及伊蚊（双翅目：蚊科）是许多致病病原体的重要媒介。避免这些蚊媒疾病的一种有效方法是防止蚊子叮咬。在目前的研究中，评价了芝麻菜、薄荷、牛至和龙芽草的精油对埃及伊蚊雌蚊的驱避潜力。使用新鲜采集的植物地上部分的水蒸气蒸馏法提取精油，并通过人体诱饵技术测试其对 4-5 日龄埃及伊蚊雌蚊的驱避和驱避持续时间。通过气相色谱-质谱联用（GC-MS）探索了提取精油的化学成分。芝麻菜、薄荷、牛至和龙芽草精油在 33μg/cm 的剂量下表现出 100%、94%、87%和 83%的驱避活性。此外，薄荷和牛至精油在 165μg/cm 的剂量下表现出 100%的驱避效果，而龙芽草精油仅在 330μg/cm 的剂量下表现出 100%的驱避效果。在时间跨度生物测定中，薄荷和牛至精油对埃及伊蚊的防护作用分别持续 90 和 75 分钟，而龙芽草和芝麻菜精油则分别持续 45 分钟。苯乙腈（94%）、氧化薄荷酮（34%）、香芹酚（20%）和α-蒎烯（62%）分别是芝麻菜、薄荷、牛至和龙芽草精油中含量最丰富的化合物。本研究表明，薄荷和牛至精油具有替代合成化学品的潜力，可保护人类免受蚊子叮咬。
