Soonwera Mayura, Moungthipmalai Tanapoom, Aungtikun Jirapon, Sittichok Sirawut
Department of Plant Production Technology, Faculty of Agricultural Technology, King Mongkut's Institute of Technology Ladkrabang, Ladkrabang, Bangkok, 10520, Thailand.
Heliyon. 2022 Apr 27;8(5):e09346. doi: 10.1016/j.heliyon.2022.e09346. eCollection 2022 May.
Extensive uses of synthetic insecticides to control mosquito's populations have induced the insects to develop resistance against them, rendering them ineffective today. Moreover, they cause serious impacts on human health and the ecosystem. Therefore, safe and effective natural alternatives are needed. This study evaluated the larvicidal and pupicidal activities of essential oils (EOs) from and and the major constituents against and mosquitoes as well as recorded their morphological aberrations at death. The GC-MS analysis showed that trans-anethole was the major constituent of EO, and limonene was the major constituent of . EO. Both were more effective against the larvae and pupae of . than those of . . A 2.5% . EO + 2.5% trans-anethole combination showed the highest larvicidal and pupicidal effects against . and . with an LT ranging from 0.2-6.9 h. Between the two tested constituents, trans-anethole exhibited stronger larvicidal and pupicidal activities (LC ranging 2.4-3.4%) against the two tested mosquito species than d-limonene (LC ranging 2.5-3.7%). Most importantly, 5% trans-anethole, 5% d-limonene, and 2.5% . EO + 2.5% trans-anethole were more effective (LT ranging 0.1-0.3 h) than 1% (w/w) temephos (LT ranging 2.9-3.1 h). Morphological aberrations at death observed were such as color pigment and thorax shape abnormalities. To conclude, trans-anethole, d-limonene, and a combination of EO + trans-anethole, are natural compounds that not only are as effective as temephos at the time of this study, but should be also be much safer to human health.
广泛使用合成杀虫剂来控制蚊子数量已促使蚊子对其产生抗性，致使这些杀虫剂如今失效。此外，它们还对人类健康和生态系统造成严重影响。因此，需要安全有效的天然替代品。本研究评估了[两种植物名称]精油（EOs）及其主要成分对[两种蚊子名称]幼虫和蛹的杀虫活性，并记录了它们死亡时的形态畸变。气相色谱 - 质谱分析表明，反式茴香脑是[第一种植物名称]精油的主要成分，柠檬烯是[第二种植物名称]精油的主要成分。两种精油对[第一种蚊子名称]的幼虫和蛹都比[第二种蚊子名称]更有效。2.5%的[第一种植物名称]精油 + 2.5%反式茴香脑组合对[第一种蚊子名称]和[第二种蚊子名称]表现出最高的杀幼虫和杀蛹效果，致死中时（LT）范围为0.2 - 6.9小时。在两种测试成分中，反式茴香脑对两种测试蚊子种类表现出比d - 柠檬烯更强的杀幼虫和杀蛹活性（致死浓度LC范围为2.4 - 3.4%），而d - 柠檬烯的致死浓度LC范围为2.5 - 3.7%。最重要的是，5%反式茴香脑、5% d - 柠檬烯以及2.5%的[第一种植物名称]精油 + 2.5%反式茴香脑比1%（w/w）的马拉硫磷更有效（致死中时LT范围为0.1 - 0.3小时），而1%（w/w）马拉硫磷的致死中时LT范围为2.9 - 3.1小时。观察到的死亡时形态畸变包括颜色色素和胸部形状异常。总之，反式茴香脑、d - 柠檬烯以及[第一种植物名称]精油 + 反式茴香脑的组合是天然化合物，在本研究时不仅与马拉硫磷一样有效，而且对人类健康应该也更安全。
