Campus Centro-Oeste Dona Lindu, Universidade Federal de São João del Rei, Av. Sebastião Gonçalves Coelho, 400 Divinópolis 35501-296, MG, Brazil.
Departamento de Biologia Geral, Universidade Federal de Viçosa, Brazil.
Ecotoxicol Environ Saf. 2018 Jun 15;154:1-5. doi: 10.1016/j.ecoenv.2018.02.009. Epub 2018 Feb 12.
The Culex quinquefasciatus mosquito is a vector of several diseases, and its control has been performed with synthetic insecticides, which may have human and environmental side effects. Thus, the use of new and safe molecules are important, and this study evaluated the toxicity of active substances against this mosquito. The oleic, linoleic, linolenic, palmitic and stearic acids and their respective methyl esters were tested against fourth instar C. quinquefasciatus larvae. Oleic, linoleic and linolenic acids had LC50 values of 8.58, 10.04 and 19.78 mg/L, respectively. Histological analysis showed that these three compounds caused cell instability with an increase in the number of vesicles in the fat body and in the midgut cells. Based on these results, glucose, triglyceride, and protein levels were evaluated after 1 h of acid exposure. These compounds decreased in insects treated with linoleic acid. Linolenic acid also caused a significant increase in acetylcholinesterase activity. These results show that oleic, linoleic, and linoleic acids have a lower LC50 for C. quinquefasciatus, affecting its metabolism and the morphology of midgut and fat body.
致倦库蚊是几种疾病的传播媒介，其防治一直采用合成杀虫剂，但可能对人类和环境有副作用。因此，使用新的安全分子非常重要，本研究评估了这些物质对这种蚊子的毒性。对第四龄期致倦库蚊幼虫进行了测试，测试物质为油酸、亚油酸、亚麻酸、棕榈酸和硬脂酸及其相应的甲酯。油酸、亚油酸和亚麻酸的 LC50 值分别为 8.58、10.04 和 19.78 mg/L。组织学分析表明，这三种化合物导致细胞不稳定，脂肪体和中肠细胞中的囊泡数量增加。基于这些结果，在酸暴露 1 小时后评估了葡萄糖、甘油三酯和蛋白质水平。在亚油酸处理的昆虫中，这些化合物减少。亚麻酸还导致乙酰胆碱酯酶活性显著增加。这些结果表明，油酸、亚油酸和亚麻酸对致倦库蚊的 LC50 较低，影响其新陈代谢以及中肠和脂肪体的形态。
