Akhtar Javeria, Khan Aiman, Mustafa Hina, Ikram Aqsa, Raza Faiz Ahmed, Saleem Rahman Shah Zaib, Tasadduq Raazia, Ashraf Minhaj, Khalid Ruqyya
J Am Mosq Control Assoc. 2025 Jul 8. doi: 10.2987/24-7212.
Plant-based insecticides are getting attention as an alternative mosquito control strategy because of the emergence of insect resistance to currently used synthetic chemicals. Further, their high safety profile makes them ideal candidates for environmental applications. The current study evaluated the insecticidal potential of Psidium guajava and Piper betle leaf extracts against Aedes aegypti through in vitro and in silico approaches. In laboratory studies, the LC50 of n-hexane extract of P. guajava and ethyl acetate extract of P. betle were 95.21 ppm and 217.7 ppm after 24-h exposure, respectively. The gas chromatography-mass spectrometry analysis identified important bioactive compounds, including caryophyllene (21.2%), globulol (19.9%), squalene (8.3%), and γ-muurolene (6.6%) in P. guajava and hydroxychavicol (57%), 5-allyl-2-hydroxyphenyl acetate (5.6%), phytol (2.3%), and safrole (1.8%) in P. betle extract. In silico analysis of these compounds with target proteins acetylcholinesterase (AChE), S-adenosylhomocysteine hydrolase (SAHH), and sterol carrier protein-2 (SCP-2) in Ae. aegypti larvae showed that squalene from P. guajava had a higher binding affinity with AChE (-8.4 kcal/mol) compared to globulol (-7.3 kcal/mol). However, conventional hydrogen bonding, which is stronger and more stable, was observed in the globulol-AChE complex. The in silico analysis of P. betle phytochemicals demonstrated that hydroxychavicol, phytol, and safrole had binding affinities of -6.1 kcal/mol, -6.0 kcal/mol, and -6.0 kcal/mol with SAHH, respectively. A minor increase in binding affinity was observed in the safrole-SAHH complex (-6.1 kcal/mol), whereas no change was observed in the 5-allyl-2-hydroxyphenyl acetate-AChE complex (-5.9 kcal/mol) in 2-ligand binding mode. Since these bioactive compounds target the important proteins in the developmental processes of mosquito larvae, they can further be evaluated to design natural and organic insecticides against Ae. aegypti.
由于昆虫对目前使用的合成化学物质产生抗性，植物源杀虫剂作为一种替代的蚊虫控制策略正受到关注。此外，它们的高安全性使其成为环境应用的理想选择。当前的研究通过体外和计算机模拟方法评估了番石榴叶和蒌叶提取物对埃及伊蚊的杀虫潜力。在实验室研究中，番石榴叶正己烷提取物和蒌叶乙酸乙酯提取物在暴露24小时后的半数致死浓度（LC50）分别为95.21 ppm和217.7 ppm。气相色谱 - 质谱分析鉴定出重要的生物活性化合物，包括番石榴叶中的石竹烯（21.2%）、球松素（19.9%）、角鲨烯（8.3%）和γ-依兰油烯（6.6%），以及蒌叶提取物中的羟基查耳酮（57%）、5-烯丙基-2-羟基苯乙酸酯（5.6%）、叶绿醇（2.3%）和黄樟素（1.8%）。对这些化合物与埃及伊蚊幼虫中的靶蛋白乙酰胆碱酯酶（AChE）、S-腺苷同型半胱氨酸水解酶（SAHH）和固醇载体蛋白-2（SCP-2）进行计算机模拟分析表明，番石榴叶中的角鲨烯与AChE的结合亲和力（-8.4 kcal/mol）高于球松素（-7.3 kcal/mol）。然而，在球松素 - AChE复合物中观察到更强且更稳定的传统氢键。对蒌叶植物化学物质的计算机模拟分析表明，羟基查耳酮、叶绿醇和黄樟素与SAHH的结合亲和力分别为-6.1 kcal/mol、-6.0 kcal/mol和-6.0 kcal/mol。在2-配体结合模式下，黄樟素 - SAHH复合物的结合亲和力略有增加（-6.1 kcal/mol），而5-烯丙基-2-羟基苯乙酸酯 - AChE复合物（-5.9 kcal/mol）未观察到变化。由于这些生物活性化合物靶向蚊虫幼虫发育过程中的重要蛋白质，它们可进一步评估以设计针对埃及伊蚊的天然和有机杀虫剂。
