Yagoo Alex, Milton M C John, Vilvest Jelin, Arokia Ahino Jessie A, Shirota Osamu, Balakrishna Kedike
Department of Zoology, St. Xavier's College (Autonomous), Palayamkottai, Tirunelveli, Tamil Nadu, India, 627002; PG & Research Department of Advanced Zoology & Biotechnology, Loyola College (Autonomous), Chennai, 600034, India.
PG & Research Department of Advanced Zoology & Biotechnology, Loyola College (Autonomous), Chennai, 600034, India.
Toxicon. 2025 Jan;253:108200. doi: 10.1016/j.toxicon.2024.108200. Epub 2024 Dec 5.
Mosquitoes, as hematophagous ectoparasites, are significant pests and vectors of numerous pathogens, causing diseases such as dengue, lymphatic filariasis, malaria, chikungunya, and Japanese encephalitis in India. This study investigates the potential of natural insecticides derived from plants to combat mosquito populations, focusing on botanical extract from the leave of Sphaeranthus indicus. Specifically, the hexane extract of S. indicus exhibited notable efficacy against Aedes aegypti and Culex quinquefasciatus mosquitoes. The research entailed the extraction, fractionation, and structural identification of active compounds through spectroscopic analysis. Among ten fractions isolated, fraction 4 demonstrated the highest mosquitocidal activity, leading to the identification of β-isocostic acid as the primary active compound. The study's biological assays included ovicidal, larvicidal, and pupicidal tests, revealing that β-isocostic acid exhibited significant efficacy, with ovicidal activity rates of 75.2% and 78.2% at 2 ppm against Ae. aegypti and Cx. quinquefasciatus, respectively. Larvicidal and pupicidal assays further confirmed the potent activity of β-isocostic acid, with LC values of 1.02 ppm and 0.96 ppm against Ae. aegypti and Cx. quinquefasciatus larvae, and 1.20 ppm and 1.14 ppm against Ae. aegypti and Cx. quinquefasciatus pupae respectively. The isolated compound demonstrated comparable efficacy to azadirachtin and temephos, indicating its potential as a natural mosquitocidal agent. This research underscores the importance of exploring botanical sources for developing effective and environmentally sustainable mosquito control strategies, particularly in light of increasing resistance to synthetic insecticides. The findings suggest that β-isocostic acid could serve as a viable alternative to chemical mosquitocides, contributing to integrated vector management programs.
蚊子作为吸血性外寄生虫，是重要的害虫和众多病原体的传播媒介，在印度可引发登革热、淋巴丝虫病、疟疾、基孔肯雅热和日本脑炎等疾病。本研究调查了源自植物的天然杀虫剂对抗蚊子种群的潜力，重点关注印度圆金盏菊叶子的植物提取物。具体而言，印度圆金盏菊的己烷提取物对埃及伊蚊和致倦库蚊显示出显著功效。该研究涉及通过光谱分析对活性化合物进行提取、分离和结构鉴定。在分离出的十个馏分中，馏分4表现出最高的杀蚊活性，从而鉴定出β-异贝壳杉酸为主要活性化合物。该研究的生物学测定包括杀卵、杀幼虫和杀蛹试验，结果表明β-异贝壳杉酸具有显著功效，在2 ppm浓度下对埃及伊蚊和致倦库蚊的杀卵活性率分别为75.2%和78.2%。杀幼虫和杀蛹试验进一步证实了β-异贝壳杉酸的强效活性，对埃及伊蚊和致倦库蚊幼虫的LC值分别为1.02 ppm和0.96 ppm，对埃及伊蚊和致倦库蚊蛹的LC值分别为1.20 ppm和1.14 ppm。分离出的化合物显示出与印楝素和双硫磷相当的功效，表明其作为天然杀蚊剂的潜力。这项研究强调了探索植物来源以制定有效且环境可持续的蚊虫控制策略的重要性，特别是鉴于对合成杀虫剂的抗性不断增加。研究结果表明，β-异贝壳杉酸可作为化学杀蚊剂的可行替代品，为综合病媒管理计划做出贡献。
