Centre of Advanced Study in Marine Biology, Annamalai University, Parangipettai, 608 502 Tamil Nadu, India.
Parasitol Res. 2011 Oct;109(4):1107-12. doi: 10.1007/s00436-011-2353-0. Epub 2011 Apr 7.
Emergence of resistance among mosquitoes is a recent problem. Safe and eco-friendly agents from biological origins are the need of the hour. Nereistoxin, a naturally occurring substance, was first isolated from the marine annelid Lumbriconereis heteropoda and stored in the freezer. In the present study, the toxicity of nereistoxin was evaluated against vector mosquitoes. The larvicidal, ovicidal and adulticidal activities of nereistoxin were assayed for their toxicity against three important vector mosquitoes, viz., Anopheles stephensi, Aedes aegypti and Culex quinquefasciatus (Diptera: Culicidae). The nereistoxin was inversely proportional to the concentration and directly proportional to the mosquitoes. The larvicidal activity after 24 h LC(50) value was observed at 0.467, 0.535 and 0.601 ppm for A. stephensi, A. aegypti and C. quinquefasciatus, respectively. The ovicidal activity after 120 h zero percentage of egg hatchability was observed at a concentration of 0.8 ppm for A. stephensi and 1.0 ppm for A. aegypti and C. quinquefasciatus. The results of the adulticidal activity after 24 h LD(50) value were observed at 0.022, 0.028 and 0.034 ppm for A. stephensi, A. aegypti and C. quinquefasciatus, respectively. The extracted nereistoxin was characterized and identified by ultraviolet, infrared, nuclear magnetic resonance, mass spectroscopic methods and high pressure liquid chromatography. These results clearly reveal that the nereistoxin served as a potential larvicidal, ovicidal and adulticidal activity against vector mosquitoes.
蚊子抗药性的出现是一个近期问题。安全且环保的生物源制剂是当前的需求。纳雷毒素是一种天然存在的物质，最初从海洋环节动物 Lumbriconereis heteropoda 中分离出来，并储存在冰箱中。在本研究中，评估了纳雷毒素对病媒蚊子的毒性。测定了纳雷毒素对三种重要病媒蚊子，即致倦库蚊、埃及伊蚊和三带喙库蚊（双翅目：蚊科）的幼虫、卵和成虫的毒力。纳雷毒素的杀虫活性与浓度成反比，与蚊子成正比。24 h 后观察到的致死中浓度（LC50）值分别为 0.467、0.535 和 0.601 ppm，用于 A. stephensi、A. aegypti 和 C. quinquefasciatus。120 h 后观察到的致卵孵化零活性的杀卵活性浓度分别为 0.8 ppm 用于 A. stephensi 和 1.0 ppm 用于 A. aegypti 和 C. quinquefasciatus。24 h 后致死中浓度（LD50）值的成虫杀虫活性结果分别为 0.022、0.028 和 0.034 ppm，用于 A. stephensi、A. aegypti 和 C. quinquefasciatus。用紫外、红外、核磁共振、质谱和高压液相色谱法对提取的纳雷毒素进行了表征和鉴定。这些结果清楚地表明，纳雷毒素对病媒蚊子具有潜在的杀虫、杀卵和杀成虫活性。
