Unit of Bioactive Natural Products, Post Graduate and Research Department of Zoology, C. Abdul Hakeem College, Melvisharam, 632509 Vellore District, Tamil Nadu, India.
Parasitol Res. 2010 Jan;106(2):481-92. doi: 10.1007/s00436-009-1690-8. Epub 2009 Dec 2.
The purpose of the present study was to assess the effect of leaf hexane and chloroform extracts of Aegle marmelos, Andrographis lineata, Andrographis paniculata, Cocculus hirsutus, Eclipta prostrata, and Tagetes erecta on repellent, ovicidal, and oviposition-deterrent activities against Culex tritaeniorhynchus Giles (Diptera: Culicidae). The repellent action of the plant extracts tested varied depending on the plant species, part, solvent used in extraction, and the extract dose. The hexane extract of A. paniculata was more effective in exhibiting the repellent action against the mosquito as compared with A. lineata extract. Complete protections for 150 min were found in hexane extract of A. paniculata at 500 ppm against mosquito bites. Mean percent hatchability of the ovicidal activity was observed 24 h after treatment. The percent hatchability was inversely proportional to the concentration of extract and directly proportional to the eggs. No hatchability was observed with hexane, and chloroform extracts of A. lineata, A. paniculata, and hexane extract of T. erecta were exerted at 1,000 ppm. The percentage of effective oviposition repellency were 95.90, 94.75, 95.04, 90.58, 87.93, 87.14, 94.82, 95.71, 92.26, 90.58, 83.35, and 78.16 at 500 ppm, and the lowest repellency was 69.93, 53.06, 64.81, 70.06, 51.82, 54.54, 48.31, 66.71, 68.82, 61.85, 34.84, and 39.53 at 31.25 ppm in hexane and chloroform extracts of A. marmelos, A. lineata, A. paniculata, C. hirsutus, E. prostrata, and T. erecta, respectively. The oviposition activity index values revealed that the solvent plant extracts have deterrent effect, and they caused a remarkable negative response resulting in oviposition of very few eggs. These results clearly reveal that the hexane extracts of A. marmelos and A. paniculata served as a potential repellent, ovicidal, and oviposition deterrent against Japanese encephalitis vector, C. tritaeniorhynchus.
本研究的目的是评估 Aegle marmelos、Andrographis lineata、Andrographis paniculata、Cocculus hirsutus、Eclipta prostrata 和 Tagetes erecta 的叶正己烷和氯仿提取物对致倦库蚊（Culex tritaeniorhynchus Giles）的驱避、杀卵和产卵驱避活性的影响。测试的植物提取物的驱避作用因植物种类、部位、提取溶剂和提取物剂量而异。与 A. lineata 提取物相比，A. paniculata 的正己烷提取物在表现驱避作用方面更有效。在 500 ppm 时，A. paniculata 的正己烷提取物对蚊虫叮咬的完全保护时间长达 150 分钟。24 小时后观察到杀卵活性的平均孵化率。孵化率与提取物的浓度成反比，与卵成正比。在 1000 ppm 时，A. lineata、A. paniculata 和 T. erecta 的正己烷和氯仿提取物均未观察到孵化率。有效产卵驱避率分别为 95.90%、94.75%、95.04%、90.58%、87.93%、87.14%、94.82%、95.71%、92.26%、90.58%、83.35%和 78.16%在 500 ppm 时，最低的驱避率为 69.93%、53.06%、64.81%、70.06%、51.82%、54.54%、48.31%、66.71%、68.82%、61.85%、34.84%和 39.53%在 A. marmelos、A. lineata、A. paniculata、C. hirsutus、E. prostrata 和 T. erecta 的正己烷和氯仿提取物中。产卵活性指数值表明，溶剂植物提取物具有驱避作用，它们引起了显著的负反应，导致产卵的卵很少。这些结果清楚地表明，A. marmelos 和 A. paniculata 的正己烷提取物对日本脑炎传播媒介致倦库蚊具有潜在的驱避、杀卵和产卵驱避作用。
