Unit of Nanotechnology and Bioactive Natural Products, Post Graduate and Research Department of Zoology, C. Abdul Hakeem College, Vellore District, Tamil Nadu, India.
Asian Pac J Trop Med. 2011 Sep;4(9):698-705. doi: 10.1016/S1995-7645(11)60177-6.
To evaluate the larvicidal and repellent activities of ethyl acetate and methanol extracts of Acacia concinna (A. concinna), Cassia siamea (C. siamea), Coriandrum sativum (C. sativum),Cuminum cyminum (C. cyminum), Lantana camara (L. camara), Nelumbo nucifera (N. nucifera) Phyllanthus amarus (P. amarus), Piper nigrum (P. nigrum) and Trachyspermum ammi (T. ammi) against Anopheles stephensi (An. stephensi) and Culex quinquefasciatus (Cx. quinquefasciatus).
The larvicidal activity of medicinal plant extracts were tested against early fourth-instar larvae of malaria and filariasis vectors. The mortality was observed 24 h and 48 h after treatment, data were subjected to probit analysis to determine the lethal concentrations (LC(50) and LC(90)) to kill 50 and 90 per cent of the treated larvae of the tested species. The repellent efficacy was determined against two mosquito species at five concentrations (31.25, 62.50, 125.00, 250.00, and 500.00 ppm) under the laboratory conditions.
All plant extracts showed moderate effects after 24 h and 48 h of exposure; however, the highest activity was observed after 24 h in the leaf methanol extract of N. nucifera, seed ethyl acetate and methanol extract of P. nigrum against the larvae of An. stephensi (LC(50) = 34.76, 24.54 and 30.20 ppm) and against Cx. quinquefasciatus (LC(50) = 37.49, 43.94 and 57.39 ppm), respectively. The toxic effect of leaf methanol extract of C. siamea, seed methanol extract of C. cyminum, leaf ethyl acetate extract of N. nucifera, leaf ethyl acetate and methanol extract of P. amarus and seed methanol extract of T. ammi were showed 100% mortality against An. stephensi and Cx. quinquefasciatus after 48 h exposer. The maximum repellent activity was observed at 500 ppm in methanol extracts of N. nucifera, ethyl acetate and methanol extract of P. nigrum and methanol extract of T. ammi and the mean complete protection time ranged from 30 to 150 min with the different extracts tested.
These results suggest that the leaf and seed extracts of C. siamea, N. nucifera, P. amarus, P. nigrum and T. ammi have the potential to be used as an ideal ecofriendly approach for the control of the An. stephensi and Cx. quinquefasciatus.
评估乙酸乙酯和甲醇提取物对美丽相思树（A. concinna）、决明子（C. siamea）、芫荽（C. sativum）、孜然芹（C. cyminum）、马缨丹（L. camara）、荷花（N. nucifera）、叶下珠（P. amarus）、黑胡椒（P. nigrum）和胡芦巴（T. ammi）对按蚊（An. stephensi）和致倦库蚊（Cx. quinquefasciatus）的杀幼虫和驱避活性。
用这些药用植物提取物对疟疾和丝虫病媒介的早期四龄幼虫进行杀幼虫活性测试。处理后 24 小时和 48 小时观察死亡率，用概率分析确定杀死测试物种 50%和 90%处理幼虫的致死浓度（LC(50)和 LC(90)）。在实验室条件下，用五种浓度（31.25、62.50、125.00、250.00 和 500.00 ppm）对两种蚊子进行驱避效果测试。
所有植物提取物在暴露 24 小时和 48 小时后均显示出中等作用；然而，在 24 小时后，N. nucifera 的叶甲醇提取物、P. nigrum 的种子乙酸乙酯和甲醇提取物对按蚊幼虫（LC(50) = 34.76、24.54 和 30.20 ppm）和致倦库蚊幼虫（LC(50) = 37.49、43.94 和 57.39 ppm）的活性最高。C. siamea 的叶甲醇提取物、C. cyminum 的种子甲醇提取物、N. nucifera 的叶乙酸乙酯提取物、P. amarus 的叶乙酸乙酯和甲醇提取物以及 T. ammi 的种子甲醇提取物对按蚊和致倦库蚊的致死率均为 100%，48 小时后暴露。N. nucifera 的甲醇提取物、P. nigrum 的乙酸乙酯和甲醇提取物以及 T. ammi 的甲醇提取物在 500 ppm 时表现出最大的驱避活性，用不同提取物测试的平均完全保护时间范围为 30 至 150 分钟。
这些结果表明，C. siamea、N. nucifera、P. amarus、P. nigrum 和 T. ammi 的叶和种子提取物具有作为控制按蚊和致倦库蚊的理想生态友好方法的潜力。
