Department of Chemistry, Avinashilingam Institute for Home Science and Higher Education for Women University (Estd. u/s 3 of UGC Act 1956), Coimbatore, 641043 Tamil Nadu, India.
Parasitol Res. 2012 Nov;111(5):2129-35. doi: 10.1007/s00436-012-3061-0. Epub 2012 Aug 2.
Petroleum ether, acetone, ethyl acetate, aqueous extract, methanol and ethanol fractionate of Eichhornia crassipes (Mart.) Solms was tested for their larvicidal efficacy against the different instars (I, II, III and IV) and pupae of Culex quinquefasciatus Say. The larval mortality was observed after 24 h of the treatment. The extracts showed a dose-dependent toxicity to larvae. The toxicity of the extracts decreased with increase in larval stage. Ethanol fractionate of E. crassipes showed the highest larvicidal and pupicidal activity against C. quinquefasciatus compared to other solvent extracts and fractionates with LC(50) 71.43, 94.68,120.42, 152.15 and 173.35 ppm for I, II, III, IV and pupae, respectively. Presence of metabolites like flavonoids, alkaloids, anthroquinones and anthocyanins in the tested extracts might be the reason for the larvicidal and pupicidal activity of the plant extracts and fractionates of waterhyacinth. Mosquito-repellent activity was not exhibited by these extracts at the tested concentrations. The results demonstrated the potential of the aquatic plant E. crassipes in the successful control of the filarial vector C. quinquefasciatus.
水葫芦（Eichhornia crassipes）的石油醚、丙酮、乙酸乙酯、水提物、甲醇和乙醇级分被测试其对不同龄期（I、II、III 和 IV）和蛹的致幼虫效力。在处理后 24 小时观察幼虫死亡率。提取物对幼虫表现出剂量依赖性毒性。随着幼虫阶段的增加，提取物的毒性降低。与其他溶剂提取物和馏分相比，水葫芦的乙醇馏分对库蚊表现出最高的杀幼虫和杀蛹活性，LC（50）分别为 71.43、94.68、120.42、152.15 和 173.35ppm，用于 I、II、III、IV 和蛹。在测试的提取物中存在代谢物，如类黄酮、生物碱、蒽醌和花青素，这可能是植物提取物和水葫芦馏分具有杀幼虫和杀蛹活性的原因。这些提取物在测试浓度下没有表现出驱蚊活性。结果表明，水生植物水葫芦具有成功控制丝虫病传播媒介库蚊的潜力。
