Larval toxicity of ethanolic extract of C. parvula (Ex-Cp) was prominent in the second and the third instars at the maximum lethal dosage of 100 ppm with 98 and 97 % mortality rate respectively. The LC50 and LC90 was displayed at 43 ppm and 88 ppm dosage respectively. Correspondingly, the sub-lethal dosage (65 ppm) of Ex-Cp significantly alters the carboxylesterase (α and β), GST and CYP450 enzyme level in both III and IV instar larvae in dose-dependent manner. Similarly, the Ex-Cp displayed significant repellent activity (97 %) with a maximum level of protection time (210 min). Photomicrography assay of Ex-Cp (65 ppm) were toxic to dengue larvae as compared to control. The non-target toxicity of Ex-Cp against the beneficial mosquito predators displayed less toxicity at the maximum dosage of 600 ppm as compared to Temephos. Thus the present research delivers the target and non-target toxicity of red algae C. parvula against the dengue mosquito vector.

中文翻译：

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针对登革热灭蚊媒介埃及伊蚊（Lied。）的海洋红藻小鳞茎（C. Agardh）的毒理学筛选及其对三种有益水生捕食者的无毒性。

在第二龄和第三龄幼虫中，小球藻乙醇提取物（Ex-Cp）的幼虫毒性显着，最大致死剂量为100 ppm，死亡率分别为98％和97％。LC50和LC90分别以43 ppm和88 ppm的剂量显示。相应地，Ex-Cp的亚致死剂量（65 ppm）以剂量依赖性方式显着改变了三龄和四龄幼虫中的羧酸酯酶（α和β），GST和CYP450酶水平。同样，Ex-Cp表现出显着的驱避活性（97％），并具有最长的保护时间（210分钟）。与对照相比，Ex-Cp（65 ppm）的显微照相法对登革幼虫有毒性。与Temephos相比，Ex-Cp对有益蚊子捕食者的非目标毒性在600 ppm的最大剂量下显示出较小的毒性。