Division of Biopesticides and Environmental Toxicology, Sri Paramakalyani Centre for Excellence in Environmental Sciences, Manonmaniam Sundaranar University, Alwarkurichi, Tirunelveli, Tamil Nadu, 627 412, India.
Department of Biotechnology, St. Peter's Institute of Higher Education and Research, Avadi, Chennai, Tamil Nadu, 600 054, India.
Environ Sci Pollut Res Int. 2019 Jun;26(16):16303-16315. doi: 10.1007/s11356-019-04870-3. Epub 2019 Apr 12.
The effects of crude ethanol derived leaf extract Trichodesma indicum (Linn) (Ex-Ti) and their chief derivatives were accessed on the survival and development of the dengue mosquito Ae. aegypti also their non-toxic activity against mosquito predator. T. indicum is recognized to be the vital weed plant and a promising herb in the traditional ayurvedic medicine. In this study, the GC-MS chromatogram of Ex-Ti showed higher peak area percentage for cis-10-Heptadecenoic acid (21.83%) followed by cycloheptadecanone (14.32%). The Ex-Ti displayed predominant mortality in larvae with 96.45 and 93.31% at the prominent dosage (200 ppm) against III and IV instar. Correspondingly, sub-lethal dosage against the enzymatic profile of III and IV instar showed downregulation of α,β-carboxylesterase and SOD protein profiles at the maximum concentration of 100 ppm. However, enzyme level of GST as well as CYP450 increased significantly dependent on sub-lethal concentration. Likewise, fecundity and hatchability of egg rate of dengue mosquito decreased to the sub-lethal concentration of Ex-Ti. Repellent assay illustrates that Ex-Ti concentration had greater protection time up to 210 min at 100 ppm. Also, activity of Ex-Ti on adult mosquito displayed 100% mortality at the maximum dosage of 600, 500 and 400 ppm within the period of 50, 60 and 70 min, respectively. Photomicrography screening showed that lethal dosage of Ex-Ti (100 ppm) produced severe morphological changes with dysregulation in their body parts as matched to the control. Effects of Ex-Ti on the Toxorhynchites splendens IV instar larvae showed less mortality (43.47%) even at the maximum dosage of 1500 ppm as matched to the chemical pesticide Temephos. Overall, the present research adds a toxicological valuation on the Ex-Ti and their active constituents as a larvicidal, repellent and adulticidal agents against the global burdening dengue mosquito.
从 crude ethanol 衍生的 Trichodesma indicum（Linn）（Ex-Ti）叶提取物及其主要衍生物对登革热蚊子 Aedes aegypti 的生存和发育的影响，以及它们对蚊子捕食者的非毒性活性进行了评估。 Trichodesma indicum 被认为是一种重要的杂草植物，也是传统阿育吠陀医学中一种有前途的草药。在这项研究中，Ex-Ti 的 GC-MS 色谱图显示 cis-10-Heptadecenoic acid（21.83%）的峰面积百分比较高，其次是环十七烷酮（14.32%）。Ex-Ti 在幼虫中表现出显著的死亡率，在突出剂量（200 ppm）下对 III 和 IV 龄幼虫的死亡率分别为 96.45%和 93.31%。相应地，亚致死剂量对 III 和 IV 龄幼虫的酶谱显示，在最大浓度 100 ppm 时，α、β-羧酸酯酶和 SOD 蛋白谱下调。然而，GST 和 CYP450 的酶水平随着亚致死浓度的增加而显著增加。同样，登革热蚊子的产卵率和孵化率也降低到亚致死浓度的 Ex-Ti。驱避剂试验表明，Ex-Ti 浓度在 100 ppm 时具有长达 210 分钟的更大保护时间。此外，Ex-Ti 对成蚊的活性在最大剂量为 600、500 和 400 ppm 时，在 50、60 和 70 分钟内分别显示出 100%的死亡率。光镜筛选表明，致死剂量的 Ex-Ti（100 ppm）产生了严重的形态变化，与对照相比，其身体部位的调节失调。Ex-Ti 对 Toxorhynchites splendens IV 龄幼虫的影响显示，即使在最大剂量为 1500 ppm 时，死亡率也较低（43.47%），与化学农药 Temephos 相比。总的来说，本研究对 Ex-Ti 及其活性成分作为一种杀幼虫、驱避和杀成虫剂对抗全球登革热蚊子进行了毒理学评估。
