Karthi Sengodan, Vasantha-Srinivasan Prabhakaran, Ganesan Raja, Ramasamy Venkatachalam, Senthil-Nathan Sengottayan, Khater Hanem F, Radhakrishnan Narayanaswamy, Amala Kesavan, Kim Tae-Jin, El-Sheikh Mohamed A, Krutmuang Patcharin
Division of Bio Pesticides and Environmental Toxicology, Sri Paramakalyani Centre for Excellence in Environmental Sciences, Manonmaniam Sundaranar University, Alwarkurichi, Tirunelveli 627412, Tamil Nadu, India.
Department of Biotechnology, Peter's Institute of Higher Education and Research, Avadi, Chennai 600054, Tamil Nadu, India.
J Fungi (Basel). 2020 Sep 29;6(4):196. doi: 10.3390/jof6040196.
The present investigation aimed to determine the fungal toxicity of (My-It) against the dengue mosquito vector L. and its non-target impact against the aquatic predator . Lethal concentrations (LC and LC) of My-It were observed in 2.27 and 2.93 log ppm dosages, respectively. The sub-lethal dosage (My-It-1 × 10 conidia/mL) displayed a significant oviposition deterrence index and also blocked the fecundity rate of dengue mosquitos in a dose-dependent manner. The level of major detoxifying enzymes, such as carboxylesterase (α-and β-) and SOD, significantly declined in both third and fourth instar larvae at the maximum dosage of My-It 1 × 10 conidia/mL. However, the level of glutathione S-transferase (GST) and cytochrome P-450 (CYP450) declined steadily when the sub-lethal dosage was increased and attained maximum reduction in the enzyme level at the dosage of My-It (1 × 10 conidia/mL). Correspondingly, the gut-histology and photomicrography results made evident that My-It (1 × 10 conidia/mL) heavily damaged the internal gut cells and external physiology of the dengue larvae compared to the control. Moreover, the non-target toxicity against the beneficial predator revealed that My-It at the maximum dosage (1 × 10 conidia/mL) was found to be less toxic with <45% larval toxicity against . Thus, the present toxicological research on showed that it is target-specific and a potential agent for managing medically threatening arthropods.
本研究旨在确定（My-It）对登革热蚊媒白纹伊蚊的真菌毒性及其对水生捕食者的非靶标影响。分别在2.27和2.93 log ppm剂量下观察到My-It的致死浓度（LC和LC）。亚致死剂量（My-It-1×10分生孢子/mL）显示出显著的产卵抑制指数，并且还以剂量依赖的方式阻断了登革热蚊子的繁殖率。在My-It 1×10分生孢子/mL的最大剂量下，三龄和四龄幼虫体内主要解毒酶如羧酸酯酶（α-和β-）和超氧化物歧化酶的水平显著下降。然而，当亚致死剂量增加时，谷胱甘肽S-转移酶（GST）和细胞色素P-450（CYP450）的水平稳步下降，并在My-It剂量（1×10分生孢子/mL）时达到酶水平的最大降低。相应地，肠道组织学和显微照片结果表明，与对照相比，My-It（1×10分生孢子/mL）严重损害了登革热幼虫的肠道内部细胞和外部生理。此外，对有益捕食者的非靶标毒性表明，最大剂量（1×10分生孢子/mL）的My-It对其毒性较小，幼虫毒性<45%。因此，目前对My-It的毒理学研究表明，它具有靶标特异性，是管理医学上有威胁的节肢动物的潜在药剂。
