Liu Jia, Fernandez Diana, Gao Yanjin, Pierre Silvie, Gao Yongdong, Dai Guanghui
Laboratory of Plant Health and Natural Products, School of Agriculture and Biology, Shanghai Jiao Tong University, Shanghai 200240, China.
IRD, Cirad, University of Montpellier, IPME, 911, Avenue Agropolis, CEDEX 5, 34394 Montpellier, France.
Insects. 2020 May 30;11(6):336. doi: 10.3390/insects11060336.
Our previous article demonstrated that ar-turmerone ((6S)-2-methyl-6-(4-methylphenyl)-2-hepten-4-one) extracted from L. has a significant larvicidal activity against the fourth instar larvae of . To reveal the effects of ar-turmerone on C. pipiens pallens larvae, light microscopy and transmission electron microscopy were used to observe the histological and ultrastructure changes in muscle and digestive tissues of fourth instar larvae. It was also revealed by detecting the activity of the acetylcholinesterase (AChE) enzyme and three detoxifying enzymes, including carboxylesterase (CarE), glutathione-S-transferase (GST) and Cytochrome P450 monooxidases (P450). The observation under the light microscope showed that the larvae displayed a disruption of myofibril in ventral muscle cells, the disappearance of nucleolus in the malpighian tubule cells, and the exfoliation of the brush border in midgut epithelial cells, 24 h after treatment. The observation under the transmission electron microscope displayed disorganized Z-lines in the ventral muscle cells, and dissolved membrane of mitochondria, nuclear and endoplasmic reticulum in abdominal cells. The enzymatic activity results showed that ar-turmerone significantly increased the level of detoxifying enzymes, while the activity of AChE was not obviously affected. All the results suggest that the larvicidal mechanism of ar-turmerone is estimated to be stomach poison and the active sites might be the muscle and digestive tissues, and the mode of action of ar-turmerone may be unrelated to AChE.
我们之前的文章表明，从[植物名称]中提取的莪术二酮（(6S)-2-甲基-6-(4-甲基苯基)-2-庚烯-4-酮）对[蚊虫名称]的四龄幼虫具有显著的杀幼虫活性。为了揭示莪术二酮对淡色库蚊幼虫的影响，利用光学显微镜和透射电子显微镜观察了四龄幼虫肌肉和消化组织的组织学和超微结构变化。还通过检测乙酰胆碱酯酶（AChE）以及三种解毒酶（包括羧酸酯酶（CarE）、谷胱甘肽-S-转移酶（GST）和细胞色素P450单加氧酶（P450））的活性进行了研究。光学显微镜观察显示，处理24小时后，幼虫腹侧肌肉细胞中的肌原纤维遭到破坏，马氏管细胞中的核仁消失，中肠上皮细胞的刷状缘脱落。透射电子显微镜观察显示，腹侧肌肉细胞中的Z线排列紊乱，腹部细胞中的线粒体、细胞核和内质网的膜溶解。酶活性结果表明，莪术二酮显著提高了解毒酶的水平，而AChE的活性未受到明显影响。所有结果表明，莪术二酮的杀幼虫机制估计为胃毒作用，作用部位可能是肌肉和消化组织，且莪术二酮的作用方式可能与AChE无关。
