Department of Zoology, University College, Thiruvananthapuram, Kerala 695034, India.
Department of Chemistry, Government College for Women, Thiruvananthapuram, Kerala 695014, India.
Pestic Biochem Physiol. 2019 Jan;153:161-170. doi: 10.1016/j.pestbp.2018.11.018. Epub 2018 Dec 8.
Oryctes rhinoceros Linn. is one of the most serious pests of coconuts and other palms. Following bioassay guided method, a larvicidal compound, 22-hydroxyhopane has been isolated for the first time from methanol extract of leaves of Adiantum latifolium Lam. against the pest (LC value 20.81 μg/g). It is a hopanoid triterpene with molecular mass of 442.42 g/mol. The compound exhibited antibacterial activity against symbiotic gut bacteria, caused histolysis of midgut tissues and inhibited secretion of digestive enzymes such as protease, amylase and trehalase resulting in weight loss of larvae. Enzyme immunoassay showed an elevation of 20-hydroxyecdysone level in haemolymph causing disruption of metamorphosis of larvae.
鳞翅目犀角金龟是椰子和其他棕榈科植物的最严重害虫之一。通过生物测定指导的方法，首次从凤尾蕨甲醇提取物中分离到一种杀幼虫化合物 22-羟基胆甾烷，对该害虫具有活性（LC 值为 20.81μg/g）。它是一种具有 442.42g/mol 分子量的霍烷三萜。该化合物表现出对共生肠道细菌的抗菌活性，导致中肠组织的组织溶解，并抑制蛋白酶、淀粉酶和海藻糖酶等消化酶的分泌，导致幼虫体重减轻。酶联免疫吸附试验显示血淋巴中 20-羟基蜕皮甾酮水平升高，导致幼虫变态中断。
