Biology Program, School of Science, Walailak University, Nakhon Si Thammarat, Thailand.
Central Laboratory and Greenhouse Complex, Faculty of Agriculture Kamphaeng Saen, Kasetsart University, Kamphaeng Saen Campus, Nakhon Pathom 73140, Thailand.
J Econ Entomol. 2023 Aug 10;116(4):1205-1210. doi: 10.1093/jee/toad108.
Artocarpus lacucha, a plant in the Moraceae family, has traditionally been used in Southeast Asian medicine to treat various ailments. This study investigated the insecticidal potential against Spodoptera litura of several compounds extracted from A. lacucha using a topical application method. A sequential extraction method was employed with A. lacucha stems to identify the most toxic crude extract by using hexane, dichloromethane, ethyl acetate, and methanol solvents. Subsequently, the most toxic crude extract was analyzed for chemical composition by HPLC, followed by the isolation process. Among these crude extracts, the ethyl acetate crude extract was the most toxic to second-instar S. litura larvae (24-h LD50 value of ~9.07 µg/larva). Our results showed that the catechin isolated from the ethyl acetate crude extract exhibited the highest toxicity against this insect (24-h LD50 value of ~8.37 µg/larva). Additionally, catechin significantly decreased the activities of acetylcholinesterase, carboxylesterases, and glutathione S-transferase in the larvae. These findings suggest that catechin isolated from A. lacucha could be a potential insecticidal agent against S. litura. However, the toxicity and persistence of catechin under field conditions need to be further investigated to develop this novel insecticide.
面包果，一种桑科植物，在传统医学中被用于治疗各种疾病。本研究采用局部涂抹法，评估了从面包果茎中提取的几种化合物对斜纹夜蛾的杀虫潜力。采用连续提取法，用正己烷、二氯甲烷、乙酸乙酯和甲醇溶剂，从面包果茎中鉴定出毒性最大的粗提取物。然后，通过高效液相色谱法（HPLC）对毒性最大的粗提取物进行化学成分分析，随后进行分离过程。在这些粗提取物中，乙酸乙酯粗提取物对斜纹夜蛾二龄幼虫的毒性最大（24 小时 LD50 值约为 9.07 µg/幼虫）。我们的研究结果表明，从乙酸乙酯粗提取物中分离出的儿茶素对这种昆虫的毒性最高（24 小时 LD50 值约为 8.37 µg/幼虫）。此外，儿茶素显著降低了幼虫体内乙酰胆碱酯酶、羧酸酯酶和谷胱甘肽 S-转移酶的活性。这些发现表明，从面包果中分离出的儿茶素可能是一种潜在的斜纹夜蛾杀虫剂。然而，需要进一步研究儿茶素在田间条件下的毒性和持效性，以开发这种新型杀虫剂。
