Key Laboratory of South Subtropical Fruit Biology and Genetic Resource Utilization (MOA), Guangdong Province Key Laboratory of Tropical and Subtropical Fruit Tree Research, Institute of Fruit Tree Research, Guangdong Academy of Agricultural Sciences, Guangzhou 510640, China.
Institute of Traditional Chinese Medicine & Natural Products, College of Pharmacy and Guangdong Province Key Laboratory of Pharmacodynamic Constituents of TCM & New Drugs Research, Jinan University, Guangzhou, Guangdong 510632, China.
Ecotoxicol Environ Saf. 2021 Jan 15;208:111647. doi: 10.1016/j.ecoenv.2020.111647. Epub 2020 Nov 18.
Eurycomanone is a quassinoid compound that is derived from Eurycoma longifolia, and it is often used as an indicator to evaluate the active ingredients of Eurycoma longifolia. However, Eurycomanone has rarely been reported to have biological activity toward pests. In this study, we evaluated the antifeedant activity of eurycomanone against the diamondback moth(Plutella xylostella), with a non-selective AFC(the concentration that corresponds to 50% antifeedant action) value and selective AFC of 17.5 mg/L and 14.2 mg/L, respectively, which were 2.1-fold (36.9 mg/L) and 2-fold (28.5 mg/L) lower than that of azadirachtin, respectively. In addition, eurycomanone was used to treat the roots of Brassica chinensis L. at a concentration of 100 µg/g for 72 h. The antifeedant index was found to reach 93% by tracking the leaves. After feeding with 20 µg/g eurycomanone, no pupae or eclosion were observed. To explore this mechanism, we used scanning electron microscopy to discover that eurycomanone could prevent the development of taste receptors on the maxillary palp of diamondback moth larvae. Additional electrophysiological measurements showed that eurycomanone exhibited excitatory action to the central taste neurons of diamondback moth and significantly inhibited the GABA receptor current. Eurycomanone exhibited significant activity as an antifeedant, inhibited growth and excelled at systemic absorption.
莪术酮是一种从长叶莪术中提取的三萜类化合物，常被用作评价长叶莪术活性成分的指标。然而，莪术酮在害虫方面的生物活性鲜有报道。在这项研究中，我们评估了莪术酮对小菜蛾（Plutella xylostella）的拒食活性，其非选择性 AFC（对应 50%拒食活性的浓度）值和选择性 AFC 值分别为 17.5 mg/L 和 14.2 mg/L，分别比印苦素低 2.1 倍（36.9 mg/L）和 2 倍（28.5 mg/L）。此外，莪术酮以 100 µg/g 的浓度处理甘蓝根 72 h，其拒食指数达到 93%。通过跟踪叶片发现，当喂食 20 µg/g 莪术酮时，没有观察到蛹或羽化。为了探索这种机制，我们使用扫描电子显微镜发现莪术酮可以阻止小菜蛾幼虫下颚须上味觉感受器的发育。此外，电生理测量表明，莪术酮对小菜蛾中央味觉神经元表现出兴奋作用，并显著抑制 GABA 受体电流。莪术酮表现出显著的拒食活性，抑制生长并具有出色的全身吸收能力。
