Insect growth regulators (IGRs) are attractive alternatives to chemical insecticides. Since it has been reported that secondary metabolites from actinomycetes show insecticidal activities against various insect pests, actinomycetes could be a potential source of novel IGR compounds. In the present study, insect juvenile hormone antagonists (JHANs) were identified from actinomycetes and their insect growth regulatory and insecticidal activities were investigated. A total of 363 actinomycetes were screened for their insect growth regulatory and insecticidal activities against Aedes albopictus and Plutella xylostella. Among them, Streptomyces sp. AN120537 showed the highest JHAN and insecticidal activities. Five antimycins were isolated as active compounds by assay-guided fractionation and showed high JHAN activities. These antimycins also exhibited significant insecticidal activities against A. albopictus, P. xylostella, F. occidentalis, and T. urticae. Moreover, dead larvae treated with these antimycins displayed morphological deformities that are similar to those of JH-based IGR-treated insects. This is the first report demonstrating that the insecticidal activities of antimycins resulted from their possible JHAN activity. Based on our results, it is expected that novel JHAN compounds potentially derived from actinomycetes could be efficiently applied as IGR insecticides with a broad insecticidal spectrum.

中文翻译：

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从放线菌中分离和鉴定昆虫生长调节物质。

昆虫生长调节剂（IGR）是化学杀虫剂的有吸引力的替代品。由于据报道放线菌的次生代谢产物对各种害虫显示出杀虫活性，因此放线菌可能是新型IGR化合物的潜在来源。在本研究中，从放线菌中鉴定了昆虫少年激素拮抗剂（JHANs），并研究了它们的昆虫生长调节和杀虫活性。筛选了总共363种放线菌对白纹伊蚊和小菜蛾的昆虫生长调节和杀虫活性。其中，链霉菌属。AN120537表现出最高的JHAN和杀虫活性。通过测定指导的分离分离了五种抗霉素作为活性化合物，并显示出较高的JHAN活性。这些抗霉素还显示出对白术曲霉，小菜蛾，西方球菌和荨麻疹的显着杀虫活性。此外，用这些抗霉素处理的死幼虫显示出与基于JH的IGR处理的昆虫相似的形态变形。这是首次证明抗霉素的杀虫活性是由其可能的JHAN活性引起的。根据我们的结果，可以预期潜在地源自放线菌的新型JHAN化合物可以有效地用作具有广泛杀虫谱的IGR杀虫剂。这是首次证明抗霉素的杀虫活性是由其可能的JHAN活性引起的。根据我们的结果，可以预期潜在地源自放线菌的新型JHAN化合物可以有效地用作具有广泛杀虫谱的IGR杀虫剂。这是首次证明抗霉素的杀虫活性是由其可能的JHAN活性引起的。根据我们的结果，可以预期潜在地源自放线菌的新型JHAN化合物可以有效地用作具有广泛杀虫谱的IGR杀虫剂。