The present study was aimed to check the mosquitocidal activity of intracellular methanol extract fractions and the compound di (2-ethylhexyl) phthalate isolated from Streptomyces rimosus. The isolated compound was also analyzed for its interaction with Acetylcholinesterase (AChE1). The larvae and eggs of Culex quinquefasciatus were exposed to four different concentrations such as 2.5, 5.0, 7.5 and 10 ppm for fractions and 0.5, 1.0, 1.5 and 2.0 ppm for compound. After 24 and 120 h post treatment, the larval mortality and ovicidal activity were recorded. Fractions collected from the intracellular methanol extract were tested for larvicidal activity; among them Fraction 4 was found to be the active fraction. Fraction 4 showed 74% larvicidal activity with LC₅₀ and LC₉₀ values of 6.9 and 17.2 ppm, respectively, in 24 h against the larvae of Cx. quinquefasciatus. Fraction 4 showed 95% ovicidal activity at 10 ppm concentration after 120 h post treatment. The eluted compound di(2-ethylhexyl) phthalate was highly toxic and exhibited promising activity against the eggs of Cx. quinquefasciatus. The compound presented 94% ovicidal activity at 2.0 ppm concentration after 120 h post treatment. The larvae of Cx. quinquefasciatus were exposed to di(2-ethylhexyl) phthalate which showed good activity in a concentration-dependent manner. The compound showed 76% larvicidal activity against the larvae of Cx. quinquefasciatus with LC₅₀ and LC₉₀ values of 1.22 and 3.28 ppm, respectively, at 2 ppm concentration in 24 h. Fraction 4 and the compound were subjected to toxicity study against non-target organism and were found to be nontoxic. The present studies revealed that the treated larvae showed serious damage in the midgut cells. Growth disruption and larval deformities were observed in compound-treated larvae. The compound was highly active and inhibited AChE in a concentration-dependent manner. Computational analysis of the compound had strong interaction with AChE1 of Cx. quinquefasciatus. These results clearly showed that Fraction 4 and the compound isolated from S. rimosus can be used to control the life stages of Cx. quinquefasciatus; it will be a good alternative to synthetic insecticides.

本研究的目的是检查细胞内甲醇提取物级分和从链霉菌中分离出的邻苯二甲酸二（2-乙基己基）酯的灭蚊活性。还分析了分离的化合物与乙酰胆碱酯酶（ AChE1 ）的相互作用。库蚊（Culex quinquefasciatus）的幼虫和卵将其暴露于四种不同浓度下，例如馏分的浓度为2.5、5.0、7.5和10 ppm，化合物的浓度为0.5、1.0、1.5和2.0 ppm。治疗后24小时和120小时，记录幼虫死亡率和杀卵活性。测试从细胞内甲醇提取物中收集的馏分的杀幼虫活性；其中，馏分4被发现是有效馏分。馏分4表现出74％的杀幼虫活性，在24小时内对Cx幼虫的LC ₅₀和LC ₉₀值分别为6.9和17.2 ppm 。quinquefasciatus。处理后120小时后，级分4在10 ppm浓度下显示出95％的杀卵活性。洗脱的邻苯二甲酸二（2-乙基己基）酯化合物具有很高的毒性，并且对卵的卵显示出有希望的活性。Cx。quinquefasciatus。处理后120小时后，该化合物在2.0 ppm浓度下具有94％的杀卵活性。Cx的幼虫。将奎克法西亚斯暴露于邻苯二甲酸二（2-乙基己基）酯，该邻苯二甲酸二（2-乙基己基）酯以浓度依赖性方式显示出良好的活性。该化合物对Cx的幼虫显示出76％的杀幼虫活性。LC ₅₀和LC _90的奎克筋膜在24小时内，浓度为2 ppm时，该值分别为1.22和3.28 ppm。对级分4和化合物进行了针对非靶标生物的毒性研究，发现它们是无毒的。目前的研究表明，处理过的幼虫在中肠细胞中显示出严重的损伤。在化合物处理的幼虫中观察到生长破坏和幼虫畸形。该化合物具有很高的活性，并以浓度依赖的方式抑制了AChE。该化合物的计算分析与Cx的AChE1有很强的相互作用。quinquefasciatus。这些结果清楚地表明，级分4和从利莫链霉菌中分离出的化合物可用于控制Cx的生命阶段。quinquefasciatus ; 这将是合成杀虫剂的良好替代品。