Chen Wen-Juan, Luo Xiaofang, Zhang Xuanrui, Bhatt Kalpana, Chen Shao-Fang, Ghorab Mohamed A, Zhou Xiaofan, Huang Yaohua
Integrative Microbiology Research Centre, College of Plant Protection, South China Agricultural University, Guangzhou, 510642, China.
Wildlife Toxicology Lab, Department of Animal Science, Institute for Integrative Toxicology (IIT), Michigan State University, East Lansing, MI, 48824, USA.
Microb Cell Fact. 2025 May 27;24(1):124. doi: 10.1186/s12934-025-02747-4.
Tetramethrin is a common pyrethroid insecticide, but there is limited knowledge about its degradation kinetics and mechanisms. In this study, a novel fungal strain, Neocosmospora sp. AF3, was obtained from pesticide-contaminated fields and was shown to be highly effective for degrading tetramethrin and other widely used pyrethroids. The AF3 strain completely removed 10 mg/L of tetramethrin from mineral salt medium in 9 days. The first-order kinetic analysis indicated that the degradation rate constant of the AF3 strain on 50 mg/L tetramethrin was 0.2835 d (per day), and the half-life was 2.45 days. A response surface model analysis showed that the optimal degradation conditions for the AF3 strain are a temperature of 33.37 ℃, pH of 7.97, and inoculation amount of 0.22 g/L dry weight. The Andrews nonlinear fitting results suggested that the optimal concentration of tetramethrin metabolized by the AF3 strain is 12.6073 mg/L, and the q, K, and K values were 0.9919 d, 20.1873 mg/L, and 7.8735 mg/L, respectively. The gas chromatography-mass spectrometry (GC-MS) analysis indicated that N-hydroxymethyl-3,4,5,6-tetrahydrophthalimide, chrysanthemic acid and tetrahydrophthalimide are the main intermediates involved in the metabolism of tetramethrin by the AF3 strain. Furthermore, this strain was shown to effectively degrade other pyrethroid pesticides including permethrin, beta-cypermethrin, chlorempenthrin, fenvalerate, D-cyphenothrin, bifenthrin, meperfluthrin, cyfluthrin, and deltamethrin within a short period, suggesting that Neocosmospora sp. AF3 can play an important role in the remediation of pyrethroid contamination. Taken together, these results shed a new light on uncovering the degradation mechanisms of tetramethrin and present useful agents for developing relevant pyrethroid bioremediation strategies.
胺菊酯是一种常见的拟除虫菊酯类杀虫剂，但关于其降解动力学和机制的了解有限。在本研究中，从受农药污染的田地中获得了一种新型真菌菌株——新宇宙孢菌AF3，该菌株被证明对降解胺菊酯和其他广泛使用的拟除虫菊酯类杀虫剂非常有效。AF3菌株在9天内从矿物盐培养基中完全去除了10mg/L的胺菊酯。一级动力学分析表明，AF3菌株对50mg/L胺菊酯的降解速率常数为0.2835d（每天），半衰期为2.45天。响应面模型分析表明，AF3菌株的最佳降解条件为温度33.37℃、pH值7.97、接种量0.22g/L干重。安德鲁斯非线性拟合结果表明，AF3菌株代谢胺菊酯的最佳浓度为12.6073mg/L，q、K和K值分别为0.9919d、20.1873mg/L和7.8735mg/L。气相色谱-质谱联用（GC-MS）分析表明，N-羟甲基-3,4,5,6-四氢邻苯二甲酰亚胺、菊酸和四氢邻苯二甲酰亚胺是AF3菌株代谢胺菊酯的主要中间产物。此外，该菌株还被证明能在短时间内有效降解其他拟除虫菊酯类农药，包括氯菊酯、高效氯氰菊酯、氯烯炔菊酯、氰戊菊酯、右旋苯醚菊酯、联苯菊酯、甲氟菊酯、氟氯氰菊酯和溴氰菊酯，这表明新宇宙孢菌AF3在拟除虫菊酯污染修复中可发挥重要作用。综上所述，这些结果为揭示胺菊酯的降解机制提供了新的线索，并为开发相关拟除虫菊酯生物修复策略提供了有用的菌株。
