Faculty of Agriculture, Shizuoka University, 836 Ohya, Suruga-ku, Shizuoka 422-8529, Japan.
Department of Nutrition, Kohshien University, 10-1 Momijigaoka, Takarazuka 665-0006, Japan.
J Hazard Mater. 2017 Jan 5;321:586-590. doi: 10.1016/j.jhazmat.2016.09.049. Epub 2016 Sep 22.
Clothianidin (CLO) is a member of the neonicotinoid pesticides, which have been widely used worldwide over the last two decades. However, its toxicity for bees and neurological toxicity for humans are urgent problems. Here, the degradation of CLO by the white-rot fungus Phanerochaete sordida was examined in nitrogen-limited liquid medium. After incubation for 20days at 30°C, 37% of CLO was degraded in the cultures. High-resolution ESI-MS and NMR analyses of the culture supernatant identified N-(2-chlorothiazol-5-yl-methyl)-N'-methylurea (TZMU) as a metabolite of CLO degradation. The addition of cytochrome P450 inhibitors to the culture medium markedly reduced the degradation of CLO by P. sordida. And manganese peroxidase, a major ligninolytic enzyme secreted by this fungus, were not carried out CLO degradation. The effects of CLO and TZMU on the viability of the neuronal cell line Neuro2a demonstrated that P. sordida effectively degrades CLO into a metabolite that lacks neurotoxicity.
氯噻啉(CLO)是新烟碱类杀虫剂的成员,在过去二十年中已在全球范围内广泛使用。然而,其对蜜蜂的毒性和对人类的神经毒性是亟待解决的问题。本研究在氮限制的液体培养基中考察了白腐真菌糙皮侧耳对氯噻啉的降解。在 30°C 下培养 20 天后,培养物中 37%的 CLO 被降解。对培养上清液的高分辨 ESI-MS 和 NMR 分析鉴定出 N-(2-氯噻唑-5-基甲基)-N'-甲基尿(TZMU)为 CLO 降解的代谢物。向培养基中添加细胞色素 P450 抑制剂可显著降低 CLO 被糙皮侧耳的降解。而锰过氧化物酶,该真菌分泌的主要木质素降解酶,未进行 CLO 降解。CLO 和 TZMU 对神经元细胞系 Neuro2a 活力的影响表明,糙皮侧耳可有效将 CLO 降解为一种无神经毒性的代谢物。