Guangdong Province Key Laboratory of Microbial Signals and Disease Control, Integrative Microbiology Research Centre, College of Plant Protection, South China Agricultural University, Guangzhou, 510642, China.
Environ Geochem Health. 2024 Jul 31;46(9):356. doi: 10.1007/s10653-024-02136-7.
Acetochlor is a selective pre-emergent herbicide that is widely used to control annual grass and broadleaf weeds. However, due to its stable chemical structure, only a small portion of acetochlor exerts herbicidal activity in agricultural applications, while most of the excess remains on the surfaces of plants or enters ecosystems, such as soil and water bodies, causing harm to the environment and human health. In recent years, researchers have become increasingly focused on the repair of acetochlor residues. Compared with traditional physical and chemical remediation methods, microorganisms are the most effective way to remediate chemical pesticide pollution, such as acetochlor, because of their rich species, wide distribution, and diverse metabolic pathways. To date, researchers have isolated and identified many high-efficiency acetochlor-degrading strains, such as Pseudomonas oleovorans, Klebsiella variicola, Bacillus subtilus, Rhodococcus, and Methylobacillus, among others. The microbial degradation pathways of acetochlor include dechlorination, hydroxylation, N-dealkylation, C-dealkylation, and dehydrogenation. In addition, the microbial enzymes, including hydrolase (ChlH), debutoxylase (Dbo), and monooxygenase (MeaXY), responsible for acetochlor biodegradation are also being investigated. In this paper, we review the migration law of acetochlor in the environment, its toxicity to nontarget organisms, and the main metabolic methods. Moreover, we summarize the latest progress in the research on the microbial catabolism of acetochlor, including the efficient degradation of microbial resources, biodegradation metabolic pathways, and key enzymes for acetochlor degradation. At the end of the article, we highlight the existing problems in the current research on acetochlor biodegradation, provide new ideas for the remediation of acetochlor pollution in the environment, and propose future research directions.
乙草胺是一种选择性芽前除草剂，广泛用于防治一年生禾本科杂草和阔叶杂草。然而，由于其化学结构稳定，只有一小部分乙草胺在农业应用中发挥除草活性，而大部分过剩的乙草胺则残留在植物表面或进入生态系统，如土壤和水体，对环境和人类健康造成危害。近年来，研究人员越来越关注乙草胺残留的修复。与传统的物理和化学修复方法相比，微生物是修复化学农药污染（如乙草胺）最有效的方法，因为它们具有丰富的物种、广泛的分布和多样的代谢途径。迄今为止，研究人员已经分离和鉴定了许多高效的乙草胺降解菌株，如假单胞菌、产酸克雷伯氏菌、枯草芽孢杆菌、红球菌和甲基杆菌等。乙草胺的微生物降解途径包括脱氯、羟化、N-脱烷基化、C-脱烷基化和脱氢。此外，负责乙草胺生物降解的微生物酶，包括水解酶（ChlH）、脱丁氧基酶（Dbo）和单加氧酶（MeaXY），也在研究中。本文综述了乙草胺在环境中的迁移规律、对非靶标生物的毒性以及主要的代谢方法。此外，总结了乙草胺微生物代谢研究的最新进展，包括高效降解微生物资源、生物降解代谢途径和乙草胺降解的关键酶。文章最后，突出了当前乙草胺生物降解研究中存在的问题，为环境中乙草胺污染的修复提供了新的思路，并提出了未来的研究方向。
