Key Laboratory for Microbiological Engineering of Agricultural Environment, Ministry of Agriculture, College of Life Sciences, Nanjing Agricultural University, Nanjing 210095, China.
J Agric Food Chem. 2010 Sep 8;58(17):9711-5. doi: 10.1021/jf101974y.
The diphenyl ether herbicide lactofen is commonly used to control broadleaf weeds. Once released into the environment, this herbicide is subject to microbial reactions. This study describes the biotransformation of lactofen by Brevundimonas sp. LY-2 isolated from enrichment cultures inoculated with soil sample. This strain degraded about 80% of 50 mg L(-1) lactofen in 5 days of incubation in flasks. The metabolic behaviors of the herbicide in the media are described. The results show a transformation pathway of lactofen by the bacterium leading to the formation of 1-(carboxy)ethyl-5-(2-chloro-4-(trifluoromethyl)phenoxy)-2-nitrobenzoate and ethanol. An esterase, which could cleave the right ester bond of the alkanoic side chain of lactofen, was purified 113.3-fold to homogeneity with 6.83% recovery. The current results suggested that Brevundimonas sp. LY-2 degraded lactofen via the ester bond cleavage catalyzed by esterase.
二苯醚类除草剂乳氟禾草灵常用于防除阔叶杂草。这种除草剂一旦释放到环境中，就会受到微生物的反应。本研究描述了从接种土壤样品的富集培养物中分离出的 Brevundimonas sp. LY-2 对乳氟禾草灵的生物转化。该菌株在摇瓶中孵育 5 天即可降解约 50mg/L 的乳氟禾草灵的 80%。描述了该除草剂在培养基中的代谢行为。结果表明，该细菌通过乳氟禾草灵的转化途径形成 1-(羧基)乙基-5-(2-氯-4-(三氟甲基)苯氧基)-2-硝基苯甲酸和乙醇。一种酯酶可以切断乳氟禾草灵烷酸侧链的正确酯键，该酯酶经纯化后比活提高了 113.3 倍，回收率为 6.83%。目前的结果表明，Brevundimonas sp. LY-2 通过酯酶催化的酯键断裂降解乳氟禾草灵。
