Wang Yanhui, Li Honghong, Feng Guojun, Du Liangwei, Zeng Dongqiang
Institute of Pesticide and Environmental Toxicology, Guangxi University, Nanning, PR China.
Guangxi Key Laboratory of Biology for Crop Diseases and Insect Pests, Plant Protection Research Institute, Guangxi Academy of Agricultural Sciences, Nanning, PR China.
PLoS One. 2017 Aug 15;12(8):e0182556. doi: 10.1371/journal.pone.0182556. eCollection 2017.
A diuron-degrading endophyte DP8-1 was isolated from sugarcane root grown in diuron-treated soil in the present study. The endophyte was identified as Neurospora intermedia based on the morphological characteristics and sequence analysis. The fermentation parameters including temperature, pH, inoculation size, carbon source, and initial diuron concentration were also investigated for the optimization of degradation efficiency. The results indicated that strain DP8-1 was capable of degrading up to 99% diuron within 3 days under the optimal degrading condition. The study of degradation spectrum indicated that strain DP8-1 could also degrade and utilize fenuron, monuron, metobromuron, isoproturon, chlorbromuron, linuron, and chlortoluron as substrate for strain growth. On basis of liquid chromatography-mass spectrometry analysis for the products of the degradation of diuron, strain DP8-1 metabolized diuron to produce N-(3,4-dichlorophenyl)-urea and N-(3,4-dichlorophenyl)-N-methylurea through sequential N-dealkylations. In a soil bioaugmentation experiment, the inoculation of strain DP8-1 into diuron-treated soil effectively enhanced the disappearance rate of diuron.
在本研究中，从在敌草隆处理过的土壤中生长的甘蔗根中分离出一株降解敌草隆的内生菌DP8-1。基于形态特征和序列分析，该内生菌被鉴定为间型新孢菌。还研究了包括温度、pH值、接种量、碳源和初始敌草隆浓度在内的发酵参数，以优化降解效率。结果表明，在最佳降解条件下，菌株DP8-1能够在3天内降解高达99%的敌草隆。降解谱研究表明，菌株DP8-1还可以降解并利用非草隆、灭草隆、甲氧隆、异丙隆、氯溴隆、利谷隆和绿麦隆作为菌株生长的底物。基于对敌草隆降解产物的液相色谱-质谱分析，菌株DP8-1通过连续的N-脱烷基作用将敌草隆代谢为N-(3,4-二氯苯基)脲和N-(3,4-二氯苯基)-N-甲基脲。在土壤生物强化实验中，将菌株DP8-1接种到经敌草隆处理的土壤中有效地提高了敌草隆的消失速率。
