Dong Thap University, 783 Pham Huu Lau Street, Cao Lanh City, Dong Thap Province, Vietnam.
Institute of Biotechnology, Vietnam Academy of Science and Technology, Hanoi, Vietnam.
Curr Microbiol. 2021 Dec 14;79(1):11. doi: 10.1007/s00284-021-02685-5.
Diuron, a phenylurea herbicide, has been extensively applied in controlling a wide range of weeds in several crops. In the current study, a mixed culture of three bacterial strains, i.e., Bacillus subtilis DU1, Acinetobacter baumannii DU, and Pseudomonas sp. DUK, isolated from sugarcane soil, completely degraded diuron and 3,4-DCA in liquid media at 20 mg L within 48 h. During diuron degradation, a few metabolites (DCPMU, DCPU, and 3,4-DCA) were produced. Further determination of ring-cleavage pathways demonstrated that Acinetobacter baumannii DU and Pseudomonas fluorescens DUK degraded diuron and 3,4-DCA via ortho-cleavage. In contrast, Bacillus subtilis DU transformed these compounds via meta-cleavage pathways. Moreover, diuron caused a significant shift in the bacterial community in soil without diuron history. The augmentation of mountain soil with the isolated bacteria resulted in nearly three times higher degradation rate of diuron than the degradation by indigenous microorganisms. This study provides important information on in situ diuron bioremediation from contaminated sites by bioaugmentation with a mixed bacterial culture.
敌草隆是一种苯脲类除草剂，已被广泛应用于控制多种作物中的多种杂草。在本研究中，从甘蔗土壤中分离得到的三株细菌混合培养物，即枯草芽孢杆菌 DU1、鲍曼不动杆菌 DU 和荧光假单胞菌 DUK，能够在 20mg/L 的液体培养基中在 48 小时内完全降解敌草隆和 3,4-DCA。在敌草隆降解过程中，产生了一些代谢物（DCPMU、DCPU 和 3,4-DCA）。进一步确定环裂解途径表明，鲍曼不动杆菌 DU 和荧光假单胞菌 DUK 通过邻位裂解途径降解敌草隆和 3,4-DCA。相比之下，枯草芽孢杆菌 DU 通过间位裂解途径转化这些化合物。此外，敌草隆的存在导致土壤中细菌群落发生显著变化，而这些细菌在没有敌草隆历史的土壤中也能被降解。与土著微生物相比，向山地土壤中添加分离得到的细菌可使敌草隆的降解速率提高近 3 倍。本研究为通过混合细菌培养物的生物强化原位修复污染场地中的敌草隆提供了重要信息。
