氯嘧磺隆降解菌L-6的分离鉴定及其降解特性

Isolation Identification and Degradation Characteristics of Chlorimuron-ethyl Degradation Bacteria L-6

从氯嘧磺隆污染的土壤中筛选分离出能够降解氯嘧磺隆的菌株,研究其降解特性。为氯嘧磺隆污染土壤的生物修复提供理论依据。利用富集培养技术从长期施用氯嘧磺隆的土壤中分离得到1株能够降解氯嘧磺隆的细菌,命名为L-6。通过对该菌株形态特征观察,生理生化特性和16SrDNA序列分析,初步鉴定菌株L-6为恶臭假单胞菌(Pseudomonas putida)。并分析了氯嘧磺隆的初始浓度、接种量、温度和pH对菌株L-6和降解氯嘧磺隆效果的影响,确定了最佳降解条件。结果显示,菌株L-6在氯嘧磺隆浓度为200mg/L、接种量为10%、pH8.0、温度30℃条件下,接种4天后对氯嘧磺隆的降解效率达到80%以上。这表明菌株L-6具有降解氯嘧磺隆的潜在应用价值。

In order to provide the theoretic basis in bioremediation of chlorimuron-ethyl-contaminated soil, a chlorimuron-ethyl degradable strain was obtained from chlorimuron-ethyl-contaminated soil. L-6, a bacterium which was able to degrade chlorimuron-ethyl, was isolated from the soil of long term applied with chlorimuron-ethyl by enrichment culture. Based on morphology observation, physiological and biochemical characteristics, 16S rDNA sequence analysis, the strain L-6 was identified preliminarily as Pseudomonas putida. The effect of initial concentration of chlorimuron-ethyl, inoculation amount, temperature and pH on degradation efficiencies was studied. The optimal degrading conditions were： initial concentration of chlorimuron-ethyl 200 mg/L, inoculation amount of 10%, pH 8.0, respectively, under the optimal conditions, the degrading efficiency could reach more than 80% after 4 days at 30℃. These results indicated that the strain L-6 had certain potential of degrading chlorimuron-ethyl.