第 53 卷第 3 期 Vol. 53 No. 3 2023 年 6 月 Jun 2023

所属栏目：安全与环保 一株嘧啶降解菌的筛选、鉴定及其降解特性

赵振华，邵汝英，高 峰，李梦琳 （江苏蓝必盛化工环保股份有限公司，江苏 宜兴 214200）

摘　要：采用梯度分批驯化的方法，从农药废水生化处理活性污泥中分离获得一株嘧啶高效降解菌LBQ-M5，该菌株能以嘧啶为唯一碳源和氮源生长。经16S rDNA序列分析，鉴定为大洋芽孢杆菌，16S rDNA序列的系统发育分析表明，菌株LBQ-M5与伊平屋桥大洋芽孢杆菌的系统发育关系最为密切，序列相似性为99.87%。结果表明，菌株LBQ-M5在温度25~40 ℃、pH=6.5~9.0、摇床转速150~250 r/min的条件下，均能高效降解嘧啶，在优化降解条件：温度30 ℃、pH=7.0、摇床转速150 r/min，初始嘧啶浓度为500 mg/L时，该菌株在24 h内的嘧啶降解率可接近100%；1 000 mg/L嘧啶在36 h降解率接近100%；1 500 mg/L嘧啶在48 h降解率为99.8%；2 000 mg/L嘧啶在72 h降解率可达98.9%。菌株盐分耐受实验表明，在盐度（NaCl质量分数）为0.5%~2.5%时，菌株LBQ-M5可高效降解嘧啶，24 h对500 mg/L嘧啶降解率为100%；盐度在3.5%时，嘧啶降解率仍有91.2%；表明菌株LBQ-M5属于中度耐盐菌。

关键词：嘧啶；大洋芽孢杆菌；生物降解

中图分类号：X172　　文献标识码：A　　文章编号：1009-9212（2023）03-0041-06

Screening, Identification and Degradation Characteristics of a Pyrimidine-degrading Bacterium

ZHAO Zhen-hua, SHAO Ru-ying, GAO Feng, LI Meng-lin (Jiangsu Lason Chemical Environmental Protection Co., Ltd., Yixing 214200, China)

Abstract：A gradient batch domestic method was used to isolate a high-efficiency pyrimidine-degrading bacterium LBQ-M5 from the activated sludge of the aerobic tank in the biochemical treatment of pesticide wastewater. The bacterium was able to grow using pyrimidine as the only carbon and nitrogen source. The phylogenetic analysis of the 16S rDNA sequence showed that the phylogenetic relationship between the strain LBQ-M5 and the Oceanobacillus iheyensis strain was the closest, with a sequence similarity of 99.87%. The results showed that the strain LBQ-M5 could efficiently degrade pyrimidine under the conditions of temperature 25~40 ℃, pH=6.5~9.0, shaker speed 150~250 r/min, and under the optimum degradation conditions (temperature 30 ℃, pH=7.0, shaker speed 150 r/min), when the initial pyrimidine concentration was 500 mg/L, the pyrimidine degradation rate of the strain could reach 100% within 24 h; 1 000 mg/L pyrimidine degradation rate was 100% in 36 h; the degradation rate of 1 500 mg/L pyrimidine was 99.8% in 48 h; the degradation rate of 2 000 mg/L pyrimidine was 98.9% in 72 h. The salt tolerance experiment of the strain showed that the strain LBQ-M5 could efficiently degrade pyrimidine in the range of 0.5%~2.5% salinity (NaCl mass fraction), and the degradation rate of 500 mg/L pyrimidine in 24 h was 100%; when the salinity was 3.5%, the pyrimidine degradation rate was still 91.2%, indicating that the strain LBQ-M5 was a moderately salt-tolerant bacteria.

Key words：pyrimidine; Oceanobacillus sp.; biodegradable

作者简介：赵振华（1994—），男，四川达州人，研究方向：生物工程（E-mail:zhaozhenhua@china-lason.com）。

收稿日期：2023-05-04