第 49 卷第 5 期 Vol. 49 No. 5 2019 年 10 月 Oct 2019

所属栏目：安全与环保 菲高效降解菌1-2D的筛选鉴定及其降解特性

张 晴，白红娟*，孙慧敏，任晓斌，吕 婷 （中北大学 环境与安全工程学院，山西 太原 030051）

摘　要：从山西省太原钢铁集团有限公司排放的废水中筛选出一株高效菲降解菌株1-2D。通过形态特征、生理生化指标和16S rDNA序列同源性分析，菌株1-2D鉴定为适冷假单胞菌（Pseudomonas extremaustralis）。研究结果表明，菌株1-2D生长和降解的适宜条件分别是温度33℃、pH值为7.0~7.5和不外加NaCl，此条件下接种该菌48 h后，菲浓度（50 mg·L-1）降解率达99%。另外，该菌对低温（26~37℃）、偏碱性（pH=6.5~9.0）、低盐（外加NaCl为0~2%）的环境具有良好耐受性。营养物质的添加选择牛肉膏，可较好促进菌株生长和菲降解。通过研究不同菲浓度下菌株1-2D对菲的降解过程，可知其耐受较高菲质量浓度（1 000 mg·L-1）。经菌株1-2D降解动力学分析，该菌降解菲浓度（<500 mg·L-1）的过程与一级降解动力学方程很好拟合，其中25~100 mg·L-1低浓度下该菌快速降解菲，半衰期为6.7~7.0 h，而高浓度菲（1 000 mg·L-1）的该菌降解过程符合零级降解动力学方程，半衰期为39.7 h。

关键词：菲；适冷假单胞菌；降解特性；耐受性；降解动力学

中图分类号：X172　　文献标识码：A　　文章编号：1009-9212（2019）05-0059-07

Screening and Identification of Phenanthrene-degrading Bacteria 1-2D and Its Degradation Characteristics

ZHANG Qing, BAI Hong-juan*, SUN Hui-ming, REN Xiao-bin, LV Ting (School of Environment and Safety Engineering, North University of China, Taiyuan 030051, China)

Abstract：A highly efficient phenanthrene-degrading strain 1-2D was screened from the wastewater discharged from Shanxi Taiyuan Iron and Steel Group Co.,Ltd., Based on morphological characteristics, physiological and biochemical indicators and 16SrDNA sequence homology analysis, strain 1-2D is identified as Pseudomonas extremaustralis. The results show that the optimal conditions for growth and degradation of strain 1-2D are temperature 33℃, pH 7.0~7.5 and no additional NaCl. Under the conditions, the degradation rate of phenanthrene concentration(50 mg·L-1) is 99% after inoculation of the bacteria for 48 h. In addition, the strain has good tolerance to environments with alkaline low temperature(26~37℃), (pH 6.5~9.0), low salt (plus NaCl 0~2%). For the addition of nutrients, the choice of beef extract can promote the growth of the strain and the degradation of phenanthrene. Through the degradation process of phenanthrene by strain 1-2D at different concentrations of phenanthrene, it is known that it is resistant to higher phenanthrene concentration (1 000 mg·L-1). According to the kinetic analysis of strain 1-2D degradation, the process of degradation of medium-low concentration phenanthrene(<500 mg·L-1) by the strain is well fitted with the first-order degradation kinetics equation, in which the strain rapidly degrades phenanthrene at low concentration of phenanthrene (25~100 mg·L-1), and the half-life is 6.7~7.0 h. The high-concentration phenanthrene (1 000 mg·L-1) degradation process accords with the zero-order degradation kinetics equation with ahalf-life of 39.7 h.

Key words：phenanthrene; Pseudomonas extremaustralis; degradation characteristics; tolerance; degradation kinetics

基金项目：山西省回国留学人员科研资助项目（2016-084），山西省研究生教育创新项目资助。

作者简介：张 晴（1995-），女，山西太原人，硕士研究生，研究方向：环境微生物学（E-mail：ttlxzqing@163.com）。

联 系 人：白红娟，教授，研究方向：环境微生物学（E-mail：bhj44871@163.com）。

收稿日期：2019-10-14