石油污染土中微生物的分离鉴定及降解特性

张娟　方祥位　刘汉龙　肖杨　张楠　曹小方

摘 要：为了为汽油污染土的微生物修复提供优良菌种，以LB培养基为基质，从石油污染土中对汽油降解菌进行了分离鉴定，以降油培养基为基质对分离得到的菌株进行汽油降解率的测定，以培养温度、培养基pH值及培养时间为参数对5种具有优良汽油降解性能的菌株进行单因素试验，基于单因素试验结果进行三因素三水平的正交试验后，以汽油降解率为响应值对试验结果进行响应面分析，筛选出具有优良降解性能的菌株，并确定了菌株降解汽油的最佳条件。结果表明：从石油污染土中分离出了9种具有汽油降解性能的菌株，其中，铜绿假单胞菌、假单胞菌属、苍白杆菌属、博得特氏菌属以及戈登氏菌属具有优良降解性能，这5种菌降解汽油的最优条件为：铜绿假单胞菌、假单胞菌属、苍白杆菌属、博得特氏菌以及戈登氏菌的最佳培养温度均为32 ℃，培养基pH值均为7.0，培养时间均为20 h，降油培养基中的汽油降解率分别为70.12%、76.42%、75.66%、77.50%和73.22%。

关键词：石油污染土;汽油降解率;微生物;正交试验;污染土修复

中图分类号：X53 文献标志码：A 文章编号：2096-6717（2020）01-0144-09

Abstract：In order to provide excellent strains for microbial remediation of gasoline-contaminated soil， the gasoline-degrading bacteria were isolated and identified from petroleum-contaminated soil using LB medium as the substrate， and the gasoline degradation rate was determined by using the oil-reducing medium as the substrate. Single factor test was carried out on five strains with excellent gasoline degradation performance at culture temperature， medium pH and culture time. Based on the single factor test results， three factors and three levels of orthogonal test were carried out to degrade with gasoline. Response surface analysis of test results with gasoline degradation rate response， screening of strains with excellent degradation performance and determining the optimal conditions for the degradation of gasoline by the strain. The results showed that nine strains with gasoline degradation properties were isolated from petroleum contaminated soil. Among which Pseudomonas aeruginosa， Pseudomonas， Pleurobacter， Bordetella and Goldenella had excellent degradation performance. The optimal conditions for determining the degradation of gasoline by these five kinds of bacteria as follows： The optimum culture temperature for Pseudomonas aeruginosa， Pseudomonas， Pleurobacter， Bordetella and Gordonia is 32℃，the pH of the medium is 7.0 and the culture time is 20 h. The degradation rates of gasoline in the oil-reducing medium are 70.12%， 76.42%， 75.66%， 77.50% and 73.22%， respectively.

Keywords：petroleum contaminated soil; gasoline degradation rate; microorganisms; orthogonal test; remediation of contaminated soil

石油是一種重要的能源，对经济和人民的生活水平都有很大的推动作用，但在石油的开采、加工以及运输过程中会发生石油泄漏等问题，资料表明，中国目前直接进入到环境中的石油约有6×105 t，对土壤以及地下水造成严重污染。而汽油是用量最大的轻质石油产品之一，汽油物质进入……