摘要
目的探讨细菌对柴油降解能力以及细胞表面疏水性及环境影响因子的影响。方法从新疆油田石油污染土壤中分离一株在25℃下高效降解柴油的菌株,考察不同环境因素对细胞表面疏水性的影响,不同疏水性菌体对柴油降解能力的差别,添加不同浓度鼠李糖脂对细胞疏水性及菌株柴油降解性能的影响。结果经鉴定该菌株为Acinetobacter sp.,命名为3064。通过接触角测量法、盐析凝聚法及烃类化合物吸附等方法证明其为一株高疏水性菌株(CSH>80%),通过改变环境因素会影响菌株的疏水性,进而影响其对柴油的降解效率。添加一定浓度的鼠李糖脂表面活性剂能够增加菌株的疏水性,降低菌株表面脂多糖含量,增加其表面负电荷,这有助于菌株对柴油的吸收和降解。结论菌株3064的细胞表面具有很强的疏水性,这有助于菌体细胞对柴油中烃类的摄取。通过改变环境因素及外源添加鼠李糖脂可以加快菌株对柴油的降解。
Objective To study the diesel degradation ability,cell surface hydrophobicity of diesel oil-degrading strain 3064 and the environmental impact factors. Methods The strain was isolated from oil-contaminated soil of Xinjiang Oil Field,and the effects of environmental factors on the hydrophobicity of cell surface,different abilities of hydrophobic bacteria to degrade diesel oil and the effect of different concentrations of rhamnolipid on cell hydrophobicity and diesel degradation performance were investigated. Results The strain was identified as Acinetobacter sp. and named 3064. It was proved to be a highly hydrophobic strain(CSH>80%) by contact angle measurement,salting out coagulation and hydrocarbon adsorption. The environmental factors would affect the hydrophobicity of the strain and its degradation efficiency to diesel. Adding a certain concentration of rhamnolipid surfactant could increase the hydrophobicity,reduce the surface lipopolysaccharide content,and increase the surface negative charge,which would accelerate the strain to absorb and degrade the diesel oil. Conclusion The cell surface of the strain is highly hydrophobic,which contributes to the uptake of hydrocarbons in diesel oil by the cells. By changing environmental factors and exogenous addition of rhamnolipid,the degradation of hydrocarbons can be accelerated,indicating that there is a positive correlation between cell surface hydrophobicity and diesel oil degradation,which provided a theoretical basis for the better application of rhamnolipid in the remediation of diesel oil-contaminated environment.
作者
曹月
郭鹏
朱莹
王倩
曹家畅
邱凯旋
刘沐之
黄磊
刘金彪
CAO Yue;GUO Peng;ZHU Ying;WANG Qian;CAO Jia-chang;QIU Kai-xuan;LIU Mu-zhi;HUANG Lei;LIU Jin-biao(School of Chemistry and Chemical Engineering, Tianjin University of Technology, Tianjin 300384, China)
出处
《环境与健康杂志》
CAS
北大核心
2018年第12期1078-1084,F0003,共8页
Journal of Environment and Health
基金
国家自然科学基金(21777113)
天津市应用基础及前沿技术研究计划资助项目(15JCQNJC08800)
天津市级大学生创新创业训练计划(201710060027,201810060146)
关键词
柴油污染
生物修复
不动杆菌
细胞疏水性
Diesel oil pollution
Bioremediation
Acinetobacter
Cell hydrophobicity
