高效石油降解菌的筛选及降解特性研究

Screening of High-efficient Petroleum Degradation Bacteria and Study on Their Degradation Characteristics

石油污染土壤是一个严重的生态环境问题,甚至会威胁公众健康。石油污染土壤的微生物修复技术因低廉、绿色和无二次污染等备受关注。为了强化石油污染土壤生物修复技术,筛选高效的石油降解菌种,该研究从大庆石油污染土壤中筛选出1株高效石油降解菌,经16S rRNA鉴定分析为琼式不动杆菌,该菌株对1%的石油的降解率高达60.2%。利用扫描电镜分析该菌株在石油污染土壤降解前后的形态变化原因,并通过改变降解环境的盐度、pH以及接种量的单因素实验,探究3种因素对细菌的活性、生长量和降解率的影响。结果表明,该细菌形态呈节杆状,且在降解过程中产生生物表面活性剂并分泌一定的胞外聚合物;在石油浓度为1%的条件下,该菌株对盐度的耐受性在4%以下,适应的p H范围为5~9,投菌量在15~20 mL时,降解效果较好。

Oil pollution of soil is a serious ecological and environmental problem,and even threatens public health.Microbial remediation of oil-contaminated soil has attracted much attention due to its low cost,green and no secondary pollution.In order to strengthen the bioremediation technology of oil-contaminated soil and screen high-efficiency oil-degrading strain,a high efficient oil-degrading strain was screened from oil-contaminated soil in Daqing,which was identified and analyzed by16S rRNA as Acinetobacter junii,and its degradation rate of 1%oil was as high as 60.2%.Scanning electron microscope was used to analyze the morphological changes of the strain before and after the degradation of oil-contaminated soil,and the effects of three factors on the activity,biomass and degradation rate of bacteria were explored by changing the salinity,p H and inoculation amount of the degradation environment.The results showed that the strain was rod-shaped,and produced biosurfactant and secreted some extracellular polymers in the degradation process.At 1%oil concentration,the tolerance of this strain to salinity was below 4%,the p H range of adaptation was 5~9,and the degradation effect was better when the dosage of bacteria was 15~20 m L.