机油高效降解菌的筛选鉴定及降解特性的初步研究

Isolation and Identification of Bacteria Efficiently Involved in Engine Oil Degradation and Their Biodegradable Property

为丰富机油降解微生物菌种库,筛选适应性更强的机油高效降解菌株。以20#机油和真空泵油为唯一碳源,筛选出机油高效降解菌,经细菌形态学、生理生化及16S rRNA序列分析对机油高效降解菌株进行鉴定,采用紫外分光光度法和气相色谱质谱联用(GC-MS)研究菌株降解特性。从初筛的22株机油降解菌中筛选出4株机油高效降解菌株,分别为JZ6、JZ18、JZ41和JZ50,经鉴定4株菌株分别为Massilia sp、Pseudomona sp、Sphingobacterium sp和Shinella zoogloeoides sp,在含机油培养基中30℃培养7 d后,机油降解率分别为42.62%、33.67%、33.36%和40.52%。在温度20-40℃,pH5-9条件下菌株都具有降解机油的能力,4株菌株均能以十二烷、十六烷、十八烷和苯和萘为唯一碳源生长,JZ6和JZ50还能在含芘和菲的培养基中生长。GC-MS分析发现菌株JZ6、JZ18、JZ41和JZ50对总烷烃的降解率分别达到68.66%、52.69%、49.37%和61.40%,对直链烷烃的降解率分别为86.89%、55.98%、58.42%和89.13%,其中菌株JZ6和JZ50对除烷烃的其他芳香烃类物质也具有一定的降解作用。筛选出的4株机油降解菌具有较强机油降解能力,适应性强,可用于机油污染环境的生物修复。

We aimed to isolate and identify highly efficient and highly-adapted engine oil-degrading bacteria for enriching the engine oil-degrading microbial strain library. Efficiently oil-degrading bacteria were obtained using the media individually supplemented with No.20 oil and vacuum pump oil as the sole carbon source,and were identified by morphology,physiological and biochemical properties,and 16S rRNA gene phylogenetics. Degradation characteristics of the strains were analyzed using UV spectrophotometry and gas chromatography mass spectrometry（GC-MS）. The most efficient oil-degrading strains,designed as JZ6,JZ18,JZ41,and JZ50,from 22 oil-degrading strains were classified as Massilia sp,Pseudomona sp,Sphingobacterium sp,and Shinella zoogloeoides sp,respectively. The degradation rate of oil reached 42.62%,33.67%,33.36% and 40.52%,when these strains were cultured in oil-containing media at 30 ℃ for 7 d. The strains were capable of degrading oil under the condition of pH5-9 and 20-40℃. The four strains grew on the media respectively added by dodecane,hexadecane,octadecane,benzene and naphthalene as the sole carbon source,and the strain JZ6 and JZ50 also grew well in the media containing pyrene and phenanthrene. GC-MS analysis showed that the degradation rate of strain JZ6,JZ18,JZ41 and JZ50 to total alkane was 68.66%,52.69%,49.37%,and 61.4%,and that to straight chain was 86.89%,55.98%,58.42%,and 89.13%,respectively. The strain JZ6 and JZ50 also degraded other aromatic hydrocarbon ta varied degree. The four strains of efficient oil-degrading bacteria were obtained,and had strong adaptability,thus these isolates can be used in the biological remediation of oil-polluted environment.