一株柴油高级烃降解菌的筛选与鉴定

Isolation and identification of a diesel alkanes degrading bacterium

从加油站附近土壤取样,以不同的柴油高级烃为碳源、菌体生物量(OD600)为指示,分离筛选柴油高级烃降解菌株,同时应用高效液相色谱(HPLC)、气相色谱-质谱(GC-MS)分析其降解率以及降解产物。结果筛选到一株对二苯并噻吩、芳香烃类都具有一定降解效果的菌株B5,它对二苯并噻吩的降解率为63.0%,芳香烃类降解率为83.4%。该菌株能将直链烷烃(如正十二烷)的末端羧基化形成羧酸类物质,在实际应用中具有提高油品润滑性质的潜力。经16S rRNA基因鉴定,该菌株为一株红平红球菌(Rhodococcus erythropolis),并被命名为R.erythropolis B5。

A bacterium with the ability of diesel alkanesdegradation was isolated from the soil sample near gas station with different diesel alkanes as carbon sources and biomass density（OD600） as indicator.High performance liquid chromatography（HPLC） and gas chromatography-mass spectrometry（GC-MS） were used to analyzed the degradation efficiency and the degradation products of the bacterium. The isolated bacterial strain B5 could metabolize and degrade dibenzothiophene and aromatic hydrocarbons,with the degradation efficiency of 63. 0% and 83. 4% respectively. In addition,the alkyl group at the end of straight-chain alkanes can be transformed into carboxyl group by the strain through carboxylation,which potentially helps to enhance the lubricating performance of diesel. Finally,this strain was identified to be Rhodococcus erythropolis by sequencing the 16 S rRNA gene and was named as R. erythropolis B5.