一株油脂降解菌的性能研究

Research on the Property of an Oil-degrading Bacteria

为寻找高效的油脂降解菌,从餐厅油烟排出口附近筛选出一株油脂降解菌QZX-A,并采用形态学、生理生化鉴定、基因测序等方法对其进行分类鉴定;采用比浊法和称重法对该菌株的生长性能进行研究;采用排油圈法及蒽酮硫酸法研究了QZX-A菌株生产鼠李糖脂的性能。结果:形态学指标、生理生化指标均显示QZX-A菌株具备铜绿假单孢杆菌的特征,基因测序结果表明QZX-A菌株基因序列与铜绿假单孢杆菌序列的相似度达98%;QZX-A菌株在牛肉膏蛋白胨培养基和发酵培养基中具有相似的生长曲线,但前者的生长速率大于后者;QZX-A菌株代谢产物属于糖脂类化合物,其排油圈可达11 cm,产量为567.75 mg/L。QZX-A菌株遗传性状稳定。

In order to select a high-efficient oil-degrading bacteria, here an oil-degrading bacteria was selected from the lampblack exit of the restaurant, which was named QZX-A. Then, it was identified using the methods such as morphological, physiological and biochemical identification and 16S rRNA. At the same time, its growth performance was anaylzed by the turbidimetric and weighing methods. Furthmore,its ability to produce rhamnolipid was discussed by the method oil-spreading and anthrone-sulfuric acid. Results： On the basis of morphological, physiological and biochemical evidence, strain QZX-A had the characteristics of Pseudomonas aeruginosa bacteria. Phylogenetic analysis based on 16S rRNA gene sequences revealed that QZX-A belonged to a phyletic sub-lineage within the family Pseudomonas, with I〉98% 16S rRNA gene sequence similarity to the described species. In addition, strain QZX- A had a similar growth curve in beef extract peptone and fermentation medium, but the growth rate of the former was bigger than the latter. The result of TLC showed that the metabolic products of strain QZX-A belonged to glycolipid compounds. The oil-spreading round was up to 11 cm, and its productivity was 567.75 mg/L. In sum, since strain QZX- A was genetically stable, it had some value of development in the degradation of oil and in the production of rhamnolipid.