邻二甲苯高效降解菌的分离及其降解特性

以邻二甲苯作为唯一碳源,从长期受焦化废水污染的土壤中分离得到一株能降解邻二甲苯的高效菌株LJ5,经生理生化和16S rDNA鉴定,该菌株属于假单胞菌属(Pseudomonas sp.)。菌株LJ5适宜的降解条件为:培养温度35℃,pH=7.0～8.0,摇床转速150r/min。菌株LJ5在邻二甲苯浓度高达2500mg/L时,对其的去除率在30h内可达到73%,它对邻二甲苯的降解过程符合Monod动力学方程,当邻二甲苯浓度远远大于64.32mg/L时,LJ5降解底物速率最高,达到43.29mg/(L·h)。菌株LJ5能在实际焦化废水中很好的生长,菌液投加48h后可使COD降解率达到34.74%。

Separation and biodegradation characteristics of a o-xylene degrading strain

With o-xylene as the sole carbon source,a strain (LJ5) was separated from the soil which was contaminated in the long-term by coking waste water. This strain was identified as Pseudomonas sp. based on its morphology,and 16S rDNA gene sequence. The optimum initial temperature,pH,and shaking speed for B1 utilizing pyridine are 35℃,pH=7.0—8.0 and 150 r/min,respectively. The o-xylene degradation rate was 73% when LJ15 was cultured under o-xylene concentration of 2500mg/L,and the degradation kinetics of o-xylene could be described by the Monod model. When o-xylene concentration was 》64.32mg/L,the degradation rate of strain LJ5 reached an maximum of 43.29mg/(L·h). Strain LJ5 could grow well in the coking waste water which allowed the degradation rate of COD to be 34.74%.