苯酚高效降解菌的筛选和降解特性研究

Isolation and Degrading Characteristics of a Phenol-degrading Bacterial Strain with High Efficiency

摘要:

从东华理工学院北区原化学系排污口土壤中筛选到一株高效的苯酚降解细菌PS1。该菌为球菌，革兰氏染色阴性，能以苯酚为唯一碳源和能源生长。经16S rRNA基因部分序列分析PS1为Raoultella 属菌株Raoultella sp.strain PS1），其最高苯酚耐受和降解浓度在3500mg/L以上，当苯酚浓度为500mg/L和1000mg/L时，22h和32h可完全降解，在1500mg/L～3000mg/L时，32h～50h可完全降解，2500mg/L 时降解速率最快，达78.1mg/h。通过正交试验得出该菌最适生长条件为25℃、pH6.5、葡萄糖500mg/L；最佳苯酚降解条件为20℃、pH7.0、葡萄糖500mg/L。

Abstract:

A high efficiency phenol-degrading bacterial strain PS1 was isolated from the drainage ditch of chemical laboratory of East China Institute of Technology.PS1 is a coccus,Gram negative and can live on phenol as its sole carbon and energy source.PS1 to identified as a strain of Raoultella sp.by 16S rRNA gene sequence analysis,which can degrade and tolerate more than 3500mg/L phenol.When phenol concentration is 500mg/L and 1000mg/L,PS1 can completely degrade it in 22 h and 32h,respectively.And while it is between 1500mg/L～3000mg/L,all phenol can be degraded by PS1 in 32h～50h.When phenol concentration is 2500mg/L,the phenol-degrading rate is the biggest and can reach to 78.1mg/h.The optimum growth and phenol-degrading conditions were obtained by orthogonal experiment,which are 25℃,pH6.5,glucose concentration 500mg/L and 20℃,pH7.0,glucose concentration 500mg/L,respectively.