苯酚降解细菌的分离与选育研究

Study on Isolation and Screening of Phenol-degrading Bacteria

采用焦化废水处理厂的活性污泥为菌源,以苯酚为唯一碳源进行苯酚降解细菌的分离与选育研究,结果从焦化废水处理厂的活性污泥中驯化、筛选出了5株具有高效降解苯酚能力的菌株;通过生理生化反应及外观特征观察,对5株苯酚降解菌株的初步鉴定结果为:phen-8为产碱杆菌属(Alcaligenes),phen-9为微球菌属(Micrococcus),phen-24为芽孢杆菌属(Bacillus),phen-78、phen-103为假单胞菌属(Pseudomonas);经物化诱变处理后得到1株生长更快并对苯酚具有更高降解率的诱变菌株(phen-24),该菌株在30℃下,于pH值为7.0、苯酚浓度为400 mg/L的唯一碳源培养基中的生长状况较好,培养9 h后苯酚几乎被完全降解。

The study on isolation and screening of phenol-degrading bacteria was conducted using the activated sludge of a coking wastewater treatment plant as bacteria source and phenol as single carbon source. Five kinds of strains with high degradation abilities of phenol were acclimated and screened out from the activated sludge of the coke wastewater treatment plant. The physiological, biochemical and appearance identifications of the five strains show that phen-8 belongs to Alcaligenes, phen-9 to Micrococcus, phen-24 to Bacillus, phen-78 and phen-103 to Pseudomonas. The five original strains are repeatedly treated with UV and NTG mutagenesis, which screens out phen-24 mutant strain, with the highest phenol-degrading ability. The best growth conditions for the phen-24 mutant strain are temperature of 30 ℃, pH of 7.0, phenol concentration of 400 mg/L. Within 9 hours, phenol is almost completely degraded.