【摘要】 通过液体富集培养,平板培养分离法从焦化废水的污泥中分离出1株可耐受2 000mg/L苯酚的菌株,经16S rDNA序列分析,鉴定为施氏假单胞菌(Pseudomonas stutzeri)。该菌能以苯酚为唯一碳源和能源生长。通过摇瓶试验和高效液相色谱(HPLC)分析法可知,在pH=7.5,温度为30℃的条件下,苯酚质量浓度在50～400mg/L时,该菌细胞生长和对苯酚的降解转换快速同步进行。当苯酚质量浓度在800～900mg/L,菌细胞依次出现快速生长、延缓生长、次快速生长3个生长时期,在前两时期内苯酚降解率低于5%,在次快速生长期内苯酚降解率从低于5%快速增加到100%。气相色谱-质谱联用仪(GC-MS)测定结果表明,该菌可将苯酚转化成4-羟基-2-氧代戊酸、邻苯二酚、对苯二酚、3,4-二羟基苯甲酸和对羟基苯甲酸等中间产物。更多还原

【Abstract】 The aim of this study is to isolate and characterize a strain capable of high-phenol-tolerance so as to determine the kinetics of biodegradation on the intermediates based on phenol degradation.To achieve our research goal,we have adopted the liquid culture enrichment and plate-spreading method for isolating the strain from the activated sludge of coking plant sewage with it being identified by 16S rDNA gene-sequencing method as Pseudomonas stutzeri and nominated as Pseudomonas stutzeri N2.And,next,the strain cultured under the temperature of 37 ℃ was allowed to grow on a plate with 2 000 mg/L of phenol till it turns to be a sole carbon energy source.And,later,the cultivating process was conducted with the fast cell-growth and phenol transformation,with no need to retard the growth period,so as to ameliorate the phenol-removing efficiency to 100% in 30 hours.Such an efficiency could also be made possible by shaking the testing flask at 150 r/min in the aerobic condition and high-efficient liquid chromatography(HPLC) with pH=7.5,under 30 ℃,at the initial concentrations of phenol from 50 mg/L to 400 mg/L.However,when the initial concentrations of phenol were within 800-900 mg/L,three cell growth periods would be needed,that is,the fast growth,retarding growth,and inferior fast growth,correspondingly.The transformation rate of phenol proves to be low(only less than 5%) in the fast growth period and retarding growth period,whereas the transformation rate within the inferior fast growth periods would likely to increase from 5% to 100% quickly.The removal efficiency of phenol by the strain would also be made to reach 100% in the liquid medium with 800 mg/L phenol in 50 hours,and the phenol degradation rate would be made to reach 100% in the liquid medium with 900 mg/L phenol for 90 hours.And,finally,we have also investigated the metabolites with trimethylsilylation of the sample by N,O-Bis(trimethylsilyl) acetamide,with the gas chromatography/mass spectrometry(GC/MS) analysis,and five intermediates of phenol degradation detected by Pseudomonas stutzeri N2.更多还原