摘要
通过选择性富集培养,从活性污泥样品中选育到1株能以扑热息痛为唯一碳源生长的好氧细菌F1.根据菌株F1的形态特征、生理生化特性、16S rRNA基因序列分析及和Biolog测试,初步鉴定为亲铜(Cupriavidus necator)菌属.菌株F1降解扑热息痛最适pH值和温度分别为7.0和30℃;菌株降解扑热息痛的过程遵循Haldane动力学模型,其最大比生长速率μmax为0.097 h-1;其细胞产率系数为0.21 mg/mg.当扑热息痛浓度低于400 mg/L,其降解量与CO2生成量呈线性关系,与扑热息痛完全矿化生成CO2的理论系数值相近,同时该浓度下TOC去除率为92%,表明菌株降解扑热息痛具有较高的矿化率.代谢产物分析表明菌株F1降解扑热息痛可能的主要途径为:菌株首先脱掉扑热息痛乙酰基形成对氨基苯酚,对氨基苯酚进一步脱氨基转化为对苯二酚,继而裂解开环进入TCA循环.
A paracetamol-degrading bacterium F1 was isolated by selective enrichment from activated sludge samples.Based on the morphological characteristics,physiological and biochemical characteristics,16S rRNA sequence analysis and Biolog identification,this strain was tentatively identified as Cupriavidus necator（previously Ralstonia eutropha）.The optimal pH and temperature for F1 biodegradation in shaking flasks were 7.0 and 30℃,respectively.The degrading process of the strain F1 followed the Haldane kinetic model.The maximum specific growth rate and yield coefficient were 0.097 h-1 and 0.21 mg/mg,respectively.At concentrations below 400 mg/mL,the production of CO2 was linearly correlated with paracetamol consumed with a coefficient of 1.5805,close to the theoretical coefficient value.Meanwhile,TOC removal efficiency up to 92% was obtained at the initial concentration of 400 mg/L.The results indicated that strain F1 had a high mineralization extent for paracetamol.The identified metabolites suggested a possible main route for paracetamol metabolism,in which acetyl group was replaced by hydrogen atom to form p-aminophenol as the first degradation product.p-aminophenol was further converted to the ring fission substrate p-phenol,which finally participated in TCA cycles.
出处
《环境科学》
EI
CAS
CSCD
北大核心
2011年第6期1812-1819,共8页
Environmental Science
基金
国家自然科学基金项目(50908210)
浙江省自然科学基金项目(Y507270)
应用化学与生态染整工程浙江省高校重中之重学科开放基金项目(YR2010005)
