分光光度法快速检测细菌  

Spectrophotometric Method for Rapid Detection of Bacteria

作　　者：李冬阳[1] 茹柿平[1] 吴坚[1] 应义斌[1] 

机构地区：[1]浙江大学生物系统工程与食品科学学院,杭州310029

出　　处：《分析化学》2010年第4期573-576,共4页Chinese Journal of Analytical Chemistry

基　　金：教育部新世纪人才项目(No.NCET-07-0725);浙江省重点科技项目(No.2008C14077);国家科技专项(No.2009ZX08012-004B)资助

摘　　要：采用分光光度法来检测完整细胞内H2O2酶的活性,以实现细菌的快速检测。由于细菌(本研究以E.coli DH5α为模型)内含有H2O2酶,当往菌液中加入H2O2时,H2O2会在胞内H2O2酶的作用下分解,其分解过程遵循一级动力学反应。通过测量该反应中H2O2在240nm处吸光度的变化,可以得出该一级反应的速率常数,从而获悉菌液的浓度。结果表明:大肠杆菌单位细胞浓度酶活为4.2×10-13L/(s·cell),其速率常数与浓度在5.7×106～5.7×107cfu/mL范围内呈现良好的线性关系,检出限为5.7×106cfu/mL。本方法是一种检测细菌总数的快速方法,测试时间为5～10min。The catalase activity of intact cells was investigated with the UV spectrophotometry to realize the rapid detection for bacteria（E.coli DH5αas a model）.With the addition of hydrogen peroxide to the bacteria solution,the catalase of the bacteria would decompose the hydrogen peroxide,which followed the first-order kinetic.The first-order rate constant that reflected the bacteria concentration was calculated according to the absorbance change of hydrogen peroxide at 240 nm.The results indicated that there was a linear relationship between the rate constant and the E.coli concentration in the range of 5.7×10 6 -5.7×10 7 cfu/mL;the catalase activity of intact E.coli was 4.2×10 -13 L/（s·cell）.This method could be used to detect the bacteria of 5.7×10 6 cfu/mL within 5-10 min.

关 键 词：细菌检测 过氧化氢酶 酶活性 分光光度法 生物传感器 

分 类 号：TS207.4[轻工技术与工程—食品科学]