Kawasaki S, Yamashoji S, Asakawa A, Isshiki K, Kawamoto S
National Food Research Institute, Food Hygiene Research Team, Tsukuba-shi, Ibaraki 305-8642, Japan.
J Food Prot. 2004 Dec;67(12):2767-71. doi: 10.4315/0362-028x-67.12.2767.
A menadione-catalyzed luminol chemiluminescence assay was developed for the rapid detection and estimation of viable bacteria in foods. The principle of this assay is based on the extracellular menadione-catalyzed active oxygen spieces (O2- and H2O2) generated by the activity of NAD(P)H:menadione oxidoreductase in viable cells. This luminol chemiluminescence assay requires 10 min for the incubation of cells with menadione and then 2 s for the measurement of chemiluminescence intensity after an injection of luminol solution without the treatment of cell lysis. This method was evaluated using liquid food samples of milk, vegetable juice, green tea, and coffee spiked with Escherichia coli ATCC 25922. The study result revealed that E. coli contamination at 1 to 10 CFU/ml in these foods could be detected after incubation at 37 degrees C for 7 h in an enrichment medium; however, the green tea and coffee samples requires filtration. This method could be a useful tool for the rapid evaluation of microbial food contamination.
开发了一种甲萘醌催化的鲁米诺化学发光分析法，用于快速检测和估算食品中的活菌。该分析方法的原理基于细胞外甲萘醌催化的活性氧（O2-和H2O2），这些活性氧由活细胞中NAD(P)H:甲萘醌氧化还原酶的活性产生。这种鲁米诺化学发光分析法在不进行细胞裂解处理的情况下，将细胞与甲萘醌孵育需要10分钟，然后在注入鲁米诺溶液后2秒测量化学发光强度。使用添加了大肠杆菌ATCC 25922的牛奶、蔬菜汁、绿茶和咖啡等液体食品样品对该方法进行了评估。研究结果表明，在富集培养基中于37℃孵育7小时后，这些食品中1至10 CFU/ml的大肠杆菌污染可以被检测到；然而，绿茶和咖啡样品需要过滤。该方法可能是快速评估食品微生物污染的有用工具。
