应用流式细胞技术快速定量检测UHT奶产品中的微生物

Quantitatively Detect Microorganism in UHT Milk Rapidly by Using Flow Cytometry

采用基于单个活细胞的新型荧光标记技术，精确区分UHT奶样品中的活菌细胞与死细胞以及其他大颗粒物质，并应用流式细胞技术（flow cytometry，FCM）对UHT奶产品进行微生物快速定量检测。通过与传统的平板计数检测方法进行比对，结果表明，FCM方法的检测范围为10^1～10^7CFU／mL，远远高于平板计数法。2种方法的计数结果相关性分析表明，在一定菌液浓度范围内，FCM方法的定量结果与平板计数法线性相关良好，且对不同类型菌种都能精确标记定量，是更为快速、准确的检测方法。

In this research we distinguish the live cells, dead cells and other large particles accurately in the UHT milk samples using a new Fluorescence Labeling Technique basing on single live cell, and quickly detect micro- organism quantitatively by using flow cytometry. Comparison with traditional plate counting method shows that the detection range of FCM is 101 - 107 CFU/mL, far above that of plate counting method. Correlation analysis of the results of the two methods shows that within certain concentration range of bacteria solution, the results of FCM and plate counting method are linear, and FCM is a more accurate and rapid detection method for different types of microorganism.