ATP生物发光法快速检测食源性致病菌的研究

STUDY ON RAPID DETECTION OF FOOD-BORNE PATHOGEN BY ATP BIOLUMINESCENCE METHOD

由于微生物在特定的生长阶段ATP含量稳定,因此可通过测定食品内微生物ATP总含量进行活菌计数。通过平板计数法与ATP生物发光法,建立了7种常见食源性致病菌菌落浓度与相应发光强度的数学模型,并通过SAS软件分析了菌种间ATP含量的差异,进而评价生物发光法进行菌落计数的可靠性。结果显示:7种食源性致病菌数学模型的线性相关系数中有6种均大于0.93,P<0.05;肠致病性大肠埃希氏菌为0.861 2,P<0.05,相关性均显著。当发光值相同时不同菌种所含菌落总数无显著差异,当菌落浓度相同时各菌种所含ATP总含量无显著差异。综合试验结果得出:ATP生物发光法可定量检测7种食源性致病菌的数量,而且不同种类致病菌对计数结果影响不显著,这为ATP生物发光在食品质量安全的应用提供了理论支撑。

The number of viable bacteria in food could be measured by total ATP amount in microbial cells due to the stable ATP content in specific stages of microbial growth. Mathematical models between concentration of seven types of foodborne pathogenic bacteria colony and their relative luminous intensity were established using plate count method and ATP bioluminescence method;variation of ATP content between seven different strains was analyzes by SAS software and the reliability of colony counting by bioluminescence method was evaluated. The results showed that a linear relationship between ATP concentration and luminous intensity was observed. Correlation analysis between bioluminous intensity and plate count indicated that liner relationship of mathematical models among the seven types of strain existed;the correlation coefficient values of six types of strains were above 0.93 except 0.8612 for Escherichia coli, P〈0.05 （significant at the 95% level）. There were no significant differences of total bacterial colony number between different strains with same luminous intensity; similarly, no obvious differences of total ATP content were observed when number of bacterial colony were equal. We could draw conclusions from the results that number of the seven kinds of foodborne pathogenic bacteria could be quantitatively detected by ATP bioluminescence method. In addition, effects of different kinds of pathogenic bacteria on the results of bacterial colony counting number showed no significant differences, which provided theoretical support for the application of ATP bioluminescence method in the analysis of food quality and safety.