Abstract：
Uropathogenic Escherichia coli (UPEC) is known to cause 65-75% of human urinary tract infection (UTI) cases. Poultry meat is a reservoir of UPEC, which is suspected to cause foodborne UTIs. In the present study, we aimed to determine the growth potential of UPEC in ready-to-eat chicken breasts prepared by sous-vide processing. Four reference strains isolated from the urine of UTI patients (Bioresource Collection and Research Center [BCRC] 10,675, 15,480, 15,483, and 17,383) were tested by polymerase chain reaction assay for related genes to identify their phylogenetic type and UPEC specificity. A cocktail of these UPEC strains was inoculated into sous-vide cooked chicken breast at 103-4 colony-forming unit (CFU)/g and stored at 4°C, 10°C, 15°C, 20°C, 30°C, and 40°C. Changes in the populations of UPEC during storage were analyzed by a one-step kinetic analysis method using the U.S. Department of Agriculture [USDA] Integrated Pathogen Modeling Program-Global Fit [IPMP-Global Fit]. The results showed that the combination of the no lag phase primary model and the Huang square-root secondary model fitted well with the growth curves to obtain the appropriate kinetic parameters. This combination for predicting UPEC growth kinetics was further validated using it to study additional growth curves at 25°C and 37°C, which showed that the root mean square error, bias factor, and accuracy factor were 0.49-0.59 (log CFU/g), 0.941-0.984, and 1.056-1.063, respectively. In conclusion, the models developed in this study are acceptable and can be used to predict the growth of UPEC in sous-vide chicken breast.
摘要：
已知尿路致病性大肠杆菌(UPEC)引起65-75%的人尿路感染(UTI)病例。禽肉是UPEC的蓄水池，怀疑会导致食源性尿路感染。在本研究中,我们旨在确定通过sous-vide加工制备的即食鸡胸肉中UPEC的生长潜力。从UTI患者的尿液中分离出的四个参考菌株（生物资源收集和研究中心[BCRC]10,675、15,480、15,483和17,383）通过聚合酶链反应测定法检测相关基因，以鉴定其系统发育类型和UPEC特异性。将这些UPEC菌株的混合物以103-4菌落形成单位（CFU）/g接种到sous-vide煮熟的鸡胸肉中，并在4°C下储存。10°C,15°C,20°C,30°C,和40°C。使用美国农业部[USDA]综合病原体建模计划-全球拟合[IPMP-全球拟合]，通过一步动力学分析方法分析了储存过程中UPEC种群的变化。结果表明,无滞后期初生模型和黄平方根次生模型的组合与生长曲线拟合良好,可获得合适的动力学参数。这种预测UPEC生长动力学的组合被进一步验证，使用它来研究25°C和37°C下的其他生长曲线。这表明均方根误差，偏置因子，精度因子为0.49-0.59(logCFU/g)，分别为0.941-0.984和1.056-1.063。总之,本研究中开发的模型是可以接受的，可用于预测sous-vide鸡胸肉中UPEC的生长。
