Li Jun, Cheung Win Den, Opdyke Jason, Harvey John, Chong Songchun, Moon Cheol Gon
Samsung Techwin Co., Ltd, Biotechnology Division, 6636 Virginia Manor Rd, Beltsville, MD 20705, USA.
J AOAC Int. 2012 Nov-Dec;95(6):1656-68. doi: 10.5740/jaoacint.12-116.
Salmonella, one of the most common causes of foodborne illness, is a significant public health concern worldwide. There is a need in the food industry for methods that are simple, rapid, and sensitive for the detection of foodborne pathogens. In this study, the Samsung Salmonella Detection Kit, a real-time PCR assay for the detection of Salmonella, was evaluated according to the current AOAC guidelines. The validation consisted of lot-to-lot consistency, stability, robustness, and inclusivity/exclusivity studies, as well as a method comparison of 10 different food matrixes. In the validation, the Samsung Salmonella Detection Kit was used in conjunction with the Applied Biosystems StepOnePlus PCR system and the Samsung Food Testing Software for the detection of Salmonella species. The performance of the assays was compared to the U.S. Department of Agriculture/Food Safety and Inspection Service-Microbiology Laboratory Guidebook (USDA/FSIS-MLG) 4.05: Isolation and Identification of Salmonella from Meat, Poultry, Pasteurized Egg, and Catfish and the and U.S. Food and Drug Administration/Bacteriological Analytical Manual (FDA/BAM) Chapter 5 Salmonella reference methods. The validation was conducted using an unpaired study design for detection of Salmonella spp. in raw ground beef, raw pork, raw ground pork, raw chicken wings, raw salmon, alfalfa sprouts, pasteurized orange juice, peanut butter, pasteurized whole milk, and shell eggs. The Samsung Salmonella Detection Kit demonstrated lot-to-lot consistency among three independent lots as well as ruggedness with minor modifications to changes in enrichment incubation time, enrichment incubation temperature, and DNA sample volume for PCR reaction. Stability was observed for 13 months at -20 degrees C and 3 months at 5 degrees C. For the inclusivity/exclusivity study, the Samsung Salmonella Detection Kit correctly identified 147 Salmonella species isolates out of 147 isolates tested from each of three different enrichment broths (a total of 441 isolates detected), and correctly excluded all 31 nontarget strains analyzed. For the method comparison, statistical analysis was conducted according to the Mantel-Haenszel Chi-square formula for unpaired test portions, and there was no significant difference in the number of positive samples detected between the Samsung Salmonella Detection Kit and the USDA/FSIS-MLG and FDA/BAM reference methods for all 10 food matrixes.
沙门氏菌是食源性疾病最常见的病因之一,是全球重大的公共卫生问题。食品行业需要简单、快速且灵敏的食源性病原体检测方法。在本研究中,依据现行的美国官方分析化学师协会(AOAC)指南,对用于检测沙门氏菌的实时荧光定量聚合酶链反应(PCR)检测试剂盒——三星沙门氏菌检测试剂盒进行了评估。验证包括批次间一致性、稳定性、耐用性以及包容性/排他性研究,还有对10种不同食品基质的方法比较。在验证过程中,三星沙门氏菌检测试剂盒与应用生物系统公司的StepOnePlus PCR系统以及三星食品检测软件一同用于沙门氏菌属的检测。将这些检测方法的性能与美国农业部/食品安全与检验局 - 微生物学实验室指南(USDA/FSIS - MLG)4.05:从肉类、家禽、巴氏杀菌蛋和鲶鱼中分离和鉴定沙门氏菌以及美国食品药品监督管理局/细菌学分析手册(FDA/BAM)第5章沙门氏菌参考方法进行了比较。验证采用非配对研究设计,用于检测生牛肉末、生猪肉、生猪肉末、生鸡翅、生三文鱼、苜蓿芽、巴氏杀菌橙汁、花生酱、巴氏杀菌全脂牛奶和带壳鸡蛋中的沙门氏菌属。三星沙门氏菌检测试剂盒在三个独立批次间展现出批次间一致性,并且在对增菌培养时间、增菌培养温度和PCR反应的DNA样本体积进行微小改变时具有耐用性。在 - 20℃下观察到13个月的稳定性,在5℃下观察到3个月的稳定性。对于包容性/排他性研究,三星沙门氏菌检测试剂盒从三种不同增菌肉汤中测试的147株分离株中正确鉴定出147株沙门氏菌属分离株(共检测到441株分离株),并正确排除了分析的所有31株非目标菌株。对于方法比较,根据用于非配对测试部分的曼特尔 - 亨塞尔卡方公式进行了统计分析,在所有10种食品基质中,三星沙门氏菌检测试剂盒与USDA/FSIS - MLG和FDA/BAM参考方法检测到的阳性样本数量没有显著差异。