磁分离结合qPCR快速检测酱卤肉中的沙门氏菌

Magnetic Separation Combined with qPCR for the Rapid Detection of Salmonella in Sauce Meat

摘要:

验证噬菌体磁分离结合实时荧光定量聚合酶链式反应，快速检测方法对食品中沙门氏菌的检测效果。以一株鼠伤寒沙门氏菌的特异性噬菌体T102为分子识别元件，首先将其与羧基化磁珠偶联，制备获得噬菌体磁性颗粒（Phage T102 Magnetic Beads）复合物，利用噬菌体磁性颗粒复合物从食品中特异性分离富集沙门氏菌，然后利用实时荧光定量聚合酶链式反应检测富集后的沙门氏菌。该沙门氏菌快检方法检出限为100 CFU/mL（0.1 CFU/PCR），线性范围为1×102~1×109 CFU/mL，变异系数2.1%，特异性强，检测时间为6 h。实验选取300批食品安全抽检样品与GB 4789.4-2016标准《食品安全国家标准食品微生物学检验沙门氏菌检验》进行比对，均未检出阳性样品，结果一致。该方法可为噬菌体偶联纳米磁珠在食源性致病菌检测领域的应用提供参考依据。

Abstract:

The efficacy of phage magnetic separation combined with fluorescent quantitative polymerase chain reaction (qPCR) for rapid detection of Salmonella in the food matrix was verified. The specific phage of Salmonella typhimurium (ATCC14028), T102, was used as a molecular recognition element and was first coupled with carboxylated magnetic beads to prepare a phage T102-magnetic beads complex. Salmonella was specifically isolated and enriched by the phage T102-magnetic beads complex from the food matrix and then quantified by qPCR. The detection limit of this rapid detection method for Salmonella was 100 colony-forming units CFU/mL (0.1 CFU/PCR). The method had high specificity, with a linear range of 1×102~1×109 CFU/mL and a coefficient of variation of 2.1%. The overall detection procedure takes 6 h. Three hundred batches of food safety samples were tested and compared with the “National Standard for Food Safety, Food Microbiology Inspection, Salmonella Inspection” (GB 4789.4-2016). No positive samples were detected, and the results were consistent with the results of the GB 4789.4-2016 standard method. This method provides a reference for the application of phage-coupled magnetic nanoparticles in the detection of foodborne pathogens.