实时荧光PCR法与国标法检测单增李斯特菌比较

Comparison of Real-Time Fluorescent PCR and National Standard Method for Detection of Listeria monocytogenes

单增李斯特菌(Listeria monocytogenes)是食源性致病菌之一,可引起人和动物患病。对食品中单增李斯特菌进行检验,对保障食品安全至关重要。为明确实时荧光PCR法在食源性单增李斯特菌检测中的最低检出限以及在不同食品类型中的检出效率,对实时荧光PCR法检测单增李斯特菌的最低检出浓度进行了摸索与验证,对人工污染单增李斯特菌的豆粉、饼干、生菜、猪肉4种食品,在不同培养时间点取样采用实时荧光PCR法检测,同时与国标法GB 4789.30-2016《食品安全国家标准食品微生物学检验单核细胞增生李斯特氏菌检验》检测进行了比较。结果表明,实时荧光PCR法具有检测速度快、灵敏度高的优点,可在快速检测中应用,但因其死菌可以产生假阳性问题,而国标法检测可以分离得到污染菌株用于后续研究,因此,建议对于实时荧光PCR法检测阳性的样品用国标方法复检确认。

Listeria monocytogenes is a foodborne pathogenic bacteria which can cause human and animal diseases.Monitoring and testing Listeria monocytogenes in food is very important.In order to determine the minimum detection limit of real-time fluorescent PCR in the detection of food borne Listeria monocytogenes and the detection efficiency in different food types,the limit of detection of real-time fluorescent PCR method for Listeria monocytogenes were verified in this paper.Listeria monocytogenes was added in four kinds of foods,namely soybean meal,biscuit,lettuce and pork,and was detected by real-time fluorescent PCR method at differrent time points.Through comparing and analyzing with the national standard method,the real-time fluorescent PCR method has the advantages of fast and high sensitivity,and can be applied in rapid detection.However,considering that the dead bacteria can cause false positive problems,the national standard method can seperate the contaminated bacterial strain for further research,it is recommended to recheck and confirm the positive samples using national standard method after PCR detection.