PCR检测乳品中大肠杆菌的研究

Detection of E.coli in Dairy Products by Polymerase Chain Reaction Method

用大肠杆菌人工污染乳样品直接或8h增菌后提取DNA模板,以大肠杆菌丙氨酸消旋酶基因alr保守区设计引物,经过PCR扩增凝胶电泳检测,不增菌条件下全脂乳和脱脂乳的检出限为104CFU/ml,增菌后检出限为1CFU/ml。与国标鉴别培养法比较,PCR法时间缩短、灵敏度和准确度提高,该法更适宜乳品生产经营的快速实时检测。

In the polymerase chain reaction(PCR) detection procedure of E.coli in milk sample,DNA template was extracted from the milk sample which was contaminated by E.coli artificially after 8-h enrichment or directly,and primer was designed from the conservative region of E.coli alanine racemase gene(alr).After PCR amplification,agarose gel electrophoresis was conducted.The results showed that the detection limits of E.coli in both whole and skim milk samples with and without 8-h enrichment of E.coli are 1 CFU/ml ...