食品科学 ›› 2019, Vol. 40 ›› Issue (8): 27-32.doi: 10.7506/spkx1002-6630-20180123-301

• 生物工程 • 上一篇    下一篇

乳酸菌饮料中嗜酸乳杆菌的实时荧光定量PCR检测方法

张娜娜,刘 洋,俞 漪,赵 渝,窦同海,徐 琼,段文锋,翁史昱   

  1. 1.上海市质量监督检验技术研究院,国家食品质量监督检验中心(上海),上海 200233;2.上海师范大学生命与环境科学学院,上海 200234;3.复旦大学生命科学学院,上海 200438;4.上海市质量管理科学研究院(上海),上海 200050
  • 出版日期:2019-04-25 发布日期:2019-05-05
  • 基金资助:
    国家自然科学基金青年科学基金项目(31301486);上海市自然科学基金项目(13ZR1439600);国家质量监督检验检疫总局科研项目(2017QK167)

Real-Time Fluorescent Quantitative PCR Method for Detection of Lactobacillus acidophilus in Probiotic Beverages

ZHANG Nana, LIU Yang, YU Yi, ZHAO Yu, DOU Tonghai, XU Qiong, DUAN Wenfeng, WENG Shiyu   

  1. 1. Shanghai Institute of Quality Inspection and Technical Research, National Center of Supervision and Inspection on Food Products Quality (Shanghai), Shanghai 200233, China; 2. College of Life and Environmental Sciences, Shanghai Normal University, Shanghai 200234, China; 3. College of Life Sciences, Fudan University, Shanghai 200438, China; 4. Shanghai Academy of Quality Management (Shanghai), Shanghai 200050, China
  • Online:2019-04-25 Published:2019-05-05

摘要: 目的:为快速准确检测乳酸菌饮料中的嗜酸乳杆菌,建立实时荧光定量聚合酶链式反应(polymerase chain reaction,PCR)检测方法。方法:根据嗜酸乳杆菌NCFM的SPIDR保守区域设计特异性引物与探针,借助建立的实时荧光定量PCR方法进行特异性、灵敏度、重复性以及抗干扰能力验证,并利用模拟样品对方法进行检验,最后对市售的实际样品进行检测。结果:该方法的特异性较好;方法的绝对灵敏度达到3pg,相对灵敏度达103 CFU/mL;重复性检测表明相对标准偏差在2.6%以下。同时进行杂菌干扰实验,在纯基因组水平和培养物水平混合大肠杆菌,扩增均无明显影响,表明建立的方法抗干扰能力较好。利用建立的实时荧光定量PCR方法对模拟样品进行检测并建立标准曲线,得出R2为0.987,线性较好,可进行实际样品的检测。对市售的11 份样品进行检测,其中6 份含有嗜酸乳杆菌菌株,5份不含嗜酸乳杆菌菌株,标记嗜酸乳杆菌的样品全部检测出嗜酸乳杆菌且含量在5.83×102~3.68×104 CFU/mL之间。结论:建立的实时荧光定量PCR方法可快速、准确地检测出乳酸菌饮料中嗜酸乳杆菌。

关键词: 实时荧光定量PCR, 嗜酸乳杆菌, 定量, 检测

Abstract: Objective: To establish a real-time fluorescent quantitative PCR assay for the rapid and accurate detection of Lactobacillus acidophilus in probiotic beverages. Methods: Specific primers and probes were designed based on the conserved SPIDR region of L. acidophilus NCFM. The established method was assessed with respect to specificity, sensitivity and reproducibility, and it was applied to model and commercial samples. Results: The method had good specificity. The absolute sensitivity was 3 pg and the relative sensitivity was 103 CFU/mL. The repeatability expressed as relative standard deviation (RSD) was below 2.6%. At the same time, the amplification was not affected by the coexistence of pure genome or culture of Escherichia coli, indicating that the method has good anti-interference ability. This method showed good linearity (R2 = 0.987) and it was feasible to detect actual samples. Of 11 commercial samples, 6 contained L. acidophilus strains while the rest did not. L. acidophilus was detected in all samples labeled with L. acidophilus in the range of 5.83 × 102 to 3.68 × 104 CFU/mL. Conclusion: The real-time fluorescence quantitative PCR method can quickly and accurately detect L. acidophilus in probiotic beverages.

Key words: real-time fluorescence quantitative PCR, Lactobacillus acidophilus, quantitative, detection

中图分类号: