食品科学

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实时荧光环介导等温扩增技术检测牛乳中的蜡样芽孢杆菌

贾雅菁1,付博宇1,王 羽1,马晓燕1,张先舟1,苑 宁2,张 伟1,*   

  1. 1.河北农业大学食品科技学院,河北 保定 071000;2.河北农业大学理工学院,河北 沧州 061100
  • 出版日期:2016-03-25 发布日期:2016-03-18

Detection of Bacillus cereus in Milk by Real-Time Fluorescence Loop-Mediated Isothermal Amplification Method

JIA Yajing1, FU Boyu1, WANG Yu1, MA Xiaoyan1, ZHANG Xianzhou1, YUAN Ning2, ZHANG Wei1,*   

  1. 1. College of Food Science and Technology, Agricultural University of Hebei, Baoding 071000, China;
    2. College of Science and Technology, Agricultural University of Hebei, Cangzhou 061100, China
  • Online:2016-03-25 Published:2016-03-18

摘要:

建立牛乳中蜡样芽孢杆菌便捷可靠的检测方法,根据已公布的蜡样芽孢杆菌hblA基因序列设计内外引物,并向反应体系中加入荧光染料SYBRGreen Ⅰ,利用实时荧光监测仪,建立实时荧光环介导等温扩增技术(real-timefluorescence loop-mediated isothermal amplification,RealAmp)检测蜡样芽孢杆菌的方法,扩增产物经电泳和酶切鉴定。通过21 株致病菌验证RealAmp特异性,并比较了RealAmp与普通环介导等温扩增技术的敏感性,对人工污染的检出限进行了测定。结果表明对21 株致病菌进行特异性实验,4 株蜡样芽胞杆菌呈阳性结果,17 株非蜡样芽胞杆菌均呈阴性结果。RealAmp检测纯菌的灵敏度为8.2 CFU/mL,比普通环介导等温扩增技术的灵敏度高10 倍,人工污染牛乳RealAmp的检出限为8.2 CFU/mL。并且在20 min左右即可判定结果。该方法快速、准确、灵敏度高、操作便捷、可实时监控检测蜡样芽孢杆菌,有望成为快速检测蜡样芽孢杆菌的有效方法。

关键词: 实时荧光环介导等温扩增检测技术, 蜡样芽胞杆菌, 检测, 牛乳

Abstract:

This study aimed to establish a real-time fluorescence loop-mediated isothermal amplification assay to detect
Bacillus cereus. Based on the published Bacillus cereus hblA gene sequence, primers were designed, and the intercalating
dye SYBR-Green I was added to the reaction system, which allowed the reaction products to be measured by ESE-Quant
Tube Scanner. The products were identified by restriction digestion followed by electrophoresis. The performance of the
assay was evaluated with respect to specificity and sensitivity in comparison with the ordinary LAMP, and the limit of
detection (LOD) for artificially contaminated milk was tested. Among 21 strains tested, four Bacillus cereus strains were
identified, the other 17 strains were negative. The sensitivity for Bacillus cereus was 8.2 CFU/mL in pure cultures, which
was 10 times more sensitive than the ordinary LAMP. The LOD for artificially contaminated milk was 8.2 CFU/mL. The
result could be obtained in 20 minutes. This method has high specificity and sensitivity and is less time-consuming, requiring
only simple equipment and allowing real-time monitoring. It is expected to be applied as an effective method for rapid
detection of B. cereus.

Key words: real-time fluorescence loop-mediated isothermal amplification (RealAmp), Bacillus cereus, detection, milk

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