食品科学 ›› 2013, Vol. 34 ›› Issue (8): 253-258.doi: 10.7506/spkx1002-6630-201308055

• 分析检测 • 上一篇    下一篇

PCR-DGGE结合种特异性PCR技术检测市售酸奶中乳酸菌

王 营,孟祥晨   

  1. 东北农业大学食品学院,乳品科学教育部重点实验室,黑龙江 哈尔滨 150030
  • 收稿日期:2011-12-29 修回日期:2013-03-15 出版日期:2013-04-25 发布日期:2013-05-07
  • 通讯作者: 孟祥晨 E-mail:xchmeng@163.com

Detection of Lactic Acid Bacteria in Commercial Yoghurt by PCR-DGGE Combined with Species-Specific PCR

WANG Ying,MENG Xiang-chen   

  1. Key Laboratory of Dairy Science, Ministry of Education, College of Food Science and Technology, Northeast Agricultural University, Harbin 150030, China
  • Received:2011-12-29 Revised:2013-03-15 Online:2013-04-25 Published:2013-05-07
  • Contact: [中]孟祥晨 [英]MENG Xiang-Chen E-mail:xchmeng@163.com

摘要: 应用多聚酶链式反应结合变性梯度凝胶电泳技术(PCR-DGGE),并结合种特异性PCR技术检测酸奶中的乳酸菌组成。优化DGGE检测相关条件,结果表明最佳DGGE条件为:凝胶变性梯度范围30%~60%,电泳时间300min。利用上述条件能有效区分植物乳杆菌、乳双歧杆菌,但是无法区分保加利亚乳杆菌与嗜酸乳杆菌,嗜热链球菌、鼠李糖乳杆菌与干酪乳杆菌;在此结果基础上,再采用种特异性PCR技术,能够有效区分上述存在共迁移现象的菌株。采用上述技术检测6种市售酸奶中乳酸菌,发现6种产品中均包含保加利亚乳杆菌、嗜热链球菌、植物乳杆菌和嗜酸乳杆菌;3种产品含有干酪乳杆菌;1种产品标识有双歧杆菌,但未检测到。通过选择性培养基分离计数酸奶样品中乳酸菌,两种方法所得的检测结果相同,验证检测上述方法的可靠性。研究表明,PCR-DGGE与种特异性PCR技术结合可有效检测酸奶中乳酸菌组成。

关键词: 变性梯度凝胶电泳, 种特异性PCR扩增, 乳酸菌, 酸奶

Abstract: Polymerase chain reaction denaturing gradient gel electrophoresis (PCR-DGGE) combined with species-specific PCR was used to detect lactic acid bacteria in commercial yoghurts. DGGE conditions were optimized and the results indicated that the optimal conditions of DGGE were 30%–60% denaturant gradient range and 300 min electrophoresis. Lactobacillus plantarum and Bifidobacterium lactis could be distinguished, while Lactobacillus delbrueckii subsp. bulgaricus and Lactobacillus acidophilus, Streptococcus thermophilus, Lactobacillus casei and Lactobacillus rhamnosus could not be distinguished. Furthermore, species-specific PCR was used to distinguish among the strains with the same migration distance in gel. Lactic acid bacteria in six commercial yoghurts were detected by PCR-DGGE combined with species-specific PCR. All yoghurts contained Lactobacillus delbrueckii subsp. bulgaricus, Streptococcus thermophilus, Lactobacillus acidophilus and Lactobacillus plantarum; three kinds of yoghurts contained Lactobacillus casei; Bifidobacterium lactis stated on the label was not detected in one kind of yoghurt. Lactic acid bacteria in yoghurt were isolated and enumeratied by selective medium and the results were confirmed by previously approved technology. Therefore, PCR-DGGE coupled with speciesspecific PCR was an effective method to detect lactic acid bacteria in yoghurt.

Key words: denaturing gradient gel electrophoresis, species-specific PCR amplification, lactic acid bacteria, yoghurt

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