运用PCR-DGGE技术分析原料乳中腐败细菌的多样性

Application of PCR-DGGE in the Research of Spoilage Bacteria Diversity in Raw Milk

为揭示原料乳中主要的污染细菌种群,从原料乳中提取细菌的总DNA,PCR扩增16SrDNA的V3可变区,再通过DGGE得到指纹图谱。结果表明:原料乳中共检测出12种细菌,说明原料乳中细菌具有较丰富的种群多样性。条带经DNA测序分析表明,猪链球菌(Streptococcus suis)、马肠链球菌(Strepto-coccus equinus)和乳酸链球菌(Lactococcus lactis subsp.)是混合原料乳中的优势污染菌,其次为海豚链球菌(Streptococcus iniae)、解没食子酸链球菌(Streptococcus gallolyticus)和1株非培养的细菌(Unculturedbacterium)。

To reveal the main pollution bacteria population in raw milk, DNA of total bacteria were directly extracted from the raw milk and the PCR amplification of V3 variable region of 16S rDNA were taken in order to get the fingerprint profile by DGGE technology. The results showed that 12 bacteria were detected in raw milk and indicating that there were abundant microbial population in raw milk. The DNA sequences of bands were analyzed and the dominant polluted bacteria in raw milk were found to be Streptococcus suis , Streptococcus equinus and Lactococcus lactis sub sp., Streptococcus iniae , Streptococcus gallolyticus and Uncultured bacterium secondarily.