Rapid detection and identification Lactobacillus from Sichuan pickle by colony PCR using Lactobacillus-specific primers

Abstract:

Lactobacillus is used as probiotics and there has been much interest. The detection and identification of Lactobacillus from pickle need a rapid method. We designed a pair Lactobacillus-specific primer by analyzing 16S rDNA of 14 Lactobacillus species whose complete genomes had been sequenced. The results of colony PCR showed that an 800 bp band was generated when Lactobacillus and Leuconostoc strains used as template but no band appeared when Staphylococcus epidermidis, Bacillus subtilis, or Lactococcus lactis used as template. Lactobacillus of Sichuan pickle was rapidly detected by a procedure including selection of MRS culture, Gram stain and colony PCR. By sequencing the 800 bp fragment, the detected strain was identified at the species level. 15 Lactobacillus strains were detected from 16 samples of Sichuan pickle. 14 Lactobacillus strains were identified as L. plantarum and a Lactobacillus strain need more identification. The method would detect new Lactobacillus species.