Rapid identification of Streptococcus genus based on surface-enhanced Raman spectroscopy

Rapid identification of foodborne pathogens Streptococcus spp. by surface-enhanced Raman spectroscopies (SERS) was studied. Gold sol was prepared by tri-sodium citrate, and mixed with Streptococcus spp. the SERS signals were collected. First, methods of activation, pre-culturing combinations and the preparation of the colony of Streptococcus agalactia were determined, then the identification of Streptococcus genus from other common pathogenic bacteria of Gram-positive was done by cluster analysis (HCA) and principal component analysis (PCA) , and also the identification could realize between different streptococcal pathogens. The characteristic peaks could be identified at 6h after artificial inoculation Streptococcus agalactiae into commercial full-fat pasteurized milk, which improved effectively the speed of detection. Our results provided the basic information of rapid identification Streptococcus in food, which showed that the SERS technology could be useful in monitoring the foodborne pathogens and in early warning of food safety.