1Department of Life Science, Chung-Ang University, Seoul, Korea
Recently the use of antibiotics for animal as growth promoters was prohibited, therefore, a wide variety of probiotics for animal feeding have been developed and marketed. However, labeling on commercial probiotic products for animal feeding often do not represent the true microbiological content. Bacterial communities were investigated in twenty-four commercial probiotics from sixteen brands using barcoded pyrosequencing approach. Pyrosequencing data were processed and classified using RDPipeline (http://pyro.cme.msu.edu) and potential pathogenic bacteria were found by Blastn. Microorganisms labeled on the products were mainly constituted by Lactobacillus, Bacillus, Clostridium (Bacteria) and Saccharomyces (Yeast). The pyrosequencing results indicated that some probiotics were similar between bacteria claimed on the label and classification results; however, discrepancies were also observed in other probiotics. Almost probiotics were showed presence of not declared bacteria. About 2% of the total sequences were closely related to known pathogenic bacteria sequence, such as Pseudomonas aeruginosa, Burkholderia cenocepacia and Escherichia coli. Additionally, detection of virulence gene of the potential pathogens using PCR will perform and discuss.
keywords:probiotics ,pathogenic bacteria ,barcoded pyrosequencing ,virulence gene