Safety evaluation of two bacterial strains used in Asian probiotic products

Can J Microbiol. 2008 May;54(5):391-400. doi: 10.1139/w08-022.


Probiotics, known for their prophylactic and therapeutic properties, are routinely used by the medical community in various regions of the world. In some Asian countries, these products are controlled as pharmaceutical substances and must adhere to strict regulatory guidelines. However, outside of Europe where the European Food Safety Authority has recently adopted a Qualified Presumption of Safety approach for probiotics used in food and feed, current safety requirements do not necessitate screening for the presence of virulence and other risk factors, which may result in the inadvertent use of probiotic strains harboring harmful genes. A safety evaluation was conducted on Enterococcus faecium R0026 and Bacillus subtilis R0179 used in several commercial probiotic products marketed in Asia. Molecular techniques were used to verify the identity of each strain and antibiotic resistance profiles were determined towards clinically relevant antibiotics. Strains were subsequently screened for the presence of enterotoxins and virulence factors and were subjected to 28 days of repeated high-dose oral toxicity testing in rats. No risk factors or aberrant activities were identified using such a detailed approach. Thus, both microbes were deemed to pose low risk to the consumer and, therefore, safe for use as probiotics.

MeSH terms

  • Animals
  • Anti-Bacterial Agents / pharmacology
  • Asia
  • Bacillus subtilis / drug effects
  • Bacillus subtilis / isolation & purification*
  • Bacillus subtilis / pathogenicity
  • Bacillus subtilis / physiology
  • Bacterial Adhesion
  • Bacterial Proteins / genetics
  • Bacterial Toxins / genetics
  • Consumer Product Safety / standards*
  • DNA, Bacterial / genetics
  • DNA, Ribosomal / genetics
  • Enterococcus faecium / drug effects
  • Enterococcus faecium / isolation & purification*
  • Enterococcus faecium / pathogenicity
  • Enterococcus faecium / physiology
  • Epithelial Cells / microbiology
  • Female
  • Food Microbiology
  • Gram-Positive Bacterial Infections / microbiology
  • HT29 Cells
  • Humans
  • Male
  • Molecular Sequence Data
  • Plasmids / genetics
  • Probiotics / chemistry*
  • Probiotics / metabolism
  • Probiotics / toxicity
  • RNA, Ribosomal, 16S / genetics
  • Rats
  • Rats, Sprague-Dawley
  • Virulence Factors / genetics


  • Anti-Bacterial Agents
  • Bacterial Proteins
  • Bacterial Toxins
  • DNA, Bacterial
  • DNA, Ribosomal
  • RNA, Ribosomal, 16S
  • Virulence Factors

Associated data

  • GENBANK/DQ985157
  • GENBANK/DQ985158
  • GENBANK/DQ985159
  • GENBANK/DQ985160