Evaluation of Bacillus subtilis strains as probiotics and their potential as a food ingredient

Benef Microbes. 2012 Jun 1;3(2):127-35. doi: 10.3920/BM2012.0002.


Spores of Bacillus subtilis including one strain used commercially were evaluated for their potential value as a probiotic and as potential food additives. Two isolates of B. subtilis examined here were HU58, a human isolate and PXN21, a strain used in an existing commercial product. Compared to a domesticated laboratory strain of B. subtilis both isolates carried traits that could prove advantageous in the human gastro-intestinal tract. This included full resistance to gastric fluids, rapid sporulation and the formation of robust biofilms. We also showed that PXN21 spores when administered weekly to mice conferred non-specific cellular immune responses, indicative signs of the stimulation of innate immunity. Spores mixed in wholemeal biscuits were found to survive baking at 235 °C for 8 minutes with only a 1-log reduction in viability. That spores can survive the baking process offers the possibility of using spores as probiotic supplements in a range of novel food products.

Publication types

  • Comparative Study

MeSH terms

  • Administration, Oral
  • Animals
  • Bacillus subtilis / immunology*
  • Bacillus subtilis / physiology*
  • Diet / methods
  • Dietary Supplements*
  • Female
  • Immunologic Factors / administration & dosage*
  • Mice
  • Mice, Inbred BALB C
  • Probiotics / administration & dosage*
  • Spores, Bacterial / immunology
  • Spores, Bacterial / physiology


  • Immunologic Factors