Sugar Coating Helps Probiotics Survive

FERMOY, IrelandThe health benefits of probiotics are many, but just how the bacteria survive the harrowing trek through the digestive system is still somewhat of a mystery. Scientists from the Alimentary Pharmabiotic Centre, University College Cork, Ireland, have uncovered one key to how probiotics survive long enough to provide their many physiological benefits, including  boosting the immune system and improving gut health.

The researchers found that the outer polysaccharide coating surrounding the probiotic Bifidobacterium breve UCC2003 plays a key role in its survival in the gut, its evasion of the immune system and is also involved in reducing infection levels of a gut pathogen.

 In this study we have shown that the outer EPS (exocellular polysaccharide) coating of Bifidobacterium breve UCC2003 protects the bacteria from acid and bile in the gut and shields the bacteria from the host immune response. Mutants in which the EPS genes have been deleted were found to evoke stronger immune responses. The EPS coating was also shown to prevent colonisation by a gut pathogen Citrobacter rodentium in mice. This surface EPS-dependent pathogen defence represents an exciting new avenue for probiotic research" said Douwe van Sinderen, senior author on the publication. This research has led to an improved understanding of how probiotic bifidobacteria contribute to human and animal health, thereby will help to support their inclusion in functional foods."

The research is published online ahead of print in Proceedings of the National Academy of Sciences (doi 10.1073/pnas.1115621109).