A multispecies probiotic has shown beneficial effects in irritable bowel syndrome (IBS).
In addition, certain other probiotics have demonstrated advantageous effects, but the mechanisms behind this are poorly understood.
Dr Kajander and colleagues from Helsinki investigated the mode of action of a multispecies probiotic consisting of Lactobacillus rhamnosus.
|Bifidobacterium spp. decreased in the probiotic group|
|Alimentary Pharmacology & Therapeutics|
Lactobacillus rhamnosus Lc705, Propionibacterium freudenreichii ssp. Shermanii JS and Bifidobacterium breve Bb99 were also monitored for its effects on intestinal microbiota and markers of microbial activity.
The team assessed a total of 55 irritable bowel syndrome patients in this placebo-controlled double-blind trial.
Subjects received either multispecies probiotic or placebo supplementation daily during a 6-month period.
The composition of intestinal microbiota was analyzed with real-time polymerase chain reaction.
The research team analyzed short-chain fatty acids with gas chromatography and enzymes with spectrophotometer.
The researchers detected each supplemented probiotic strain in fecal samples.
Intestinal microbiota remained stable during the trial.
However, Bifidobacterium spp. increased in the placebo group and decreased in the probiotic group.
No changes in short-chain fatty acids occurred.
The team detected a decrease in ß-glucuronidase activity was detected in 67% of the subjects in the probiotic group vs 38% in the placebo group.
Dr Kajander's team concluded, "Factors other than the microbial groups and metabolites studied herein seem responsible for the alleviation of irritable bowel syndrome symptoms by the multispecies probiotic."