Probiotics have been shown to improve immunity in animals and humans but the team from Germany's Federal Research Centre for Nutrition notes that the effects of prebiotics on systemic and intestinal immunity have not been investigated.
There is even less reasearch on synbiotic ingredients but their findings show that combining prebiotics and probiotics could open up new areas of health benefit.
The researchers tested the effects of three different supplements - probiotic bacteria Lactobacillus rhamnosus GG and Bifidobacterium lactis Bb12, a prebiotic supplement of inulin enriched with oligofructose and a combination of both of these - added to a high fat diet fed to rats.
Writing in this month's Journal of Nutrition (134:153-156), they report that the synbiotic supplement increased secretory immunoglobulin A (sIgA) production in the ileum compared the with control high fat diet alone. It also decreased the oxidative burst activity of blood neutrophils compared with rats fed probiotics only.
The prebiotic supplement enhanced the production of interleukin-10 in PP as well as the production of sIgA in the cecum compared with controls. The probiotic supplement modestly affected immune functions, whereas systemic immunomodulatory effects were observed in rats fed synbiotics.
Many market analysts have forecast increasing sales of synbiotic products but further research will be needed before consumer awareness can be tapped. Further marketing is still needed before probiotic sales reach their potential, according to a recent Frost & Sullivan report.