B. longum/Inulin Blend has Positive Effects on Gut Microbiota and Immune Response

The microbiota of the elderly differs from that of younger adults. It is characterized by a decrease in the diversity of bacterial species, an increase in number of pathogenic and putrefactive bacteria and a decrease in beneficial bacteria such as Bifidobacteria.

A double-blind, crossover, placebo-controlled study was conducted to determine the effects of a symbiotic, on the gut microbiota, gut health and immune response in 43 healthy elderly volunteers. The duration of the study was 12 weeks. The subjects consumed B. longum 200 bill/cap and 6 g of inulin, or placebo for 4 weeks, followed by a 4 week washout, before switching to the opposite feeding regime. The symbiotic/placebo was taken twice daily right after breakfast and dinner.

In the volunteers receiving the symbiotic, a significant increase, in the phylum Actinobacteria, which includes Bifidobacteria, was observed. Species belonging to the phylum Firmicutes also increased significantly, while Proteobacteria which includes Enterobacteriaceae, decreased. The phylum Firmicutes contain members that ferment carbohydrates and produce butyrate in the gut. It is the principal energy source for intestinal cells. Butyrate also supports the immune system, provides anti-inflammatory effects and helps maintain mucosal barrier integrity.

In conclusion, this short-term study showed that the intake of a symbiotic(probiotic/prebiotic) results in an increase in Bifidobacteria and an increase in short chain fatty acids such as butyrate and acetate.  Furthermore, Proteobacteria, which are associated with inflammation, were reduced in number and certain pro-inflammatory immune components were reduced.

This study provides evidence that synbiotics have the potential to maintain a health gut microbiota and reduce pro-inflammatory responses associated with aging.


Synbioticconsumptionchangesthemetabolismand compositionofthegutmicrobiotainolderpeopleandmodiïammatoryprocesses:arandomised,double-blind,placebo-controlledcrossoverstudy

S.Macfarlane*,S.Cleary*,B.Bahrami*,N.Reynolds† &G.T.Macfarlane*

Alimentary Pharmacology and Therapeutics  24 July, 2013