Inulin: Fermentation and microbial ecology in the intestinal tract

It is well documented that the indigenous microflora, particularly in the c olon, plays an important role as a natural resistance factor against pathog enic microorganisms. The number of beneficial bacteria can be increased by specific non-digestible carbohydrates known as prebiotics. One category of prebiotic is inulin, a non-starch polysaccharide consisting of chains of fr uctose units coupled by beta(2,1)bonds, frequently terminated by a single g lucose moiety naturally occurring as a storage carbohydrate in many plant s pecies. From the results of various in vitro and in vivo studies in animals and humans, inulin can be considered a prebiotic with a bifidogenic factor : it selectively stimulates the in vivo growth of bacteria such as Bifidoba cterium, Lactobacillus, and Bacteroides at the expense of potential pathoge nic microorganisms. Regarding safety, the tolerance level for inulin is far above the bifidogenic level.