Influence of a synbiotic mixture consisting of Lactobacillus acidophilus 74-2 and a fructooligosaccharide preparation on the microbial ecology sustained in a simulation of the human intestinal microbial ecosystem (SHIME reactor)

Lactobacillus acidophilus 74-2, which is used in probiotic products, was ad ministered, with fructooligosaccharide in a milk-based product, to the seco nd vessel (duodenum/jejunum) of the SHIME reactor, an in vitro simulation o f the human intestinal microbial ecology. The main focus of this study was to monitor the changes of the population density of selected bacterial spec ies in the intestine and the changes of metabolic activities during the sup plementation of L. acidophilus and fructooligosaccharide in the SHIME react or. Interestingly, the addition of L. acidophilus 74-2 with fructooligosacc haride gave rise to an increase of bifidobacteria. Moreover, major positive changes occurred in the production of volatile fatty acids: a strong upwar d trend was observed especially in the case of butyric acid and propionic a cid. Furthermore a noticeable increase of beta-galactosidase activity was m onitored, while the activity of beta-glucuronidase, generally considered un desirable, declined.