Fructooligosaccharides decreased the ability of probiotic Escherichia coli Nissle 1917 to adhere to co-cultures of human intestinal cell lines

In the present study, we investigated effects of prebiotic fructooligosaccharides (FOS) on the ability of Escherichia coli Nissle 1917 (EcN), a probiotic bacterial strain, to adhere to co-cultures of human intestinal cells (Caco-2 and HT29-MTX). For the bacterial adhesion assay, the co-cultures were seeded together at a ratio of 3:1 and then incubated EcN in the presence of various prebiotics including FOS. To eliminate possible bias, both manual and automated cell counting methods were utilized. In results, FOS significantly suppressed the adhesion abilities of probiotic EcN to the co-cultures. Taken altogether, we carefully suggest that an unbalanced supplementation of prebiotics may adversely impact on gut microflora; hence, further investigations are warranted in regards to such unexpected adverse effects and responsible mechanisms on colonization of probiotics in the gastrointestinal tract utilizing in vivo models.