Breast milk oligosaccharides: effects of 2′-fucosyllactose and 6′-sialyllactose on the adhesion of <i>Escherichia coli</i> and <i>Salmonella fyris</i> to Caco-2 cells

Abstract

<b>Background:</b> It is well known that human milk oligosaccharides play an important role as prebiotics, anti-inflammatory, and anti-infective agents. In the last few years, several studies have been performed using specific oligosaccharides, such as 2'-fucosyllactose and 6'-sialylactose, to evaluate their biological functions. <b>Objectives:</b> The aim of the present study is to evaluate the anti-adhesive effect of the above oligosaccharides on <i>Escherichia coli</i> and <i>Salmonella fyris</i>. <b>Methods:</b> Adhesion experiments were performed in the presence of 2'-fucosyllactose and 6'-sialyllactose as potential inhibitors of <i>Escherichia coli</i> and <i>Salmonella fyris</i> adhesion to Caco-2 cells. The oligosaccharides were used at different concentrations and the adhesion experiments were performed in triplicate and repeated at least three times. <b>Results:</b> A significant reduction of <i>Escherichia coli</i> adhesion was observed in the presence of 2'-fucosyllactose and 6'-sialyllactose at the human milk concentration. On the contrary, no positive effects were observed in both oligosaccharides on <i>Salmonella firis</i>. <b>Conclusions:</b> Our results suggest that the supplementation in infant formulas of 2'-fucosyllactose and 6'-sialyllactose, actually commercially available and absent in cow milk, could play positive effects in artificially fed infants.