Yeast cell wall products effect on attachment of harmful foodborne strains of Salmonella to intestinal porcine enterocyte cell line (IPEC-J2)

Yeast cell wall (YCW) prebiotics from Saccharomyces cerevisiae , can be added to the diet of animals as an effective decoy molecule for Gram negative bacteria, helping to prevent colonisation of the gut by disease-causing organisms. However, the form and processing of YCW can affect its efficacy in preventing attachment of pathogens to the gut wall and, hence, colonisation. Several commercial yeast cell wall products, A, B and C, including a mannan rich fraction (MRF) product, were assessed for their ability to interfere with the attachment of Salmonella spp. to intestinal IPEC-J2 cells. Attachment of three serovars S. enterica Enteritidis, S. enterica Heidelberg, and S. enterica Typhimurium to IPEC-J2 cells was consistently inhibited with addition of MRF and, to a lesser extent, products B and C, while product A resulted in a greater attachment compared to the control. The reduced attachment of the three Salmonella spp. serovars to IPEC-J2 cells in the presence of MRF coincided with lower gene expression and protein of inflammatory markers interleukin (IL)-1 β , IL-8 and tumour necrosis factor α . However, products B and C had a more limited impact. Inversely IPEC-J2 cells in the presence of product A demonstrated higher inflammatory gene expression likely as a consequence of higher Salmonella attachment rates. This is important regarding gut health and function, as inflammation is implicated in poor performance and health. The use of MRF and, to a lesser extent, products B and C provided a means to limit the proliferation of foodborne strains of Salmonella spp. found in pig intestinal cells.