Immunomodulating activity of exopolysaccharide‐producing L euconostoc mesenteroides strain NTM 048 from green peas

Aims The present work was aimed to find novel probiotics to enhance the mucosal barrier function of humans. The effectiveness was evaluated in vitro and in vivo . Methods and Results Stimulation of I g A production in mucosal surfaces is one of the most beneficial traits of lactic acid bacteria ( LAB ) for enhancing the barrier. Therefore, 173 LAB strains were evaluated for the ability to induce I g A production using murine P eyer's patch cells. S train NTM 048 isolated from green peas showed the highest activity and was identified as L euconostoc mesenteroides subsp. mesenteroides . This strain was found to tolerate gastrointestinal digestion and produce large amounts of exopolysaccharides, which possess I g A ‐inducing activity. Dietary supplementation with NTM 048 induced a significant increase in the faecal I g A content and plasma I g A levels of BALB /c A mice. A gene expression analysis of P eyer's patch cells revealed that the transforming growth factor‐ β and activation‐induced cytidine deaminase genes were upregulated by NTM 048 intake. Conclusions Strain NTM 048 stimulates P eyer's patch cells to induce intestinal and systemic immune response, revealing the potential of NTM 048 as a probiotic for enhancing the mucosal barrier function. Significance and Impact of the Study This report demonstrates a food‐applicable L euconostoc mesenteroides strain secreting exopolysaccharide that shows high I g A ‐inducing ability.