Streptococcus salivarius ameliorates the destructive effect on the epithelial barrier by inhibiting the growth of Prevotella melaninogenica via metabolic acid production.

These results suggest that live S. salivarius or its cell-free supernatant significantly ameliorated the disruption of epithelial tight junctions induced by P. melaninogenica, likely through the inhibition of P. melaninogenica growth mediated by metabolic acid production.