Safety of high doses of Propionibacterium freudenreichii ET-3 culture in healthy adult subjects.

Propionibacterium freudenreichii ET-3 (7025) culture, a cell-free product of whey fermentation by P. freudenreichii ET-3, has been shown to promote the growth of Bifidobacteria through the action of 1,4-dihydroxy-2-naphthoic acid (DHNA). Here we report the results of two clinical studies designed to evaluate the safety of high doses of P.