Abstract
Results of microbiological assays on a large number of oligosaccharides obtained from human milk and on simple derivatives (disaccharides or simple synthetic compounds) of N-acetyl-D-glucosamine are reported. The high microbiological activity of 4-O-beta-D-galactopyranosyl-N -acetyl-D-glucosamine and of ethyl- and n-propyl-N-acetyl-beta-D-glucosamine has not been exceeded by any other compound tested. The "true" specific bifidus factor has either still to be found or several related compounds may act as precursors or in synergistic combination.