The physiological significance of the bifidusflora and of the fecal lysozyme in breast-fed infants. A contribution to the microecology of the intestinal tract

The fecal microflora of the breast-fed infant consists of nearly 100% Bifidobacteria. The importance of this long-known and unique phenomen is still not clearly understood. Likewise, the presence of lysozyme in the feces of breast-fed infants, which is administered in significant amounts with the human milk is not adequately known. New hints and hypotheses concerning digestion in ruminants are cited. In ruminants Lysozyme c functions as digestive enzyme in the rumen. Lysozyme causes lysis of the bacterial cell membrane leading to the release of bacterial contents i.e. proteins. The proteins synthesised in bacteria are the main source of nitrogen for ruminants. The hypothesis is established, that the enormous amounts of Bifidobacteria in the colon of the human newborn can be made of use in a similar way. The lysozyme in the colon of breast-fed infants leads to lysis of Bifidobacteria in connection with tryptic digestive enzymes, in turn leading to release of proteins and protein substances. It has recently been demonstrated that catabolic products of these proteins can be absorbed in the colon. The same group has shown that lysis of Bifidobacteria can take place in the presence of lysozyme in connection with trypsin.