The establishment of some microflora associated biochemical characteristics in feces from children during the first years of life.

This report presents a new approach to the study of the colonization of the digestive tract after birth. We have examined the development of four microflora associated characteristics, MACs, defined as the recording of any anatomical structure, biochemical or physiological function in the macroorganism, which has been influenced by the microflora. These MACs may create a basis for later investigations into the impact of diarrheal diseases and antibiotic therapy. The following biochemical characteristics were studied in feces from children of 0-61 months of age: conversion of cholesterol to coprostanol and bilirubin to urobilins, inactivation of trypsin and degradation of mucin. These results indicate establishment of microbes capable of converting bilirubin to urobilins within the second year of life. The mucin degrading and cholesterol converting microbes are established in most of the children during the same period. Tryptic activity was found to be absent in meconium, present in feces from all children up to 21 months of age, and absent in 6 out of 15 children in the age group 46-61 months. The study indicates that the establishment of the MACs in the digestive tract is a remarkably long drawn out process.