Enumeration of Intestinal Bifidobacteria by Growth on a Semi-selective Medium and GLC Assay of Acetic Acid Production

Abstract

A method is described for the enumeration of bifidobacteria in faeces which consists of a dilution count on a semi-selective medium followed by assay of the amount of acetic acid produced under standard conditions. With one exception (Lactobacillus reuteri) the lactobacilli always produced less acetic acid than did the bifidobacteria. L. reuteri could be distinguished from the bifidobacteria by the high concentration of acetaldehyde which it produced.