Short-chain fatty acid and organic acid concentrations in feces of 10 human volunteers and their correlation with anaerobe cultural over a 15-month period.

Short-chain fatty acid (SCFA) and organic acid concentrations were determined with gas-liquid chromatography (GLC) in fresh feces from 10 healthy volunteers, simultaneously with their fecal cultural counts. To find a simple and reliable method to detect disturbances in fecal flora, we calculated the intraindividual correlations between the concentrations determined by GLC and the fecal cultural counts. Twenty-three (4.7%) significant (P less than 0.05) linear correlations were thus found in nine of the volunteers. Using multivariate analysis, we attempted to assign fecal samples to individuals in accordance with their SCFA, cultural count, and organic acid profiles. Percentages of samples thus classified correctly were 49, 39, and 29, respectively. We conclude from this study that these percentages represent the normal situation in a group of healthy humans and that the low percentage of significant correlation coefficients shows that the relation between fecal SCFA/organic acid concentrations and fecal cultural counts has not been established.