Abstract
Faecal samples of six healthy breast-fed, or formula-fed, infants were collected at intervals up to 9 mth of age and analysed for their contents of sphingolipids. Comparisons were made with faecal samples of one older child and one adult. The mean faecal content of sphingolipids during the first 9 mth of life (8.2 μmol sphingosine/g dry stool) was significantly less than that of meconium samples (23.3μmol/g) but higher than that of adult stools (1.2μmol/g). Sphingomyelin excretion was generally less than 10 per cent of total sphingolipid excretion with a mean of about 5 per cent. Exclusively breast-fed children excreted non-degraded blood group ABH and Lewis active intestinal glycolipids during the first 2–3 mth but after that time a partial degradation of these substances was seen. Whenever formula or solid food was introduced, irrespective of continued breast-feeding, the excretion of blood group-active fucolipids and gangliosides became less apparent and instead lactosylceramide became the single dominating faecal glycolipid. The mucin and short chain fatty acid content of these specific faecal samples were recently presented.30 Bacterial glycosidascs are likely to be responsible for the degradation of specific glycolipids and faecal glycosphingolipid excretion seems to be a sensitive parameter for studying the establishment of subset(s) of the intestinal non-pathogenic microflora functionally specialised in degrading oligosaccharide chains.