Current methods for the analysis of human milk oligosaccharides (HMOs) and their novel applications

The microflora in the gastrointestinal tract of an infant plays an important role in the development of the immune system. Human milk oligosaccharides (HMOs)have become the subject of considerable interest because they strongly influence the composition of the gut microflora. The structures of the HMOs are usually very complex and novel techniques such as porous graphitic carbon-liquid chromatography-mass spectrometry (PGC-LC-MS) now facilitate separation and identification of most of the isomers. In contrast, matrix assisted laser desorption ionization-time-of-flight-mass spectrometry (MALDI-TOF-MS) analysis may now generate fast profiles, but does not allow isomer separation. Application of these novel techniques allows more accurate studies of Lewis blood group determinants, phylogenetic differences in milk oligosaccharide composition and bacterial HMO consumption. Such studies will greatly enhance knowledge of the biological functions of HMOs.