Breast Milk as a Source of Prebiotic Human Milk Oligosaccharides and Bacteria from the Lactobacillaceae Family.

Breast milk, as the optimal food for infants and young children, contains all the components necessary for proper growth and development. It is a rich source of both essential nutrients and biologically active factors, making breast milk a unique food with scientifically proven health-promoting properties. Among the entire range of biologically active factors, breast milk microorganisms and prebiotic factors, in the form of breast milk oligosaccharides, occupy an important place. The aim of our research was to determine the occurrence of bacteria with probiotic potential, belonging to the Lactobacillaceae family, in the environment of breast milk and breast milk oligosaccharides. The study included 63 human milk samples from breastfeeding women at various stages of lactation. Microorganism identification based on culture tests and MALDI TOF/MS, macronutrient analysis using the MIRIS human milk analyser, as well as analysis of human milk oligosaccharides using ultra-high-performance liquid chromatography coupled with high-resolution mass spectrometry were performed. The results have shown that breast milk from different breastfeeding women is characterized by great diversity in terms of the presence of Lacto-bacillaceae bacteria in its microbiological composition. These bacteria were present in 22.2 % of the tested breast milk samples. Analysis of the human milk oligosaccharide profile revealed a slightly higher content of prebiotic factors in breast milk samples containing Lactobacillaceae, including 2'-fucosyllactose, oligosaccharide occurring in the highest amount in breast milk.