[The significance of fucosylated glycoconjugates of human milk in nutrition of newborns and infants].

Human milk is extremely complex secretion rich in biologically active glycoconjugates including free oligosaccharides, glycoproteins, glycolipids, and glycosaminoglycans. Alpha1-2-fucosylated glycoconjugates of human milk are component of the innate immune system and provide an additional defense for infants. Participation of fucosylated glycotopes in the inhibition of infections caused by some bacteria and/or viruses rely on blocking of lectin-receptors of pathogen. Free fucosylated glycoconjugates present in milk are recognized and bound by the lectin-receptors of bacteria and/or viruses, and prevent pathogens adhesion to host epithelial cells and development of infection. So far, the efficacy of fucosylated glycoconjugates of human milk in the inhibition of adhesion has been confirmed for Escherichia coli, Campylobacter jejuni, Salmonella enterica, Rotaviruses, HIV, and Noroviruses. In this process the secretor/nonsecretor status of mother plays an important role. This is particularly important for the women who are nonsecretors and whose milk does not contain α1-2-fucosylated glycoconjugates and has reduced anti-microbial properties. Fucosylated glycoconjugates of milk are also one of the energy sources for physiological bacterial flora (Bifidobacterium), and have a positive impact on the intestinal peristalsis, and indirectly stimulate the central nervous system of infants. Furthermore, compared to human milk, the content of fucosylated glycoconjugates of cow’s milk is very low and does not provide adequate protection. This fact is particularly important in terms of nutrition and should be taken into consideration when artificial mixtures based on cows’ milk are used. The paper presents the current state of knowledge on human milk glycoconjugates, particularly on α1-2-fucosylated free oligosaccharides and glycoproteins, and discusses the significance of fucosylated glycoconjugates of human milk in the nutrition of newborns and infants.