Abstract: Breast milk is rich in human milk oligosaccharides (HMOs), which are prebiotics that can stimulate the growth of beneficial bacteria in the neonatal intestine. At present, the oligosaccharides allowed to be added to infant formula in China are structurally different from HMOs so that they cannot simulate some structure-specific effects of HMOs. This review describes the composition, structure and content of HMOs in breast milk, focusing on the relationship between HMOs as well as their metabolites and the infant intestinal microbiota. Finally, the beneficial effects of feeding infant formula with HMOs on the infant intestinal flora are discussed, which will provide theoretical support for promoting the application of HMOs in infant formula foods.

Key words: human milk oligosaccharides; compositional structure; infant; gut microbiome; correlation; metabolites