Study on the prebiotic effects of 2′-Fucosyllactose in infants based on an in vitro spatiotemporal dynamic digestion model

2′-Fucosyllactose(2′-FL) is a key component of human milk oligosaccharides (HMOs). This study employed an in vitro spatiotemporal dynamic digestion model (BGR-7) to systematically investigate the structural changes, gut microbiota modulation, and metabolic regulatory effects of 2′-FL. 2′-FL remains structurally stable in the stomach and small intestine but undergoes significant degradation in the colon. It promotes the enrichment of beneficial bacteria such as Bifidobacterium and Bacteroides , inhibits the overgrowth of harmful bacteria including Streptococcus, Enterococcus, and Escherichia-Shigella , and exerts flexible regulatory effects on opportunistic pathogens such as Klebsiella, Citrobacter, and Enterobacter . 2′-FL increases levels of intestinal gases such as CO 2 , H 2 , VOCs and H 2 S, with VOCs and H 2 S exhibiting distinct spatiotemporal patterns. Metabolomic analysis indicates that it influences pathways including sulfur metabolism, the tricarboxylic acid cycle, and glutathione metabolism, thereby enhancing antioxidant and energy metabolism capabilities. In summary, 2′-FL promotes the establishment of a dynamically balanced intestinal microenvironment in infants by regulating microbial community structure and metabolic function. Its regulatory pattern differs from that of fructooligosaccharides (FOS), exhibiting more complex temporal and ecological characteristics. The findings of this study provide experimental evidence to elucidate the role of HMOs in infant intestinal health.