Fate-Milk-Oligosaccharides-Canal-Infants-Oligosaccharides-Mothers-Milk-m

Oligosaccharide profiles of milk from 16 breast-feeding mothers were compared with profiles of stool and urine from their infants. Results were compared with endogenous oligosaccharide profiles obtained from the urine and feces of age-, parity-, and gender-matched formula-fed infants. In all cases, oligosaccharides were extracted, purified, reduced, and separated into acidic and neutral species; the latter were perbenzoylated and subjected to reversed-phase high-performance liquid chromatography. Structures were determined by mass spectrometry after debenzoylation. Among breast-fed infants, concentrations of oligosaccharides were higher in feces than in mothers' milk, and much higher in feces than in urine. Urinary and fecal oligosaccharides from breast-fed infants resembled those in their mothers' milk.

Those from formula-fed infants did not resemble human milk oligosaccharides, were found at much lower concentrations, and probably resulted from remodeling of intestinal glycoconjugates or from intestinal bacteria. Most of the human milk oligosaccharides survived transit through the gut, and some were absorbed and then excreted into the urine intact, implying that inhibition of intestinal and urinary pathogens by human milk oligosaccharides is quite likely in breast-fed Recent progress on health effects and biosynthesis of two key sialylated human milk oligosaccharides, 3'-sialyllactose and 6'-sialyllactose.Wuxi, Jiangsu 214122, China; International Joint Laboratory on Food Safety, Human milk oligosaccharides (HMOs), the third major solid component in breast milk, are recognized as the first prebiotics for health benefits in infants. Sialylated HMOs are an important type of HMOs, accounting for approximately 13% of total HMOs. 3'-Sialyllactose (3'-SL) and 6'-sialyllactose (6'-SL) are two simplest sialylated HMOs. Both SLs display promising prebiotic effects, especially in promoting the proliferation of bifidobacteria and shaping the gut microbiota. SLs exhibit several health effects, including antiadhesive antimicrobial ability, antiviral activity, prevention of necrotizing enterocolitis, immunomodulatory activity, regulation of intestinal epithelial cell response, promotion of brain development, and cognition improvement.

Both SLs have been approved as Generally Recognized as Safe by the American Food and Drug Administration and are commercially added to infant formula. The biosynthesis of SLs using enzymatic or microbial approaches has been widely studied. The enzymatic synthesis of SLs can be realized by two types of enzymes, sialidases with trans-sialidase activity and sialyltransferases. Microbial synthesis can be achieved by the multiple recombinant bacteria in one-pot reaction, which express the enzymes involved in SL synthesis pathways separately or in combination, or by metabolically engineered strains in a fermentation process. In this article, the physiological properties of 3'-SL and 6'-SL are summarized in detail and the biosynthesis of these SLs via enzymatic and microbial synthesis is comprehensively reviewed.Conflict of interest statement Declaration of Competing Interest The authors Safety evaluation of a mixture of the human-identical milk oligosaccharides 2'-fucosyllactose and difucosyllactose.Phipps KR(1), Baldwin N(2), Lynch B(3), Flaxmer J(4), Šoltésová A(5), Gilby Technology Park, Ively Road, Farnborough, Hampshire, GU14LX, UK.

Electronic Technology Park, Ively Road, Farnborough, Hampshire, GU14LX, UK.Mississauga, Ontario, L5N 2X7, Canada.and Mazury in Olsztyn, Faculty of Food Science, Plac Cieszynski 1, -726, Human milk oligosaccharides (HMOs) are endogenous indigestible carbohydrates representing the largest compositional difference between human breastmilk and infant formula (IF). Two major HMOs in human breastmilk are 2'-fucosyllactose manufactured structurally identical versions of HMOs [known as human-identical milk oligosaccharides (HiMOs)] to better replicate the composition of human milk. As 2'-FL and DFL are always found together in human milk, a mixture of these HiMOs (2'-FLDFL) has been proposed for use in IF and as a food ingredient. Safety assessment of 2'-FLDFL included conduct of in vitro genotoxicity tests and a subchronic oral toxicity study. In the subchronic study, 2'-FLDFL (81 ratio) was administered to neonatal rats at doses up to  mgkg body weight (bw)day, once daily for days, followed by a 4-week recovery period.

Seebio 2'-FL received  mgkg bwday of an oligosaccharide already used in IF (fructooligosaccharide), for direct comparison with the high-dose 2'-FLDFL group. No evidence of genotoxicity was observed.