Hospital-Campus-College-London-Sw-Kingdom-o

Breast milk prebiotic oligosaccharides are believed to promote enteral tolerance. Many mothers delivering preterm are unable to provide sufficient milk. We conducted a multicenter, randomized, controlled trial comparing preterm formula containing g0 mL short-chain galacto-oligosaccharideslong-chain fructo-oligosaccharides in a 91 ratio and an otherwise identical formula, using formula only to augment insufficient maternal milk volume. Infants were randomized within 24 h of birth. The primary outcome (PO) was time to establish a total milk intake of 1 mLkgd PO and the principal secondary outcome (PSO) was proportion of time between birth and 28 ddischarge that a total milk intake of ≥ 1 mLkgd was tolerated. Other secondary outcomes included growth, fecal characteristics, gastrointestinal signs, necrotizing enterocolitis, and bloodstream infection.

Outcomes were compared adjusted for prespecified covariates. We recruited 1 infants appropriately grown for GA 33 wk. There were no significant differences in PO or PSOs. After covariate adjustment, we showed significant benefit from trial formula in PSO with increasing infant immaturity (2% improved tolerance for a baby born at 28-wk gestation and 9% at 26-wk gestation; p 01) but decreased or no benefit in babies 31-wk gestation. Prebiotic supplementation appears safe and may benefit enteral tolerance in the most immature infants.Structural basis for broad substrate specificity of UDP-glucose 4-epimerase in the human milk oligosaccharide catabolic pathway of Bifidobacterium longum.Nam YW(1)(2), Nishimoto M(3), Arakawa T(1)(4), Kitaoka M(3)(5), Fushinobu Research Center, Chapman University School of Pharmacy, Irvine, CA 92618, USA.

Infant gut-associated bifidobacteria has a metabolic pathway that specifically utilizes lacto-N-biose I (Gal-β1,3-GlcNAc) and galacto-N-biose (Gal-β1,3-GalNAc) from human milk and mucin glycans. UDP-glucose 4-epimerase (GalE) from Bifidobacterium longum (bGalE) catalyzes epimerization reactions of UDP-Gal into UDP-Glc and UDP-GalNAc into UDP-GlcNAc with the same level of activity that is required to send galacto-hexoses into glycolysis. Here, we determined the crystal structures of bGalE in three ternary complex forms NAD+UDP, NAD+UDP-GlcNAc, and NAD+UDP-Glc. The broad specificity of bGalE was explained by structural features of the binding pocket for the N-acetyl or C2 hydroxy group of the substrate. Asn0 is located in lacto-n-neotetraose of the C2 group, and its side chain adopts different conformations in the complex structures with UDP-Glc and UDP-GlcNAc. On the other side, Cys299 forms a large pocket for the C5 sugar ring atom. lacto-n-neotetraose and the large C5 pocket of bGalE are suitable for accommodating both the hydroxy and N-acetyl groups of the substrate during sugar ring rotation in the catalytic cycle.

The substrate specificity and active site structure of bGalE were distinct from those of Esherichia coli GalE but Conflict of interest statement The authors declare no competing interests.Identification of Oligosaccharides in Feces of Breast-fed Infants and Their Correlation with the Gut Microbial Community.Davis JC(1), Totten SM(1), Huang JO(2), Nagshbandi S(2), Kirmiz N(3), Garrido DA(4), Lewis ZT(3), Wu LD(1), Smilowitz JT(3), German JB(3), Mills DA(5), California 95616; §Foods for Health Institute, University of California, Davis, 95616; ¶Department of Food Science and Technology, University of California, 95616; ‖Department of Viticulture and Enology, University of California, Davis, 95616; ¶Department of Food Science and Technology, University of California, Davis, California 95616; ‖Department of Viticulture and Enology, University of California 95616; §Foods for Health Institute, University of California, Davis, Glycans in breast milk are abundant and found as either free oligosaccharides or conjugated to proteins and lipids. Free human milk oligosaccharides (HMOs) function as prebiotics by stimulating the growth of beneficial bacteria while preventing the binding of harmful bacteria to intestinal epithelial cells. Bacteria have adapted to the glycan-rich environment of the gut by developing enzymes that catabolize glycans. The decrease in HMOs and the increase in glycan digestion products give indications of the active enzymes in the microbial population. In this study, we quantitated the disappearance of intact HMOs and characterized the glycan digestion products in the gut that are produced by the action of microbial enzymes on HMOs and glycoconjugates from breast milk.

Oligosaccharides from fecal samples of exclusively breast-fed infants were extracted and profiled using nanoLC-MS. Intact HMOs were found in the fecal samples, additionally, other oligosaccharides were found corresponding to degraded HMOs and non-HMO based compounds.