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Milk Oligosaccharides (milk + oligosaccharide)
Kinds of Milk Oligosaccharides Selected AbstractsAssessment of the Two Helicobacter pylori ,-1,3-Fucosyltransferase Ortholog Genes for the Large-Scale Synthesis of LewisX Human Milk Oligosaccharides by Metabolically Engineered Escherichia coliBIOTECHNOLOGY PROGRESS, Issue 2 2004Claire Dumon We previously described a bacterial fermentation process for the in vivo conversion of lactose into fucosylated derivatives of lacto- N -neotetraose Gal(,1,4)GlcNAc(,1,3)Gal(,1,4)Glc (LNnT). The major product obtained was lacto- N -neofucopentaose-V Gal(,1,4)GlcNAc(,1,3)Gal(,1,4)[Fuc(,1,3)]Glc, carrying fucose on the glucosyl residue of LNnT. Only a small amount of oligosaccharides fucosylated on N -acetylglucosaminyl residues and thus carrying the LewisX group (LeX) was also produced. We report here a fermentation process for the large-scale production of LeX oligosaccharides. The two fucosyltransferase genes futA and futB of Helicobacter pylori (strain 26695) were compared in order to optimize fucosylation in vivo. futA was found to provide the best activity on the LNnT acceptor, whereas futB expressed a better LeX activity in vitro. Both genes were expressed to produce oligosaccharides in engineered Escherichia coli ( E. coli) cells. The fucosylation pattern of the recombinant oligosaccharides was closely correlated with the specificity observed in vitro, FutB favoring the formation of LeX carrying oligosaccharides. Lacto- N -neodifucohexaose-II Gal(,1,4)[Fuc(,1,3)]GlcNAc(,1,3)Gal(,1,4)[Fuc(,1,3)]Glc represented 70% of the total oligosaccharide amount of futA -on-driven fermentation and was produced at a concentration of 1.7 g/L. Fermentation driven by futBled to equal amounts of both lacto- N -neofucopentaose-V and lacto- N -neofucopentaose-II Gal(,1,4)[Fuc(,1,3)]GlcNAc(,1,3)Gal(,1,4)Glc, produced at 280 and 260 mg/L, respectively. Unexpectedly, a noticeable proportion (0.5 g/L) of the human milk oligosaccharide 3-fucosyllactose Gal(,1,4)[Fuc(,1,3)]Glc was produced in futA -on-driven fermentation, underlining the activity of fucosyltransferase FutA in E.coli and leading to a reassessment of its activity on lactose. All oligosaccharides produced by the products of both fut genes were natural compounds of human milk. [source] CE-LIF-MSn profiling of oligosaccharides in human milk and feces of breast-fed babiesELECTROPHORESIS, Issue 7 2010Simone Albrecht Abstract Mixtures of the complex human milk oligosaccharides (HMOs) are difficult to analyze and gastrointestinal bioconversion products of HMOs may complicate analysis even more. Their analysis, therefore, requires the combination of a sensitive and high-resolution separation technique with a mass identification tool. This study introduces for the first time the hyphenation of CE with an electrospray mass spectrometer, capable to perform multiple MS analysis (ESI-MSn) for the separation and characterization of HMOs in breast milk and feces of breast-fed babies. LIF was used for on- and off-line detections. From the overall 47 peaks detected in off-line CE-LIF electropherograms, 21 peaks could be unambiguously and 11 peaks could be tentatively assigned. The detailed structural characterization of a novel lacto- N -neo-tetraose isomer and a novel lacto- N -fucopentaose isomer was established in baby feces and pointed to gastrointestinal hydrolysis of higher-Mw HMOs. CE-LIF-ESI-MSn presents, therefore, a useful tool which contributes to an advanced understanding on the fate of individual HMOs during their gastrointestinal passage. [source] A specific mixture of short-chain galacto-oligosaccharides and long-chain fructo-oligosaccharides induces a beneficial immunoglobulin profile in infants at high risk for allergyALLERGY, Issue 3 2009E. Van Hoffen Background:, It has been suggested that human breast milk oligosaccharides play a role in the development of the immune system in infants, and may consequently inhibit the onset of allergy. A specific prebiotic mixture of short-chain galacto-oligosaccharides and long-chain fructo-oligosaccharides (GOS/FOS) has been shown to reduce the incidence of atopic dermatitis (AD) at 6 months of age in infants at risk for allergy. Aim of the study:, This study was aimed to analyze the effect of GOS/FOS on the immune response in these infants. Methods:, In a double-blind randomized placebo-controlled study, infants received a hypoallergenic whey formula with either 8 g/l GOS/FOS in a 9 : 1 ratio (IMMUNOFORTISTM) or 8 g/l maltodextrine (placebo) for 6 months. At 3 months of age, children were vaccinated with Hexavac against a.o. diphteria, tetanus, polio (DTP). At 6 months of age, plasma samples were collected from 84 infants (verum group n = 41, placebo group n = 43). Levels of total immunoglobulins (Ig) and of cow's milk protein (CMP-) and DTP-specific Ig were measured. Results:, GOS/FOS supplementation led to a significant reduction in the plasma level of total IgE, IgG1, IgG2 and IgG3, whereas no effect on IgG4 was observed. CMP-specific IgG1 was significantly decreased. DTP-specific Ig levels were not affected. Conclusions:, This study shows that GOS/FOS supplementation induces a beneficial antibody profile. GOS/FOS reduces the total Ig response and modulates the immune response towards CMP, while leaving the response to vaccination intact. This suggests that oral GOS/FOS supplementation is a safe method to restrain the atopic march. [source] In vitro fermentability of human milk oligosaccharides by several strains of bifidobacteriaMOLECULAR NUTRITION & FOOD RESEARCH (FORMERLY NAHRUNG/FOOD), Issue 11 2007Robert E. Ward Abstract This study was conducted to investigate the catabolism and fermentation of human milk oligosaccharides (HMO) by individual strains of bifidobacteria. Oligosaccharides were isolated from a pooled sample of human milk using solid-phase extraction, and then added to a growth medium as the sole source of fermentable carbohydrate. Of five strains of bifidobacteria tested (Bifidobacterium longum biovar infantis, Bifidobacterium bifidum, Bifidobacterium longum biovar longum, Bifidobacterium breve, and Bifidobacterium adolescentis), B. longum bv. infantis grew better, achieving triple the cell density then the other strains. B. bifidum did not reach a high cell density, yet generated free sialic acid, fucose and N-acetylglucosamine in the media, suggesting some capacity for HMO degradation. Thin layer chromatography profiles of spent fermentation broth suggests substantial degradation of oligosaccharides by B. longum bv. infantis, moderate degradation by B. bifidum and little degradation by other strains. While all strains were able to individually ferment two monosaccharide constituents of HMO, glucose and galactose, only B. longum bv. infantis and B. breve were able to ferment glucosamine, fucose and sialic acid. These results suggest that as a potential prebiotic, HMO may selectively promote the growth of certain bifidobacteria strains, and their catabolism may result in free monosaccharides in the colonic lumen. [source] The effect of prebiotics in the management of neonatal hyperbilirubinaemiaACTA PAEDIATRICA, Issue 10 2009M Bisceglia Abstract Background:, Breast milk oligosaccharides such as galacto-oligosaccharides (scGOS) and fructo-oligosaccharides (lcFOS) can influence the intestinal microbial flora. The latter, in turn, can modulate several intestinal and extraintestinal functions, including bilirubin metabolism. Supplementing infant formula with a prebiotic mixture might then be a novel and safe intervention to manage mild neonatal hyperbilirubinaemia. Aim:, To investigate the effect of dietary supplementation with prebiotics on moderate hyperbilirubinaemia in healthy, term infants. Methods:, A prospective, double-blind, clinical trial was performed on seventy-six consecutive newborns who were randomly assigned to receive a formula containing 0.8 g/dL of a mixture from scGOS and lcFOS (ratio 9:1), or maltodextrines as placebo for 28 days. Bilirubin levels were determined by the transcutaneous bilirubin measurement within 2 h after birth (T1), at 24, 48 and 72 h and at 5, 7, 10 and 28 days of life. The number of stool per day was also recorded. Results:, Neonates receiving prebiotics showed a larger number of stools over all the duration of dietary intervention compared to that of those on placebo (Repeated Measures ANOVA p < 0.001; day 28 3.4 ± 0.0.9 vs 1.7 ± 0.9, respectively; Dunn test p < 0.05). Neonates whose formula was supplemented with prebiotics showed a lower transcutaneous bilirubin that was statistically significant from 72 h of life (5.46 ± 1.6 vs 7.07 ± 2.49, post hoc Dunn test, p < 0.05) throughout the duration of the dietary intervention (day 28 2.41 ± 0.4 vs 2.85 ± 0.5, post hoc Dunn test, p < 0.05). Conclusion:, The addition of prebiotics to standard infant diet might represent a novel strategy to help control neonatal hyperbilirubinaemia. [source] Reproducing the bifidogenic effect of human milk in formula-fed infants: Why and how?ACTA PAEDIATRICA, Issue 2005Guido E Moro Abstract Awareness of the key role of the intestinal microflora in the generation of the immunophysiological regulation and in the defence against pathogenic agents has attracted our interest in ways of manipulating the microbiota to improve health. Dietary modulation of the intestinal microflora is today one of the main topics of interest in the nutritional sciences. Performing this modulation in the neonatal or early infancy period, when immunological programming takes place, is a relatively new concept. Fructo-oligosaccharides (FOS) and galacto-oligosaccharides (GOS) are prebiotics whose bifidogenic activity has been proven in adults. However, only recently have they been combined in infant formulas to reproduce the prebiotic effect of human milk oligosaccharides. In two consecutive trials, it has been demonstrated that supplementation of infant formulas with a mixture of GOS and FOS modified the fecal flora of term and preterm infants, stimulating the growth of Bifidobacteria. In the trial with term infants, the bifidogenic effect of the prebiotic mixture was dose dependent and there was also a significant increase in the number of Lactobacilli in the supplemented group. These findings offer a promising horizon for the early prevention of allergy and infections in infants. [source] |