Human milk oligosaccharides, representing the third largest fraction of human milk, have been assigned important protective functions for newborns acting as bifidogenic substrates or as inhibitory agents towards pathogens. Using high-pH anion-exchange chromatography and an enzyme test kit, twenty oligosaccharides and lactose were determined in milk samples of German women from days 3 to 90 postpartum. Twenty-two secretor mothers with Lewis blood group Le(a - b+) synthesised all twenty oligosaccharides, and could be assigned to milk group 1. Five non-secretor mothers (Le(a+b - )) produced all oligosaccharides with the exception of α1,2-fucosylated compounds (milk group 2), whereas three secretor mothers with blood type Le(a - b - ) lacked α1,4-fucosyloligosaccharides, corresponding to milk group 3. Secretor women of milk groups 1 and 3 synthesised significantly higher amounts of total neutral oligosaccharides and of several total core structures (e.g. lacto-N-tetraose) than non-secretor women. Generally, these oligosaccharides significantly decrease during the first 3 months postpartum. By comparing fucosyloligosaccharides within and among the three milk groups, insight into their biosynthesis could be gained. Six acidic oligosaccharides without fucose residues were detected in milk samples of all mothers. Regression analysis confirmed that total acidic oligosaccharides declined threefold during the study period. Milk samples corresponding to the three milk groups exhibited significant qualitative and quantitative differences during the first 3 months of lactation. It can be assumed that particularly milk of non-secretor women (milk group 2) exerts a modified biological protection in the babies in comparison with milks of secretors (groups 1 and 3).

Background: Oligosaccharides may alter postnatal immune development by influencing the constitution of gastrointestinal bacterial flora. Aims: To investigate the effect of a prebiotic mixture of galacto-and long chain fructo-oligosaccharides on the incidence of atopic dermatitis (AD) during the first six months of life in formula fed infants at high risk of atopy. Methods: Prospective, double-blind, randomised, placebo controlled trial; 259 infants at risk for atopy were enrolled. A total of 102 infants in the prebiotic group and 104 infants in the placebo group completed the study. If bottle feeding was started, the infant was randomly assigned to one of two hydrolysed protein formula groups (0.8 g/100 ml prebiotics or maltodextrine as placebo). All infants were examined for clinical evidence of atopic dermatitis. In a subgroup of 98 infants, faecal flora was analysed. Results: Ten infants (9.8%; 95 CI 5.4-17.1%) in the intervention group and 24 infants (23.1%; 95 CI 16.0-32.1%) in the control group developed AD. The severity of the dermatitis was not affected by diet. Prebiotic supplements were associated with a significantly higher number of faecal bifidobacteria compared with controls but there was no significant difference in lactobacilli counts. Conclusion: Results show for the first time a beneficial effect of prebiotics on the development of atopic dermatitis in a high risk population of infants. Although the mechanism of this effect requires further investigation, it appears likely that oligosaccharides modulate postnatal immune development by altering bowel flora and have a potential role in primary allergy prevention during infancy.

These data indicate that supplementation of a term infant's formula with a mixture of galacto- and fructooligosaccharides has a dose-dependent stimulating effect on the growth of Bifidobacteria and Lactobacilli in the intestine and results in softer stool with increasing dosage of supplementation.

Background: The establishment of a balanced intestinal microflora which may protect against infection is desirable for the preterm infant. Objective: To investigate the effect of a preterm formula milk supplement consisting of oligosaccharides in similar proportions to human milk on the faecal flora and stool characteristics of preterm infants. Study design: To resemble the effect of human milk, an oligosaccharide mixture consisting of 90% galacto-oligosaccharides and 10% fructo-oligosaccharides was used to supplement a standard preterm formula at a concentration of 10 g/l. This supplemented formula was studied in 15 preterm infants, and the results were compared with those found in 15 infants fed a formula supplemented with maltodextrin as placebo. A group fed fortified mother's milk was investigated as a reference group (n = 12). On four days during a 28 day feeding period (1, 7, 14, and 28), the faecal flora was investigated, and stool characteristics, growth, and possible side effects were recorded. Results: During the study period, the number of bifidobacteria in the group fed the oligosaccharide supplemented formula increased to the upper range of bifidobacteria counts in the reference group. The difference between the supplemented and non-supplemented groups was highly significant (p = 0.0008). The stool characteristics were also influenced by the supplement: the stool frequency after 28 days was significantly lower in the control group than in the oligosaccharide supplemented group (p = 0.0079) and the reference group (p < 0.0001). Over the study period, the stool consistency in the control group became harder, but remained fairly stable in the other two groups. There was no effect of the different diets on the incidence of side effects (crying, regurgitation, vomiting) or on weight gain or length gain. Conclusion: Supplementing preterm formula with a mixture of galacto-and fructo-oligosaccharides at a concentration of 10 g/l stimulates the growth of bifidobacteria in the intestine and results in stool characteristics similar to those found in preterm infants fed human milk. Therefore prebiotic mixtures such as the one studied may help to improve intestinal tolerance to enteral feeding in preterm infants.

There was no difference in growth, crying, vomiting, and regurgitation patterns between the groups. In summary, acidic oligosaccharides from pectin hydrolysate are well tolerated as ingredient in infant formulae but do not affect intestinal microecology.