Effects of bovine alpha-lactalbumin and casein glycomacropeptide-enriched infant formulae on faecal microbiota in healthy term infants

J Pediatr Gastroenterol Nutr. 2006 Nov;43(5):673-9. doi: 10.1097/01.mpg.0000232019.79025.8f.


Objective: Certain milk factors may promote the growth of a host-friendly gastrointestinal microbiota, for example, one that is predominated by bifidobacteria, a perceived health-promoting genus. This may explain why breast-fed infants experience fewer intestinal infections than their formula-fed counterparts who are believed to have a more diverse microbiota, which is similar to that of adults. The effects of formulas supplemented with 2 such ingredients from bovine milk, alpha-lactalbumin (alpha-lac) and casein glycomacropeptide (GMP), on gut flora were investigated in this study.

Patients and methods: Six-week-old (4-8 wk), healthy term infants were randomised to a standard infant formula or 1 of 2 test formulae enriched in alpha-lac with higher or lower GMP until 6 months. Faecal bacteriology was determined by the culture-independent procedure fluorescence in situ hybridisation.

Results: There was a large fluctuation of bacterial counts within groups with no statistically significant differences between groups. Although all groups showed a predominance of bifidobacteria, breast-fed infants had a small temporary increase in counts. Other bacterial levels varied in formula-fed groups, which overall showed an adult-like faecal microflora.

Conclusions: It can be speculated that a prebiotic effect for alpha-lac and GMP is achieved only with low starting populations of beneficial microbiota (eg, infants not initially breast-fed.

Publication types

  • Randomized Controlled Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Caseins / administration & dosage*
  • Cattle
  • Colony Count, Microbial
  • Double-Blind Method
  • Feces / microbiology*
  • Glycopeptides
  • Humans
  • In Situ Hybridization, Fluorescence
  • Infant
  • Infant Formula* / chemistry
  • Lactalbumin / administration & dosage*
  • Milk, Human* / chemistry
  • Weaning


  • Caseins
  • Glycopeptides
  • Lactalbumin