The invention relates to probiotic micro-organisms isolated from faeces of children exclusively fed with breast milk. Said microorganisms are used in the food or pharmaceutical industry, especially for use in infant formula milk, due to their probiotic properties which have beneficial effects on the health of those ingesting them. Said microorganisms consist of Lactobacillus rhamnosus HERO 22A (CNCM I-4036), Lactobacillus paracasei HERO 7 (CNCM I-4034) and Bifidobacterium breve HERO 15B (CNCM I-4035).