4'-GALACTOSYLLACTOSE NEW

4'-Galactosyllactose (4'-GL) is a trisaccharide and a minor human milk oligosaccharide (HMO) with the structure Gal(β1-4)Gal(β1-4)Glc. Here's a detailed breakdown of its properties and significance:

1. Chemical Structure

• Composition:

• Glucose (Glc) + Galactose (Gal) + Galactose (Gal).

• Linkages:

• Lactose core: Gal(β1-4)Glc (at reducing end).

• Additional Gal: Linked via β1-4 bond to the glucose moiety of lactose.

• Systematic Name:
  O-β-D-Galactopyranosyl-(1→4)-O-β-D-galactopyranosyl-(1→4)-D-glucopyranose.

2. Natural Occurrence

• Human Milk:

• Present in trace amounts (≤0.1 g/L), making it a minor HMO compared to dominant types like 2'-FL or LNT.

• Function in Infants:

• Acts as a prebiotic to nourish beneficial gut bacteria (Bifidobacterium spp.).

• Blocks pathogen adhesion (e.g., Campylobacter, E. coli) to intestinal cells.

• Supports immune development.

3. Biological Significance

• Prebiotic Activity:
  Fermented by gut microbiota to produce short-chain fatty acids (e.g., acetate), promoting gut health.

• Anti-Infective Properties:
  Mimics host cell receptors, preventing bacterial/viral binding.

• Immune Modulation:
  May regulate cytokine production and reduce inflammation.

4. Synthesis & Production

• Enzymatic Synthesis:
  Produced using β-galactosidases or glycosyltransferases from lactose + galactose donors.

• Commercial Relevance:
  Added to infant formula (often as part of HMO blends) to mimic breast milk benefits.