Lacto-N-neotetraose (LNnT / neo-LNT)

Lacto-N-neotetraose  (LNnT, Galβ1-4GlcNAcβ1-3Galβ1-4Glc) ranks as the second most abundant neutral human milk oligosaccharide (HMO) after 2'-FL, comprising 9-15% of total HMOs in mature breast milk and appearing as a white hygroscopic powder critical for infant intestinal barrier development and microbiota orchestration. Commercially produced via precision microbial fermentation in engineered E. coli (>99% purity, GRAS by FDA/EFSA/TGA), this tetrasaccharide selectively stimulates Bifidobacterium bifidum/longum proliferation (3-5x growth vs glucose), inhibits pathogen adhesion (E. coli, C. jejuni by 70-90%), upregulates tight junctions (ZO-1/claudin-1), reduces necrotizing enterocolitis (NEC) incidence by 50% in preclinical models, and supports neurodevelopment through ganglioside mimicry; its type 2 chain structure enables fucosylation to Le^x and sialylation to DSLnT, with exceptional water solubility (800 g/L), hydrolytic stability (pH 3-9), and 60-month shelf life making it ideal for infant formula fortification and functional foods. Appearance White to off-white hygroscopic amorphous powder. ​ Highly soluble >800 g/L in water at 25°C. ​ Source 9-15% total HMOs in mature human milk; minor in colostrum (~6%). ​ Microbial fermentation using β4GalT/β3GnT-engineered E. coli BL21. ​ Molecular Weight and Structure 707.63 g/mol, formula C₂₆H₄₅NO₂₁ (CAS 13007-32-4). Galβ1-4GlcNAcβ1-3Galβ1-4Glc type 2 chain tetrasaccharide. ​ Sugar Specificity Bifidobacterium β3GnTase/β4GalTase; precursor for Le^x (FucT3). ​ Binds DC-SIGN, selectins; resistant to human α-fucosidase. ​ Biological Activity Amplifies Bifidobacterium growth 3-5x; inhibits E. coli/C. jejuni adhesion 70-90%. ​ Upregulates ZO-1/claudin-1; reduces TNF-α/IL-8 in IEC-6 cells. ​ Purity and Microbial Contamination ≥99% HPLC/NMR; lactose <0.5%, 2'-FL <1%. ​ Endotoxins <10 EU/g; total aerobes <10 CFU/g; yeast/mold absent. ​ Identity and Quality Control ¹H-NMR structural confirmation; optical rotation +33° to +27°. ​ LC-MS [M+H]+ 708.3; HPAEC monosaccharide profile. ​ Shelf Life and Storage 60 months at 25°C/60% RH sealed; 5 years -20°C. ​ Hygroscopic—store desiccated under nitrogen. ​ Applications Infant formula enrichment (up to 1.5 g/L); functional foods. ​ NEC therapeutics; microbiota modulation research. ​ Key Characteristics Type 2 chain HMO scaffold; gastric stable (pH 3-9). ​ Bifido-selective fermentation yielding acetate/propionate. ​ Citation Links https://pubchem.ncbi.nlm.nih.gov/compound/121853 ​ https://www.chemicalbook.com/ChemicalProductProperty_EN_CB1418097.htm ​ https://www.fda.gov/media/100020/download ​ https://www.tga.gov.au/resources/resources/compositional-guidelines/lacto-n-neotetraose ​ https://www.sciencedirect.com/science/article/abs/pii/S0141022921001708 ​ https://www.medchemexpress.com/lacto-n-neotetraose.html ​ https://pubchem.ncbi.nlm.nih.gov/compound/21670519 ​ https://en.wikipedia.org/wiki/Lacto-N-tetraose ​ https://www.vulcanchem.com/product/main-products/14116-68-8 ​ https://contaminantdb.ca/contaminants/CHEM027179 ​