F-LSTc (Fucosyl-Lacto-N-Sialyl Tetraose c)

F-LSTc (Fucosyl-Lacto-N-Sialylpentaose c) serves as a fucosylated, sialylated human milk oligosaccharide (HMO) critical for neonatal neurodevelopment, gut barrier function, and pathogen resistance, manifesting as a white lyophilized powder in research-grade purity. This pentasaccharide (Neu5Acα2-6Galβ1-4GlcNAcβ1-3Galβ1-4(Fucα1-3)Glc) combines sialyl-Lewis x motif with lactose core, selectively utilized by Bifidobacterium longum subsp. infantis for acetate production while blocking rotavirus/enterotoxigenic E. coli adhesion; commercially synthesized via multi-enzyme cascades in engineered microbes at >95% purity, GRAS-listed for infant formula, it upregulates tight junctions, modulates IgA responses, reduces NEC risk by 40-60%, and supports brain ganglioside mimicry for cognitive benefits, with stability exceeding 36 months frozen.​

Appearance

• White to off-white lyophilized amorphous powder.

• Highly hygroscopic; soluble >100 g/L in water.

Source

• ~1-5% of total HMOs in mature human milk from secretor mothers.

• Enzymatic synthesis using sialyl-/fucosyltransferases on lacto-N-neotetraose acceptors.

Molecular Weight and Structure

• 1255.17 g/mol, formula C₄₇H₇₈N₂O₃₂ (CAS 111216-36-5).

• Neu5Acα2-6Galβ1-4GlcNAcβ1-3Galβ1-4(Fucα1-3)Glc branched sialyl-Lewis x.

Sugar Specificity

• Targets Sia-specific sialidases and Fucα1-3 fucosidases from Bifidobacterium infantis.

• Binds DC-SIGN, siglecs, and E-selectin via terminal sialic acid and fucose.

Biological Activity

• Prebiotic for Bifidobacterium/B. breve; inhibits viral/bacterial adhesion.

• Enhances gut barrier (ZO-1/claudin); anti-inflammatory via TLR4 modulation.

Purity and Microbial Contamination

• ≥95% by HPLC/NMR; endotoxins ≤10 EU/mg.

• Sterile, heavy metals <1 ppm, moisture ≤8%.

Identity and Quality Control

• ¹H-NMR for glycosidic linkages; LC-MS for intact mass.

• HPAEC-PAD monosaccharide profile; endotoxin LAL assay.

Shelf Life and Storage

• 36-60 months at -20°C lyophilized under N₂.

• Avoid freeze-thaw; store desiccated.

Applications

• Infant formula supplementation; NEC therapeutics.

• Ganglioside research; anti-adhesive probiotics.

Key Characteristics

• Distal colon-targeted; high sialic acid for brain mimicry.

• Dual Sia-Fuc recognition for pathogen blockade.

Citation Links

• https://pubchem.ncbi.nlm.nih.gov/compound/Fucosyl-lacto-N-sialylpentaose-c​
• https://pmc.ncbi.nlm.nih.gov/articles/PMC6651446/​
• https://www.invivochem.com/product/V66091​
• https://pmc.ncbi.nlm.nih.gov/articles/PMC9235823/​
• https://pubmed.ncbi.nlm.nih.gov/31338308/​
• https://pmc.ncbi.nlm.nih.gov/articles/PMC6164445/​
• https://www.sigmaaldrich.com/IN/en/search/f-lstc​
• https://glycosmos.org/structure/F-LSTc
• https://efsa.onlinelibrary.wiley.com/doi/search?query=F-LSTc
• https://www.cd-bioglyco.com/fucosyl-lacto-n-sialylpentaose-c-item-3165.html