Human milk oligosaccharides (HMOs)

01Overview and value chain#

Markers EC: Novel Food Regulation (EU) 2015/2283 | OECD: Industrial biotechnology | Regulator: FDA (US), NHC/NMPA (China), EFSA (EU)

Human milk oligosaccharides (HMOs) are complex carbohydrates — the third-largest solid component of breast milk after lactose and lipids — that pass largely undigested through an infant’s upper gastrointestinal tract, instead serving as a selective substrate that feeds beneficial Bifidobacterium infantis and blocks pathogen attachment to the intestinal epithelium. Industrial synthesis is achieved via precision fermentation using genetically engineered non-pathogenic E. coli K-12 strains, along with yeasts such as Saccharomyces cerevisiae and Kluyveromyces lactis. DSM-Firmenich’s Glycom division continued expanding its HMO portfolio into Asia, announcing in March 2026 new regulatory approvals in China, Malaysia and Thailand covering Glycare 3SL 9001 (3’-sialyllactose) and additional 2’-FL/DFL, LNT and 6’-SL sodium salt products for infant nutrition. FrieslandCampina Ingredients secured regulatory approval for its Aequival 2’-FL ingredient in Thailand, extending its use from flavored milk drinks for older children into infant and follow-on formulas. Glycosyn announced in December 2024 the availability for licensing of its commercial high-titer HMO production strains and IP covering prebiotic, anti-inflammatory and anti-infective uses, with strains validated at large fermentation scale for 2’-FL, LNT, 3’-SL and 6’-SL. Novonesis is expanding HMOs beyond infant nutrition into general adult health, targeting immune, metabolic and gut-health applications through gummies, beverages, powders and supplements, backed by an in-house research program spanning in vitro, in vivo, gut-model and human clinical testing.

The key directions of human milk oligosaccharides are:

1. Fucosyltransferase strain engineering: inserting L-fucosyltransferase genes (typically from Helicobacter pylori or Dictyostelium discoideum) into producer strains to synthesize fucosylated HMOs such as 2’-FL.
2. Sialyltransferase strain engineering: inserting sialyltransferase genes and optimizing CMP-Neu5Ac (sialic acid donor) synthesis pathways for sialylated HMOs such as 3’-SL and 6’-SL.
3. Lactose-operon knockout: removing the lacZ, lacY and lacA genes from the producer strain’s genome so the bacterium cannot degrade the lactose acceptor, using it exclusively as a substrate for sugar attachment.
4. Endotoxin-free downstream purification: multi-stage ultrafiltration, ion-exchange desalting and activated-carbon treatment removing bacterial endotoxins and residual DNA to achieve food-grade purity.

Sectoral value chain#

[Engineered producer strains] ──> [Precision fermentation] ──> [Membrane-based downstream purification]
         │                                  │                                    │
  (E. coli K-12 /                   (Lactose + glucose                   (Filtration, endotoxin
   S. cerevisiae)                    as substrates)                       capture, desalting, carbon)
                                                                                    │
[Infant formula / dietary supplements] <── [Drying & crystallization] <── [Evaporation & concentration]

Value chain levels#

Cross-cutting technologies of the sector:

• Nucleotide-sugar metabolic engineering: optimizing intracellular GDP-L-fucose synthesis pathways (de novo and salvage) to sustain high lactose-fucosylation rates.
• Downstream desalting and ion exchange: multi-stage membrane electrodialysis and ion-exchange chromatography systems fully removing salts, trace nucleic acids and endotoxins from the fermented solution.
• Efflux transporter engineering: genetically inserting specific membrane transporters into producer cells to actively export synthesized HMOs from the cytoplasm into the culture medium, eliminating the need for cell lysis.

02US#

The United States leads in HMO consumption volume and the depth of clinical research into their effects on infant health as well as adult metabolic stability, cognitive function and gut health.

FDA GRAS approvals, Similac/Enfamil HMO adoption, Glycosyn’s licensing-ready production strains#

• FDA GRAS approvals: the US became the first country to approve commercial HMO use, with the FDA issuing GRAS (Generally Recognized as Safe) determinations for 2’-FL, LNnT, 3-FL, LNT, 3’-SL and 6’-SL from leading global producers.
• Mass infant-formula adoption: major US infant-formula brands (Similac from Abbott, Enfamil from Reckitt) have fully converted their premium product lines to formulations with mandatory 2’-FL and HMO-blend addition, bringing their protective properties closer to the breastfeeding gold standard.
• Glycosyn’s licensing-ready strains: announced in December 2024 the availability for licensing of its commercial high-titer HMO production strains and IP covering prebiotic, anti-inflammatory and anti-infective uses, with strains validated at large fermentation scale for 2’-FL, LNT, 3’-SL and 6’-SL.

03CN#

China is the world’s largest and fastest-growing target market for HMOs, with national health policy directly driving domestic infant-formula fortification standards.

2023 NHC approval milestone, February 2026 3’-SL approval, domestic fermentation foundry buildout#

• 2023 NHC approval milestone: China’s National Health Commission officially approved 2’-FL and LNnT for use as nutritional fortifiers in infant formula in October 2023, triggering immediate production launches across major Chinese infant-formula brands.
• February 2026 3’-SL approval: the NHC took a further regulatory step in February 2026, officially authorizing the sialylated oligosaccharide 3’-sialyllactose for infant nutrition, given sialic acid’s critical role in infant neural connection formation and brain development.
• Domestic fermentation foundry buildout: Chinese biotechnology companies are actively developing high-technology domestic foundries for fermentation-based HMO production, having successfully developed and certified proprietary E. coli strains for 2’-FL synthesis to reduce dependence on imported feedstock from Western producers.

04EU#

The European Union is the world’s leading R&D hub for HMO research and synthesis, with established scientific and production bases in Denmark and the Netherlands.

DSM-Firmenich’s Asia regulatory expansion, FrieslandCampina’s Aequival approvals, EFSA’s six-HMO blend authorization#

• DSM-Firmenich’s Asia regulatory expansion: DSM-Firmenich’s Glycom division continued expanding its HMO portfolio into Asia, announcing in March 2026 new regulatory approvals in China, Malaysia and Thailand covering Glycare 3SL 9001 (3’-sialyllactose) and additional 2’-FL/DFL, LNT and 6’-SL sodium salt products for infant nutrition.
• FrieslandCampina’s Aequival approvals: secured regulatory approval for its Aequival 2’-FL ingredient in Thailand, extending its use from flavored milk drinks for older children into infant and follow-on formulas, positioning it as a leading Thai provider offering both HMOs and GOS prebiotics.
• EFSA’s six-HMO blend authorization: all new oligosaccharides in the EU undergo the strictest safety-assessment procedure under the Novel Food regulation; for 2025-2026, EFSA approved an expanded blend of six key HMOs (2’-FL, 3-FL, LNT, LNnT, 3’-SL, 6’-SL) for infant and specialized adult nutrition.

05Leading companies and research institutes#

06Tech stack and innovations#

HMO synthesis represents a triumph of metabolic engineering and sophisticated downstream processing:

1. Genetic pathway construction:
   • Fucosylated HMOs (such as 2’-FL) require inserting L-fucosyltransferase genes (typically from Helicobacter pylori or Dictyostelium discoideum) into the host cell (E. coli); sialylated HMOs (3’-SL, 6’-SL) require sialyltransferase genes and optimized CMP-Neu5Ac donor synthesis pathways; blocking degradation requires fully removing the lactose-operon genes (lacZ, lacY, lacA) so the producer strain uses incoming lactose exclusively as an acceptor substrate rather than degrading it.
2. Advanced downstream purification:
   • Bacterial synthesis in E. coli carries endotoxin (cell-wall lipopolysaccharide) contamination risk; achieving food safety requires multiple rounds of nanoporous membrane filtration (under 1 kDa pore size, ultrafiltration) and sorption on specialized activated carbons with controlled pore distribution, guaranteeing complete absence of endotoxins and strain DNA traces.

07Value chains and production pipelines#

Industrial pipeline for precision synthesis of 2’-fucosyllactose (2’-FL)#

┌───────────────────────────┐      ┌───────────────────────────┐
│ 1. Fucose-donor pathway    │ ───> │ 2. Aerobic fermentation on │
│    optimization                 │      │    glucose and lactose          │
└───────────────────────────┘      └───────────────────────────┘
                                                 │
                                                 ▼
┌───────────────────────────┐      ┌───────────────────────────┐
│ 4. Endotoxin sorption &     │ <─── │ 3. Ultrafiltration         │
│    resin desalting              │      │    (biomass separation)         │
└───────────────────────────┘      └───────────────────────────┘
              │
              ▼
┌───────────────────────────┐      ┌───────────────────────────┐
│ 5. Selective crystallization│ ───> │ 6. Spray drying &          │
│    of 2'-FL                     │      │    big-bag packaging            │
└───────────────────────────┘      └───────────────────────────┘

Stage 1: Strain metabolic engineering

An E. coli K-12 strain is constructed with the lactase gene (lacZ) removed and an alpha-1,2-fucosyltransferase gene inserted; expression of GDP-L-fucose synthesis enzymes from fructose-6-phosphate (the de novo pathway) is optimized to build an abundant fucose-donor pool in the cytoplasm.

Stage 2: Aerobic fed-batch fermentation

The process runs in a highly aerated, pressurized fermenter to maximize oxygen supply. Glucose is continuously fed as the energy source; once sufficient biomass concentration is reached, lactose (the acceptor) is introduced into the medium. Bacteria actively transport lactose into the cell, where enzymatic fucose attachment forms 2’-FL, which is exported out of the cell via efflux transporter proteins.

Stage 3: Ultrafiltration (biomass separation)

The culture broth passes through a centrifuge and microfiltration system for complete bacterial cell separation. The resulting clear solution proceeds to an ultrafiltration cascade (5-10 kDa membranes) removing dissolved proteins, enzymes and residual nucleic acid fragments from the producer strain.

Stage 4: Endotoxin sorption and resin desalting

The sugar solution passes through cation- and anion-exchange resin columns for demineralization, then through a bed of granulated activated carbon that selectively adsorbs pigments, byproduct metabolites and trace lipopolysaccharide endotoxins, achieving crystal-clear solution quality.

Stage 5: Selective crystallization of 2’-FL

The purified 2’-FL solution is concentrated in a multi-effect vacuum evaporator to supersaturation; seed crystals are introduced, and controlled cooling crystallizes ultra-pure 2’-fucosyllactose, separating the target product from residual free lactose in the mother liquor.

Stage 6: Spray drying and big-bag packaging

The crystalline mass is redissolved in deionized water and spray-dried under sterile ISO class D conditions. The dried fine-crystal 2’-FL powder, over 98% purity and under 4% moisture, is packed into sealed B2B kraft bags with polyethylene liners for shipment to infant-formula manufacturers.