Structural characterization of oligosaccharides in the milk of an African elephant (Loxodonta africana africana)

The oligosaccharides present in the milk of an African elephant (Loxodonta africana africana), collected 4 days post partum, were separated by size exclusion-, anion exchange- and high-performance liquid chromatography (HPLC) before characterisation by 1H NMR spectroscopy. Neutral and acidic oligosaccharides were identified. Neutral oligosaccharides characterised were isoglobotriose, Gal(β1–4)[Fuc(α1–3)]GlcNAc(β1–3)Gal(β1–4)Glc, Gal(β1–4)[Fuc(α1–3)]GlcNAc(β1–3)Gal(β1–4)[Fuc(α1–3)]GlcNAc(β1–3)Gal(β1–4)Glc, Gal(α1–3)Gal(β1–4)[Fuc(α1–3)]GlcNAc(β1–3)Gal(β1–4)Glc and a novel oligosaccharide that has not been reported in the milk or colostrum of any other mammal: Gal(α1–3)Gal(β1–4)[Fuc(α1–3)]GlcNAc(β1–3)Gal(β1–4)[Fuc(α1–3)]GlcNAc(β1–3)Gal(β1–4)Glc. Acidic oligosaccharides that are also found in the milk of Asian elephant were Neu5Ac(α2–3)Gal(β1–4)Glc, Neu5Ac(α2–6)Gal(β1–4)Glc, Neu5Ac(α2–3)Gal(β1–4)[Fuc(α1–3)]Glc, Neu5Ac(α2–6)Gal(β1–4)GlcNAc(β1–3)Gal(β1–4)Glc, Neu5Ac(α2–3)Gal(β1–4)[Fuc(α1–3)]GlcNAc(β1–3)Gal(β1–4)Glc, Neu5Ac(α2–6)Gal(β1–4)GlcNAc(β1–3)Gal(β1–4)[Fuc(α1–3)]GlcNAc(β1–3)Gal(β1–4)Glc and Neu5Ac(α2–6)Gal(β1–4)GlcNAc(β1–3){Gal(α1–3)Gal(β1–4)[Fuc(α1–3)]GlcNAc(β1–6)}Gal(β1–4)Glc, while Neu5Gc(α2–3)Gal(β1–4)Glc, Neu5Ac(α2–6)Gal(β1–4)GlcNAc(β1–3)Gal(β1–4)[Fuc(α1–3)]Glc, Neu5Ac(α2–6)Gal(β1–4)GlcNAc(β1–3)[Gal(β1–4)GlcNAc(β1–6)]Gal(β1–4)Glc and Neu5Ac(α2–6)Gal(β1–4)GlcNAc(β1–3){Gal(β1–4)[Fuc(α1–3)]GlcNAc(β1–6)}Gal(β1–4)Glc have not been found in Asian elephant milk. The oligosaccharides characterised contained both α(2–3)- and α(2–6)-linked Neu5Ac residues. They also contain only the type II chain, as found in most non-human, eutherian mammals.