Human mature milk and colostrum contain 12–13 g/L and 22–24 g/L of milk oligosaccharides respectively, and the structures of least 115 human milk oligosaccharides (HMOs) have been characterized to date. By way of comparison, bovine colostrum collected immediately post partum contains only around 1 g/L of oligosaccharides, and this concentration rapidly decreases after 48 h. It was recently recognized that HMOs have several biological functions, and this study area has become very active, as illustrated by a recent symposium, but it appears that advances in studies on the milk oligosaccharides of domestic farm animals, including cows, have been rather slow compared with those on HMOs. Nevertheless, studies on bovine milk oligosaccharides (BMOs) have progressed recently, especially in regard to structural characterization, with the development of methods termed glycomics. This review is concerned with recent progress in studies on the milk oligosaccharides of domestic farm animals, especially of BMOs and bo...

Quality and Antioxidant Activity of Yogurt Supplemented with Roselle during Cold Storage

The monotreme pattern of egg-incubation followed by extended lactation represents the ancestral mammalian reproductive condition, suggesting that monotreme milk may include saccharides of an ancestral type. Saccharides were characterized from milk of the Tasmanian echidna Tachyglossus aculeatus setosus. Oligosaccharides in pooled milk from late lactation were purified by gel filtration and high-performance liquid chromatography using a porous graphitized carbon column and characterized by ¹H NMR spectroscopy; oligosaccharides in smaller samples from early and mid-lactation were separated by ultra-performance liquid chromatography and characterized by negative electrospray ionization mass spectrometry (ESI-MS) and tandem collision mass spectroscopy (MS/MS) product ion patterns. Eight saccharides were identified by ¹H NMR: lactose, 2′-fucosyllactose, difucosyllactose (DFL), B-tetrasaccharide, B-pentasaccharide, lacto-N-fucopentaose III (LNFP3), 4-O-acetyl-3′-sialyllactose [Neu4,5Ac(α2–3)Gal(β1–4)Glc] and 4-O-acetyl-3′-sialyl-3-fucosyllactose [Neu4,5Ac(α2–3)Gal(β1–4)[Fuc(α1–3)]Glc]. Six of these (all except DFL and LNFP3) were present in early and mid-lactation per ESI-MS, although some at trace levels. Four additional oligosaccharides examined by ESI-MS and MS/MS are proposed to be 3′-sialyllactose [Neu5Ac(α2–3)Gal(β1–4)Glc], di-O-acetyl-3′-sialyllactose [Neu4,5,UAc₃(α2–3)Gal(β1–4)Glc where U = 7, 8 or 9], 4-O-acetyl-3′-sialyllactose sulfate [Neu4,5Ac(α2–3)Gal(β1–4)GlcS, where position of the sulfate (S) is unknown] and an unidentified 800 Da oligosaccharide containing a 4-O-acetyl-3′-sialyllactose core. 4-O-acetyl-3′-sialyllactose was the predominant saccharide at all lactation stages. 4-O-Acetylation is known to protect sialyllactose from bacterial sialidases and may be critical to prevent microbial degradation on the mammary areolae and/or in the hatchling digestive tract so that sialyllactose can be available for enterocyte uptake. The ability to defend against microbial invasion was probably of great functional importance in the early evolution of milk saccharides.