κ-Casein from bovine colostrum

Structural characterization of a novel acidic oligosaccharide unit derived from cow colostrum κ‐casein

“…The carbohydrate moiety ofrc-casein obtained from cow colostrum is much more complex than that from cow milk [ 1,5,6]. N-acetylglucosamine (GlcNAc) was found to be a typical, additional constituent of colostrum K-casein.…”

“…Cow colostrum K-caseinoglycopeptide was prepared according to [6] from colostrum obtained 15 min after calving. The caseinoglycopeptide (30 mg) was treated with alkaline borohydride (0.05 M NaOH and 1 .O M NaBH4) for 18 h at 50°C under nitrogen in the dark [ 121.…”

Structural variability of the neutral carbohydrate moiety of cow colostrum κ‐casein as a function of time after parturition

“…The carbohydrate moiety of k--casein during the colostral period is characterized by the presence of N-acetylglucosamine which disappears 66 h after calving [3]. In the present study we investigated neutral oligosaccharide-alditols isolated from cow colostrum and mature milk k--caseins and their structural variations during the colostral period.…”

“…Cow colostrum Ic-caseinoglycopeptide was prepared according to [3] from the colostrum of a unique cow obtained …”

“…(l+3)GalNAc-ol, Gal~(1-+3)[NeuAm(2-+6)]GalNAc-01 and NeuAca(2+3)GalP(I +3)[NeuAca(2-+6)]GalNAc-ol [l, 21. Cow colostrum and cow mature Ic-caseins have the same peptide part; however the colostrum protein has a higher oligosaccharide content [3] with two additional sugars, i. e. N-acetylglucosamine and fucose, and its sugar moieties are much more complex [4, 51. Six different oligosaccharides [6 -91 have already been identified. With the exception of the tetrasaccharide GalP(1 --f 3)[GalP(l-+4)GlcNAcP(1+6)]GalNAc-ol, they contained NeuAc [6 -91.…”