Differences in oligosaccharide pattern of a sample of polar bear colostrum and mid-lactation milk.

Although the concentrations of carbohydrate in the colostrum and in the mid-lactation milk of polar bear (Ursus maritimus) were similar, the oligosaccharide patterns differed. The colostrum sample contained Neu5Ac(alpha2-3)Gal(beta1-4)Glc (3'-N-acetylneuraminyllactose), GalNAc(alpha1-3)[Fuc(alpha1-2)]Gal(beta1-4)Glc (A-tetrasaccharide), Fuc(alpha1-2)Gal(beta1-4)Glc (2'-fucosyllactose) and Gal(beta1-4)Glc (lactose). The mid-lactation milk contained Gal(alpha1-3)[Fuc(alpha1-2)]Gal(beta1-4)[Fuc(alpha1-3)]Glc (B-pentasaccharide), GalNAc(alpha1-3)[Fuc(alpha1-2)]Gal(beta1-4)[Fuc(alpha1-3)]Glc (A-pentasaccharide), Gal(alpha1-3)[Fuc(alpha1-2)]Gal(beta1-4)Glc (B-tetrasaccharide), A-tetrasaccharide, Gal(alpha1-3)Gal(beta1-4)[Fuc(alpha1-3)]Glc (3-fucosylisoglobotriose), Gal(alpha1-3)Gal(beta1-4)Glc (isoglobotriose) and lactose. The dominant saccharides in the colostrum were 3'-N-Acetylneuraminyllactose and lactose, whereas isoglobotriose was the dominant saccharide in the mid-lactation milk in which lactose was only a minor component. Isoglobotriose, which had previously been found to be a dominant saccharide in mature milk from the Ezo brown bear, the Japanese black bear and the polar bear, was not found in the polar bear colostrum.

Composition and oligosaccharides of a milk sample of the giant panda, Ailuropoda melanoleuca.

A milk sample from a captive giant panda (Ailuropoda melanoleuca), obtained at 13 days postpartum, contained 7.1% protein, 1.6% carbohydrate, 10.4% lipid and 0.9% ash. The ratio of casein to whey proteins was 5.0:2.1. Sodium dodecyl sulfate polyacrylamide electrophoresis (SDS-PAGE) of the whey protein fraction showed the presence of at least two major proteins other than alpha-lactalbumin and beta-lactoglobulin. SDS-PAGE and urea-gel electrophoresis showed that alphas-casein is not a major component. The proportions of triacylglycerol, cholesterol, cholesterol esters and phospholipid were 90.5, 5.3, 0.96 and 3.1%, of the total lipid, respectively. The dominant saccharide in the panda milk was Gal(alpha1-3)Gal(beta1-4)Glc (isoglobotriose). The milk contained, in addition, lesser amounts of lactose, Gal(alpha1-3)Gal(beta1-4)[Fuc(alpha1-3)]Glc (fucosyl isoglobotriose), Neu5Ac(alpha2-3)Gal(beta1-4)Glc (3'-N-acetylneuraminyl-lactose), Neu5Ac(alpha2-6)Gal(beta1-4)Glc (6'-N-acetylneuraminyl-lactose) and Neu5Ac(alpha2-3)Gal(beta1-4)[Fuc(alpha1-3)]Glc.