Possible influence of vitamin B12-binding protein in milk on the intestinal flora in breast-fed infants. I. B12-binding proteins in human and bovine milk
Gullberg, R.
Scandinavian Journal of Gastroenterology 8(6): 497-503
1973
ISSN/ISBN: 0036-5521 PMID: 4797858 Document Number: 68988
Human milk was found to contain relatively large amounts of an unsaturated vitamin B12-binding protein with the same elution properties as the large mol. size vitamin B12-binder found in other body fluids. Virtually no unsaturated vitamin B12-binding protein could be demonstrated in any of the tested cows' milk or commercial milk products used in infant feeding. Average unsaturated vitamin B12-binding capacity of human milk samples heated to 56, 62 and 73 deg C respectively was (ng/ml) 153.95, 14.15 and 30.68. Fresh milk from only 1 of 5 cows contained unsaturated vitamin B12-binding protein with a binding capacity of 2.95 ng/ml after heating the samples to 56 deg C; heating to 62 or 73 deg C caused no significant change. It is suggested that the vitamin B12-binding protein in human milk contributes to the milk's protective effect against gastrointestinal infections in infants.o.