Effect of Highly Purified Vitamin B12 Binders from Human Gastric Juice on B12 Absorption in Rats

Abstract
Summary Two highly purified vit. B12-binder fractions prepared as their Co60-B12 complexes from human gastric juice were tested in rats for intrinsic factor activity and other biological properties. The fraction corresponding to the electrophoretically rapid binder showed no IF or inhibitory effect, while the other fraction which has a higher B12 binding capacity exhibited IF activity upon Co60-B12 which was bound to it. The previous failures to demonstrate IF activity with human gastric juice in the rat may be attributed to the former which behaves as a B12 binding impurity.