The effect of acid peptic digestion on free and tissue-bound cobalamins

Abstract

1. The extent of liberation of radioactive cobalamin in rabbit tissues incubated with acid and pepsin was evaluated by bag dialysis. 2. Between a half and two-thirds of the cobalamin—probably hydroxocobalamin—was dialysable after acid pepsin treatment and this process may be a factor in the absorption of cobalamins from foods. 3. Studies of pure cobalamin solutions at different concentrations gave apparently anomalous results, which may have been due to the adherence of cobalamin to the dialysis membrane. Measurement of the amount adherent to the membrane is an important factor in dialysis studies with cobalamins.