ROLE OF MANGANESE IN THE BIOLOGICAL SYNTHESIS OF ASCORBIC ACID. THE SYNTHESIS OF INDO-PHENOL REDUCING SUBSTANCES BY GUINEA- PIG LIVER IN VITRO AND IN VIVO

The ability of normal guinea-pig liver to synthesise indophenol-reducing substances In vitro and in vivo in presence of adequate concentrations of manganese has been demons­trated. A hypothesis that the inability of the guinea-pig and the primates to synthesise ascorbic acid within the body is due to insufficiency of manganese, which acts in the capacity of a co-enzyme in the tissues, has been advanced. The probability of synthe­sis of ascorbic acid in human being under certain suitable (generally acid) conditions has been discussed.