THE ASSOCIATION OF MANGANESE WITH VITAMINS 1 
By J. S. McHargue 
Research Chemist , Department of Chemistry , Kentucky Agricultural Experiment Station 
In a former paper (7) 2 data were presented to show that manganese is 
an essential element in the growth and normal development of auto¬ 
trophic plants and functions in the synthesis of chlorophyll. The pur¬ 
pose of this paper is to present data which further confirm previous con¬ 
clusions as to the essential character of manganese as a vital factor in 
life processes, to suggest a new theory concerning the nature of the 
vitamin factors, and to present data in support of that theory. 
The observations of Takaki and the experiments of Eijkman, as quoted 
by Sherman and Smith (it, p. 8-g), show conclusively that the pericarp 
and germ of rice and barley grains contain a vital factor which prevents 
the development of beriberi in animals when the brown unpolished 
grains are consumed in the diet. 
As early as 1854 Liebig (4) called attention to the fact that in the 
modern process of milling wheat the resulting flour contains less nutritive 
value than flour made from the whole grain. He states that “No.single 
foodstuff loses its value so readily as whole grain through the modern 
process of milling. The whiter the flour the less nutritive value it 
possesses.’* These statements have been confirmed in many ways since 
the time of Liebig, and it is apparent that the pericarp and germ of 
wheat, barley, and rice each contains some unidentified vital factor 
which is necessary for the normal metabolic processes and physiological 
well-being in animal life. 
Physiologists and biochemists everywhere are strenuously endeavoring 
to ascertain the function of each of the known chemical constituents of 
food. Since manganese is a known constituent of foods, the question 
arises as to whether or not this element has important functions in the 
metabolic processes of animal life which have been overlooked in previous 
investigations. 
In 1914 the writer (5) published a paper in the Journal of the American 
Chemical Society, entitled “The Occurrence and Significance of Manga¬ 
nese in the Seed Coat of Various Seeds.” In this paper it was shown 
that the pericarp of wheat and of a considerable number of other seeds 
contains much more manganese than the starchy and glutinous portions 
of the endosperm. It was suggested at the conclusion of the article 
that probably the manganese contained in the pericarp of different 
seeds performs an important function in the growth of plants. While 
this suggestion was somewhat prophetic at the time, the author has since 
obtained conclusive evidence that manganese does play the part of an 
essential element in plant growth. This fact is evidenced in data previ¬ 
ously published (< 5 , 7) and is further confirmed by the accompanying 
photograph of tomato plants (PI. 1), the fruit of which is assumed to 
contain an important vitamin factor. 
1 Accepted for publication Nov. 19, 1923. Contribution from the Laboratory of Chemical Research of 
the Kentucky Agricultural Experiment Station. Published with permission of the Director. 
8 Reference is made by number (italic) to “Literature cited,” p. 424. 
Journal of Agricultural Research, 
Washington, D. C. 
(417) 
Vol. XXVII. No. 6 
Feb. 9. 1924 
Key No. Ky.-is 
