Feb. 9,1924 
The Association of Manganese with Vitamins 
421 
ganese agree very closely with the findings of other investigators in show¬ 
ing that the liver, kidney, heart, brain, and pancreas are richer in vitamin 
content than other parts of the animal body, thus indicating a close par¬ 
allelism between vitamin and manganese content in the parts of the 
animals examined. Undoubtedly manganese has a very important func¬ 
tion to perform in the liver, kidneys, and pancreas. Since twice as much 
manganese was found in the liver as in any other part of the body, it is 
logical to assume that this accounts for the fact that the liver is also a rich 
source of vitamins. Several investigators report that they have found 
the liver of different animals a cure or preventive of the common diseases 
resulting from the lack of an adequate supply of vitamins. 
MANGANESE IN THE LIVER OF CODFISH 
Investigators have found that the liver of codfish is rich in fat-soluble 
A vitamin, and many efforts have been made to isolate this vitamin 
from cod-liver oil, but without success. According to Plimmer (9), fat- 
soluble A is synthesized in the green parts of plants, and the white leaves 
of cabbage contain less A factor than the green leaves. Lower plants 
(marine algae) containing chlorophyll synthesize this vitamin. The ma¬ 
rine algae are eaten by small marine animals, which in turn are eaten by 
larger ones, eventually by codfish. The fat-soluble A factor in the cod¬ 
fish is chiefly concentrated in its liver. 
In view of the fact that manganese was found in greater concentration 
in the livers of the hog, sheep, and cow than in other organs, it is reason¬ 
able to expect the liver of the codfish to contain a larger proportion of 
manganese than any other part of its body. A sample of cod-liver chum, 
the disintegrated cod-liver tissue after the steaming process, and also some 
of the clear supernatant cod-liver oil, were obtained from codfish caught 
near Portland, Me., on May 12, 1923, and each of these materials was ex¬ 
amined for manganese. The cod-liver chum was dried at no° C. and 
manganese determined in 100 gm. of the moisture-free material. The 
dry chum contained some oil. Pour parts per million of manganese 
were found in the dry chum, from which it is apparent that the liver of the 
codfish does contain a considerable quantity of manganese. Two hun¬ 
dred grams of the clear, golden-colored cod-liver oil was burned by means 
of a wick in a platinum dish and the residue tested for manganese. 
Only a trace was found. 
Another sample of what was claimed to be a high grade of purified Nor¬ 
wegian cod-liver oil which, according to the statement on the label was 
rich in fat-soluble A vitamin, was examined in a similar way for manga¬ 
nese and approximately one-tenth part per million of manganese was 
found. The manufacturer from whom the sample was obtained states 
that the potency of cod-liver oil as a source of fat-soluble A varies with the 
source of the oil and the treatment it has undergone in the process of re¬ 
fining. It is stated that cod-liver oil that has been subjected to super¬ 
heated steam or has been highly refined by filtration loses itfe potency as a 
source of fat-soluble A factor. 
Funk (3) states that he has found the crude cod-liver oil to be richer 
in fat-soluble A vitamin than the refined oil. He also states that Zilva 
and Miura ( 12 ), in their experiments with animals, found the crude 
cod-liver oil to have a fat-soluble A potency 250 times greater than 
butter fat. However, since it has been shown that the liver of the cod¬ 
fish is the richest source of the fat-soluble A vitamin and that the unre- 
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