Abstract
Hitherto it has been accepted without experimental evidence that in athiaminosis pyruvic acid would occur in human milk, while methyl glyoxal or pyruvaldehyde would never occur in it, especially as this substance has generally been discarded since the Embden-Meyerhof theory came into favor.
But my own actual experiment has shown the following results:
The occurrence of acetaldehyde and methyl glyoxal in human milk was assured by paper chromatography. Pyruvic acid was not identified in human milk. In Parts I and II of this treatise, I stated that I had isolated with success acetaldehyde and methyl glyoxal from human milk. Pyruvic acid was never identified. These results were also ascertained by paper partition chromatography. (Cf. Summary for Parts I & II.)
Remarks. Methyl glyoxal as an intermediate of normal carbohydrate metabolism has, as has been stated in Introduction of Part I, lost in favor. Not only that, but also it has been considered sometimes as secondarily produced or even an “artifact” due to the instability of such substances as glyceraldehyde, dioxyacetone, diacetyl, acetol or lactic aldehyde, from which (esp. the first) the glyoxal might be produced. But now I firmly believe, on the basis of many Reports on Human Milk Study from our Laboratory, that there is an abnormal and quite a natural course of production of methyl glyoxal which, in normal metabolism, will not occur in an identifiable form or, if at all, occur in a trace.
