THE EFFECT OF POTASSIUM BROMATE UPON 
ENZYME ACTION. 
By I. S. FALK anp C.-E. A. WINSLOW. 
(From the Department of Public Health, Yale School of Medicine, New Haven.) 
(Received for publication, November 14, 1917.) 
One of the most recent important advances in the practical 
art of breadmaking has been the introduction into the dough of a 
mixture of mineral nutrients known as Arkady Yeast Food.! 
This material, which was devised in the laboratories of the Mellon 
Institute of Pittsburg, includes salts of calcium and ammonium 
and a minute amount (1 part in 200,000) of potassium bromate. 
The functions of calcium and ammonium as yeast foods are 
fairly well understood; but the reasons for the favorable action 
of the bromate remained somewhat obscure. It seemed possible 
that this salt might exert a specific stimulating action upon the 
proteolytic enzymes active in the fermentation. It had been 
shown by Chittenden and his associates? that bromides in certain 
dilutions had a marked accelerating effect on the action of ptyalin, 
pepsin, and pancreatin. Wohlgemuth? noted the same effect 
on ptyalin and pancreatin. More recently Thomas‘ reports a 
strongly stimulating influence of bromides upon amylase; and 
Robertson® in an exhaustive study of the action of trypsin on 
casein notes a stimulating action of potassium bromide. On the 
other hand, Senter,® and Battelli and Stern,’ and Jappelli® found 
1 Allen, R. M., Baker’s Weekly, 1916, xviii, 31. 
2 Chittenden, R. H., and Painter, H. M., Tr. Conn. Acad. Aris and Sc., 
1885-88, vii, 60. Chittenden, R. H., and Allen, S.E., zbid., 84. Chitten- 
den, R.H., and Cummins, G. W., zbid., 108. - 
3 Wohlgemuth, J., Biochem. Z., 1908, ix, 10. 
4Thomas, A. M., J. Am. Chem. Soc., 1917, xxxix, 1501. 
> Robertson, T. B., J. Biol. Chem., 1906-07, 11, 317. 
6 Senter, G., Z. phystkal. Chem., 1903, xliv, 257. 
7 Battelli; F., and Stern, L., Arch. internat. Physiol., 1907, iv, 465. 
8 Jappelli, A., Atti XXII cong. med. int. Roma, 19138, 405. 
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