needle-shaped crystals was obtained. It gave the reaction of Scherer 

 and melted at 222° C. (uncorrected). After mixing with some previ- 

 ously isolated and analyzed inosite the melting point did not change. 

 The substance was therefore undoubtedly inosite and the analysis was 

 omitted. 



THE HYDROLYSIS OF PHYTIN BY THE ENZYME PHYTASE 

 CONTAINED IN WHEAT BRAN 



It has been shown by the investigations of Suzuki, Yoshimura and 

 Takaishi that rice bran contains an enzyme which rapidly hydrolyzes 

 phytin with formation of inosite and inorganic phosphoric acid. These 

 authors concluded that wheat bran likewise contained a similar enzyme 

 because the inorganic phosphorus increased in wheat bran extracts on 

 standing. 



Plimmer examined a large number of extracts prepared from the 

 intestines, liver, pancreas, castor beans, etc., as to their action on 

 organic phosphorus compounds. While some of these showed a slight 

 cleavage action on phytin, none could be compared in activity to an 

 aqueous extract of wheat bran. The hydrolytic action of these extracts 

 was determined by estimating from time to time the amount of inor- 

 ganic phosphorus split off from phytin solutions of known concen- 

 tration. 



Since the above experiments clearly demonstrated that large quan- 

 tities of inorganic phosphate were liberated from phytin by wheat 

 bran extracts, it appeared of interest to determine what products, in 

 addition to inosite and inorganic phosphoric acid, were formed under 

 these conditions. For this purpose wheat bran extract was allowed to 

 act upon a dilute solution of phytin at a temperature of 37°. Inorganic 

 phosphoric acid was determined in the solution from time to time. 



It was found that about two-thirds of the total phosphorus was 

 split off during the first 16 days. Afterwards there was no apprecrable 

 change even on standing for about two years. 



The solution had been prepared and the original determinations 

 made by Dr. Plimmer. At his suggestion the writer undertook to 

 examine the final reaction mixture for such products as had been 

 formed. 



These products were separated into two portions by precipitating 

 the original solution with barium hydroxide. The precipitate con- 

 tained inorganic barium phosphate, and also those barium salts of 

 organic phosphoric acids that were insoluble in the dilute alkaline 

 solution. The filtrate, on the other hand, was found to contain inosite 

 monophosphoric acid and free inosite. 



The inorganic phosphate and other impurities were removed from 

 the crude barium hydroxide precipitate, as will be described in the 



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