A CONTRIBUTION TO THE CHEMISTRY 



OF PHYTIN.* 



SUMMARY. 



R. J. ANDERSON. 



This bulletin contains the report of an investigation concerning 

 the composition of the organic phosphoric acids of cottonseed meal, 

 oats and corn in comparison with commercial phytin. 



It is shown that from all of these substances identical barium 

 salts are obtained which agree very closely in composition with the 

 following types of salts, viz: 



Tribarium inosite hexaphosphate, CeH^C^PeBaa, obtained as 

 minute bundles or globules of microscopic needles from dilute 

 hydrochloric acid solutions by the addition of alcohol, and hepta- 

 barium inosite hexaphosphate (CeHnO^Pe^BaT, or Ci 2 H22048Pi2Ba 7 

 which separates from dilute hydrochloric acid solutions in the 

 presence of barium chloride in globular masses of needle-shaped 

 crystals. 



The free acid prepared from the crystalline barium salts agrees 

 more closely in composition with inosite hexaphosphate, C 6 Hi 8 2 4P6» 

 than with the usual formula for phytic acid, C6H24O27P6. 



Oats apparently contains two different organic phosphoric acids 

 but only one, that corresponding to inosite hexaphosphate, has 

 been isolated in pure form. 



The spontaneous decomposition products of phytic acid unaer 

 ordinary conditions which are formed within a reasonable length of 

 time appear to be phosphoric acid and substances which contain 

 more carbon and less phosphorus than phytic acid, which sub- 

 stances are probably penta-, tetra-, etc., phosphoric acid esters of 

 inosite. 



When phytic acid is dried at a temperature of 105 under reduced 

 pressure, it rapidly decomposes with liberation of inorganic phos- 

 phoric acid and the formation of various decomposition products, 

 consisting of inosite and substances varying in composition from 

 inosite tetraphosphate to inosite monophosphate. 



When the crystalline barium salts are dried at 105 under reduced 

 pressure they suffer but slight hydrolysis. Under ordinary con- 

 ditions the dry salts are comparatively stable but on longer keeping 

 small quantities of inorganic phosphoric acid are liberated. 



* Reprint of Technical Bulletin No. 32, January. 



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