THE ORGANIC PHOSPHORIC ACID OF COTTON- 

 SEED MEAL.* 



R. J. ANDERSON. 



SUMMARY. 



Cottonseed meal contains an organic phosphoric acid which is 

 very similar to phytic acid. When heated in a sealed tube with 

 dilute sulphuric acid it decomposes into inosite and phosphoric 

 acid. Whether the substance is identical with ph3rtin could not 

 be determined. The acid gives easily crystalUzing barium salts. 



The aqueous solution of the free acid gives all those reactions 

 which have been attributed previously to the presence of pyro- and 

 metaphosphoric acids in cottonseed meal. 



The acid when given in 0.5 and i gram doses to rabbits does not 

 show any marked toxic properties. Symptoms of distress were 

 produced but the animals recovered their normal appearance after 

 two or three hours. 



INTRODUCTION. 



In the investigation of the organic phosphoric acids present in 

 various cereals and feeding stuffs which is being carried out in this 

 laboratory, cottonseed meal was also examined. Earlier work by 

 other investigators has shown that this product probably contains 

 some complex organic phosphoric acid.^ It seems, however, that 

 if such a substance is present it has not been isolated in pure form 

 nor have its properties been fully studied. 



The opinion seems to be generally held that cottonseed meal 

 contains some poisonous principle, but the exact nature of this 

 principle has never been definitely determined. It has been claimed 

 that pyro- and metaphosphoric acids were present in cottonseed 

 meal" and it was thought that the poisonous properties of the pro- 

 duct were due to the presence of salts of these acids. More recent 

 work by Crawford^ led him to believe that the poisonous principle 

 was a salt of either a simple inorganic or a complex organic pyro- 

 phosphoric acid. 



The presence of these acids has been adduced from the fact that 

 the extracts of cottonseed meal give reactions similar to those of 

 the above acids, viz., anomalous behavior towards ammonium 

 molybdate, white precipitates with silver nitrate and coagulation of 

 egg albumen; further, the poisonous effects resemble those given 

 by these acids. Aside from these reactions, however, there is no 



1 Rather, Texas Agr. Exp. Sta. Bull. 146 (1912) ; see p. 176 of this Report. 

 - Hardin, So. Carolina Agr. Exp. Sta. Bull. 8, New Series (1892). 

 'Crawford, Jour. Pharni. and Exper. Ther. I: 519 (1910). 

 * A reprint of Technical Bulletin No. 25, December, 1912. 



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