RECENT WORK IN AGRICULTURAL SCIENCE. 



AGRICULTURAL CHEMISTRY— AGROTECHITr. 



A text-book of organic chemistry, E. V. McCk)ixuM {New York: The Mac- 

 millan Co., 1916, pp. XII 1+^26, figs. 25).— la this volume the effort of the 

 author has been to select, for the pui-poses of illustration of a class of com- 

 pounds, such compounds as are of biological importance and interest rather 

 than of technical or synthetical. 



The synthesis of protein substances, P. E. Vekkade {Chcm. Weekbl., H 

 (1917), No. S, pp. S9-10.'f). — This is a general discussion of protein substances, 

 including the synthesis and analysis of the material and of intermediate 

 products. 



The phytic acid of the wheat kernel and some of its salts, P. W. Boutwelx 

 (Jour. Amer. Chem. Soc, S9 {1911), No. 5. pp. ^91-503).— This paper consists of 

 two parts. 



In part I (pp. 491-499), the work on phytic acid is reviewed, and the lack 

 of uniformity in the results of the analysis of the acid and its salts which 

 have been previously publlslied indicatetl. 



Phytin free from inorganic pliosphates has been prepared both from wheat 

 bran and wheat embryo by precipitation from a boiling acetic acid solution. 

 The product obtained was a crystalline calcium-magnesium salt, insoluble in 

 water. It did not agree in composition with any simple calcium-magnesium 

 salt of inosit hexaphosphoric acid, and is indicated as representing a new com- 

 pound from wheat not previously described. The free acid has been separated 

 from this preparation and differs from the .sample previously described in that 

 it is a solid substance readily undergoing spontaneous decomposition during 

 drying in viu'uuni. 



Crystalline barium salts have been prepared from the phytin obtained both 

 from the wheat embryo and the wheat bran by the new procedure. " The 

 barium salt crystallized from the cold dilute hydrochloric solution agrees In 

 composition with an equi-molecular mixture of the trl- and tetra-barium salts 

 of Inosit hexaphosphoric acid. The barium salts crystallized from the dilute 

 hydrochloric acid solution on boiling do not agree in composition with any 

 salts of inosit hexaphosphoric acid, but with a mixed salt consisting of two 

 molecules of tri-barium inosit hexaphosphate and one molecule of tri-barium 

 inosit tetraphosphate." It is indicated that " phytin exists in the wlieat kernel 

 as salts of inosit phosphoric acid, and that phytic acid is an ester of inosit 

 and phosphoric acid." 



II. Concerning the phytase of wheat bran and wheat embrj/o (pp. 499-503). — 

 " In hydrochloric acid of 0.2 per cent concentration the hydrolysis effected by 

 tlie enzym in wheat bran as indicated by the production of Inorganic phos- 

 phoric acid is inhibited, and is only about one-third as great as in the case 

 of 0.1 per cent hydrochloric acid, the concentration of acid in which the enzym 

 exhibits its maximum activity." Dry heat was found to Increase the amount 



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