426 Journal of Agricultural Research voi. iii, No. s 



phoric esters of inoske, stand in the way of obtaining the pure substance. 

 Special attention was paid to methods for the determination of the 

 barium and phosphoric acid in the salt, and observations of some interest 

 were made. 



The total phosphorus was determined in samples of rice bran and 

 unpoUshed and polished rice. The following determinations were dupH- 

 cated to within 0.02 per cent: Phosphorus in rice bran, 2.291 per cent; 

 in unpolished rice, 0.321 per cent; in polished rice, 0.140 per cent. 



It is apparent that the rice bran contains a comparatively high per- 

 centage of phosphorus. Phytin was determined in the bran by extracting 

 100 gm. of the sample with a 0.2 percent hydrochloric-acid solution and 

 precipitating with alcohol. The precipitate stood over night, when it 

 was filtered, first washed with 50 per cent alcohol, then with ether, and 

 was dried at 105° C. It weighed 8.22 gm., amounting, therefore, to 

 8.22 per cent of the bran. As phytin contains considerable organic phos- 

 phorus, it is apparent that rice bran contains much of its phosphorus in 

 the organic form. 



The writer was unable to obtain phytin from the polished rice. The 

 0.2 per cent hvdrochloric-acid extract from several kilograms of finely 

 ground pohshed rice yielded but a slight precipitate with alcohol or barium 

 chlorid. With barium hydroxid added to alkalinity a considerable pre- 

 cipitate occurred which did not behave like phytin. 



The phytin obtained from the unpolished rice was doubtless contained 

 in the outer layer, which is removed in polishing. 



Two i)reparations of barium phytate were made according to the 

 method of Anderson; one from unpolished rice, the other from rice bran. 



Six kg. of finely ground unpolished rice were treated with a 0.2 per 

 cent hydrochloric-acid solution for several hours. This was filtered 

 through cheesecloth and filter paper the same day and the filtrate pre- 

 cipitated with a barium-chlorid solution. 



The precipitate was collected on a filter, washed with 50 per cent alco- 

 hol, dissolved in a i.o per cent hydrochloric-acid solution, which was 

 then filtered and precipitated with barium hydroxid. It was reprecipi- 

 tated three additional times with barium hydroxid, once with alcohol, 

 again with barium hydroxid, and again three times with alcohol. The 

 filtrate from the alcohol precipitate soon ceased to give an immediate 

 precipitate with an ammonium-molybdic solution, showing the elimi- 

 nation of inorganic phosphoric acid from the precipitate. The precipi- 

 tates formed by barium hydroxid were well washed with water. 



Crystals were then obtained by adding barium hydroxid to the acid 

 solution until a slight precipitate resulted and then filtering and allowing 

 to stand a couple of days. The crystals thus formed were washed, recrys- 

 tallized in the same way, and then crystallized from the acid solution by 

 the addition of alcohol. It was found that on adding an equal volume 

 of alcohol, according to Anderson, only an amorphous precipitate was 

 obtained. It was only by adding just sufficient alcohol to make the 

 solution turbid that crystallization took place. 



Under the microscope the precipitate appeared to be composed entirely 

 of crystals in the form of globules of needles with occasional needle- 

 shaped crystals arranged in stellar form. These were probably the 

 same substance. 



The crystals were washed with alcohol and ether, dried in vacuum over 

 sulphuric acid at laboratory temperature, and finally at 105° to 110° C. 



