A RESUME OF THE LITERATURE ON INOSITE- 



PHOSPHORIC ACID, WITH SPECIAL REFER- 



ENCE TO THE RELATION OF THAT 



SUBSTANCE TO PLANTS 



ANTON RICHARD ROSE 



(Laboratory of Biological Chemistry of Columbia University, at the College of 

 Physicians and Surgeons, New York) 



Contents. — Discovery: by the microscopist, 21; by the chemist, 22. Occur- 

 rence, 2^; preparation, 25; properties, 26; Constitution, 31; terminology and Clas- 

 sification, 35 ; analytical methods, 37 ; role in plants, 39. Bibliography, 46. 



DISCOVERY OF INOSITE-PHOSPHORIC ACID SALTS 

 BY THE MICROSCOPIST 



In 1854 Hartig/ engaged in a microscopic study of the seeds o£ 

 various plants, noted in all his sections small particles similar to the 

 starch grains of the potato, which at that time were absorbing the 

 interest of plant physiologists.^ These grains were obviously not 

 starch, as they did not give the characteristic blue color with iodine 

 in potassium iodid Solution. They are more commonly present in 

 seeds than starch, the latter being frequently replaced by fat. 

 Hartig considered them an essential reserve product designed to 

 play an important part in the germination of the seed and the 

 growth of the plant. He first called them " Klebermehl " but 

 within a year renamed them " aleurone grains " f rom the Greek 

 aXevpov (wheat fiour), a term still in use. Not only did he consider 

 them significant for the plants in which they are found but also for 

 the animals which eat them. The method which he employed for 

 separating them from the other parts of the seed is the one usually 

 followed by the investigators who have since worked with these 



^ The papers ref erred to in the text and not accompanied by f ootnote ref er- 

 ences are those which pertain specially to the literature of inosite-phosphoric 

 acid and are given at the end of this review in the alphabetical order of the 

 names of the authors. 



^The starch grains were minutely studied by Nägeli and his coworkers. 

 Their work (collected in Die Stärkekörner, 1858) probably afforded the Stimulus 

 for the efforts which led to the discovery of inosite-phosphoric acid so early. 



21 



