36 Literatur e on Inosite-Phosphoric Acid [Sept. 



striking are Iwanow's experiments® in which, when yeast was 

 allowed to ferment sugar in the presence of sodium phosphate, there 

 was noted a disappearance of the inorganic phosphorus, amounting 

 to f rom eighty to ninety-three per cent. ; and in the liquors there was 

 foiind an organic phosphorus Compound optically active and giving 

 reactions for aldehydes and ketones. Biochemical syntheses of this 

 class have also been successfully made by other investigators.^*' Of 

 special interest are the inosite esters with ortho- and pyrophos- 

 phoric acid prepared by Anderson. Mention may also be made of the 

 spherocrystals discovered by Hansen" in the parenchyma cells of 

 the Euphorbia caput medusae, which he describes as amorphous 

 masses of calcium and magnesium phosphate, but which Belzug^^ 

 later has shown to be salts of a new organic acid, phosphomalic acid. 

 We may reasonably expect that additional phosphorus-bearing sub- 

 stances of this kind will be discovered in nature by the phyto- 

 chemist for which a rational System of nomenclature will be required. 



Rising, in his paper on inosite-phosphoric acid, refers to soluble 

 phosphorus Compounds obtained from grains, which he promises to 

 discuss in later contributions. These substances he considers closely 

 related to "phytin," and proposes classifying them as a single group 

 with the generic name " phyto-phosphoric acid." This term we may 

 profitably adopt to indicate the acid radicals of those organic phos- 

 phorus Compounds which may be found in the water and dilute acid 

 extracts of plant materials. In this group will be included the gly- 

 cerophosphates, phosphomalates, such hexose and pentose phos- 

 phates as may be discovered in plants, and the phytin-like substances. 



The term " phytin " as used at present seems to designate that 

 substance which is extracted from seeds by leaching with dilute 

 acids, reacting positively in the tests for calcium, magnesium, and, 

 after hydrolysis, for phosphoric acid and inosite. The multiplica- 

 tion of trade names for definite chemical Compounds is not desirable. 

 There are many students and other workers who must of necessity 



'Iwanow: Zeit, für physiol. Chein., 1107, 50, 281-288. 



"Young and Hardin : Biochem. Zeit., 191 1, 32, 173-188; Proc. Chem. Soc, 

 21, 23, 24; Proc. Roy. Soc., London, 77, 80, 81, 82; Euler and Ohlsen: Biochem. 

 Zeit., 191 1, 37, 313. 



" Hansen : Arbeit, des bot. Inst., Würzburg, 1888, 92-122. 



"Beizug: Jour. de bot., 1893, 7, 211-229. 



