388 Chemical Constitution of Starch [June-September 



three maitose residues), under the influence of malt extract, first 

 split off these maitose residues as maitose molecules, provided they 

 have been previously provided with hydroxyl groups. For each 

 hydroxyl that the amylogen nucleus takes on, one maitose residue 

 is ready to be split off by the diastase. 



Upon the configuration of the amylogen residues rests the 

 structure of the starch molecule. Synkiewski holds that the amyl- 

 ogen residue contains three different kinds of carbonyl linkings : 

 the one which is readily hydrolyzed by malt, and yields maitose and 

 protodextrin I, is called an a bond; the second, which is broken 

 only by long action of malt diastase and finally yields glucose f rom 

 the protodextrin, is called ß ; and the third, which connects the glu- 

 cose residues in maitose, is called y. According to this scheme the 

 amylogen nucleus may be represented by 



(Ce) -^- (Ce) -y- (Ce) 



ß 



(Ce) -a- (Ce) -y- (C«) 

 ß 



(Ce) -a- (Ce) -y- (C«) 



Since starch consists of n amylogen residues connected by an- 

 hydride carbinol linkings, then, when an a-carbonyl hydrolysis takes 

 place, 3n molecules of maitose are produced and n molecules of the 

 protodextrin I. A j8-carbonyl hydrolysis splits the starch so that 

 each amylogen complex is divided into three similar portions, 

 which can be termed protodextrin-residues IL These residues 

 each consist of three glucose molecules. Since protodextrin II con- 

 tains six glucose molecules, it must consist of two protodextrin- 

 residues II, and its Constitution can be schematically arranged as 

 f ollows : 



(Ce) -y- (Ce) -^- (Ce) - {C,)-a-{C,) —y- (C,) 



From this formula it is apparent that the molecule of this sub- 

 stance contains two intact y bonds and two maitose groups con- 



