CHEMICAL PHENOMENA IN LIFE 



Then amylases have been met with which did 

 not show this guaiacum reaction. Finally extracts 

 were obtained from plants which only gave the 

 guaiacum reaction but did not act upon starch. 

 So the conviction was arrived at that the blue 

 reaction with guaiacum and the starch-decom- 

 posing effect belong to different enzymes, which, 

 it is true, very often occur together. 



Since we know very little about enzymes, 

 except of their action, it is natural to found the 

 system of the enzymes upon the kind of reaction 

 which each carries out. Thus the nomenclature of 

 enzymes nowadays is generally taken from the 

 enzyme action. It was found convenient to 

 compose the name of the enzyme with the ending 

 -ase, taken from the first described and isolated 

 enzyme, the Diastase. As the root of the name 

 of an enzyme, is taken the name of the substance 

 which is decomposed by this enzyme. So we 

 shall call starch - decomposing enzymes, from 

 amylum, starch, Amylase ; similarly the enzyme 

 acting on cane sugar Saccharase, etc. 



The chemical characteristic of the enzyme 

 reaction or the special decomposition caused by 

 the enzyme is very different. In many cases the 

 action consists, as in cane-sugar inversion or 

 starch dissolution, merely in an addition of water, 

 which is followed by a splitting up of the substance. 

 Chemists generally call such effects Hydrolysis^. 

 All enzymes which provoke hydrolysis may be 



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