CHAP. II.] 



AXTIALBUMAT AND ANTIALBUMID. 



121 



containing casein. When the" jelly is subjected to long-continued 

 digestion wih trypsin, it is in part gradually dissolved, and the solu- 

 tion is found to contain aritrpeptbne, as well as some unchanged 

 antialbumid, but no trace of leucin or ty rosin. 



Whilst the action of acids gives rise, in the way described, to those 

 special products of decomposition belonging to the anti-group, 

 which are denominated antialbumat or antialbumid, there are also, 

 necessarily, separated at the same time bodies of the hemi-group, 

 and ultimately these are resolved, according to circumstances (nature 

 and strength of acid, temperature and- duration of process of 

 heating) into hemipeptones or into the amido-acids which result from 

 decomposition of the latter. The production, as well as the facts con- 

 nected with the formation, of the bodies of the hemi-group, as well 

 as the formation and properties of antipeptone are most suitably 

 discussed in connection with the action of the enzymes on proteids. 

 Before treating this branch of the subject, the schemata which Kiihne 

 has furnished exhibiting the decomposition of proteids under the 

 influence of acids are placed before the reader. 



Schema of Proteid Decomposition by Acids, 

 a. Action of dilute HC1 (0*25 per cent.) at 40 C. 



Proteid 

 Antialbumat 



Antialbumid 



Hemialbumose 



i 



Hemipeptone 



6. Action of dilute H 2 S0 4 (35 per cent.) at 100 C. 



Proteid 



Antialbumid Hemi-albumose 



Hemipeptone Hemipeptone 

 Leucin Tyrosin Leucin Tyrosin 



The Albumoses. 



Albumoses 

 and peptones 



the* actton^of 



We have seen that under the influence of heat, 

 dilute solutions of the mineral acids are able to effect 

 the decomposition of the proteid molecule, giving rise 

 pepsin and after long-continued action to certain quantities of 

 acids on pro- bodies of the anti-group which resist the further de- 

 composing action of the acids, as well as to products 

 derived from the hemi-moiety of the proteid molecule. 



The decomposition, which acids effect with comparative slowness, 

 proceeds with infinitely greater rapidity in the presence of pepsin and 



