4 o8 CHEMISTR Y OF THE DIGESTIVE PROCESSES. 



fifteen hours. After filtration the fluid was neutralised, and the neutralisation 

 precipitate separated. This precipitate was digested anew for forty-eight 

 hours with 150 c.c. of strong gastric extract, after which it was re-obtained on 

 neutralisation not sensibly diminished in amount. Dissolved in '75 per cent, 

 sodium carbonate, and mixed with powerful dialysed pancreatic extract, it gave 

 no clot (see " Antialbumid ") when kept for forty-eight hours at 40 C., and 

 neutralisation precipitated only a part, the rest being converted into peptone. 

 This last neutralisation precipitate showed the properties of antialbumid ; 

 dissolved in sodium carbonate solution of 1*8 per cent., it was clear at first, but 

 began to cloud in one to two hours, and in twenty-four hours about half had 

 set into a thick clot which could not be peptonised completely by either peptic 

 or tryptic digestion. The various pancreatic solutions separated from the 

 neutralisation precipitates contained only peptone, and were free from leucine 

 and tyrosine. The antipeptone here obtained contained 30 per cent, of ash. 



Of these three anti-compounds it is only claimed that one, anti- 

 albumose, is a product of natural digestion ; the other two, antialbumid 

 and antialbumate, are admittedly products of acid action or of acid and 

 very weak peptic solution, which amounts to the same thing, and the 

 fact that they cannot be converted into peptones by the prolonged and 

 repeated action of pepsin and hydrochloric acid proves that they are not 

 natural products of strong peptic digestion in which no such inconvertible 

 residue is formed. Antialbumose is commonly stated to be convertible 

 by prolonged peptic digestion into peptone ; but, as may be seen from 

 the above description, it is not materially altered by forty-eight hours' 

 digestion with a strong extract of gastric mucous membrane, and even 

 with trypsin a considerable portion is left unaltered, betraying all the 

 properties of antialbumid. Antialbumose possesses all the chemical 

 properties of an acid albumin and none of those of the albumose class, so 

 that its name is a misnomer ; no such substance as an antialbumose has 

 actually been isolated. Antialbumid, antialbumate, and antialbumose, 

 to place them in the order of their solubility and facility for under- 

 going decomposition, are three substances all of which are remarkably 

 resistant to both peptic and tryptic digestion, and belong more to the class 

 of acid albumins than to any other. It is now generally recognised that 

 acid albumin is a generic and not a specific term, and it is to be hoped 

 that room will soon be found for these three bodies in this class, and the 

 terminology of digestion left a little less complicated than it is at present. 

 It may be asked, Why was antialbumose, if it is not a natural product 

 of peptic digestion, obtained in the above experiment ? The authors 

 themselves remark on the close resemblance between their product 

 and Meissner's parapeptone. The latter is produced either by the action 

 of dilute acid or of a very weak pepsin solution in the presence of acid. 

 Now for two days, while filtering at atmospheric temperature, after the 

 first hour and a half of digestion, the substance was under exactly the 

 proper conditions for the production of parapeptone. Finally, no product 

 so resistant to both pepsin and trypsin, as this substance is shown to be 

 by the above description, is formed during uninterrupted digestion. 



Another method for preparing "antialbumose" Kiihne and Chittenden 1 

 also prepared antialbumose from fibrin by a somewhat similar course of 

 procedure, except that there was here no two days' delay in filtering, since the 

 fibrin was more quickly dissolved. There is, however, an objection no less 

 fatal, as will be pointed out after a description of the process. 



1 LOG. cil. 



