91 



teids. "We have, however, a much smaller amount of nitrogen than is 

 present in most proteids ; but this low content of nitrogen is quite in 

 accord with the constitution of some of the enzymes which have been 



examined. This is shown by the following comparison : 



Nitrogen. 

 Per Cent. 



Bromelin (Chittenden) .. .. 10*46 



Trypsin (Kuhne) .. .. 13-41 



Papaw (Kilmer) .. .. 11-78 



Peptone (Henuinger) .. .. 16*38 



The ferments of Papaw. 



The latex of the papaw is notable from the fact that it contains se- 

 veral soluble enzymes or ferments, or else (if such a thing is possible) 

 a ferment body with a fourfold power. The ferments so far noted as 

 contained in the latex are : 



(1) A proteolytic ferment which decomposes proteids. 



(2) A coagulating (rennet-like) ferment which acts upon the 



casein of milk. 



(3) An amylolytic ferment having the power to attack starch, etc. 



(4) A clotting ferment similar to pectase. 



(5) A ferment possessing feeble powers of action upon fats. 



The digestive action of the latex at the instant of its extraction 

 from the green fruit is very marked. Placed in contact with such a 

 substance as blood fibrin in a little water, the fibrin will be disintre- 

 grated before your eyes , mixed with milk and warmed, the milk is in- 

 stantly coagulated. Boiled starch paste is thinned, and the blue colour 

 produced upon starch by iodine is changed to a purpl^. in a few mi- 

 nutes. Poured over lumps of beef and placed in a warm place, the 

 meat is softened, its fibres disintegrated, finally becoming a partially 

 transparent jelly. The action upon cooked egg albumen is not so 

 marked. 



The latex when dried retains these powers in a somewhat lesser de- 

 gree, lam of the opinion that the ferments exist in the latex, and p -s- 

 sibly in the cellular structure, as a zymogen (carizymogen). This pre- 

 sumption is verified from the fact that after the extraction of the latex 

 or pulp with water (preferably slightly acid or alkaline), a second ma- 

 ceration will bring a further yield of enzyme. I have repeated such a 

 process ten times successively, in each instance bringing a further sup- 

 ply (small in amount) of the ferment into solution. If a considerable 

 bulk of water (neutral, acid or alkaline) be added to the latex, and the 

 resulting liquid be filtered and the residue on the filter paper washed 

 with water, the greater portion of the ferment will be found in the 

 filtrate. 



(To be continued.) 



