303 
ON PEP SINE. 
BY FRANK VINCER. 
Pepsine was introduced into medicine by Dr. Lucien Corvisart. The 
daily increasing importance of pepsine, which has now been in use 
during the last fourteen years, demands a short history— 1. 01 its 
extraction ; 2. Its employ ; 3. Its pharmaceutical preparations, including 
the principle formulae in use. 
1. This substance, which is the active principle of the gastric juiee, 
is found in those glands of the stomach called peptic of vertebrate 
animals ; but the isolation and preparation, so as to preserve to this 
agent its physiological properties, are extremely delicate operations. 
A. Certain pharmaciens have lately found no means more profitable 
and economic than that of simply drying the mucous membrance of the 
stomach of animals (pigs, &c), and selling it under the name of pepsine. 
Nothing is more simple, but nothing more deplorable in every respect ; 
the name of this product is at once a falsification, as the pepsine is as 
impure as it is possible for it to be, none of the detritus of the dead 
membrane or of the putrid matter being removed. For example, if this 
powder is mixed with water and maintained for twenty-four hours at a 
temperature of 40° C, it is decomposed, and exhales an insupportable 
and fetid odour. This in Germany has been designated " Pepsine de 
Lamatch." These products are easily recognized under the microscope, 
which discloses the organic cellular debris. 
B. Other manufacturers have at least eliminated those putrefiable 
portions of the gastric membrane which are solid. Heidenham directs 
the maceration of frogs' stomachs and the liquid portion only is desic- 
cated. Some, to disguise the putrid matter (after the example of Dr. 
Aschentreumer), have added to this product, before evaporation, 2 to 5 
per cent, of salt. The preparation sold at Berlin under the name of 
u Pepsine de Simon " contains salt ; this is easily recognized, as, when 
exposed to the air, it becomes viscid and attracts moisture rapidly, an 
inconvenience which causes the weight of the pepsine to vary with the 
closing of the bottles and the changes of the atmosphere. 
These preparations are simply the liquid or solid rennet, in which, 
at the end of a few days, the digestive property is lost ; that of 
Aschentreumer has been named Chymosum Muriaticum dilutum. None 
of these can be called pepsine, and ought to be studiously interdicted, 
as they are merely falsifications. 
We will now consider pepsine isolated from all foreign matters—that 
is to say, chemically pure. Schwann was the first (1834) who extracted 
(and named) pepsine from the gastric juice in a state of purity ; to this 
end he made use of bichloride of mercury, which precipitates pepsine ; 
the precipitate was dissolved in hydrochloric acid, through which he 
then passed a current of sulphuretted hydrogen to throw down any 
excess of mercury, and leave the pepsine in solution. Wasman employed 
