ENDOTRYPTASE. 



55* 



is concerned, this latter observation is also of practical importance 

 to the fermentation process. 



Weak antiseptics (chloroform, thymol, toluol, 0.2 per cent, 

 salicylic acid, o.i per cent, formaldehyde) do not appear to have 

 any influence on the action of endotryptase. On the other hand, 

 powerful precipitants (3 per cent, phenol, o.i per cent, sublimate) 

 naturally stop the digestion, which, however, contrary to the 

 statements of Schar with regard to enzymatic action, is not 

 restricted by i per cent, hydrocyanic acid. Even in concentrated 

 solutions up to 5 per cent., according so T. GROMOW (I.), of 

 neutral salts, such as sodium, potassium and calcium chloride, 

 stimulate proteolysis, whilst saturated solutions have a powerfully 

 restrictive influence. Additions of 50 per cent, glycerine and 

 saccharose also retard proteolysis considerably, and therefore 

 preserve the alcoholase (see p. 477, vol. ii.),as well as the proteids. 

 These discoveries of Geret and Halm were supplemented by the 

 observation of T. GROMOW (I.), to the effect that, not only glycerine 

 and saccharose, but also mannitol, glucose, lactose, and glycocoll 

 restrict the proteolysis of permanent yeast suspended in water. 

 In the case of saccharose, this effect is already apparent on the 

 addition of 5 per cent., whilst the proteolysis almost entirely ceases 

 in presence of 35 per cent. Saccharose has a more powerfully 



