90 OTTO GLASER. 



however, is not associated with the egg pigment or the aggluti- 

 nating material, but with the lipolysin, whose concentration in the 

 cortex is thus one step nearer to being a demonstrated fact. 



VIII. Copper and Enzymes. 



Lipolysin is or contains a lipolytic ferment whose presence ac- 

 celerates the hydrolysis of higher and lower fats ('22 2 ) and the 

 synthesis of ethyl-butyrate ('22 3 ). The association of copper with 

 this enzyme, though contrary to expectation, can not be evaded. 

 Does the case stand alone? 



Apparently not. For example, S. Yagi ('io 2 ) finds a thirty-four 

 fold increase in the copper content of the rabbit's liver when the 

 animal is fed 4.8 gr. copper sulphate in assimilable doses during a 

 period of seventeen days. This agrees perfectly with the results 

 of Titze and Wedemann ('n) on the goat and those of Rose and 

 Bodansky ('20 1 ), who find the copper content of the oyster's 

 hepato-pancreas to be twice that of the muscle. Although as yet 

 no one has risked the suggestion, it seems apparent that copper 

 concentrates in tissues rich in lipases and certain other enzymes. 

 May we risk another step and say the copper is concentrated in the 

 enzymes? Be this as it may, it was these considerations that led 

 me to test the following commercial preparations : 



A. Pancreatin (Merck's). 



This preparation contained all the pancreatic enzymes. The ash 

 from about .2 gr. gave a marked reaction for copper as copper xanthate. 



B. Pancreatin from Pig (Squibb's). 



Result exactly as in A. 



C. Pancreatin (Parke-Davis). 



Result as in B and A. 



Is the copper associated with the lipases exclusively ? This can 

 not be determined from the above tests. I therefore tried a 

 proteolytic enzyme likely to be free from lipases, amylases, and 

 other enzymes. 



D. Pepsin (origin unknown). 



The ash from .2 gr. when freed from iron gave no positive indication 

 for copper. However, the iron hydroxide was found to hold the cop- 

 per back. I therefore washed the precipitated hydroxide with ammo- 



