114 Some Protein Compounds [Sept. 



react to form a water-soliible protein Compound which, in aqneous 

 Solution, yields mucoid on treatment with 0.2 per cent. hydrochloric 

 acid. The morphin enters into combination in a proportion so small 

 as to be incapable of responding to the iodic test, or is united in 

 such a way as to fail to respond to the test. 



B. Strychnin mucoid. In view of the extreme delicacy of 

 the dichromate test for strychnin, this base was selected for the 

 second series of preparations. Care was taken to insure purity of 

 the original materials as in the preparation of the morphin-mucoid 

 products. 



Preparation. The method of preparation was identical with 

 that for morphin mucoid (page 112) except in the following details: 

 The final water-solution of the product was again evaporated to dry- 

 ness at 40° C. and the dry matter, after pulverization, was extracted 

 with Chloroform. Twenty-six voluminous washings were neces- 

 sary to free the powder from admixed strychnin and to obtain a 

 strychnin-free washing. In view of the insolubility of strychnin 

 in water and its ready solubility in ether this result seemed difficult 

 to explain on any other basis than partial dissociation by the 

 Chloroform. 



Evidence of chemical combination. The protein character of 

 the Compound was established by the following results : The water- 

 solution gave a strong biuret test; was precipitable by Saturation 

 with ammonium sulfate or magnesium sulfate; gave a flocculent 

 precipitate with 0.2 per cent. hydrochloric acid and 4 per cent. acetic 

 acid Solutions ; and f rothed strongly on shaking. The aqueous Solu- 

 tion of the product was neutral to litmus. 



The presence of strychnin was shown by the intense bitter taste 

 and by strong "dichromate tests." Filtrates from precipitates 

 formed by addition of 0.2 per cent. hydrochloric acid Solution 

 yielded, in every case, strong "di-chromate tests " for strychnin. 

 Four physiological tests were also made to establish the presence 

 of the strychnin. The results and methods follow : 



The lethal dose of strychnin sulfate is about 2.5 mg. per kilo of 

 weight for frogs and 7.6 mg. per kilo of weight for dogs. Vol- 

 umes of aqueous Solution of strychnin mucoid (0.575 ^S- P^^* ^■^•) 

 containing quantities equal to the lethal dose of strychnin sulfate 

 were injected subcutaneously in frogs and dogs. 



