Measurement of Vitamine Content. 125 



the units etc. are the result of preliminary trials and tests that 

 need not be reported here in detail. Certain questions however 

 arise at once and some of our results to date are presented here as 

 partial answers to these questions pending the accumulation of 

 more complete data. The first question that arises is naturally 

 as to the specificity of the test. Bachman and Williams have gone 

 into this matter somewhat but we believe that our results with the 

 above technique demonstrate additional evidence that this test is 

 specific for the so-called antineuritic vitamine or water-soluble B. 

 Dr. Funk kindly supplied us with a specimen of his purified 

 antineuritic vitamine prepared after his well-known method in 

 1913. A water solution of this material sterilized in the Arnold 

 sterilizer was tested with the results given below. We also made 

 comparative studies of an extract of navy bean made after the 

 McCollum method 4 before and after shaking with Lloyd's 

 reagent. This reagent is supposed to remove quantitatively the 

 B and apparently with little effect upon the other constituents of 

 the extract. The results follow : 



table 1. 



Vitamine Preparation Tested. 



No. Yeast Cells 

 in Unit. 



Incubation 

 Period. 



Cell Count of I 

 Vitamine Tube. 



ncubated Tubes. 

 Control Tube. 



Water sol. Navy bean (a) . 



7-8 



20 hours 



11.237 



113 



Water sol. Navy bean (6) . 



2 



20 



672 



15 



Water sol. Navy bean (c) . 



2 



20 



633 



15 



Same after shaking with 











7-8 



20 



100 



113 



Same after shaking with 











2 



20 



2 



15 



Same after shaking with 













2 



20 



0 



15 



Funk 19 13 preparation . . . 



7-8 



20 hours 



404 



II 





2 



20 



31 



2 





2 



20 



68 



7 



These results seem to demonstrate that what Funk calls the 

 antineuritic vitamine as prepared by him and what we call water- 

 soluble B as prepared by the McCollum method both respond to 

 the test whether they are identical in character or not. The 

 absence of salts and other substances present in the crude navy 



4 McCollum and Simmonds, A study of the dietary essential, water-soluble B. 

 Journ. Biol. Chem. 1918, xxxiii, 55. 



