580 voegtlin: role of vitamines in nutrition 



modification in the method, in order to obtain the maximum 

 yield. Thus, Dr. Seidell succeeded in removing practically all 

 of the antineuritic vitamine from an active solution of autolyzed 

 yeast filtrate by means of a special preparation of kaolin, or 

 fullers' earth. It was found that the so-called Lloyd's reagent 

 (hydrous aluminium silicate) removes the vitamine from auto- 

 lyzed brewers' yeast. We must assume that this reaction is 

 based on adsorption, a view which will be referred to later. 

 Vedder and Williams had previously shown that animal charcoal 

 will also remove the antineuritic vitamine from an extract of 

 rice polishings. Furthermore, Funk had observed that kaolin 

 removed the antiscorbutic vitamine from cow's milk. We were 

 able to show quite recently that mastic, a resin, also removes 

 the antineuritic vitamine from an autolyzed yeast solution. Dr. 

 Seidell demonstrated that his preparation of vitamine was fairly 

 stable and inasmuch as it is very easily prepared and at low cost 

 this preparation may be expected to be of value in the treatment 

 of certain deficiency diseases. The preparation is being tested 

 clinically at present. The work along this line at the Pellagra 

 Hospital has also yielded encouraging results. Dr. Sullivan and 

 myself have succeeded in modifying Funk's method in such a 

 way as to give a much better yield and a fairly stable preparation. 

 I now shall call your attention to some other results ob- 

 tained by Williams, of the Bureau of Chemistry. Williams 

 prepared some oxypyridines, and on testing these substances on 

 pigeons found that they effected a temporary cure in doses of 

 about 1 mg. This is a most interesting observation. Suzuki 

 and also Funk had previously isolated nicotinic acid from the 

 crude vitamine fraction of rice polishings and yeast. Funk had 

 expressed the opinion that nicotinic acid may be part of the 

 vitamine molecule. It is, therefore, very important that Williams 

 should have discovered the antineuritic properties of some pyri- 

 dine derivatives, especially as nicotinic acid is also a pyridine 

 derivative. This latter substance, however, has no curative 

 action. Whatever may be the final solution of the chemical 

 constitution of this vitamine, whether the synthetic product has 



