LOUIS FREEDMAN 25 



chloride solution at 60 C. The solution was allowed to cool 

 gradually when the edestin separated as a crystalline preci- 

 pitate. It was purified by redissolving in warm saline solution 

 and again cooling the solution. Apparently, edestin also has 

 great adsorbing properties. Osborne, Wakeman and Ferry 1 r> 

 were unable to free edestin entirely from vitamine. 



Regarding the proteins, the hydrolysates of which showed 

 no growth stimulating activity, a review of their methods of 

 preparation and purification may throw some light on this point. 

 Thus the prolamines, e.g., wheat gliadin, zein and hordein from 

 cereals, were all extracted by means of hot alcohol, the alcoholic 

 solutions evaporated to small volumes and the protein precipi- 

 tated either in water or very dilute salt solutions. As the water 

 soluble vitamines are also soluble in alcohol, we can readily see 

 how all or nearly all of the vitamines would remain in solution. 

 Those proteins, such as the albumins and globulins, which were 

 salted out either by half saturation or complete saturation with 

 ammonium sulphate were all purified by dialysis, and we know 

 that vitamines are dialysable. Thus it is possible that these 

 albumins and globulins have very little adsorbing properties, and 

 therefore can be freed from vitamines by thorough purification. 

 The same apparently holds true for the vegetable globulins with 

 the exception of edestin. 



The glutelins probably were free from vitamines even be- 

 fore extraction with dilute alkali, as they were obtained from 

 the cereal residues after the extraction of the gliadins by means 

 of alcohol. At any rate, the vitamines, if present would prob- 

 ably be destroyed by the continued action of the alkali. 



The active proteins, from published analyses, show nothing 

 in common that cannot be shown to apply to the other, inactive, 

 proteins, so that we can safely rule out the question of amino 

 acids or nitrogen content.* 



* McLeod and Wyon 1T , in a recently published report on the "Supposed importance of 

 vitamines in promoting bacterial growth," used among other extracts, alcoholic extracts of the 

 kidneys of the guinea pig, and they believed that the growth was due to vitamine B, although 

 they stated that the amino acid content of the extracts was also a factor. They also 

 obtained better results with hydrolysed casein than with casein. They also found that 

 "marmite," which is supposedly rich in vitamines, was inactive for the pneumococcus and 

 meningococcus, and that charcoal, devoid of vitamines, when suspended in their bouillon 

 cultures, stimulated the growth of these two organisms. The part of the work of these authors 

 dealing with charcoal and "marmite" will no doubt need confirmation. 



