Jan. 14, 1918 Gossypol, the Toxic Substance in Cottonseed 



87 



METHOD OF REMOVING THE TOXIC SUBSTANCE FROM THE ETHER 



EXTRACT 



By treatment of the ether extract of raw kernels with an excess of 

 anUin the gossypol is practically quantitatively precipitated. The 

 dianilin salt produced is extremely insoluble in most solvents except 

 hot anilin and alcoholic potassium hydroxid (KOH). The substance 

 itself is not toxic because of its insolubility. It passes through the 

 alimentary canal unchanged, as can be seen by a glance at the feces. 

 One-half gm. doses of this anilin compound were fed for seven con- 

 secutive days to a rabbit without result, and it was also given to rats 

 in a milk diet (0.3 per cent). The food intake of the rats was not dimin- 

 ished; nor were the rats affected perceptibly 



Gossypol "acetate" was then prepared from this compound as follows: 

 The substance was decomposed by means of an alcoholic alkali. The 

 anilin was steamed off, and the gossypol was extracted with ether and 

 crystallized as the "acetate" by the addition of acetic acid. This was 

 fed in amounts (0.25 per cent) equivalent to the anilin compound (0.3 

 per cent) fed previously. The rats which had not been affected by the 

 anilin compound were promptly affected and consumed but little food 

 (see Table II). 



By passing steam through the extract from which the anilin com- 

 pound had separated the excess anilin was removed, and the resultant 

 oil did not prove toxic to rats. The result of this experiment has led 

 us to believe that gossypol is the only substance in raw cottonseed 

 possessing marked toxic properties. This conclusion was indicated 

 in our previous experiments {17), wherein we found that the gossypol 

 extract freed from gossypol was not toxic. 



Table II. — Results of feeding gossypol "acetate" to rats 



