GOSSYPOL. THE TOXIC SUBSTANCE IN COTTONSEED 



By W. A. Withers and Frank E. Carruth, 



Chemical Division, North Carolina Agricultural Experiment Station 



REVIEW OF PREVIOUS WORK 



Since our previous publication (77)^ on this subject, several articles 

 have appeared in which other explanations of cottonseed-meal poison- 

 ing have been offered. 



Thus, Rommel and Vedder (14) have suggested that poisoning by 

 cottonseed meal is similar to beriberi, and is caused by deficient diets. 

 This view was based on the similarity of post-mortem symptoms noted 

 in pigs fed on rice and tankage. 



Wells and Ewing (15) have concluded that cottonseed-meal injury is 

 due in large part to incomplete diets. 



Richardson and Green (11) fed white rats and concluded that cotton- 

 seed meal and flour are not actively toxic, but contain insufficient 

 minerals and possibly inadequate amounts of the fat-soluble growth- 

 promoting substance. 



Osborne and Mendel (10) have secured results similar to those of the 

 last-named authors with cottonseed meal and flour, but on subsequently 

 feeding raw cottonseed kernels supplied by us, they have corroborated 

 the results which we had obtained with the kernels. They admit the 

 presence of a deleterious substance in raw cottonseed, but apparently 

 still hold the view that cottonseed meal, the product resulting from 

 cooking the kernels and pressing out the oil, is nontoxic, at least for rats 

 and chickens (9). 



Inasmuch as no comparative experiments with an isolated and purified 

 substance have been reported, we present the results of additional 

 experiments with various animals to supplement those given in our 

 previous experiments, in which rabbits and fowls were used. 



The toxic efltect of an ether extract of raw cottonseed has been well 

 shown in the rat-feeding experiments described by McCollum and co- 

 workers (6) and by Osborne and Mendel (10). This extract contains 

 about 2 per cent of gossypol, which is equivalent to about 0.6 per cent 

 of the weight of the kernels from which the extract is obtained. Our 

 rat diet, containing 20 per cent of this extracted oil, caused prompt 

 decline in grown rats. Osborne and Mendel (10) used as little as i per 



1 Reference is made by ntunber (italic) to "I,iterature cited," pp. loo-ioi. 



Journal of Agricultural Research, Vol. XII, No. 2 



Washington, D. C. Jan. 14. 1918 



Im Key No. N. C— 8 



(83) 



