Effect of Feeding Wheat Germ Oil on Production of Liver Cancer by Butter-Yellow

Yoshida 1 experimentally produced liver cancer in rats by feeding o-aminoazotoluene, and Kinosita, 2 using dimethylaminoazobenzene, commercially known as butter-yellow, produced liver cancer in a much shorter time. In both cases, rice was used as the basal food for the animals. On the other hand, Fischer-Wasels 3 reported that rats receiving o-aminoazotoluene and bread developed only liver cirrhosis.

Recently Kinosita 4 and Okada 5 showed that the production of liver cancer by dimethylaminoazobenzene is definitely reduced when wheat bread was used as basal diet instead of rice. Vassiliadis 6 found that rats receiving o-aminoazotoluene and a diet of wheat flour showed no tumor at the end of a year. Whereas, if the diet consisted solely of rice and dye substance, a large number of adeno-carcinoma of the liver appeared. The failure of o-aminoazotoluene to produce liver cancer in rats maintained on the diet of wheat was also shown by Ando. 7 These experiments demonstrate that a certain substance of wheat is antagonizing the carcinogenic action of dimethylaminoazobenzene or of o-aminoazotoluene in the body.

The object of the present study is to find whether or not wheat germ oil has any inhibiting effect upon the production of liver cancer in rats induced by the oral administration of butter-yellow. It was shown in a recent communication 8 that the ether extracts of rice-bran and of brewer's yeast contain a substance which is inhibitory to the development of liver cancer in rats by butter-yellow feeding.

Experimental. In the present series of experiments two samples of wheat germ oil were used. One was prepared in the same manner as that of rice-bran oil, i. e., the wheat germ was continuously extracted in Soxhlet extractors with ether for 24 to 48 hours at 50°C. One thousand grams of wheat germ yielded about 70 cc of a yellowish brown oily emulsion.