328 ASCORBIC ACID 



(4) Vitamin E. A number of substances, so-called antioxidants, may be 

 associated with each other as synergists in protecting other substances 

 against oxidation. Vitamin E is one of the most potent members of this 

 group. 



Golumbic and MattilF^^ observed that ascorbic acid increases the activ- 

 ity of tocopherols in preventing the oxidation of vegetable fats. Golumbic^^^ 

 found that ascorbic acid retarded the oxidation of tocopherol also in animal 

 fat. Ascorbic acid was oxidized by the fat but at a much slower rate than 

 was the tocopherol. Calkins and MattilF®" had shown earlier that the oxi- 

 dation of ascorbic acid is catalyzed by tocopherol in the presence of quinone 

 esters of lard. Golumbic^^^ suggested as an explanation of these phenomena 

 that the antioxidant (tocopherol) was being continually regenerated at the 

 expense of the synergist (e.g., ascorbic acid). Zacharias et al}^^ also found 

 that ascorbic acid protects tocopherols against oxidation. Harris et al.^^'^ 

 studied the content of vitamin C in guinea pigs on low ascorbic acid intake 

 in association with \'ariable ^'itamin E intake. Animals after receiving 6 

 to 10 mg. of ascorbic acid per kilogram of body weight and 0.5 to 1.0 mg. 

 of supplementary tocopherol had a 19 to 22 % increase in ascorbic acid in 

 the liver and a 22 to 6(i % increase in the adrenals as compared to animals 

 not receiving tocopherol. Dam et al.^^^ found that the addition of 0.5% 

 ascorbic acid to a diet deficient in vitamin E prevented the development 

 of sjonptoms of vitamin E deficiency in chicks. Storage of tocopherol in the 

 fatty tissue was much greater in the chicks which received the ascorbic 

 acid. The results suggest that ascorbic acid protects the tocopherol in the 

 tissues. Farmer et al}^^ presented data which suggest a similar effect of 

 ascorbic acid on ^'itamin E in guinea pigs. Fewer animals receiving 2 to 8 

 mg. of ascorbic acid per day, but no supplement of tocopherol, showed 

 muscle degeneration than did those in the group which received only 1 mg. 

 of vitamin C per day. 



(5) Thiamine. Sure et al}^'^ found that the ascorbic acid content of some 

 of the organs of thiamine-deficient rats was notably reduced, whereas fast- 

 ing for 10 to 11 days produced no change in concentration of the vitamin. 

 Kasahara et al.^^^ reported a growth-promoting effect of ascorbic acid 



"8 C. Golumbic and H. A. Mattill, J. Am. Chem. Soc. 63, 1279 (1941). 



'^^ C. Golumbic, Trans. 1st Conf. Biol. Antioxidants, New York, p. 42 (1946). 



•^60 V. P. Calkins and H. A. Mattill, J. Am. Chem. Soc. 66, 239 (1944). 



361 L. Zacharias, P. Goldhaber, and V. E. Kinsey, J. Nutrition 42, .359 (1950). 



362 p. L. Harris, K. C. D. Hickman, and M. R. Woodside, Meeting of the American 

 Chemical Society, Buffalo, N. Y., September, 1942. 



363 H, Dam, I. Kruse, I. Prange, and E. Son-lergaard, Biochein. ct Biophys. Acta 2, 

 501 (1948). 



364 F. A. Farmer, B. C. Mutch, J. M. Hell, L. I). Woolsey, and E. W. Crampton, ./. 

 Nutrition 42, 309 (1950). 



"« M. Kasahara, Y. Nisigawa, and S. Hirao, Klin. Wochschr. 18, 246 (1939). 



