ヤツメウナギのビタミン含量

抄録

Vitamin contents were determined in the lamprey, Entosphenus japonicus Martens, a fish popularly known to be rich in nourishment. Vitamin A content in the flesh was found to be 99-995 I.U.per g of tissue, the highest figures ever observed in the flesh of fish. In the liver it was 1,010-17,300 I.U.per g. A similar high content was found in the testis while only a trace of vitamin A could be found in the testis of other fishes. The intestine was also found very rich in vitamin A, as the amount in the intestine was almost one half of total vitamin A in the whole body. Although the fish contains much vitamin A already at its very young stage, the contents in the various organs become still higher towards the spawning season. Even in dried products of the fish a considerable amount of vitamin A remains. Thiamine in the skin was found richer than that in usual fishes, with the content being much greater in the dorsal side than in the ventral skin. Vitamin B_<12> was also found rich in the flesh and skin.