Abstract
1. Proteins from fresh meat of twenty six of marine fish, fresh-water fish, crustacea and mollusca were prepared and their methionine and threonine contents were determined.
The results showed that meat of aquatic animals are the good sources of these two amino acids.
2. Methionine contents in dehydrated proteins of marin and fresh-water fish, cuttle fish, octopus, sea-cucumber etc. are 3_??_4.8%, except 6.3% of tunny; 2_??_3% in crustaceas and less than 2% in shells.
3. Threonine contents in dehydrated proteins are 3_??_4% in all kinds of fish; about 3% in cuttle fish, octopus, lobster, crub and less in sea-cucumber and shells.
4. Fish meat contains more methionine and threonine than mollusca and crustacea meat and there is almost no difference in their contents according to the kinds of fishes.
