Abstract
1. A method of estimating reduced and oxidized glutathiones in tissues and in biological fluids was described. The principle of the method is analogous to that of determining cysteine and cystine, which has already been set forth by Okada (1929). In this method, first of all, proteins are removed by means of N/4 sulfo-salicylic acid, and the filtrate is divided into two portions. In one portion, reduced glutathione is estimated directly by titration at 0° with the standard iodate solution in the presence of a certain quantity of iodide and starch. In the other, oxidized glutathione, after being reduced into reduced form by boiling the acid solution with zinc powder, is estimated in the same way.
2. For the purpose of establishing this method some preliminary experiments were carried out among which the titration at 0° and the reduction for 20 minutes at the boiling temperature are emphasized.
3. By the use of this method, glutathiones, both reduced and oxidized, were estimated in some animal and plant tissues.
