抄録
The microbiological method of LEWIS for estimation of PABA was improved on the composition of basal medium and on the treatment of test sample. That is, a considerable amount of L-tyrosine was added to the basal medium and the tyrosine present in sample was removed by adsorbing on charcoal at pH 1 (Table 2). By estimating PABA with the modified method the content in the pyloric coeca of skipjack showed the value of 1.25γ per one gram of dry matter (Table 3).
In the estimation of riboflavin by BARTON-WRIGHT's method, the elimination of riboflavin from peptone and yeast-extract, which was used in the preparation of basal medium, was made by irradiation of ultraviolet ray for 30 minutes. And the concentration of both glucose and yeastextract in the basal medium was duplicated in quantity (Table 4).
By estimating riboflavin with the modified method the content in the pyloric coeca was proved to be 38γ per one gram of dry matter (Table 5).