1961 年 14 巻 3 号 p. 188-190
The contents of free amino acids in rice were investigated in detail by the combined use of ion exchange chromatography and paper partition chromatography.
Total free amino acids adsorbed on a column of Amberlite-IR-120 (H) were thoroughly eluted with aqueous ammonia (5%), and the combined eluate was taken to dryness in vacuo, after which the residue was dissolved in 10 ml of distilled water.
An aliquot of 0.001 ml of the solution was chromatographed on a sheet of paper by the two-dimensional, ascending development method, using 0.1% acetonic solution of ninhydrin as a chromogenic spray reagent.
Each spot of chromatograms of amino acids was cut off, and to this was added 2 ml of 1% aqueous solution of ninhydrin and 1 ml of 10% aqueous solution of pyridine, and the solution was boiled on a water-bath for 25 min.
Each of the colored eluates was subjected to spectrophotometry at 570 mp (in the case of proline and hydroxyproline at 440 mμ).
The results were tabulated in Table 2.