| Abstract: | A method to determine S-methyl methionine (vitamin U) in plants has been devised. The method includes S-methyl methionine extraction extract purification on cationite KU-2 in the NH4+-form, S-methyl methionine eluation with 2n water solution of NH4OH from the cation exchange resin, eluate evaporation in vacuo, dissolution of the residue in a minimal amount of water acidified with hydrochloric acid, electrophoretic separation of S-methyl methionine from basic amino acids, ninhydrine development of the electrophoregram, methanol eluation of the spot corresponding to S-methyl methionine, and colorimetry of the solution at 506 mmu. Relative error is +/-2.5%. |
