New Determination Method of Assaying Methionine Strains

A rapid simple ,convenient and highly sensitive determination method of asssaying Methionine was established in this paper. Methionine might be determined colorimetrically from the conversion of nitrothiobenzoate to 5,5′-dithiobis(2- nitrobenzoic acid) by chloramines-T remaining after oxidation of methionine to methionine sulfoxide by a known excess of reagent. The interference of amine acid especially amine acid, containing sulfhydryl groups might be effectively suppressed by reaction with DEPC. The method was applicable to large amount of methionine strains scseening.