[On the problems with respect to the formation of N-nitroso compound precursors when using alkylating agents in the fumigation of foodstuffs. II. N-methylation of various amino acids by the action of methyl bromide (author's transl)].

The aim of this investigation was to determine whether the insecticide, methyl bromide, used in the treatment of foodstuffs reacts with the amino group of various amino acids in the sense of an N-methylation, thus generating substrates which can be converted to nitroso compounds, i.e. those which are the precursors of cancerogenic compounds. Cooled liquid methyl bromide was added to the aqueous solutions of five amino acids at different pH values. Samples for thin layer chromatographic separation of the derivatives formed were taken after 1, 2, 3, 4, and 8 hours. The method of proving used was at ninhydrine reaction. The results show that methyl bromide reacts with the amino acids glycine, alanine, valine, leucine and glutamic acid to degrees depending upon the pH value and the length of the reaction. The corresponding N-methyl derivatives are formed, namely sarcosine, N-methyl alanine, N-methyl valine, N-methyl leucine, and N-methyl glutamic acid.