Induction of 8-azaguanine or ouabain resistant somatic mutation of Chinese hamster lung cells by treatment with tryptophan products.

The basic fraction of tryptophan pyrolysis products (TBF) showed strong mutagenic activity on somatic cells of the lung of Chinese hamsters. In this somatic mutation test, TBF was demonstrated to have 5.6 times higher mutagenicity than diethylnitrosamine (DEN) when mutants were selected with 8-azaguanine, and 13.5-fold higher mutagenicity than DEN when mutants were selected with ouabain. From these findings, it is suggested that pyrolyzates of amino acids may have mutagenic actions on somatic cells of animals, as well as carcinogenic actions.