抄録
Studies were carried out to elucidate the chemical nature of the desmutagenic factor of Burdock (Arctium lappa LINNE), Which is shown to be a complex polymer having a molecular weight of about 300, 000.5) Its desmutagenic effects are demonstrated on indirect mutagens such as Trp-P-1 and Trp-P-2, as well as on direct mutagens such as 2-nitro-l, 4-diamino benzene and 4-nitro-l, 2-diamino benzene. The present findings suggest that this factor is not a protein because of the low content of nitrogen and the non-color reaction of its hydrolysate with ninhydrin. The desmutagenic factor probably possesses carboxyl groups as indicated by a 13C-NMR spectrum, potentiometric titration and analysis of its pyrolysates. This analysis of the factor's pyrolysates and its reductive degradation substances on the GC-mass spectrum provided evidence that the factor also has an aromatic ring as a basic structure. The factor may be a lignin-like compound having a 10% sugar content.
