REACTIONS OF FURFURAL AND METHYLFURFURAL WITH DNA

Furfural and methylfurfural are dietary mutagens and are present in va rious food products and beverages. The alkaline-induced unwinding of c alf thymus DNA permitted the measurement of the number of strand break s formed by furfural and methylfurfural, as a function of reaction tim e with these mutagenic agents. At the fixed DNA bp/mutagens molar rati o of 1:4, furfural treatment resulted in the formation of almost three times as many strand breaks at the end of 16 h reaction. In the prese nce of 0.2 M NaCl, a 60% reduction in strand breaks occurred in the ca se of furfural but only 25% with methylfurfural. It is also found that only in the case of methylfurfural treatment did depurination lead to the degradation of DNA, possibly through the alkylation of DNA bases and phosphates. These results suggest that furfural and methylfurfural may act on DNA by different reaction mechanisms.