We examined the reactivity of the N‐hydroxyamino derivative of a carcinogenic heterocyclic amine, 2‐amino‐1‐methyl‐6‐phenylimidazo[4,5‐b]pyridine (PhIP), after its O‐acetylation with four 2′‐deoxyribonucleoside 3′‐monophosphates. 32P‐Postlabeling analysis demonstrated that the levels of adducts with 2′‐deoxyguanosine 3′‐moiiophosphate were much higher than those with the other three nucleotides. 1H‐NMR, mass spectral and UV absorption spectral analyses of the major adducts formed by N‐acetoxy‐PhIP with 2′‐deoxyguanosine and with its phosphate esters indicated that PhIP bound at the C‐8 position of guanine, as previously demonstrated with other heterocyclic amines.

The degradation of nitrite and the inhibition towards formation of carcinogenic nitrosamines by melanoidins, produced from the glucose-glycine system were investigated at various conditions. The degradation ofnitrite was highest at pH1.2 (29%), when the ratio ofmelanoidins to nitrite was 1 : 3. The inhibition towards formation of nitrosamines by melanoidins had the same tendency as the degradation of nitrite, the inhibition also being highest at pH 1.2 (99%). In addition, melanoidins after nitrite treatment exhibited a little higher mutagenicity and much stronger desmutagenicity than those of the original melanoidins. The change of the structure of melanoidins after treating with nitrite was also investigated by HPLCand CP-MASNMR.The Maillard reaction is very important in food manufacturing, and its results can be either desirable or undesirable.Recently, re-

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