Detection of alpha-dicarbonyl compounds in Maillard reaction systems and in vivo

alpha -Dicarbonyl compounds are of major interest in food chemistry and bio chemistry as important precursors of, for example, protein modifications an d flavor. Due to their high reactivity most of the published structures wer e identified and quantitated as stable derivatives after reaction with trap ping reagents. However, the present study showed for the first time that th e trapping reagents are of dramatic impact on the final qualitative and qua ntitative alpha -dicarbonyl spectrum. As important representatives, aminogu anidine and o-phenylenediamine were used to compare trapping characteristic s and to monitor the dicarbonyl structures arising from the degradation of an Amadori compound. Dicarbonyl structures with a reductone moiety could no t be or were only insufficiently detected by slow-reacting reagents such as aminoguanidine. On the other hand, fast-reacting chemicals such as o-pheny lenediamine imposed high oxidative stress on the investigated system and le d to enhanced or false positive formation of dicarbonyl compounds generated by oxidative pathways.