Formation of the comutagenic beta-carboline norharman in a simple tryptophan-containing model system at low temperature (40 degrees C-80 degrees C).
The formation of the comutagenic tryptophan derivate norharman in heat-processed food is a well known phenomenon. As a first step to investigate the possible formation of norharman during food storage particularly in regard to fortified food we developed a model system and studied the non-enzymatic formation of the comutagen at temperatures below 100 degrees C. With standard conditions (4 h, 80 degrees C) iron and copper (Fe2+/Cu2+) was required for the formation of norharman. Addition of glucose to the reaction mixture increased the norharman formation and a plateau was reached with 400 microM tryptophan. Decreasing the reaction temperature to 40 degrees C led to a significant formation of norharman after 72 hours of incubation indicating that the formation of norharman can take place at temperatures that are close to ranges occurring during food storage.
Ziegenhagen
R
R
Federal Institute for Health Protection of Consumers and Veterinary Medicine, Berlin, Germany. r.ziegenhagen@bgvv.de
Boczek
P
P
Viell
B
B
D002243:Carbolines / Q000032:analysis / Q000737:chemistry*; D005511:Food Handling; D006247:Harmine / Q000031:analogs & derivatives* / Q000032:analysis / Q000737:chemistry; D006358:Hot Temperature; D008956:Models, Chemical; D009153:Mutagens / Q000032:analysis / Q000737:chemistry*; D013816:Thermodynamics; D014364:Tryptophan / Q000737:chemistry*
D002243:Carbolines; D009153:Mutagens; D006247:Harmine; D014364:Tryptophan; C010262:norharman