Structure Identification and Toxicity Assessment of an Arginine-based Heterocyclic Amine
Heterocyclic Amines (HCAs) are cancer causing molecules formed from the high temperature cooking of creatine, an animal muscle tissue amino acid, with various other amino acids. A 1994 paper suggested that mutagenic compounds are formed when arginine, found in many plants, is cooked with one other amino acids such as threonine, phenylalanine, or tryptophan. In this research, the Ames test substantiated the mutagenic claim on a bulk mixture, but no further chemical separations and analyses were performed to identify specific chemical structures. Our research is centered on the reaction products of arginine with other amino acids, beginning with phenylalanine, at high cooking temperatures. We have isolated and begun to characterize two lead candidates following a similar synthesis and separation protocols as described in this 1994 paper and other, more recent, articles. However, the amounts we have isolated are so miniscule, 20-40 micrograms, that molecular characterization techniques (e.g. NMR) have not yielded clear information to generate a specific molecular structure. Thus, we have been scaling up our efforts and learning new techniques to analyze small samples. We are close to identifying the molecular structure of our first candidates. These candidates will then need to have their mutagenicity assessed via Ames test, which we have been developing with the help of Dr. Robert Zdor, AU Biology Department. We have focused on the reaction products of arginine cooked with phenylalanine, but we need to repeat all of this work for arginine reacted with the many other amino acids.