Toxic effects lysinoalanine

There has been some concern about the effect of alkaline conditions on the formation of toxic amino acids in corn, particularly lysinoalanine (13). However, since lysinoalanine was found in very small amounts in foods prepared under more rigorous conditions than those applied traditionally, and since the lime treatment of corn has been a processing... 

Since lysinoalanine and at least one D-amino acid are toxic to some animals (35), we wished to distinguish their effects in alkali-treated proteins. Such discrimination is possible, in principle, since we have found that acylating the e-amino group of lysine proteins seems to prevent lysinoalanine formation. Since lysinoalanine formation from lysine requires participation of the e-amino group of lysine side chains, acylation of the amino group with acetic anhydride is expected to prevent lysinoalanine formation under alkaline conditions if the protective effect survives the treatment. This is indeed the case (16). 

These studies focused attention on the crosslinked amino acid derivative, lysinoalanine (IAL), and its possible toxicity. Although the treatments used almost certainly caused significant racemization, the possible effect of D-amino acids on the results was not evaluated. 

At present, much emphasis is given to the possible formation of truly toxic substances in processed foodstuffs. The controversy about the possible nephrotoxic effect of lysinoalanine is well known. Erbersdobler found that deoxy-ketosyl-lysine produces cyto-megaly in rats. Wiirzner et found, in our laboratory, that single-cell protein (SCP) induced multi-nucleated epithelial cells in... 

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