Submitted to: Journal of Agricultural and Food Chemistry
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: December 14, 2001
Publication Date: N/A
Interpretive Summary: The Maillard reaction is responsible for the development of many of the aromas and tastes of cooked food. It involves the reaction of reducing sugars, i.e. glucose and fructose, with the primary amine groups of amino acids. Fumonisin B1 (FB1), a fungal toxin commonly found in corn, also contains a primary amine group. It was shown that FB1 could react in a similar way with glucose to give the title product. FB1 derivatives that do not have a primary amine group are much less toxic than FB1. This reaction maybe the first step in a series of reaction leading to reduced toxicity in cooked corn-based products containing low levels of FB1.
Technical Abstract: Incubation of fumonisin B1 and D-glucose in aqueous solutions resulted in the formation of N-(1-deoxy-D-fructos-1-yl) fumonisin B1 in addition to the previously reported N-(carboxymethyl) fumonisin B1. N-(1-Deoxy-D-fructos-1-yl) fumonisin B1 is the first stable product formed after the Amadori rearrangement of the Schiff base formed by reaction of the primary amine of fumonisin B1 and the aldehyde group of D-glucose. N-(1-deoxy-D-fructos-1-yl) fumonisin B1 was synthesized by reacting fumonisin B1 with an excess of D-glucose in methanol and heating for 6 hours at 64 degrees C. It was purified using tC18 and strong-cation exchange (SCX) solid-phase extraction cartridges and characterized by NMR and liquid chromatography-mass spectrometry (LC-MS). Subsequently, N,N-dimethylformamide was found to be a better reaction solvent. It only required heating the reaction mixture for 2-3 hours at 64 degrees C and eliminated the formation of methyl esters. Alkaline hydrolysis of N-(1-deoxy-D-fructos-1-yl) fumonisin B1 gave a mixture of hydrolyzed fumonisin B1 and hydrolyzed N-(carboxymethyl) fumonisin B1.