| Abstract
| - To study the formation of fumonisin artifacts and the binding of fumonisins to matrix components(e.g., saccharides and proteins) in thermal-treated food, model experiments were performed. FumonisinB1 and hydrolyzed fumonisin B1 were incubated with α-d-glucose and sucrose (mono- and disaccharidemodels), with methyl α-d-glucopyranoside (starch model), and with the amino acid derivatives N-α-acetyl-l-lysine methyl ester and BOC-l-cysteine methyl ester (protein models). The reaction productsformed were analyzed by liquid chromatography−electrospray ionization−tandem mass spectrometry.The incubation of d-glucose with fumonisin B1 or hydrolyzed fumonisin B1 resulted in the formationof Amadori rearrangement products. Whereas conjugates were found following the reaction of sucrose,methyl α-d-glucopyranoside, and the amino acid derivatives with fumonisin B1, the heating withhydrolyzed fumonisin B1 yielded no artifacts. For structural determination, the stable reaction productformed by heating of methyl α-d-glucopyranoside (as starch model) with fumonisin B1 was purifiedand identified by nuclear magnetic resonance spectroscopy as the diester of the fumonisin tricarballylicacid side chains with methyl α-d-glucopyranoside. These model experiments demonstrate thatfumonisins are able to bind to polysaccharides and proteins via their two tricarballylic acid side chains. Keywords: Fumonisin B1; hydrolyzed fumonisin B1; artifacts; binding; matrix components; LC-ESI-MS/MS; model experiments; thermally treated food
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