Bound fumonisin B1: analysis of fumonisin-B1 glyco and amino acid conjugates by liquid chromatography-electrospray ionization-tandem mass spectrometry.
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. Fumonisin B(1) and hydrolyzed fumonisin B(1) were incubated with alpha-d-glucose and sucrose (mono- and disaccharide models), with methyl alpha-d-glucopyranoside (starch model), and with the amino acid derivatives N-alpha-acetyl-l-lysine methyl ester and BOC-l-cysteine methyl ester (protein models). The reaction products formed were analyzed by liquid chromatography-electrospray ionization-tandem mass spectrometry. The incubation of d-glucose with fumonisin B(1) or hydrolyzed fumonisin B(1) resulted in the formation of Amadori rearrangement products. Whereas conjugates were found following the reaction of sucrose, methyl alpha-d-glucopyranoside, and the amino acid derivatives with fumonisin B(1), the heating with hydrolyzed fumonisin B(1) yielded no artifacts. For structural determination, the stable reaction product formed by heating of methyl alpha-d-glucopyranoside (as starch model) with fumonisin B(1) was purified and identified by nuclear magnetic resonance spectroscopy as the diester of the fumonisin tricarballylic acid side chains with methyl alpha-d-glucopyranoside. These model experiments demonstrate that fumonisins are able to bind to polysaccharides and proteins via their two tricarballylic acid side chains.
Seefelder
Walburga
W
Institut für Lebensmittelchemie, Westfälische Wilhelms-Universität Münster, Corrensstrasse 45, 48149 Münster, Germany.
Knecht
Anja
A
Humpf
Hans-Ulrich
HU
D000596:Amino Acids / Q000378:metabolism*; D001665:Binding Sites; D002853:Chromatography, Liquid; D037341:Fumonisins / Q000737:chemistry / Q000378:metabolism*; D005947:Glucose / Q000378:metabolism; D006358:Hot Temperature; D006868:Hydrolysis; D009682:Magnetic Resonance Spectroscopy; D008757:Methylglucosides / Q000378:metabolism; D011134:Polysaccharides / Q000378:metabolism*; D021241:Spectrometry, Mass, Electrospray Ionization; D013395:Sucrose / Q000378:metabolism
D000596:Amino Acids; D037341:Fumonisins; D008757:Methylglucosides; D011134:Polysaccharides; C056933:fumonisin B1; C027020:methylglucoside; D013395:Sucrose; D005947:Glucose