Abstract
The existence of glucose conjugates of fumonisin B&sub2; (FB&sub2;) and fumonisin B&sub3; (FB&sub3;) in corn powder was confirmed for the first time. These "bound-fumonisins" (FB&sub2; and FB&sub3; bound to glucose) were identified as N-(1-deoxy-D-fructos-1-yl) fumonisin B&sub2; (NDfrc-FB&sub2;) and N-(1-deoxy-D-fructos-1-yl) fumonisin B&sub3; (NDfrc-FB&sub3;) respectively, based on the accurate mass measurements of characteristic ions and fragmentation patterns using high-resolution liquid chromatography-Orbitrap mass spectrometry (LC-Orbitrap MS) analysis. Treatment on NDfrc-FB&sub2; and NDfrc-FB&sub3; with the o-phthalaldehyde (OPA) reagent also supported that D-glucose binding to FB&sub2; and FB&sub3; molecules occurred to their primary amine residues.