title: Characterization of fumonisin A-series by high-resolution liquid chromatography-orbitrap mass spectrometry.
abstract: Fumonisin A-series (FAs) in a reference material of corn sample that was naturally contaminated with fumonisins was characterized using high-resolution liquid chromatography-Orbitrap mass spectrometry (LC-Orbitap MS). Peaks for fumonisin B1 (FB1), fumonisin B2 (FB2), and fumonisin B3 (FB3), in addition to three peaks corresponding to unknown compounds I, II, and III, were detected in the chromatogram for the corn sample. Fragment ion analysis for FB1, FB2, and FB3 showed that while the ions formed at m/z values of 200-800 were similar to those formed by the cleavage of the tricarballylic acids and the hydroxyl groups, the fragmentation patterns at m/z values of 50-200 varied depending on the hydroxyl group locations in the compounds. Fragment ion analysis of compounds I-III revealed structural similarities to FBs, only differing by an additional C2H2O in the unknown compounds. Using these results and by comparing the product ion mass spectra of compound I with fumonisin A1 (FA1) synthesized from FB1 standards, compounds I-III were hypothesized to be N-acetyl analogs of FBs: fumonisins A1 (FA1), A2 (FA2), and A3 (FA3). The method for determining concentrations was validated with FA1, FB1, FB2, and FB3 standards and applied to analyze the reference material. The FB1, FB2, and FB3 analytical levels were within acceptance limits and the amount of FA1 in the material was ~15% of FB1 amount at 4.2 mg/kg.
authors.affiliation: Research Laboratories for Food Safety Chemistry, Asahi Group Holdings, Ltd., 1-21, Midori 1-chome, Moriya-shi, Ibaraki 302-0106, Japan. masayoshi.tamura@asahigroup-holdings.com.
authors.forename: Masayoshi
authors.initials: M
authors.lastname: Tamura
authors.affiliation: Research Laboratories for Food Safety Chemistry, Asahi Group Holdings, Ltd., 1-21, Midori 1-chome, Moriya-shi, Ibaraki 302-0106, Japan. naoki.mochizuki@asahigroup-holdings.com.
authors.forename: Naoki
authors.initials: N
authors.lastname: Mochizuki
authors.affiliation: Research Laboratories for Food Safety Chemistry, Asahi Group Holdings, Ltd., 1-21, Midori 1-chome, Moriya-shi, Ibaraki 302-0106, Japan. yasushi.nagatomi@asahigroup-holdings.com.
authors.forename: Yasushi
authors.initials: Y
authors.lastname: Nagatomi
authors.affiliation: Institute of Medical, Pharmaceutical and Health Sciences, Kanazawa University, Kakuma-machi, Kanazawa-shi, Kanazawa 920-1192, Japan. toriba@p.kanazawa-u.ac.jp.
authors.forename: Akira
authors.initials: A
authors.lastname: Toriba
authors.affiliation: Institute of Medical, Pharmaceutical and Health Sciences, Kanazawa University, Kakuma-machi, Kanazawa-shi, Kanazawa 920-1192, Japan. hayakawa@p.kanazawa-u.ac.jp.
authors.forename: Kazuichi
authors.initials: K
authors.lastname: Hayakawa
mesh_terms: D002853:Chromatography, Liquid / Q000379:methods; D005506:Food Contamination / Q000032:analysis*; D037341:Fumonisins / Q000032:analysis* / Q000737:chemistry; D013058:Mass Spectrometry / Q000379:methods; D003313:Zea mays / Q000737:chemistry*
chemical_list: D037341:Fumonisins; C000602130:fumonisin A3