title: Influence of lignification and feruloylation of maize cell walls on the adsorption of heterocyclic aromatic amines.
abstract: Both epidemiological and experimental data indicate that a diet rich in fiber may reduce cancer risk. One possible mechanism is by adsorbing carcinogens and transporting them out of the body without metabolic activation. We investigated the role of fiber lignification and feruloylation on the adsorption of four of the most relevant heterocyclic aromatic amines in food: 2-amino-3,8-dimethylimidazo[4,5-f]quinoxaline (MeIQx), 2-amino-3-methylimidazo[4,5-f]quinoline (IQ), 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP), and 2-amino-9H-pyrido[2,3-b]indole (AalphaC). Adsorption experiments, under conditions mimicking the small intestine, were carried out using nonlignified and artificially lignified primary maize walls with defined lignin and ferulate/diferulate concentrations and defined lignin compositions. Lignin concentration and composition both influenced the adsorption of heterocyclic aromatic amines, especially the more hydrophobic types. Heterocyclic aromatic amine adsorption increased with lignin concentration. 2-Amino-1-methyl-6-phenylimidazo[4,5-b]pyridine and 2-amino-9H-pyrido[2,3-b]indole were better adsorbed by guaiacyl-rich lignins, 2-amino-3,8-dimethylimidazo[4,5-f]quinoxaline by syringyl-rich lignins, whereas the adsorption of 2-amino-3-methylimidazo[4,5-f]quinoline was not clearly influenced by lignin composition. Nonlignified cell walls adsorbed lesser amounts of heterocyclic aromatic amines. Variations in cell wall feruloylation had no effect on heterocyclic aromatic amine adsorption.
authors.affiliation: Institute of Biochemistry and Food Chemistry, Department of Food Chemistry, University of Hamburg, Grindelallee 117, 20146 Hamburg, Germany.
authors.forename: Carola
authors.initials: C
authors.lastname: Funk
authors.forename: Patrick
authors.initials: P
authors.lastname: Weber
authors.forename: Janina
authors.initials: J
authors.lastname: Thilker
authors.forename: John H
authors.initials: JH
authors.lastname: Grabber
authors.forename: Hans
authors.initials: H
authors.lastname: Steinhart
authors.forename: Mirko
authors.initials: M
authors.lastname: Bunzel
mesh_terms: D000327:Adsorption; D000588:Amines / Q000737:chemistry / Q000378:metabolism*; D002473:Cell Wall / Q000737:chemistry* / Q000378:metabolism; D003373:Coumaric Acids / Q000032:analysis*; D006571:Heterocyclic Compounds / Q000737:chemistry / Q000378:metabolism*; D057927:Hydrophobic and Hydrophilic Interactions; D008031:Lignin / Q000032:analysis*; D003313:Zea mays / Q000648:ultrastructure*
chemical_list: D000588:Amines; D003373:Coumaric Acids; D006571:Heterocyclic Compounds; D008031:Lignin; C004999:ferulic acid