title: Control of dehydrodiferulate cross-linking in pectins from sugar-beet tissues.
abstract: Pectins were extracted from roots, petioles and leaves of sugar beet, and cross-linked using hydrogen peroxide and peroxidase. The effects on dehydrodiferulate formation were monitored by HPLC and TLC. Dehydrodimers were formed in different proportions to those found in vivo. There was a net loss of around 50% of the phenolic groups (monomers plus dimers) during dimerisation. Gel filtration showed that root and petiole pectin, but not leaf pectin, increased in molecular weight during cross-linking. The effects of varying the cross-linking conditions were investigated, and it was found that hydrogen peroxide concentration was the most important factor in controlling both the type and amount of dehydrodiferulate formed.
authors.affiliation: Department of Biology, American University of Beirut, Beirut, Lebanon.
authors.forename: Elias A -H
authors.initials: EA
authors.lastname: Baydoun
authors.forename: Natalie
authors.initials: N
authors.lastname: Pavlencheva
authors.forename: Carol M
authors.initials: CM
authors.lastname: Cumming
authors.forename: Keith W
authors.initials: KW
authors.lastname: Waldron
authors.forename: Christopher T
authors.initials: CT
authors.lastname: Brett
mesh_terms: D027461:Beta vulgaris / Q000737:chemistry* / Q000378:metabolism; D002850:Chromatography, Gel; D002855:Chromatography, Thin Layer; D003373:Coumaric Acids / Q000737:chemistry / Q000378:metabolism*; D003432:Cross-Linking Reagents / Q000737:chemistry; D019281:Dimerization; D006861:Hydrogen Peroxide / Q000737:chemistry; D010368:Pectins / Q000737:chemistry* / Q000302:isolation & purification; D009195:Peroxidase / Q000737:chemistry; D010636:Phenols / Q000737:chemistry / Q000302:isolation & purification; D018515:Plant Leaves / Q000378:metabolism; D018517:Plant Roots / Q000378:metabolism; D018514:Plant Structures / Q000378:metabolism; D000644:Quaternary Ammonium Compounds / Q000737:chemistry; D013696:Temperature
chemical_list: D003373:Coumaric Acids; D003432:Cross-Linking Reagents; D010636:Phenols; D000644:Quaternary Ammonium Compounds; D010368:Pectins; C004999:ferulic acid; D006861:Hydrogen Peroxide; D009195:Peroxidase