title: Identification of catechin oligomers from apple (Malus pumila cv. Fuji) in matrix-assisted laser desorption/ionization time-of-flight mass spectrometry and fast-atom bombardment mass spectrometry.
abstract: Molecular size information for polymerized catechin larger than the decamer in unripe apple was obtained by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry and by fast-atom bombardment mass spectrometry. Matrix-assisted laser desorption/ionization time of flight mass spectrometry provided evidence for the pentadecamer using trans-3-indoleacrylic acid as the matrix in the presence of silver ion. Even in the absence of silver ion, the dodecamer and undecamer were observed in the positive- and negative-ion modes, respectively. Fast-atom bombardment mass spectrometry also afforded evidence for the undecamer in both positive- and negative-ion modes.
authors.affiliation: National Food Research Institute, Ministry of Agriculature, Forestry and Fisheries, Ibaraki, Japan.
authors.forename: M
authors.initials: M
authors.lastname: Ohnishi-Kameyama
authors.forename: A
authors.initials: A
authors.lastname: Yanagida
authors.forename: T
authors.initials: T
authors.lastname: Kanda
authors.forename: T
authors.initials: T
authors.lastname: Nagata
mesh_terms: D002392:Catechin / Q000032:analysis*; D005638:Fruit / Q000737:chemistry*; D016339:Spectrometry, Mass, Fast Atom Bombardment; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; D013634:Tannins / Q000032:analysis
chemical_list: D013634:Tannins; D002392:Catechin