title: Time-course study and effects of drying method on concentrations of gamma-aminobutyric acid, flavonoids, anthocyanin, and 2''-hydroxynicotianamine in leaves of buckwheats.
abstract: Concentrations of gamma-aminobutyric acid (GABA), rutin, minor flavonoids (such as orientin), anthocyanin, and 2''-hydroxynicotianamine (2HN) were quantified in the leaves of common and tartary buckwheat (Fagopyrum esculentum Moench and Fagopyrum tataricum Gaertn., respectively), at 14, 28, and 42 days after sowing (DAS). GABA and rutin concentrations peaked at 42 DAS, whereas anthocyain, 2HN, and minor flavonoid concentrations declined with the age of the plants. However, at 42 DAS, anthocyanin concentrations in the leaves of tartary buckwheat Hokkai T10 leaves were at least 10-fold greater than in the other buckwheats tested. In addition, the effects on target compound concentrations and 1,1-diphenyl-2-picrylhydrazyl radical scavenging activity of three different drying methods (20 h at 40 degrees C, 7 h at 70 degrees C, or lyophilization) were investigated. In general, the drying method had no significant effect on the parameters tested. These results indicate that, in terms of GABA, rutin, and anthocyanin concentrations, leaf powder from 42 day old Hokkai T10 has the potential to be a useful food ingredient, such as Ao-jiru juice.
authors.affiliation: National Agricultural and Food Research Organization for Hokkaido Region, Memuro, Hokkaido, Japan. tsuzu@affrc.go.jp
authors.forename: Tatsuro
authors.initials: T
authors.lastname: Suzuki
authors.forename: Masami
authors.initials: M
authors.lastname: Watanabe
authors.forename: Makiko
authors.initials: M
authors.lastname: Iki
authors.forename: Yasuo
authors.initials: Y
authors.lastname: Aoyagi
authors.forename: Sun-Ju
authors.initials: SJ
authors.lastname: Kim
authors.forename: Yuji
authors.initials: Y
authors.lastname: Mukasa
authors.forename: Satoshi
authors.initials: S
authors.lastname: Yokota
authors.forename: Shigenobu
authors.initials: S
authors.lastname: Takigawa
authors.forename: Naoto
authors.initials: N
authors.lastname: Hashimoto
authors.forename: Takahiro
authors.initials: T
authors.lastname: Noda
authors.forename: Hiroaki
authors.initials: H
authors.lastname: Yamauchi
authors.forename: Chie
authors.initials: C
authors.lastname: Matsuura-Endo
mesh_terms: D000872:Anthocyanins / Q000032:analysis*; D001383:Azetidinecarboxylic Acid / Q000031:analogs & derivatives* / Q000032:analysis; D003890:Desiccation / Q000379:methods*; D019612:Fagopyrum / Q000737:chemistry*; D005419:Flavonoids / Q000032:analysis*; D016166:Free Radical Scavengers / Q000032:analysis; D007700:Kinetics; D018515:Plant Leaves / Q000737:chemistry; D012431:Rutin / Q000032:analysis; D005680:gamma-Aminobutyric Acid / Q000032:analysis*
chemical_list: C534946:2''-hydroxynicotianamine; D000872:Anthocyanins; D005419:Flavonoids; D016166:Free Radical Scavengers; D005680:gamma-Aminobutyric Acid; D012431:Rutin; D001383:Azetidinecarboxylic Acid