title: New acylated anthocyanins from purple yam and their antioxidant activity.
abstract: Purple yam (Dioscorea alata L.), which is widely distributed in tropical and subtropical regions, is characterized by its color and viscosity. Previous studies have shown that purple yams contain a variety of acylated anthocyanins that exhibit higher levels of antioxidant activity than the corresponding nonacylated compounds. In this study, the pigments found in purple yams from the Philippines (D. alata) were isolated and evaluated in terms of antioxidant activity. Four new acylated anthocyanins, alanins (1-4) were isolated from the MeOH extracts of purple yam, which were subsequently determined to be cyanidin (1, 2, and 4) and peonidin (3) type compounds, along with four known anthocyanins (5-8). The structures of 1-4 were determined by spectroscopic methods, including NMR and MS analyses. The antioxidant activities of anthocyanins 1-8 were investigated using oxygen radical absorbing capacity and ferric reducing antioxidant power assays.
authors.affiliation: a Department of Food and Nutritional Sciences , University of Shizuoka , Shizuoka , Japan.
authors.forename: Chiemi
authors.initials: C
authors.lastname: Moriya
authors.forename: Takahiro
authors.initials: T
authors.lastname: Hosoya
authors.forename: Sayuri
authors.initials: S
authors.lastname: Agawa
authors.forename: Yasumasa
authors.initials: Y
authors.lastname: Sugiyama
authors.forename: Ikuko
authors.initials: I
authors.lastname: Kozone
authors.forename: Kazuo
authors.initials: K
authors.lastname: Shin-Ya
authors.forename: Norihiko
authors.initials: N
authors.lastname: Terahara
authors.forename: Shigenori
authors.initials: S
authors.lastname: Kumazawa
mesh_terms: D000215:Acylation; D000872:Anthocyanins / Q000737:chemistry* / Q000302:isolation & purification / Q000494:pharmacology; D000975:Antioxidants / Q000737:chemistry* / Q000302:isolation & purification / Q000494:pharmacology; D027742:Dioscorea / Q000737:chemistry; D009682:Magnetic Resonance Spectroscopy; D018517:Plant Roots / Q000737:chemistry
chemical_list: D000872:Anthocyanins; D000975:Antioxidants; C017154:cyanidin; C473205:peonidin
keywords: Dioscorea alata; anthocyanin; antioxidant activity; purple yam; the Philippines