title: HPLC characterization of betalains from plants in the amaranthaceae.
abstract: HPLC characterization of reversed-phase (RP) high-performance liquid chromatography (HPLC) has been widely used in separation and identification of plant pigments. An effective RP-HPLC-based method is established to systematically isolate, identify, and quantitate the betalain pigments in the plants of 37 species of eight genera in the Amaranthaceae. A total of 16 betacyanins and three betaxanthins are characterized mainly using the RP-HPLC method and also with the aid of mass spectroscopy. The identified betacyanins include eight amaranthine-types, six gomphrenin-types, and two betanin-types. They are also divided into six simple (nonacylated) betacyanins and 10 acylated betacyanins. Acylated betacyanins are identified as betanidin 5-O-beta-glucuronosylglucoside or betanidin 6-O-beta-glucoside acylated with ferulic, p-coumaric, or 3-hydroxy-3-methylglutaric acids. Three betaxanthins were separated from Celosia species in the Amaranthaceae and identified to be immonium conjugates of betalamic acid with dopamine, 3-methoxytyramine, and (S)-tryptophan; the latter two are found to be new betaxanthins from plants.
authors.affiliation: Department of Botany, The University of Hong Kong, Pokfulam Road, Hong Kong.
authors.forename: Yizhong
authors.initials: Y
authors.lastname: Cai
authors.forename: Mei
authors.initials: M
authors.lastname: Sun
authors.forename: Harold
authors.initials: H
authors.lastname: Corke
mesh_terms: D027703:Amaranthaceae / Q000737:chemistry*; D050858:Betalains / Q000032:analysis* / Q000737:chemistry; D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D013058:Mass Spectrometry; D013056:Spectrophotometry, Ultraviolet
chemical_list: D050858:Betalains