Browsing Division of Molekulare Strukurbiologie (MOSB) by Authors
Isolation of isomangiferin from honeybush (Cyclopia subternata) using high-speed counter-current chromatography and high-performance liquid chromatography.de Beer, Dalene; Jerz, Gerold; Joubert, Elizabeth; Wray, Victor; Winterhalter, Peter; ARC Infruitec-Nietvoorbij, Stellenbosch, South Africa. email@example.com (2009-05-08)Isomangiferin was isolated from Cyclopia subternata using a multi-step process including extraction, liquid-liquid partitioning, high-speed counter-current chromatography (HSCCC) and semi-preparative reversed-phase high-performance liquid chromatography (HPLC). Enrichment of phenolic compounds in a methanol extract of C. subternata leaves was conducted using liquid-liquid partitioning with ethyl acetate-methanol-water (1:1:2, v/v). The enriched fraction was further fractionated using HSCCC with a ternary solvent system consisting of tert-butyl methyl ether-n-butanol-acetonitrile-water (3:1:1:5, v/v). Isomangiferin was isolated by semi-preparative reversed-phase HPLC from a fraction containing mostly mangiferin and isomangiferin. The chemical structure of isomangiferin was confirmed by LC-high-resolution electrospray ionization MS, as well as one- and two-dimensional NMR spectroscopy.
Structural characterization of 13(2)-hydroxy-(13(2)-S)-phaeophytin-a from leaves and stems of Amaranthus tricolor isolated by high-speed countercurrent chromatographyJerz, Gerold; Arrey, Tabiwang N.; Wray, Victor; Du, Qizhen; Winterhalter, Peter; Helmholtz Zentrum für Infektionsforschung GmbH (Elsevier Science, 2007)