title: Molecular heterogeneity of arabinogalactan-protein from Coffea arabica instant coffee.
abstract: Arabinogalactan-protein complex (AGP), isolated from freeze-dried instant coffee powder of Coffea arabica beans, was subjected to ion-exchange chromatography. Stepwise elution with water and solutions of sodium chloride with increasing ionic strength afforded eight fractions (F1-F8). Chemical analyses have shown that compositions of individual conjugates varied in carbohydrate and protein contents, molecular mass and slightly in monosaccharide composition. Protein content was increasing by increasing ionic strength of the eluent and it was confirmed also by FT-IR spectra. NMR study has shown that carbohydrate moieties in individual ion exchange fractions differed in the degree of backbone and side chains branching. Performed study has confirmed a molecular heterogeneity of arabinogalactan-protein complex present in a commercial instant coffee.
authors.affiliation: Institute of Chemistry, Center for Glycomics, Slovak Academy of Sciences, Dúbravská cesta 9, 845 38 Bratislava, Slovakia. chemcape@savba.sk
authors.forename: P
authors.initials: P
authors.lastname: Capek
authors.forename: M
authors.initials: M
authors.lastname: Matulová
authors.forename: L
authors.initials: L
authors.lastname: Navarini
authors.forename: F
authors.initials: F
authors.lastname: Suggi-Liverani
mesh_terms: D005591:Chemical Fractionation; D002852:Chromatography, Ion Exchange; D040503:Coffea / Q000737:chemistry*; D009682:Magnetic Resonance Spectroscopy; D008970:Molecular Weight; D009005:Monosaccharides / Q000737:chemistry* / Q000302:isolation & purification; D009088:Mucoproteins / Q000737:chemistry* / Q000302:isolation & purification; D010940:Plant Proteins / Q000737:chemistry / Q000302:isolation & purification; D011208:Powders / Q000737:chemistry; D012639:Seeds / Q000737:chemistry*; D017550:Spectroscopy, Fourier Transform Infrared
chemical_list: D009005:Monosaccharides; D009088:Mucoproteins; D010940:Plant Proteins; D011208:Powders; C006619:arabinogalactan proteins