title: Purification and molecular structure of digalactosyl myo-inositol (DGMI), trigalactosyl myo-inositol (TGMI), and fagopyritol B3 from common buckwheat seeds by NMR.
abstract: Three galactosyl cyclitols, digalactosyl myo-inositol (assigned the trivial name DGMI), trigalactosyl myo-inositol (assigned the trivial name TGMI), and trigalactosyl d-chiro-inositol (fagopyritol B3), were isolated from common buckwheat (Fagopyrum esculentum Moench) seeds. Structures of the three compounds were determined by 2D NMR spectroscopy. DGMI is α-d-galactopyranosyl-(1→6)-α-d-galactopyranosyl-(1→1)-1l-myo-inositol, TGMI is α-d-galactopyranosyl-(1→6)-α-d-galactopyranosyl-(1→6)-α-d-galactopyranosyl-(1→1)-1l-myo-inositol, and fagopyritol B3 is α-d-galactopyranosyl-(1→6)-α-d-galactopyranosyl-(1→6)-α-d-galactopyranosyl-(1→2)-1d-chiro-inositol. DGMI and TGMI are higher oligomers of galactinol, a major galactosyl donor in plant seeds. Fagopyritol B3 is a higher oligomer of the fagopyritol B series and one of six fagopyritols found in buckwheat seeds and in the bran milling fraction. Samples of TGMI and fagopyritol B3 also contained the compounds N-(β-glucopyranosyl)-nicotinic acid and β-d-apiofuranosyl-(1→6)-β-d-(1-O-methyl)-glucopyranoside.
authors.affiliation: Seed Biology, Department of Crop and Soil Sciences, Cornell University, Ithaca, NY 14853-1901, USA.
authors.forename: Wei
authors.initials: W
authors.lastname: Gui
authors.forename: Bethan A
authors.initials: BA
authors.lastname: Lemley
authors.forename: Ivan
authors.initials: I
authors.lastname: Keresztes
authors.forename: Anthony M
authors.initials: AM
authors.lastname: Condo
authors.forename: Kathryn J
authors.initials: KJ
authors.lastname: Steadman
authors.forename: Ralph L
authors.initials: RL
authors.lastname: Obendorf
mesh_terms: D002240:Carbohydrate Sequence; D004187:Disaccharides / Q000737:chemistry* / Q000302:isolation & purification*; D019612:Fagopyrum / Q000737:chemistry*; D007294:Inositol / Q000737:chemistry* / Q000302:isolation & purification*; D009682:Magnetic Resonance Spectroscopy; D008969:Molecular Sequence Data; D012639:Seeds / Q000737:chemistry*; D014312:Trisaccharides / Q000737:chemistry* / Q000302:isolation & purification*
chemical_list: D004187:Disaccharides; D014312:Trisaccharides; D007294:Inositol
keywords: Buckwheat seed; Digalactosyl myo-inositol; Fagopyritol B3; Galactosyl cyclitol; N-(β-glucopyranosyl)-nicotinic acid; Trigalactosyl myo-inositol