Purification and molecular structure of digalactosyl myo-inositol (DGMI), trigalactosyl myo-inositol (TGMI), and fagopyritol B3 from common buckwheat seeds by NMR.

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-(ß-glucopyranosyl)-nicotinic acid and ß-d-apiofuranosyl-(1→6)-ß-d-(1-O-methyl)-glucopyranoside.

Phenolics, sugars, antimicrobial and free-radical-scavenging activities of Melicoccus bijugatus Jacq. fruits from the Dominican Republic and Florida.

Edible fruits of the native South American tree Melicoccus bijugatus Jacq. are consumed fresh or in traditional food, drink and medicinal preparations. Some therapeutic effects of these fruits may be due to phenolics and sugars. Aqueous acetone, methanol or ethanol tissue extracts of different cultivars or collections of M. bijugatus fruits from the Dominican Republic and Florida were analyzed for total phenolics and free radical scavenging activity by UV-vis spectroscopy, sugars by gas chromatography, and antimicrobial activity by the disc diffusion assay. Total phenolics and free radical scavenging activities ranked: seed coat > embryo > pulp extracts. Montgomery cultivar fruits had the highest total phenolics. For sugars: pulp > embryo and highest in Punta Cana fruit pulp. In all extracts: sucrose > glucose and fructose. Glucose:fructose ratios were 1:1 (pulp) and 0.2:1 (embryo). Pulp extracts had dose-response antibacterial activity and pulp and embryo extracts had antifungal activity against one yeast species. Phenolics and sugars were confirmed with thin-layer chromatography and nuclear magnetic resonance. Sugar-free pulp fractions containing phenolics had slightly more antimicrobial activity than H2O-soluble pulp fractions with sugars. Results indicate M. bijugatus fruits contain phenolics, sugars and other H2O-soluble compounds consistent with therapeutic uses.

Characterization of phenolics by LC-UV/vis, LC-MS/MS and sugars by GC in Melicoccus bijugatus Jacq. 'Montgomery' fruits.

Fruits of the native South American tree Melicoccus bijugatus Jacq. (Sapindaceae) are consumed for both dietary and medicinal purposes, but limited information is available about the phytochemistry and health value of M. bijugatus fruits. Fruit tissues of the Florida Montgomery cultivar were assessed for sugars, using gas chromatography, and for total phenolics, using UV spectroscopy. Reverse phase high performance liquid chromatography (HPLC) fingerprints of crude methanolic pulp, embryo and seed coat extracts were obtained at 280 nm. Phenolics were characterised by both HPLC UV/vis analysis and HPLC electrospray ionization tandem mass spectrometry. Major sugars detected in the pulp and embryo extracts were sucrose, followed by glucose and fructose. The glucose:fructose ratio was 1:1 in the pulp and 0.1:1 in the embryo. Total phenolic concentrations of the fruit tissues were in the order: seed coat > embryo > pulp. Phenolic acids were identified mostly in pulp tissues. Phenolic acids, flavonoids, procyanidins and catechins were identified in embryo tissues, and higher molecular weight procyanidins were identified in seed coat tissues. This study provides new information about the phytochemistry and the potential health value of the Montgomery cultivar M. bijugatus fruit tissues.

Molecular structure of lathyritol, a galactosylbornesitol from Lathyrus odoratus seeds, by NMR.

The molecular structure of galactosyl-D-(-)-bornesitol, a novel compound isolated from sweet pea seeds, was determined to be alpha-D-galactopyranosyl-(1-->3)-1-O-methyl-1D-myo-inositol by 1D and 2D NMR spectroscopy and is assigned the trivial name lathyritol.