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This is a postprint of an article published in Gutzeit, D., Wray, V., Winterhalter, P., Jerz, G. Preparative isolation and purification of flavonoids and protocatechuic acid from sea buckthorn juice concentrate (Hippophae? rhamnoides L. ssp. rhamnoides) by high-speed counter-current chromatography (2007) Chromatographia, 65 (1-2), pp. 1-7. Abstract High-speed counter-current chromatography (HSCCC) -a support free all liquid-liquid chromatography technique -has been successfully used for the preparative isolation of isorhamnetin 3-O-ß-D-glucoside, isorhamnetin 3-O-ß-rutinoside, quercetin 3-O-ß-Dglucoside, syringetin 3-O-ß-D-glucoside and protocatechuic acid from sea buckthorn juice concentrate (Hippophaë rhamnoides L. ssp. rhamnoides, Elaeagnaceae). The preparative HSCCC instrument was a multilayer coil planet centrifuge equipped with three preparative coils. Separation was performed with a two phase solvent system (nhexane -n-butanol -water, 1:1:2 v/v/v) in 'head-to-tail' mode. Each injection of 4.1 g crude ethyl acetate extract yielded isorhamnetin 3-O-ß-D-glucoside (95 mg), isorhamnetin 3-O-ß-rutinoside (10 mg), quercetin 3-O-ß-D-glucoside (5 mg), and protocatechuic acid (34 mg) with purities > 98 %. The flavonoid syringetin 3-O-ß-Dglucoside (2 mg) was a novel compound for Hippophaë rhamnoides. Chemical structures of all compounds were determined by HPLC-ESI-MS-MS, 1D-NMR ( 1 H, 1 13 C, DEPT 135) spectroscopy and for elucidation of glycosidic linkages 2D-NMR (HMBC) spectroscopy was used.

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Hydrophilic antioxidant constituents in the fruits of the vegetable Luffa cylindrica (L.) Roem (sponge gourds) were separated by an antioxidant-guided assay to yield eight compounds: p-coumaric acid (1), 1-O-feruloyl-beta-D-glucose (2), 1-O-p-coumaroyl-beta-D-glucose (3), 1-O-caffeoyl-beta-D-glucose (4), 1-O-(4-hydroxybenzoyl)glucose (5), diosmetin-7-O-beta-D-glucuronide methyl ester (6), apigenin-7-O-beta-D-glucuronide methyl ester (7), and luteolin-7-O-beta-D-glucuronide methyl ester (8). The eight compounds were isolated by high-speed countercurrent chromatography and identified by electrospray ionization-mass spectrometry and NMR analysis, and the antioxidant activity was evaluated by the radical scavenging effect on the 1,1-diphenyl-2-picrylhydrazyl radical. High-performance liquid chromatography analysis showed that a total amount of the eight compounds in the dried gourds without skin was about 1%. The results demonstrate that the consumption of sponge gourds can supply some antioxidant constituents to human body.

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