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At least 757 records · Page 42Linked to original sources
PubMed2005

Application of preparative high-speed counter-current chromatography for isolation and separation of schizandrin and gomisin A from Schisandra chinensis.

Following an initial cleaning-up step on the D101 macroporous resin, a preparative high-speed counter-current chromatography (HSCCC) with a two-phase solvent system composed of n-hexane-ethyl acetate-methanol-water (1:0.9:0.9:1, v/v) was used to isolate and separate schizandrin and gomisin A from Schisandra chinensis. A total of 107 mg schizandrin and 36 mg gomisin A with purities of 99.5% and 99.1% were obtained from 400 mg crude extract in one-step elution and less than 3 h, and the structure identification was performed by UV, IR, MS, 1H NMR and 13C NMR.

Chromatography, High Pressure Liquid↗
PubMed2005

Supercritical fluid extraction of aurentiamide acetate from Patrinia villosa Juss and subsequent isolation by silica gel and high-speed counter-current chromatography.

Supercritical fluid extraction (SFE) of aurentiamide acetate from Patrinia villosa Juss was performed. The optimization of parameters was carried out using an analytical-scale supercritical fluid extraction (SFE) system. Then the extraction was scaled up by 100 times using a preparative SFE system under the optimized conditions of 55 degrees C, 35 MPa and modified CO2 with 10% methanol. Then, the crude extract I obtained by SFE was chromatographed on silica gel and the solvent system composed of petroleum ether-ethyl acetate (5:1, v/v) was used to produce the crude extract II, which was further isolated and purified by high-speed counter-current chromatography (HSCCC) with a two-phase solvent system composed of n-hexane-ethyl acetate-methanol-water (1:1.2:1.2:1, v/v/v/v). One hundred fifty-five milligrams of aurentiamide acetate was obtained from 400 mg crude extract II (contained 42% target) with a purity of 99.3% determined by HPLC and 92.3% recovery in one-step elution, and identification was performed by UV, MS, 1H NMR and 13C NMR. As far as we know, this is the first report of discovering aurentiamide acetate from the plant of Patrinia genius.

Acetates↗
PubMed2005

Separation of catechin constituents from five tea cultivars using high-speed counter-current chromatography.

Catechins were extracted from five different tea (Camellia sinensis L.) cultivars. High-speed counter-current chromatography was found to be an efficient method for the separation of seven catechins from the catechin extracts. High-performance liquid chromatography was used to assess the purity of the catechins isolated. Epigallocatechin gallate (EGCG), epicatechin gallate (ECG) and epigallocatechin (EGC) of high purity (91-99%) were isolated in high yield after a single high-speed counter-current chromatography run. The two-phase solvent mixtures used for the separation of the catechin extracts were hexane:ethyl acetate:methanol:water (1:6:1:6 for TRI 2023); (1:7:1:7 for TRI 2025 and TRI 2043); (1:5:1:5 for TRI 3079) and (1:6.5:1:6.5 for TRI 4006). Fresh tea shoots from the tea cultivar TRI 2023 (150 g) gave 440 mg of 96% pure EGCG while TRI 2025 (235 g) gave 347 mg of 99% pure EGCG and 40 mg of 97% ECG, and TRI 3079 (225 g) gave 432 mg of 97% pure EGCG and 32 mg of 96% pure ECG. Tea cultivar TRI 4006 (160 g) gave EGCG (272 mg, 96% pure) and EGC (104 mg, 90% pure). 1H and 13C NMR chemical shifts for catechin gallate (CG), EGC, ECG, EGCG and epigallocatechin 3,5-di-O-gallate (EGCDG) in CD3OD were also recorded.

Camellia sinensis↗
PubMed2005

Preparative isolation and purification of phillyrin from the medicinal plant Forsythia suspensa by high-speed counter-current chromatography.

Forsythia suspensa (Thunb.) Vahl. has been used widely in traditional medicines to treat gonorrhea, erysipelas, inflammation, pyrexia and ulcer. It has also shown antioxidant activity, as well as antibacterial, antiviral, choleretic and antiemetic effects. A high-speed counter-current chromatography (HSCCC) method was developed for the preparative separation and purification of the bioactive molecule phillyrin from F. suspensa (Thunb.) Vahl. The crude phillyrin was obtained by extraction with 50% ethanol from the dried fruits of F. suspensa (Thunb.) Vahl. under sonication. Preparative HSCCC with a two-phase solvent system composed of n-hexane-ethyl acetate-ethanol-water (1:9:1:9, v/v/v/v) was successfully performed, and the components purified and collected were analyzed by high-performance liquid chromatography. The method yielded 5.6 mg phillyrin at 98.6% purity from 500 mg of the crude extract (1.2% phillyrin) with the recovery of 92% in a one-step separation.

Chromatography, High Pressure Liquid↗
PubMed2005

Preparative isolation and purification of two phenylbutenoids from the rhizomes of Zingiber cassumunar by upright counter-current chromatography.

Two phenylbutenoids, (E)-4-(3',4'-dimethoxyphenyl)but-3-enyl acetate and (E)-4-(3',4'-dimethoxyphenyl)but-1,3-diene, were separated from the rhizomes of Zingiber Cassumunar using a preparative upright counter-current chromatography (CCC). With a two-phase solvent system composed of light petroleum (b.p. 60-90 degrees C)-ethanol-diethyl ether-water (5:4:2:1, v/v), 150 mg of (E)-4-(3',4'-dimethoxyphenyl)but-3-enyl acetate and 175 mg of (E)-4-(3','-dimethoxyphenyl)but- 1,3-diene with the purity of 98.7 and 95.1%, respectively, were obtained from 600 mg of the crude sample of Z. Cassumunar in a single-step separation. Structures of these two compounds were identified by ESI-MS, 1H NMR and 13C NMR.

Acetates↗
PubMed2005

Isolation of a novel flavanone 6-glucoside from the flowers of Carthamus tinctorium (Honghua) by high-speed counter-current chromatography.

A novel flavanone glycoside, (2S)-4',5,6,7-tetrahydroxyflavavone 6-O-beta-D-glucopyranoside was isolated from the ethyl acetate extract of the flowers of Carthamus tinctorium by high-speed counter-current chromatography (HSCCC). Using an optimized two-phase solvent system composed of ethyl acetate-methanol-water (5:1:5, v/v), target compound (52 mg) with purity of 98.0% was obtained from 2.0 g of sample by HSCCC in seven times run. The structure of the target compound was elucidated by means of spectroscopic methods including IR, MS, 1D and 2D NMR techniques.

Carthamus↗
PubMed2005

Preparative isolation and purification of polymethoxylated flavones from Tangerine peel using high-speed counter-current chromatography.

Several polymethoxylated flavones including nobiletin, 3,5,6,7,8,3',4'-heptamethoxyflavone, tangeretin and 5-hydroxy-6,7,8,3',4'-pentamethoxyflavone were separated from Tangerine peel (Juhong in Chinese) by high-speed counter-current chromatography (HSCCC) with a two-phase solvent system composed of n-hexane-ethyl acetate-methanol-water (1:0.8:1:1, v/v). Then, 26 mg of nobiletin, 6 mg of 3,5,6,7,8,3',4'-heptamethoxyflavone, 35 mg of tangeretin and 11 mg of 5-hydroxy-6,7,8,3',4'-pentamethoxyflavone could be obtained from 150 mg crude extracts and their purities were 98.6%, 95.9%, 99.8% and 96.8%, respectively. All these constituents were identified by EI-MS and 1H NMR.

Citrus↗
PubMed2005

Isolation and purification of flavonoid glycosides from Trollius ledebouri using high-speed counter-current chromatography by stepwise increasing the flow-rate of the mobile phase.

Three flavonoid glycosides including orientin, vitexin, quercetin-3-O-neohesperidoside and one unknown compound were isolated and purified by high-speed counter-current chromatography (HSCCC) and semi-preparative HPLC from Trollius ledebouri Reichb., a traditional Chinese medicine. Preparative HSCCC with a two-phase solvent system composed of ethyl acetate-n-butanol-water (2:1:3, v/v/v) was successfully performed by increasing the flow-rate of the mobile phase from 1.5 to 2.5 ml/min after 190 min. Consequently, 95.8 mg orientin, 11.6 mg vitexin, 9.3 mg unknown compound with purities of over 97% and one partially purified peak fraction (contained quercetin-3-O-neohesperidoside at 85.1% purity) were obtained from 500 mg of the crude extract. Then the partially purified fraction was further purified by reversed-phase semi-preparative high-performance liquid chromatography. The structure identification of all pure fractions was carried out by UV, MS, 1H NMR and 13C NMR.

Countercurrent Distribution↗
PubMed2005

Isolation and purification of clemastanin B and indigoticoside A from Radix Isatidis by high-speed counter-current chromatography.

A preparative high-speed counter-current chromatography (HSCCC) with a two-phase solvent system composed of ethyl acetate-n-butanol-water (2:7:9, v/v/v) was successfully performed to isolate and separate clemastanin B and indigoticoside A from the plant of Radix Isatidis, a traditional Chinese medicine. A total of 59.2 mg clemastanin B and 66.1 mg indigoticoside A with purities of 94.6% and 99.0% determined by high performance liquid chromatography (HPLC) were obtained in one-step elution from 250 mg crude extract, which contained clemastanin B 24.8% and indigoticoside A 28.4%, and the recoveries of clemastanin B and indigoticoside A were 90.3% and 92.2%, respectively. The chemical structure was identified by IR, MS, 1H NMR and 13C NMR.

Chromatography, High Pressure Liquid↗
PubMed2005

Preparative isolation and separation of a novel and two known flavonoids from Patrinia villosa Juss by high-speed counter-current chromatography.

Preparative high-speed counter-current chromatography (HSCCC) was successfully used for isolation and separation three flavonoids including bolusanthol B, a novel compound named 5,7,2',6'-tetrahydroxy-6,8-di(gamma,gamma-dimethylallyl) flavanone and tetrapterol I from Patrinia villosa Juss using two-phase solvent system composed of n-hexane-ethyl acetate-methanol-water at the volume ratio of 10:11:11:8 (v/v). A total of 25.4 mg bolusanthol B, 52.5 mg 5,7,2',6'-tetrahydroxy-6,8-di(gamma,gamma-dimethylallyl) flavanone and 50.2 mg tetrapterol I were obtained from 250 mg crude extract with purities of 96.8%, 99.2% and 99.3%, respectively determined by HPLC in one single operation and less than 5 h. The structure identification was performed by UV, IR, MS, 1H NMR, 13C NMR and 2D NMR. Among then, bolusanthol B and tetrapterol I were obtained from the plant of Patrinia genius for the first time, and 5,7,2',6'-tetrahydroxy-6,8-di(gamma,gamma-dimethylallyl) flavanone was a novel prenylated flavonoid and discovered from nature for the first time.

Countercurrent Distribution↗
PubMed2005

Preparative isolation and purification of five compounds from the Chinese medicinal herb Polygonum cuspidatum Sieb. et Zucc by high-speed counter-current chromatography.

High-speed counter-current chromatography (HSCCC) was applied to the separation and purification of five compounds from the Chinese medicinal herb Polygonum cuspidatum Sieb. et Zucc. The crude extracts from P. cuspidatum Sieb. et Zucc were treated with light petroleum-ethyl acetate-methanol-water (2:5:4:6, v/v). Sample 1 was obtained from the lower phase and sample 2 from the upper phase. The sample 1 was separated with light petroleum-ethyl acetate-water (1:5:5, v/v) and yielded 19.3mg of piceid, 17.6 mg of anthraglycoside B from 200mg of sample 1. The sample 2 was separated with light petroleum-ethyl acetate-methanol-water (3:5:4:6, v/v) and light petroleum-ethyl acetate-methanol-water (3:5:7:3, v/v) in a gradient elution and yielded 18.5mg of resveratrol, 35.3mg of emodin and 8.2mg of physcion from 220 mg of sample 2. The purity of each compound is over 95% as determined by HPLC. The chemical structures of these components were identified by (1)H NMR and (13)C NMR.

Anthracenes↗
PubMed2005

Preparative isolation and purification of trans-3,5,4'-trihydroxystilbene-4'-O-beta-D-glucopyranoside and (+)catechin from Rheum tanguticum Maxim. ex Balf. using high-speed counter-current chromatography by stepwise elution and stepwise increasing the flow-rate of the mobile phase.

Preparative high-speed counter-current chromatography (HSCCC) was successfully used for isolation and purification of trans-3,5,4'-trihydroxystilbene-4'-O-beta-D-glucopyranoside (compound 1) and (+)catechin (compound 2) from Rheum tanguticum Maxim. ex Balf. by stepwise elution with a pair of two-phase solvent system composed of ethyl acetate-ethanol-water (25:1:25, v/v) and (5:1:5, v/v), and stepwise increasing the flow-rate of the mobile phase from 0.8 to 2.0 mlmin(-1) after 5 h. The preparative HSCCC separation was performed on 250 mg of crude extract yielding pure compound 1 (10.2 mg) and compound 2 (26.7 mg) all at purities of over 96% in a single run. The structures of the two compounds have been elucidated by means of spectroscopic methods including MS and 1H, 13C nuclear magnetic resonance spectroscopy.

Catechin↗
PubMed2005

Large-scale isolation and purification of geniposide from the fruit of Gardenia jasminoides Ellis by high-speed counter-current chromatography.

High-speed counter-current chromatography (HSCCC) was applied to the isolation and purification of geniposide from Gardenia jasminoides Ellis. Analytical HSCCC was used for the preliminary selection of a suitable solvent system composed of ethyl acetate-n-butanol-water (2:1:3, v/v/v). According to the above solvent system, preparative HSCCC was successfully performed with the optimal solvent system composed of ethyl acetate-n-butanol-water (2:1.5:3, v/v/v) yielding 389 mg of geniposide at over 98% purity from 1g of the partially purified extract with 38.9% recovery in a one-step separation.

Countercurrent Distribution↗
PubMed2005

Analytical separation of tea catechins and food-related polyphenols by high-speed counter-current chromatography.

High-speed counter-current chromatography (HSCCC) using the type-J coil planet centrifuge was applied to compositional analysis of tea catechins and separation of other food-related polyphenols. The HSCCC separation of nine different standard compounds and those from extracts of commercial tea leaves was performed with a two-phase solvent system composed of tert-butyl methyl ether-acetonitrile-0.1% aqueous trifluoroacetic acid (TFA) (2:2:3, v/v/v) by eluting the upper organic phase at a flow rate of 2 ml/min. The main compounds in the extract of non-fermented green tea were found to be monomeric catechins, their galloylated esters and caffeine. In addition to these compounds, oxidized pigments, such as hydrophobic theaflavins (TFs) and polar thearubigins (TRs) were also separated and detected from the extracts of semi-fermented oolong tea and fermented black tea. Furthermore, several food-related polyphenols, such as condensed catechin oligomers (procyanidins), phenolic acids and flavonol glycosides were clearly separated under the same HSCCC condition. These separation profiles of HSCCC provide useful information about the hydrophobic diversity of these bioactive polyphenols present in various types of teas and food products.

Biflavonoids↗
PubMed2005

Lutein in selected Canadian crops and agri-food processing by-products and purification by high-speed counter-current chromatography.

This study mainly focused on lutein content in several selected crops grown in southern Ontario, Canada. Marigold flower, a good rotation crop for the control of nematodes in tobacco fields was found to contain 0.77% lutein (after saponification, on dry basis). A high-speed counter-current chromatography (HSCCC) method using a two-phase solvent system consisting of hexane-ethanol-water (6:4.5:1.5, v/v/v) was developed for the purification of lutein from the saponification mixture of marigold flower extract. The purity of lutein prepared using this HSCCC method was 97%. Free lutein was found to be the predominant form in three squash varieties, and it was mostly found in the peel rather than the commonly consumed flesh. Sweet Mamma, Buttercup and Pepper squash varieties contained 25.4, 18.4 and 30.1mg/100g fresh weigh (FW) of lutein in the peels, respectively. These concentrations were significantly higher than that in spinach and kale (3.7 and 12.3 mg/100 g FW). beta-Carotene was found most in the peel of Sweet Mamma squash at 13.6 mg/100g FW, whereas it was below 2mg/100g FW in all other samples. Cooking increased extractable free lutein by 22-65% in squash peels. Lutein in Yukon Gold potato was at ca. 0.4 mg/100 g FW. Certain Yukon Gold was also found to contain violaxanthin (0.35 mg/100 g FW). Structures of lutein, beta-carotene and violaxanthin were identified by LC-atmospheric pressure chemical ionization MS in positive ion mode, and by comparing the retention time and UV-vis spectral data with standards. Results from this study suggest the selected crops and agri-food industrial processing by-products of these can be a good source of free lutein.

Calendula↗
PubMed2005

Developments in the application of counter-current chromatography to plant analysis.

Counter-current chromatography is a very versatile separation technique which does not require a solid stationary phase. It relies simply on the partition of a sample between the two phases of an immiscible solvent system. Some of the more recent applications of the method to the separation of plant-derived natural products are described here. Crude plant extracts and semi-pure fractions can be chromatographed, with sample loads ranging from milligrams to grams. Aqueous and non-aqueous solvent systems are used and the separation of compounds with a wide range of polarities is possible. The technique is complementary to other chromatographic methods and is compatible with gradient systems. The possibilities for solvent selection are almost limitless but some guidelines for the choice of successful systems are presented.

Chromatography, Thin Layer↗
PubMed2005

Efficient new method for extraction and isolation of three flavonoids from Patrinia villosa Juss. by supercritical fluid extraction and high-speed counter-current chromatography.

Supercritical fluid extraction (SFE) of orotinin, orotinin-5-methyl ether and licoagrochalcone B from Patrinia villosa was performed. The optimization of parameters including pressure, temperature, modifier and sample particle size on yield was carried out using an analytical-scale SFE system. The process was then scaled up by 100 times using a preparative SFE system under the optimized conditions of 25 MPa, 45 degrees C, a sample particle size 40-60 mesh and modified CO2 with 20% methanol. The yield of the preparative SFE was 2.82% (crude extract I) and the combined yield of orotinin, orotinin-5-methyl ether and licoagrochalcone B was 0.82 mg/g of dry sample mass. Then the crude extract I was re-dissolved in methanol and methanol soluble fraction (crude extract II, 0.17%) was obtained, which was successfully isolated and separated by a preparative high-speed counter-current chromatography (HSCCC) with a two-phase solvent system composed of n-hexane-ethyl acetate-methanol-water (5:6:6:6, v/v/v/v) by increasing the flow-rate of the mobile phase stepwise from 1.0 to 2.0 ml/min after 3 h. The target compounds isolated and purified by HSCCC were analyzed by high performance liquid chromatography. The separation produced total of 38.2 mg of orotinin at 99.2% purity, 19.8 mg of orotinin-5-methyl ether at 98.5% purity and 21.5 mg of licoagrochalcone B at 97.6% purity from 400 mg of the crude extract in a one-step separation. The recoveries of orotinin, orotinin-5-methyl ether and licoagrochalcone B were 91.1, 91.6 and 90.3%, respectively, and the chemical structure identification was carried out by UV, IR, MS, 1H NMR and 13C NMR.

Chromatography, Supercritical Fluid↗
PubMed2005

A validated higher-performance liquid chromatography method for quantification of cinchonain Ib in bark and phytopharmaceuticals of Trichilia catigua used as Catuaba.

The hydroalcoholic extract, prepared from authentic chopped barks of Trichilia catigua, was evaluated by high-performance liquid chromatography using a diode array detector (200-400 mn). The crude extract was purified by rotation locular counter-current chromatography and the chloroform fraction obtained was clean-up by solid-phase extraction. With the aim of getting preliminary structure information on-line, the methanol fraction thus obtained was analyzed by gradient elution using the diode array detector coupled to a mass spectrometer. The presence of flavalignan in this extract was inferred by the chromatographic band, in the total ion current trace, that had an [M-H](-) = 451. With this information, cinchonain Ib was isolated as a pure compound from the crude hydroalcoholic extract using a solid-phase extraction procedure for the sample clean-up followed by a semi-preparative separation using the reverse mode of elution. The isolated compound, after complete characterization, was used as an external standard for the development and validation of a method for the analysis of this compound in herbal medicines using the ultraviolet as the detector. The validated method has been successfully applied for quantification of cinchonain Ib in commercialized herbal medicines sold as Catuaba in Brazil and also in standard chopped barks of T. catigua.

Catechols↗