Preparative isolation and purification of psoralen and isopsoralen from Psoralea corylifolia by high-speed counter-current chromatography

Psoralen and isopsoralen were separated from Psoralea corylifolia by high-speed counter-current chromatography (HSCCC). A two-phase solvent system composed of n-hexane-ethyl acetate-methanol-water (5:5:4.5:5.5, v/v) was used for HSCCC separation, and yielded, from 100 mg of crude extract, 39.6 mg of psoralen and 50.8 mg of isopsoralen each at over 99% purity as determined by high performance liquid chromatography (HPLC). The identification of psoralen and isopsoralen were performed with 1H NMR and 13C NMR.     

Preparative isolation and purification of syringin and edgeworoside C from Edgeworthia chrysantha Lindl by high-speed counter-current chromatography

The bioactive compound syringin along with edgeworoside C were separated from the n-butanol extract of the stems and barks of Edgeworthia chrysantha Lindl (E. papyrifera) by high-speed counter-current chromatography (HSCCC) while it was difficult to purify each compound by silica gel column chromatography. Syringin was isolated from this plant for the first time. The two-phase solvent system used was composed of ethyl acetate-ethanol-water at an optimized volume ratio of 15:1:15 (v/v/v). Preparative HSCCC yielded, from 110mg of the partially purified extract, 28mg of syringin and 45 mg edgeworoside C each at over 96% purity by high-performance liquid chromatography analysis. Their structures were identified by electron impact ionization MS, 1H NMR and 13C NMR.     

Preparative isolation and purification of bergapten and imperatorin from the medicinal plant Cnidium monnieri using high-speed counter-current chromatography by stepwise increasing the flow-rate of the mobile phase

A high-speed counter-current chromatography (HSCCC) method was developed for the preparative separation and purification of bergapten and imperatorin from the Chinese medicinal plant Cnidium monnieri (L.) Cusson. The crude extract was obtained by extraction with ethanol from the dried fruits of Cnidium monnieri (L.) Cusson under sonication. Preparative HSCCC with a two-phase solvent system composed of n-hexane-ethyl acetate-ethanol-water (5:5:5:5, v/v/v/v) was successfully performed by increasing the flow-rate of the mobile phase stepwise from 1.0 to 2.0 ml min(-1) after 180 min. The components purified and collected were analyzed by high-performance liquid chromatography. The method yielded 45.8 mg of bergapten at 96.5% purity and 118.3 mg of imperatorin at 98.2% purity from 500 mg of the crude extract in a single run. The recoveries of bergapten and imperatorin were 92.1 and 93.7%, respectively.     

Application of an efficient strategy based on liquid–liquid extraction,high‐speed counter‐current chromatography,and preparative HPLC for the rapid enrichment,separation, and purification of four anthraquinones from Rheum tanguticum

This study presents an efficient strategy based on liquid–liquid extraction, high‐speed counter‐current chromatography, and preparative HPLC for the rapid enrichment, separation, and purification of four anthraquinones from Rheum tanguticum. A new solvent system composed of petroleum ether/ethyl acetate/water (4:2:1, v/v/v) was developed for the liquid–liquid extraction of the crude extract from R. tanguticum. As a result, emodin, aloe‐emodin, physcion, and chrysophanol were greatly enriched in the organic layer. In addition, an efficient method was successfully established to separate and purify the above anthraquinones by high‐speed counter‐current chromatography and preparative HPLC. This study supplies a new alternative method for the rapid enrichment, separation, and purification of emodin, aloe‐emodin, physcione, and chrysophanol.     

Preparative high-speed counter-current chromatography for purification of shikonin from the Chinese medicinal plant Lithospermum erythrorhizon

The bioactive compound shikonin was successfully isolated and purified from the crude extract of the traditional Chinese medicinal plant Lithospermum erythrorhizon Sieb. et Zucc. by preparative high-speed counter-current chromatography (HSCCC). The preparative HSCCC was performed using a two-phase solvent system composed of n-hexane-ethylacetate-ethanol-water (16:14:14:5 (v/v)). A total amount of 19.6 mg of shikonin at 98.9% purity was obtained from 52 mg of the crude extract (containing 38.9% shikonin) with 96.9% recovery. The preparative isolation and purification of shikonin by HSCCC was completed in 200 min in a one-step separation.     

Isolation and purification of oridonin from the whole plant of Isodon rubescens by high-speed counter-current chromatography

Semi-preparative high-speed counter-current chromatography (HSCCC) was successfully used for isolation and purification of oridonin from Isodon rubescens by using a two-phase-solvent system composed of n-hexane-ethyl acetate-methanol-water (2.8:5:2.8:5, v/v/v/v). The targeted compound isolated, collected and purified by HSCCC was analyzed by high performance liquid chromatography (HPLC). A total of 40.6 mg of oridonin with the purity of 73.5% was obtained in less than 100 min from 100 mg of crude Isodon rubescens extract. The chemical structure of the compound was identified by IR, 1H-NMR and 13C-NMR.     

Isolation of three sesquiterpene lactones from the roots of Cichorium glandulosum Boiss. et Huet. by high-speed counter-current chromatography

Because of the skeletal complexity and similarity of the polarity, little research was reported on the isolation of sesquiterpene lactones by high-speed counter-current chromatography (HSCCC). Herein, three sesquiterpene lactones were successfully purified from the ethyl acetate extract of the roots of the traditional Uyghur medicinal plant Cichorium glandulosum Boiss. et Huet. by HSCCC. The separation was performed in two steps with two solvent systems: n-hexane-ethyl acetate-methanol-water (1.5:5:2.75:5, v/v/v/v) and ethyl acetate-methanol-water (20:1:20, v/v/v). From 166 mg of the ethyl acetate extract, 19 mg of lactucopicrin was isolated with the first solvent system and 10 mg of 11beta,13-dihydrolactucin and 16 mg of lactucin were obtained with the second solvent system. All purified compounds were over 94% purity as determined by HPLC analysis, and these chemical structures were confirmed by (1)H NMR and (13)C NMR.     

Preparative separation of rhein from Chinese traditional herb by repeated high-speed counter-current chromatography

High-speed counter-current chromatography (HSCCC) was repeatedly used for isolation and purification of rhein from Rheum officinale Baill (Dahuang) with a two-phase solvent system composed of n-hexane-ethyl acetate-methanol-water (3:7:5:5, v/v), which had been selected by analytical (HSCCC). Using two preparative units of the HSCCC centrifuge, about a 500 mg amount of the crude extract was separated, yielding 6.7 mg of rhein at a high purity of over 97%.     

Preparative isolation and purification of isoflavan and pterocarpan glycosides from Astragalus membranaceus Bge. var. mongholicus (Bge.) Hsiao by high-speed counter-current chromatography

(3R)-(-)-7,2'-Dihydroxy-3',4'-dimethyl isoflavan-7-O-beta-D-glucopyranoside and (6aR, 11aR) 9,10-di-methoxypterocarpan-3-O-beta-D-glucopyranoside were separated from the ethyl acetate extract of the root of Astragalus membranaceus Bge. var. mongholicus (Bge.) Hsiao by high-speed counter-current chromatography (HSCCC). A two-phase system composed of ethyl acetate-ethanol-acetic acid-water (4:1:0.25:5, v/v) was selected by analytical HSCCC. Preparative HSCCC yielded, from 100 mg of the partially purified extract, 50 mg of isoflavan glycoside and 10 mg of pterocarpan glycoside each at over 95% purity by high-performance liquid chromatography (HPLC) analysis. Their structures were identified by MS, 1H NMR and 13C NMR.     

Preparative isolation of osthol and xanthotoxol from Common Cnidium Fruit (Chinese traditional herb) using stepwise elution by high-speed counter-current chromatography

Preparative high-speed counter-current chromatography (HSCCC) was successfully used for isolation and purification of osthol and xanthotoxol from Cnidium monnieri (L.) Cusson (Common Cnidium Fruit) using stepwise elution with a pair of two-phase solvent systems composed of n-hexane-ethyl acetate-methanol-water at (1:1:1:1, v/v), and (5:5:6:4, v/v), which had been selected by analytical high-speed counter-current chromatography. Using a preparative unit of the HSCCC centrifuge, about a 308 mg amount of the crude extract was separated, yielding 88.3 mg of osthol and 19.4 mg of xanthotoxol at a high purity of over 98%.     

高良姜中二苯基庚烷类化合物的高速逆流色谱分离制备

应用高速逆流色谱法(HSCCC)分离纯化了高良姜中3种二苯基庚烷类化合物。以正己烷-乙酸乙酯-甲醇-水(2:3:1.75:1, v/v/v/v)为两相溶剂系统,下相为固定相,上相为流动相,在主机转速为858 r/min、流速1.5 mL/min的条件下,从122.20 mg高良姜石油醚萃取物中经一步HSCCC分离可制备得到5R-羟基-7-(4-羟基-3-甲氧基苯基)-1-苯基-3-庚酮(7.37 mg)、7-(4-羟基-3-甲氧基苯基)-1-苯基-4E-烯-3-庚酮(9.11 mg)和1,7-二苯基-4E-烯-3-庚酮(15.44 mg),经高效液相色谱分析,纯度均大于93%,各化合物的结构由质谱和核磁共振氢谱、碳谱鉴定确证。该方法简便、快速、高效,可用于高良姜中二苯基庚烷类化合物的快速分离制备。     

Purification of coenzyme Q10 from fermentation extract: high-speed counter-current chromatography versus silica gel column chromatography

High-speed counter-current chromatography (HSCCC) is applied to the purification of coenzyme Q(10) (CoQ(10)) for the first time. CoQ(10) was obtained from a fermentation broth extract. A non-aqueous two-phase solvent system composed of heptane-acetonitrile-dichloromethane (12:7:3.5, v/v/v) was selected by analytical HSCCC and used for purification of CoQ(10) from 500 mg of the crude extract. The separation yielded 130 mg of CoQ(10) at an HPLC purity of over 99%. The overall results of the present studies show the advantages of HSCCC over an alternative of silica gel chromatography followed by recrystallization. These advantages extend to higher purity (97.8% versus 93.3%), recovery (88% versus 74.3%) and yield (26.4% versus 23.4%). An effort to avoid the toxic, expensive solvent CH(2)Cl(2) was unsuccessful, but at least its percentage is low in the solvent system.     

Flow rate gradient high-speed counter-current chromatography separation of five diterpenoids from Triperygium wilfordii and scale-up

In this paper, high-speed counter-current chromatography (HSCCC) instruments with different gravitational forces were applied for the separation of bioactive compounds from Triperygium wilfordii Hook.f. The critical parameters including sample concentration, sample volume and flow rate were first optimized on an analytical Mini-DE HSCCC system, and then scaled up to a preparative TBE 300A HSCCC system. Although this scale-up process was performed using different CCC instruments with different centrifuges and gravitational forces, the same resolutions were obtained and the elution time could be predictable. Five diterpenoid compounds and one unknown compound were separated from Triperygium wilfordii Hook.f. by HSCCC with a two-phase solvent system composed of n-hexane-ethyl acetate-methanol-water (HEMW) (3:2:3:2, v/v/v/v). This one-step flow gradient separation produced triptonide (25 mg), isoneotriptophenolide (77 mg), hypolide (83 mg), unknown compound (1 mg), triptophenolide (42 mg), triptonoterpene methyl ether VI (37 mg) from 320 mg crude extract with purities of 98.2%, 96.6%, 98.1%, 95.3%, 95.1%, and 96.5%, respectively. Their purities and structures were identified by high-performance liquid chromatography, mass spectrometry and NMR. This paper demonstrates that analytical CCC plays an important role in optimizing parameters and scale-up process when analytical CCC and preparative CCC are supplied by different manufacturers with different gravitational forces, and the scale-up process from analytical CCC to preparative CCC is still predictable.     

Preparative separation of high-purity cordycepin from Cordyceps militaris(L.) Link by high-speed countercurrent chromatography

A high-speed counter-current chromatography (HSCCC) technique in a preparative scale has been applied to separate and purify cordycepin from the extract of Cordyceps militaris(L.) Link by a one-step separation. A high efficiency of HSCCC separation was achieved on a two-phase solvent system of n-hexane-n-butanol-methanol-water (23:80:30:155, v/v/v/v) by eluting the lower mobile phase at a flow rate of 2 ml/min under a revolution speed of 850 rpm. HSCCC separation of 216.2 mg crude sample (contained cordycepin at 44.7% purity after 732 cation-exchange resin clean-up) yielded 64.8 mg cordycepin with purity of 98.9% and 91.7% recovery. Identification of the target compound was performed by UV, IR, MS, (1)H NMR and (13)C NMR.     

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.     

Preparative isolation and purification of lutein from the microalga chlorella vulgaris by high-speed counter-current chromatography

High-speed counter-current chromatography (HSCCC) was applied to the isolation and purification of lutein from microalgae. Analytical HSCCC was used for the preliminary selection of a suitable solvent system composed of n-hexane-ethanol-water (4:3:1, v/v). Using the above solvent system, preparative HSCCC was successfully performed yielding lutein at 98% purity from 200 mg of the crude extract in a one-step separation.     

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.     

Isolation and purification of macrocyclic components from Penicillium fermentation broth by high‐speed counter‐current chromatography

In this paper, high‐speed counter‐current chromatography (HSCCC), assisted with ESI‐MS, was first successfully applied to the preparative separation of three macrolide antibiotics, brefeldin A (12.6 mg, 99.0%), 7′‐O‐formylbrefeldin A (6.5 mg, 95.0%) and 7′‐O‐acetylbrefeldin A (5.0 mg, 92.3%) from the crude extract of the microbe Penicillium SHZK‐15. Considering the chemical nature and partition coefficient (K) values of the three target compounds, a two‐step HSCCC isolation protocol was developed in order to obtain products with high purity. In the two‐step method, the crude ethyl acetate extract was first fractionated and resulted in two peak fractions by HSCCC using solvent system n‐hexane/ethyl acetate/methanol/water (HEMWat) (3:7:5:5 v/v/v/v), then purified using solvent systems HEMWat (3:5:3:5 v/v/v/v) and HEMWat (7:3:5:5 v/v/v/v) for each fraction. The purities and structures of the isolated compounds were determined by HPLC, X‐ray crystallography, ESI‐MS and NMR. The results demonstrated that HSCCC is a fast and efficient technique for systematic isolation of bioactive compounds from the microbes.     

Isolation and purification of acteoside and isoacteoside from Plantago psyllium L. by high-speed counter-current chromatography

Two isomeric phenylethanoid glycosides, acteoside and isoacteoside were isolated and purified from the seeds of Plantago psyllium L. for the first time by high-speed counter-current chromatography (HSCCC) using a solvent system consisting of ethyl acetate-water (1:1, v:v). By injecting 200 mg of the n-butanol extract of P. psyllium for five consecutive times, the two-step HSCCC procedure yielded a total of 165 mg of acteoside and 17.5 mg of isoacteoside from 978 mg extract. The recovery rates for acteoside and isoacteoside were 90 and 84%, respectively, and the purities were 98 and 94%, respectively. The HSCCC fractions were analyzed by HPLC and the structures were identified by UV, LC-APCI-MS in negative ion mode, and confirmed by NMR experiments.     

Preparative isolation and purification of two benzoxazinoid glucosides from Acanthus ilicifolius L. by high-speed counter-current chromatography

The first preparative separation of two benzoxazinoids, (2R)-2-O-beta-d-glucopyranosyl-2H-1,4-benzoxazin-3(4H)-one (HBOA-Glc) and (2R)-2-O-beta-d-glucopyranosyl-4-hydroxy-2H-1,4-benzoxazin-3(4H)-one (DIBOA-Glc), by means of high-speed counter-current chromatography (HSCCC) from the n-butanol extract of Acanthus ilicifolius L. is presented. The two-phase solvent system containing ethyl acetate-n-butanol-0.5%NH(4)OH (2:3:5, v/v/v, system B) was selected for the one-step HSCCC separation of HBOA-Glc and DIBOA-Glc according to the partition coefficient values (K) for target compounds and the separation factor (alpha) between the two target compounds. In the one-step HSCCC separation using solvent B, from 100mg n-butanol extract of A. ilicifolius, 6.3 mg HBOA-Glc and 6.8 mg DIBOA-Glc were isolated with purities of 90.3% and 80.2%, respectively. In order to obtain the two target compounds with higher purity, a second separation process was developed comprising two steps. In the two-step separation, the sample was first pre-purified by HSCCC using ethyl acetate-n-butanol-water (2:3:5, v/v/v, system A) solvent system and then purified using solvent system B. A 100-mg amount of the n-butanol extracts of A. ilicifolius was separated to yield 5.8 mg of HBOA-Glc and 4.8 mg of DIBOA-Glc with purities of 97.1% and 94.8%, respectively, which were directly used for NMR analyses.