Centrifugal Partition Chromatography Fractions Research Articles

Isolation of Polyphenols from Aqueous Extract of the Halophyte Salicornia ramosissima.

Polyphenols from residual non-food grade Salicornia ramosissima have health-promoting effects in feed, food, or nutraceutical applications. Therefore, the isolation of polyphenols is of interest from a series of environmentally friendly isolation methods with recyclable solvents. The isolation of polyphenols from non-food grade S. ramosissima was investigated using sequential membrane filtration with and without acid pretreatment, liquid-liquid extraction, resin adsorption, and centrifugal partition chromatography (CPC); analyzed by the Folin-Ciocalteu assay for total polyphenols; and finally analyzed using UPLC-TQMS in negative ion-spray mode for detection of 14 polyphenols. Sequential membrane filtration and acid hydrolysis indicated the polyphenols forming complexes with other compounds, retaining the polyphenols in the retentate fraction of large molecular weight cut-off membrane sizes. Conventional liquid-liquid extraction using sequential ethyl acetate and n-butanol showed most polyphenols were extracted, apart from chlorogenic acids, indicating a low isolation efficiency of higher polarity polyphenols. Analysis of the extract after resin adsorption by Amberlite XAD-4 resin showed high efficiency for separation, with 100% of polyphenols adsorbed to the resin after 13 bed volumes and 96.7% eluted from the resin using ethanol. CPC fractionations were performed to fractionate the concentrated extract after resin adsorption. CPC fractionations of the 14 polyphenols were performed using an organic or aqueous phase as a mobile phase. Depending on the mobile phase, different compounds were isolated in a high concentration. Using these easily scalable methods, it was possible to comprehensively study the polyphenols of interest from S. ramosissima and their isolation mechanics. This study will potentially lead the way for the large-scale isolation of polyphenols from S. ramosissima and other complex halophytes. The compounds of the highest concentration after CPC fractionation were isoquercitrin and hyperoside (155.27 mg/g), chlorogenic acid (85.54 mg/g), cryptochlorogenic acid (101.50 mg/g), and protocatechuic acid (398.67 mg/g), and further isolation using CPC could potentially yield novel polyphenol nutraceuticals.

Rapid Chemical Profiling of Filipendula ulmaria Using CPC Fractionation, 2-D Mapping of 13C NMR Data, and High-Resolution LC-MS.

Filipendula ulmaria, commonly known as meadowsweet, is a wild herbaceous flowering plant that is widely distributed in Europe. A range of salicylic acid derivatives and flavonol glycosides have been previously associated with the antirheumatic and diuretic properties of F. ulmaria. In the present work, a hydroalcoholic extract from F. ulmaria aerial parts was extensively profiled using an efficient NMR-based dereplication strategy. The approach involves the fractionation of the crude extract by centrifugal partition chromatography (CPC), 13C NMR analysis of the fractions, 2D-cluster mapping of the entire NMR dataset, and, finally, structure elucidation using a natural metabolite database, validated by 2D NMR data interpretation and liquid chromatography coupled with mass spectrometry. The chemodiversity of the aerial parts was extensive, with 28 compounds unambiguously identified, spanning various biosynthetic classes. The F. ulmaria extract and CPC fractions were screened for their potential to enhance skin epidermal barrier function and skin renewal properties using in vitro assays performed on Normal Human Epidermal Keratinocytes. Fractions containing quercetin, kaempferol glycosides, ursolic acid, pomolic acid, naringenin, β-sitosterol, and Tellimagrandins I and II were found to upregulate genes related to skin barrier function, epidermal renewal, and stress responses. This research is significant as it could provide a natural solution for improving hydration and skin renewal properties.

Isolation of Alkaloids from Sinomenium acutum by Centrifugal Partition Chromatography and Their Ameliorating Effects on Dexamethasone-Induced Atrophy in C2C12 Myotubes

Bioactivity-guided isolation was conducted using centrifugal partition chromatography (CPC) from an extract of Sinomenium acutum rhizome, which has shown promising preventive effects in a dexamethasone-induced C2C12 myotube atrophy model. CPC was operated with a solvent system of n-butanol–acetonitrile–water (10:2:8, v/v/v, containing 0.5% triethylamine) in dual mode (ascending to descending), which provided a high recovery rate (>99%) with a high resolution. Then, the preventive effects of the obtained CPC fractions were examined against dexamethasone-induced atrophy in C2C12 myotubes according to the weight ratios of the obtained fractions. The active fractions were further purified by semi-preparative HPLC that led to obtaining five alkaloids, one lignan glycoside, and one phenylpropanoid glycoside. Among these, at a concentration of 1 nM, sinomenine, magnoflorine, and acutumine could ameliorate dexamethasone-induced myotube atrophy in C2C12 myotubes by 9.3%, 13.8%, and 11.3%, respectively.

Bioactivity-Guided Single-Step Isolation of Stachyspinoside from Sideritis congesta by Centrifugal Partition Chromatography

Sideritis congesta is a plant native to Mediterranean countries. Infusions of this plant are used to treat various diseases. The anti-inflammatory potential of Sideritis species is widely known. However, the anti-inflammatory potential of an aqueous extract of S. congesta has not been investigated yet. In this study, the phytochemical composition and anti-inflammatory potential of different fractions of an aqueous extract from S. congesta using bioactivity guided fractionation via centrifugal partition chromatography (CPC) were determined. A CPC single-step isolation of a flavonoid stachyspinoside 1 from S. congesta is reported. In addition, a CPC fractionation protocol of the crude aqueous extract was developed. Three aqueous fractions (I, II, and III) of S. congesta were obtained, and their anti-inflammatory potential was evaluated with respect to their ability to inhibit the activity of COX-2 and NF-κB in vitro. Fraction I showed the highest COX-2 inhibition activity (92.3% inhibition at 0.1%). Fraction III showed the highest NF-κB inhibition activity (99.9% at 0.1%) among the CPC produced fractions. The structures of 3 compounds of fraction III could be identified and were validated by HPLC-PDA, HRMS, and NMR spectroscopy. Finally, the phenol, saponin, and flavonoid contents were quantified in the most potent CPC fractions (I and III).

Bioassay-Guided Isolation of Two Eudesmane Sesquiterpenes from Lindera strychnifolia Using Centrifugal Partition Chromatography.

In this study, a centrifugal partition chromatography (CPC) separation was applied to identify antioxidant-responsive element (ARE) induction molecules from the crude extract of Lindera strychnifolia roots. CPC was operated with a two-phase solvent system composed of n-hexane-methanol-water (10:8.5:1.5, v/v/v) in dual mode (descending to ascending), which provided a high recovery rate (>95.5%) with high resolution. Then, ARE induction activity of obtained CPC fractions was examined in ARE-transfected HepG2 cells according to the weight ratios of the obtained fractions. The fraction exhibiting ARE-inducing activity was further purified by preparative HPLC that led to isolation of two eudesmane type sesquiterpenes as active compounds. The chemical structures were elucidated as linderolide U (1) and a new sesquiterpene named as linderolide V (2) by spectroscopic data. Further bioactivity test demonstrated that compounds 1 and 2 enhanced ARE activity by 22.4-fold and 7.6-fold, respectively, at 100 μM concentration while 5 μM of sulforaphane induced ARE activity 24.8-fold compared to the control.

Pilot continuous centrifugal liquid-liquid extraction of extra virgin olive oil biophenols and gram-scale recovery of pure oleocanthal, oleacein, MFOA, MFLA and hydroxytyrosol

This study provides an efficient pilot-scale liquid-liquid extraction process for the recovery of total phenolic fraction (TPF) from extra virgin olive oil (EVOO) and the further purification of the major TPF constituents (oleocanthal, oleacein, monoaldehydic form of oleuropein aglycone, monoaldehydic form of ligstroside aglycone and hydroxytyrosol) using successively centrifugal partition chromatography and reversed phase high performance liquid chromatography. Special attention was paid for the selection of the appropriate raw material, which should be rich in the targeted high-value compounds. For the extraction of the selected EVOOs, a green technique based on liquid-liquid partitioning using the biphasic system n-Hept/EVOO/EtOH/H2O 3:2:3:2 v/v was carried out, first on pioneering laboratory-scale annular centrifugal extractor (ACE) and then on pilot device. 240 L from three different EVOOs (3x80 L of each EVOO) were extracted yielding 285 g of TPF in approximately 2 h. The second step of this procedure was the purification of the target compounds. A preparative centrifugal partition chromatography (CPC) process was firstly applied for the initial TPF fractionation using a step gradient elution-extrusion method with a series of 4 biphasic systems composed of n-Hept/EtOAc/EtOH/H2O in ratios 4:1:3:2, 3:2:3:2, 2:3:3:2 and 1:4:3:2 (v/v/v/v). Preparative reversed phase high performance liquid chromatography (prep-RP-HPLC) was then carried out to polish the target compounds from the enriched CPC fractions resulting in purity higher than 97%. In parallel, the above purification analysis led to the isolation of four minor TPF constituents of which three are new natural products (EDA lactone, (1R, 8E)-1-ethoxy-ligstroside aglycon and (1S, 8E)-1-ethoxy-ligstroside aglycon) and one ((9E, 11E)-13-oxotrideca-9,11-diencoic acid) is described for the first time as EVOO constituent.

Rapid isolation of acidic cannabinoids from Cannabis sativa L. using pH-zone-refining centrifugal partition chromatography

This work introduces an effective methodology for the isolation of acidic cannabinoids from fiber-type Cannabis sativa L. Supercritical fluid extraction (SFE) was initially employed to obtain an enriched extract of acidic cannabinoids. Subsequently, fractionation was performed by using centrifugal partition chromatography (CPC) with the pH-zone-refining method. The biphasic solvent system that was selected consisted of n-hexane/ethyl acetate/ethanol/water 8:2:5:5 (v/v/v/v). Trifluoroacetic acid was added as retainer in the organic stationary phase, while triethylamine was used as eluter in the aqueous mobile phase. The most promising CPC fractions containing cannabidiolic acid (CBDA) and cannabidivarinic acid (CBDVA) were further purified by liquid-liquid extraction. Following this procedure, 1.86 g of CBDA (>85%) were recovered from 9 g of extract, with 1.08 g thereof having a purity of more than 95%, as determined by HPLC-PDA analysis. Moreover, 91 mg of CBDVA with greater than 85% purity were obtained. This methodology can be efficiently used for the large-scale purification of CBDA and after minor modifications could be readily adaptable for the isolation of other acidic cannabinoids, based on their ionizable character.

Centrifugal partition chromatography as a fractionation tool for the analysis of lignocellulosic biomass products by liquid chromatography coupled to mass spectrometry

The conversion of lignocellulosic biomass into biofuels and bio-products leads to oxygenated matrices having a wide range of polarities and molecular weights. A complete analytical characterization of these complex mixtures is necessary to improve conversion processes. In this study, an innovative centrifugal partition chromatography (CPC) protocol was developed to fractionate aqueous biomass samples with a MTBE-water solvent system, by mixing elution, displacement and extrusion modes in the same run. This new protocol was validated on model molecules and applied to the water soluble phase of a fast pyrolysis bio-oil. It demonstrated a promising separation with a relevant selectivity on the most significant chemical families of biomass samples: carbohydrates, furans, carboxylic acids and phenols. CPC fractions of the sample were collected and analyzed comprehensively by HPLC-UV/MS (with ESI negative and positive ionization modes). This CPC x LC approach allowed more accurate attributions on the 217 peaks detected. The use of different detection modes gave a complete view of the water soluble phase of a fast pyrolysis bio-oil through 2D maps. Molecular characterization was enhanced by independent information: CPC retention time, LC retention time, UV and MS spectra. Concomitance of these different chemical information is of precious help for unambiguous identification.

Effects of Oligosaccharides Isolated From Pinewood Hot Water Pre-hydrolyzates on Recombinant Cellulases.

Loblolly pine residues have enormous potential to be the raw material for advanced biofuel production due to extensive sources and high cellulose content. Hot water (HW) pretreatment, while being a relatively economical and clean technology for the deconstruction of lignocellulosic biomass, could also inhibit the ensuing enzymatic hydrolysis process because of the production of inhibitors. In this study, we investigated the effect of oligosaccharide fractions purified from HW pre-hydrolyzate of pinewood using centrifugal partition chromatography (CPC) on three recombinant cellulolytic enzymes (E1, CBHI and CBHII), which were expressed in the transgenic corn grain system. The efficiency of recombinant enzymes was measured using either a 4-methylumbelliferyl-β-D-cellobioside (MUC) or a cellulose-dinitrosalicylic acid (DNS) assay system. The results showed that HW pre-hydrolyzate CPC fractions contain phenolics, furans, and monomeric and oligomeric sugars. Among CPC fractions, oligomers composed of xylan, galactan, and mannan were inhibitory to the three recombinant enzymes and to the commercial cellulase cocktail, reducing the enzymatic efficiency to as low as 10%.

Fractionation of UV-B absorbing molecules and of free radical scavenging compounds from Solieria chordalis by using centrifugal partition chromatography

Liquid-liquid chromatography can lead to the isolation of compounds or enrichment of fractions. To investigate the structural characteristics of antioxidants and UV-B absorbing molecules, a preparative centrifugal partition chromatography (CPC) method was developed to prepare enriched bioactive fractions from the red seaweed Solieria chordalis (Gigartinales, Solieriaceae). After a methanolic extraction of dried Solieria chordalis and liquid-liquid separation using ethyl acetate/water (v/v), the ethyl acetate phase was submitted to CPC using Arizona Y of the quaternary solvent system composed of n-heptane/ethyl acetate/methanol/water (19/1/19/1, v/v) in ascending mode. Among the fifteen collected fractions, three fractions gave up to 23.50% of DPPH radical scavenging activity. The CPC fractionation was monitored by HPLC and, four compounds exhibited UV-B absorbing capacity regarding their absorption at 310nm.

An integrated process for the recovery of high added-value compounds from olive oil using solid support free liquid-liquid extraction and chromatography techniques

An integrated extraction and purification process for the direct recovery of high added value compounds from extra virgin olive oil (EVOO) is proposed by using solid support free liquid-liquid extraction and chromatography techniques. Two different extraction methods were developed on a laboratory-scale Centrifugal Partition Extractor (CPE): a sequential strategy consisting of several “extraction-recovery” cycles and a continuous strategy based on stationary phase co-current elution. In both cases, EVOO was used as mobile phase diluted in food grade n-hexane (feed mobile phase) and the required biphasic system was obtained by adding ethanol and water as polar solvents. For the sequential process, 17.5L of feed EVOO containing organic phase (i.e. 7L of EVOO treated) were extracted yielding 9.5g of total phenolic fraction corresponding to a productivity of 5.8g/h/L of CPE column. Regarding the second approach, the co-current process, 2L of the feed oil phase (containing to 0.8L of EVOO) were treated at 100mL/min yielding 1.03g of total phenolic fraction corresponding to a productivity of 8.9g/h/L of CPE column. The total phenolic fraction was then fractionated by using stepwise gradient elution Centrifugal Partition Chromatography (CPC). The biphasic solvent systems were composed of n-hexane, ethyl acetate, ethanol and water in different proportions (X/Y/2/3, v/v). In a single run of 4h on a column with a capacity of 1L, 910mg of oleocanthal, 882mg of oleacein, 104mg of hydroxytyrosol were successfully recovered from 5g of phenolic extract with purities of 85%, 92% and 90%, respectively. CPC fractions were then submitted to orthogonal chromatographic steps (adsorption on silica gel or size exclusion chromatography) leading to the isolation of additional eleven compounds belonging to triterpens, phenolic compounds and secoiridoids. Among them, elenolic acid ethylester was found to be new compound. Thin Layer Chromatography (TLC), Nuclear magnetic Resonance (NMR) and High Performance Liquid Chromatography – Diode Array Detector (HPLC-DAD) were used for monitoring and evaluation purposes throughout the entire procedure.

Extraction, isolation, and aromatase inhibitory evaluation of low-polar ginsenosides from Panax ginseng leaves

A hyphenated accelerated solvent extraction (ASE) technique was elaborately coupled with centrifugal partition chromatography (CPC), ultra-high-performance liquid chromatography (UHPLC), and photo-diode array detector (PDA). This approach was applied to obtain low-polar ginsenoside fractions from the leaves of Panax ginseng. The CPC fractions were isolated and analyzed using the hyphenated technique, and followed by testing and evaluation of their aromatase inhibitory effects. Subsequently, the aromatase inhibition rates of the compositions in the CPC fractions were calculated using a multivariable linear regression model. A biphasic ethyl acetate/n-butanol/ethanol/water solvent system with respective volume ratios of 10:2:2:8 was used for the ASE and CPC separation of 200g of leaves of P. ginseng raw material. The (lower) aqueous phase of the abovementioned solvent system was used as the extraction solvent. The ginsenosides were subjected to ASE, and the extraction solution was pumped into the sample loop and then directly into the CPC column. The CPC fractions were collected and monitored by an online UHPLC/PDA system at 5-min intervals. The aromatase inhibitory activities of CPC fractions were analyzed by a fluorescence method, with mathematical calculations indicating that the inhibition rates of ginsenosides Rk1, Rg5, Rs5, 20R-Rg3, and Rs4 exceeded 50.00%; indicating that the aforementioned chemical compounds have potential for further development. The results were validated by comparison with authentic standards, indicating that the method used in this research was accurate and advantageous for matrix analysis.

Bio-Guided Isolation of Methanol-Soluble Metabolites of Common Spruce (Picea abies) Bark by-Products and Investigation of Their Dermo-Cosmetic Properties.

Common spruce (Picea abies L.) is a fast-growing coniferous tree, widely used in several countries for the production of sawn wood, timber and pulp. During this industrial exploitation, large quantities of barks are generated as waste materials. The aim of this study was the bio-guided investigation and the effective recovery of methanol-soluble metabolites of common spruce bark for the development of new dermo-cosmetic agents. The active methanol extract was initially fractionated by Centrifugal Partition Chromatography (CPC) using a triphasic solvent system in a step-gradient elution mode. All resulting fractions were evaluated for their antibacterial activity, antioxidant activity and their capability to inhibit tyrosinase, elastase and collagenase activity. In parallel, the chemical composition of each fraction was established by combining a 13C-NMR dereplication approach and 2D-NMR analyses. As a result, fourteen secondary metabolites corresponding to stilbene, flavonoid and phenolic acid derivatives were directly identified in the CPC fractions. A high amount (0.93 g) of E-astringin was recovered from 3 g of crude extract in a single 125 min run. E-Astringin significantly induced the tyrosinase activity while E-piceid, taxifolin, and taxifolin-3′-O-glucopyranoside exhibited significant anti-tyrosinase activity. The above compounds showed important anti-collagenase and antimicrobial activities, thus providing new perspectives for potential applications as cosmetic ingredients.

A galloylated dimeric proanthocyanidin from grape seed exhibits dentin biomodification potential

Grape seeds are a rich source of polyphenols, especially proanthocyanidins (PACs), and are also known for the presence of galloylated oligomeric PACs (OPACs). The present study focuses on the phytochemical methodology for grape seed (O)PACs and their potential role as dentin biomodifiers to be used in restorative and reparative dentistry. A new method using centrifugal partition chromatography (CPC) was developed for the preparative separation of the grape seed (O)PACs. Orthogonal phytochemical profiling of the resulting CPC fractions was performed using C18 and diol HPLC, normal phase HPTLC, and IT-TOF MS analysis. A galloylated procyanidin dimer (1) was isolated from a CPC fraction in order to evaluate its potential to enhance dentin bio-mechanical properties. Moreover, it helped to evaluate the impact of the galloyl moiety on the observed bioactivity. Structure elucidation was performed using ESI-MS, 1D and 2D NMR analyses. For the first time, 1H iterative full spin analysis (HiFSA) was performed on this type of molecule, enabling a detailed proton chemical shift and coupling constant assignment. The CPC fractions as well as 1 showed promising results in the dentin stiffness bioassay and indicate that they may be used as dental intervention biomaterial.

Three-step isolation of a new pregnane from Cynanchum marnieranum Rauh (Apocynaceae)

While there is a rich bibliography concerning the phytochemistry of Asian leaf-bearing Cynanchum species, quite limited work has been done about leafless stem succulent Cynanchum species endemic to Madagascar [1]. Hence, we decided to investigate several Cynanchum species, focusing on Cynanchum marnieranum Rauh from the South of Madagascar. The ethanol extract from the dried stems was submitted to liquid/liquid partition followed by solid phase extraction (SPE) of the non-polar phase. The most interesting fraction was further separated by centrifugal partition chromatography (CPC), choosing the quaternary solvent system cyclohexane: ethyl acetate: methanol: water (6:5:6:5). This led to the isolation of a new pregnane glycoside, which was identified by combination of HR-ESI-TOF-MS and 1D and 2D NMR data as 12,20 dibenzoyl-(20S) – pregn-6-ene-3β,5α,8β,12β,14β,17β,20β -heptol 3-O-β-D-oleandropyranosyl (1→4)-β-D-cymaropyranoside, named marnieranoside A (figure 1). The novelty of this structure is based on the double substitution with benzoyl moieties fixed on a Δ6,7 pregnane structure which occurs for the first time in the genus Cynanchum. Indeed, only Δ5,6 pregnanes have been reported from Cynanchum species until now [2]. This CPC fractionation led also to other Δ6,7 pregnane glycosides according to the 1 H NMR data, which could indicate a specific Δ6,7 pregnane biosynthetic pathway in Cynanchum marnieranum.

Characterization of Proanthocyanidin-Rich Dentin Biomodifiers from Plants by Centrifugal Partition Chromatography

Proanthocyanidins (PAs) are one of the large groups of polyphenols, which represent condensed tannins and consist of oligomeric or polymeric flavan-3-ols. While various bioactivities such as anti-oxidant, anti-inflammatory, anti-microbial, and anti-allergic effects have been frequently reported, little is known about their potential as dentin biomodifiers. Cocoa seeds, grape seeds, and cinnamon barks yield PA-rich extracts which unfold this specific activity. This study evaluated these extracts and measured their capacity as natural cross linkers. Forming part of an interdisciplinary project directed toward the development of a clinical preparation with dentin enhancement properties, the polyphenol-rich plant extracts of cocoa seeds, grape seeds, and cinnamon barks were fractionated by centrifugal partition chromatography (CPC) according to the degree of polymerization. The fractions were monitored by thin layer chromatography (TLC), high-performance liquid chromatography (HPLC) with a diol column, and MALDI-TOF. The result showed that CPC fractionation is a suitable analytical tool to evaluate the relationship between dentin cross linking activity and the degree of polymerization of PAs.

Centrifugal Partition Chromatography (CPC) as an Effective Method for Natural Products Purification

Natural products purification has often been a challenging task to many scientists worldwide. Many techniques have been invented and upgraded to make this task easier. This presentation will depict a few examples of natural products purification by using Centrifugal Partition Chromatography (CPC), which demonstrates a fast and effective way of natural products isolation. One example is CPC was applied to fraction F1 (hexane-ethyl acetate, 95:5) of hexane extract from Mesua elegans (Clusiaceae). Two 4-phenylcoumarins; mammea A/BA and mesuagenin C, was obtained from the fraction, with purity of 93.2% and 94.3% in 500 mg injection in multi-dual mode compare to 82.3% and 79.4% in isocratic mode. Another example is the development of a versatile tool for fast screening and rapid detection of bioactive natural products from plant extracts: the on-line coupling of CPC-UV to HPLC-UV-MS, via a six position switching valve. This strategy offers the possibility to get instant HPLC fingerprint of fractions and structural information about separated molecules during the CPC fractionation step. This new approach was applied to the fractionation and purification of xanthones from Garcinia mangostana (Clusiaceae) pericarp. The combined CPC-HPLC-DAD-MS allows the simultaneous fractionation, detection and characterization of sixteen molecules. Ten molecules were identified based on their UV and MS spectra. Furthermore, this method has led to the isolation of α-mangostin and γ-mangostin at 98.0% and 98.5% purity in a very short time.

Separation of xylose oligomers using centrifugal partition chromatography with a butanol–methanol–water system

Xylose oligomers are the intermediate products of xylan depolymerization into xylose monomers. An understanding of xylan depolymerization kinetics is important to improve the conversion of xylan into monomeric xylose and to minimize the formation of inhibitory products, thereby reducing ethanol production costs. The study of xylan depolymerization requires copious amount of xylose oligomers, which are expensive if acquired commercially. Our approach consisted of producing in-house oligomer material. To this end, birchwood xylan was used as the starting material and hydrolyzed in hot water at 200 °C for 60 min with a 4 % solids loading. The mixture of xylose oligomers was subsequently fractionated by a centrifugal partition chromatography (CPC) with a solvent system of butanol:methanol:water in a 5:1:4 volumetric ratio. Operating in an ascending mode, the butanol-rich upper phase (the mobile phase) eluted xylose oligomers from the water-rich stationary phase at a 4.89 mL/min flow rate for a total fractionation time of 300 min. The elution of xylose oligomers occurred between 110 and 280 min. The yields and purities of xylobiose (DP 2), xylotriose (DP 3), xylotetraose (DP 4), and xylopentaose (DP 5) were 21, 10, 14, and 15 mg/g xylan and 95, 90, 89, and 68 %, respectively. The purities of xylose oligomers from this solvent system were higher than those reported previously using tetrahydrofuran:dimethyl sulfoxide:water in a 6:1:3 volumetric ratio. Moreover, the butanol-based solvent system improved overall procedures by facilitating the evaporation of the solvents from the CPC fractions, rendering the purification process more efficient.

New “hyphenated” CPC-HPLC-DAD-MS strategy for simultaneous isolation, analysis and identification of phytochemicals: application to xanthones from Garcinia mangostana

Centrifugal partition chromatography (CPC) coupled online with high-performance liquid chromatography (HPLC) with diode-array detection (DAD) and mass spectrometry (MS) is presented in this work. This strategy offers the possibility to obtain simultaneously CPC fractionation of natural extracts, the HPLC fingerprint of separated fractions and structural information on molecules contained in each fraction. This new approach was applied to the fractionation and purification of xanthones from Garcinia mangostana (Clusiaceae) pericarp. A biphasic solvent system of heptane/ethyl acetate/methanol/water (2:1:2:1, v/v) was used for the CPC separation of 175 mg crude ethanolic extract. The HPLC analysis was conducted with a reversed-phase monolithic column allowing fast and repeatable separation. This combined CPC-HPLC-DAD-MS method led to isolation of 33 mg α-mangostin and 6 mg γ-mangostin at 98% and 98.5% purity, respectively, in 140 min. Furthermore, in the same time a total of 16 other xanthones were detected in the extract, and ten of them were identified on the basis of their UV and MS spectra.

Isolation and identification of antiplasmodial N-alkylamides from Spilanthes acmella flowers using centrifugal partition chromatography and ESI-IT-TOF-MS

The development of new antiplasmodial drugs is of primary importance due to the growing problem of multi-drug resistance of malaria parasites. Spilanthes acmella, a plant traditionally used for the treatment of toothache, was targeted as a lead for its potential antiplasmodial activity. A systematic approach for investigating a suitable centrifugal partition chromatography (CPC) solvent system for N-alkylamides separation was reported. The partition behavior of three N-alkylamides has been studied using several biphasic solvent mixtures in search of an adequate CPC solvent system for this class of compounds. Major N-alkylamides in S. acmella were isolated from a methanolic crude extract of flowers by CPC with the solvent system heptanes–ethyl acetate–methanol–water (3:2:3:2, v/v/v/v). Four N-alkylamides were purified and the structures were illustrated by electrospray ionization-ion trap-time of flight-mass spectrometry (ESI-IT-TOF-MS), 1H nuclear magnetic resonance ( 1H NMR) and 13C nuclear magnetic resonance ( 13C NMR). The CPC fractions, which contained natural mixtures of phytochemicals, demonstrated significantly higher antiplasmodial activity compared to corresponding purified N-alkylamides, thus suggesting that interactions between these N-alkylamides may potentiate antiplasmodial bioactivity.