Biomedical subjects

Guorong Fan

Publications and source records attributed to Guorong Fan.

At least 19 recordsLinked to original sources

PubMed2006

Development of a liquid chromatography/tandem mass spectrometry assay for the determination of bestatin in rat plasma and its application to a pharmacokinetic study.

Bestatin is a low molecular weight aminopeptidase inhibitor originally isolated from culture filtrates of Streptomyces olivoreticuli. We have developed a sensitive, specific liquid chromatography-tandem mass spectrometry (LC-MS/MS) for the quantitative determination of bestatin in rat plasma using granisetron as the internal standard. The analyte and internal standard were isolated from 50 microL plasma samples by solid phase extraction (SPE). Reverse-phase HPLC separation was accomplished on a Lichrospher C18 column (4.6 mm x 50 mm, 5 microm) with a mobile phase composed of methanol-water-formic acid (70:30:0.5, v/v/v) at a flow rate of 0.8 mL/min. The method had a chromatographic total run time of 3 min. A Varian 1200L electrospray tandem mass spectrometer equipped with an electrospray ionization source was operated in selected reaction monitoring (SRM) mode with the precursor-to-product ion transitions m/z 309.2-->120.0 (bestatin) and 313.4-->138.0 (granisetron) used for quantitation. The method was sensitive with a lower limit of quantitation (LLOQ) of 5 ng/mL, with good linearity (r2 >or= 0.999) over the linear range of 5-2000 ng/mL. All the validation data, such as accuracy, precision, and inter-day repeatability, were within the required limits. The method was successfully applied to pharmacokinetic study of bestatin in rats.

Animals↗

PubMed2006

Orthogonal test design for optimization of supercritical fluid extraction of daphnoretin, 7-methoxy-daphnoretin and 1,5-diphenyl-1-pentanone from Stellera chamaejasme L. and subsequent isolation by high-speed counter-current chromatography.

Supercritical fluid extraction (SFE) of daphnoretin, 7-methoxy-daphnoretin and 1,5-diphenyl-1- pentanone from Stellera chamaejasme L. was performed. An orthogonal L9 (3)4 test design was applied to select the optimum extraction parameters including pressure, temperature, modifier and sample particle size on yield 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 of pressure, 45 degrees C of temperature, 40-60 mesh of sample particle size and modified CO2 with 20% methanol. The yield of the crude extract from preparative SFE was 2.65%, which contained daphnoretin 25.2%, 7-methoxy-daphnoretin 22.8% and 1,5-diphenyl-1-pentanone 21.1%, respectively. Then the crude extract was successfully isolated and separated by preparative high-speed counter-current chromatography (HSCCC) with a two-phase solvent system composed of n-hexane-ethyl acetate-methanol-water (10:13:13:10, v/v) by increasing the flow-rate of the mobile phase stepwise from 1.0 to 2.0 ml/min after 90 min. The target compounds isolated and purified by HSCCC were analyzed by high-performance liquid chromatography (HPLC). The separation produced total of 69.2mg of daphnoretin at 99.2% purity, 63.4 mg of 7-methoxy-daphnoretin at 98.7% purity and 58.3 mg of 1,5-diphenyl-1-pentanone at 98.1% purity from 300 mg of the crude extract in one-step separation. The recoveries of daphnoretin, 7-methoxy-daphnoretin and 1,5-diphenyl-1-pentanone were 90.8, 91.5 and 90.4%, respectively, in HSCCC isolation step and the chemical structure identification was carried out by MS, 1H NMR and 13C NMR.

Chromatography, High Pressure Liquid↗

PubMed2006

Fingerprint analysis of the fruits of Cnidium monnieri extract by high-performance liquid chromatography-diode array detection-electrospray ionization tandem mass spectrometry.

A method incorporating high-performance liquid chromatography (HPLC) with electrospray ionization (ESI) and tandem mass spectrometry (MS), with parallel analysis by HPLC with UV detection using a diode-array detector (DAD) was developed for the qualitative characterization of coumarin and chromone constituents in the fruits of Cnidium monnieri. The chromatographic separations were performed on a Diamonsil C18 column (4.6 mm x 200 mm, 5 microm) with water with 50 mM ammonium acetate and 2% acetic acid (A) and acetonitrile (B) as the mobile phase. According to the characteristic UV spectra, the information of molecular weight and structure provided by ESI-MS/MS, 13 coumarin and 7 chromone components were detected and identified. This method is rapid and reliable for identification of the constituents in the complex herbal system, and the fragmentation patterns proposed could be extended to the similar compounds.

Acetates↗

PubMed2006

Development and validation of a selective and robust LC-MS/MS method for high-throughput quantifying rizatriptan in small plasma samples: application to a clinical pharmacokinetic study.

An analytical method based on liquid chromatography with positive ion electrospray ionization (ESI) coupled to tandem mass spectrometry detection (LC-MS/MS) was developed for the determination of a potent 5-HT(1B/1D) receptor agonist, rizatriptan in human plasma using granisetron as the internal standard. The analyte and internal standard were isolated from 100 microL plasma samples by liquid-liquid extraction (LLE) and chromatographed on a Lichrospher C18 column (4.6mm x 50mm, 5 microm) with a mobile phase consisting of acetonitrile-10mM aqueous ammonium acetate-acetic acid (50:50:0.5, v/v/v) pumped at 1.0 mL/min. The method had a chromatographic total run time of 2 min. A Varian 1200 L electrospray tandem mass spectrometer equipped with an electrospray ionization source was operated in selected reaction monitoring (SRM) mode with the precursor-to-product ion transitions m/z 270-->201 (rizatriptan) and 313.4-->138 (granisetron) used for quantitation. The assay was validated over the concentration range of 0.05-50 ng/mL and was found to have acceptable accuracy, precision, linearity, and selectivity. The mean extraction recovery from spiked plasma samples was above 98%. The intra-day accuracy of the assay was within 12% of nominal and intra-day precision was better than 13% C.V. Following a 10mg dose of the compound administered to human subjects, mean concentrations of rizatriptan ranged from 0.2 to 70.6 ng/mL in plasma samples collected up to 24h after dosing. Inter-day accuracy and precision results for quality control samples run over a 5-day period alongside clinical samples showed mean accuracies of within 12% of nominal and precision better than 9.5% C.V.

Adult↗

PubMed2006

Separation, identification and rapid determination of liensine, isoliensinine and neferine from embryo of the seed of Nelumbo nucifera Gaertn. by liquid chromatography coupled to diode array detector and tandem mass spectrometry.

An application of mass spectrometric methods has been developed to characterize, prepare and quantitatively analyze three bisbenzylisoquinoline alkaloids (liensinine, isoliensinine and neferine) from embryo of the seed of Nelumbo nucifera Gaertn. Initially, an analytical method based on liquid chromatography electrospray ionization tandem mass spectrometry (LC-ESI-MS/MS) with positive ionization mode using a MonoChrom C18 column (4.6 mm x 250 mm i.d. 10 microm) has been developed to characterize liensinine, isoliensinine and neferine, and then scaled up to purify them on a 21.4 mm x 250 mm preparative column. The structures of liensinine, isoliensinine and neferine were elucidated by NMR. Finally, a LC-MS/MS determination method, successfully applied to separation within 3 min, was developed for high throughput simultaneous measurement of liensinine, isoliensinine, and neferine in the extract samples. Multiple reaction monitoring (MRM) was used to monitor the transition of the protonated molecules m/z 611, 611, 625 [M+H]+ to the product ions m/z 206, 192, 206 for analysis of liensinine, isoliensinine and neferine. The LC-MS/MS system was linear in the concentration range of 0.0247-6.02 microg/ml with correlation coefficients of r2>0.992. The quantitative method was validated, with an S/N=3 detection limit of 0.15 ng for liensinine, 0.19 ng for isoliensinine and 0.1 2ng for neferine. The mass fractions of liensinine, isoliensinine, and neferine in the crude extract and the phenolic alkaloid sample of embryo of the seed of N. nucifera Gaertn. were 16.5+/-1.1 and 228.6+/-11.9 for liensinine (mg/g), 45.7+/-1.8 and 640.7+/-15.2 for isoliensinine (mg/g), 59.7+/-6.4 and 58.8+/-9.8 for neferine (mg/g).

Alkaloids↗

PubMed2006

Rapid determination of granisetron in human plasma by liquid chromatography coupled to tandem mass spectrometry and its application to bioequivalence study.

A simple, sensitive and rapid method for analysis of granisetron in human plasma, utilizing liquid chromatography tandem mass spectrometry (LC-MS/MS), has been developed and validated to satisfy FDA guidelines for bioanalytical methods. The analyte and internal standard (IS) were isolated from 100microl plasma samples by liquid-liquid extraction (LLE). A Varian 1200l tandem mass spectrometer equipped with an electrospray ionization source was operated in selected reaction monitoring (SRM) mode with the precursor-to-product ion transitions m/z 313.4/138 for granisetron and m/z 270/201 for the IS used for quantitation. The assay exhibited a linear dynamic range of 0.02-20ng/ml for granisetron in human plasma. The lower limit of quantification (LLOQ) was 0.02ng/ml with a relative standard deviation of less than 15%. The mean extraction recovery from spiked plasma samples was 97.9%. The intra-day accuracy of the assay was within 10% of nominal and intra-day precision was better than 15% C.V. A run time of 2.0min for each sample made it possible for high-throughput bioanalysis. The method was employed in a bioequivalence study of two formulations of granisetron hydrochloride 1mg rapidly disintegrating tablets/1mg capsules.

Administration, Oral↗

PubMed2006

Application of high-speed counter-current chromatography coupled with high-performance liquid chromatography-diode array detection for the preparative isolation and purification of hyperoside from Hypericum perforatum with online purity monitoring.

Following preparative isolation and purification by high-speed counter-current chromatography (HSCCC), the collected fractions were generally analyzed by high-performance liquid chromatography (HPLC) to determine the relative purities of each fraction. Our paper reports for the first time a preparative isolation-purity detection hyphenated system: online coupling of HSCCC with high-performance liquid chromatography-diode array detection (HSCCC-HPLC-DAD). The introduction of online purity analysis in HSCCC has dramatically improved the efficiency of this technique by overcoming the drawbacks of post analysis in HSCCC isolation. The effluent from the outlet of HSCCC was splitted into two parts: one was collected, while the other was introduced directly into an HPLC-DAD system for purity analysis through a switch valve. Therefore, the purities of the obtained fractions from HSCCC were monitored, and fractions with high purities were collected. This strategy has been successfully demonstrated with the preparative isolation and purification of hyperoside from Hypericum perforatum (St. Jone's Wort); a model of TBE-300A HSCCC was used to isolate and separate hyperoside from H. perforatum with a two-phase solvent system composed of ethyl acetate-ethanol-water at the volume ratio of 5:1:5 (v/v) using online detection technique. The isolation was done in less than 3.5 h, and a total of 83.0-mg hyperoside at over 99.0% purity was yielded from 300 mg of the partially purified extract. This new strategy possesses general utility in the preparation of bioactive compounds from traditional Chinese medicine (TCM).

Chromatography, High Pressure Liquid↗

PubMed2006

Quantitative determination of MCC-555, a novel insulin sensitizer in beagle dog plasma by high-performance liquid chromatography with fluorescence detection.

A sensitive high-performance liquid chromatographic method with fluorescence detection has been developed for determination of MCC-555 (5-[[6-(2-fluorbenzyl)-oxy-2-naphy] methyl]-2,4-thiazolidinedione) in beagle dog plasma. Sample preparation was done by protein precipitation with acetonitrile and a synthetic intermediate of MCC-555 (5-[[6-(2-fluorbenzyl)-oxy-2-naphy] methylene]-2,4-thiazolidinedione) was used as the internal standard (IS). The isocratic mobile phase consisted of acetonitrile-10 mmol/l sodium phosphate buffer (pH 4.5) (65:35, v/v) was delivered at a flow rate of 1 ml/min to a Kromasil C(18) reversed-phase column (250 mm x 4.6 mm, 5 microm). The compounds were detected by fluorescence detection, using an excitation wavelength of 232 nm, and emission wavelength of 352 nm. Calibration curves of MCC-555 were linear in the concentration range of 0.005-2.0 microg/ml. Intra- and inter-day precision ranged from 3.4 to 5.4% and 3.0 to 8.8%, respectively. No endogenous interferences were observed with either MCC-555 or IS. The assay is simple, economical, precise, and is directly applicable to pharmacokinetic studies in beagle dogs involving three dose administrations.

Animals↗

PubMed2006

Preparative isolation of four new and two known flavonoids from the leaf of Patrinia villosa Juss. by counter-current chromatography and evaluation of their anticancer activities in vitro.

A preparative counter-current chromatography (CCC) was used to isolate and separate chemical constituents from the leaf of Patrinia villosa, a famous traditional Chinese medicinal herb. Six flavonoids including two known and four novel compounds were successfully simultaneous purified by CCC with a two-phase solvent system composed of n-hexane-ethyl acetate-methanol-water (10: 13: 13: 10, v/v) by increasing the flow rate of the mobile phase from 1.0 ml/min to 2.0 ml/min after 110 min to bring out the late eluters. The separation produced total of 44.9 mg fraction I with 99.1% purity, 35.5 mg fraction II with 98.8% purity, 79.8 mg fraction III with 99.3% purity, 45.8 mg fraction IV with 98.8% purity, 39.8 mg fraction V with 98.6% purity and 9.6 mg fraction VI with 97.5% purity from 400 mg crude extract in one single isolation procedure and less than 10 h, and the obtained fractions were all analyzed by high performance liquid chromatography (HPLC). Their chemical structures were elucidated as (2S)-5,7,2',6'-tetrahydroxy-6,8-di (gamma,gamma-dimethylallyl) flavanone (1), (2S)-5,7,2',6'-tetrahydroxy-6-lavandulylated flavanone (2), (2S)-5,7,2',6'-tetrahydroxy-4'-lavandulylated flavanone (3), (2S)-5,2',6'-trihydroxy-2'',2''-dimethylpyrano [5'', 6'': 6, 7] flavanone (4), (2S, 3''S)-5,2',6'-trihydroxy-3''-gamma,gamma-dimethylallyl-2'',2''-dimethyl-3'',4''-dihydropyrano [5'', 6'': 6, 7] flavanone (5) and licoagrochalcone B (6), respectively, by spectrum methods including UV, IR, high resolution (HR)-electrospray ionization (ESI)-MS, 1-dimension (1D) and 2-dimension (2D) NMR techniques. Among them, compounds 2, 3, 4, and 5 were new compounds and discovered from nature for the first time. The recoveries of the six compounds were 91.2%, 91.4%, 92.1%, 90.5%, 90.3% and 89.7%, respectively, in CCC step. Subsequently, their anticancer activities were also examined to inhibit human cancer cells' growth including A549, BEL-7402, SGC-7901, MCF-7, HT-29, K562 and A498 cell lines by MTT method in vitro. The results indicated that the compounds 1, 2 and 3 exhibited high anticancer activities (IC50 < 7 microg/ml), especially to K562 cancer cell (IC50 < 3.1 microg/ml), and the compounds 4, 5 and 6 exhibited weaker inhibition effect (IC50 < 30 microg/ml).

Antineoplastic Agents, Phytogenic↗

PubMed2006

HPLC determination of polydatin in rat biological matrices: application to pharmacokinetic studies.

A reversed-phase high-performance liquid chromatographic (RPHPLC) method has been developed for the determination of polydatin (PD) in rat plasma, bile, urine, feces and tissue homogenates using 2,3,5,4'-tetrahydroxychrysophenine-beta-d-glucoside as an internal standard. The sample pretreatment included deproteinization for plasma samples and a liquid-liquid extraction for bile, urine, feces and tissue homogenates. Separation was obtained on a C18 reversed-phase column with the mobile phase consisting of methanol and water (35:65 v/v). The flow rate was 1 ml/min and the effluent was monitored at 310 nm. The method showed good linearity over the concentration ranges employed for various matrices (r > 0.998). The quantification limits of PD in rat plasma, bile, urine, feces and tissue homogenates were 0.0251, 0.126, 0.025 microg/ml, 0.189 and 0.0378 microg/g, respectively. The accuracy and precision of the method were less than 12.0% for the various matrices. No interferences from endogenous substances were found. The method was successfully applied to study the pharmacokinetics of PD in rats after intravenous administration.

Animals↗

PubMed2006

Brain pharmacokinetics and tissue distribution of tetrahydropalmatine enantiomers in rats after oral administration of the racemate.

Tetrahydropalmatine (THP), a racemic mixture, is a biologically active ingredient isolated from a traditional Chinese herb Rhizoma Corydalis (yanhusuo). The main objective of this study was to determine the brain pharmacokinetics and tissue distribution of THP enantiomers in rats after oral administration of racemic THP (rac-THP). Rats (5 animals/group/per time) were given a single oral dose of rac-THP and killed after different post-treatment times. The concentrations of THP enantiomers in plasma, cortex, cerebellum, diencephalon, brain stem, striatum and hippocampus were measured using a validated chiral high performance liquid chromatographic (HPLC) method coupled with an achiral column. The pharmacokinetic profiles of the two enantiomers in six brain regions were significantly different. The peak concentrations (Cmax) and AUC(0-infinity) values of the (-)-enantiomer were significantly greater than the corresponding values for the (+)-enantiomer while the striatum contained the highest peak concentrations compared with the plasma and other brain regions. The tissue distribution studies also revealed significant differences between the two enantiomers in all tissues except the lung. The highest concentrations of both enantiomers were found in the liver. The (-)/(+)-THP ratios in six brain regions and other tissues were consistent with that observed in plasma indicating that the stereoselective disposition of THP in rat brain and other tissues reflects the situation in plasma.

Administration, Oral↗

PubMed2005

Separation and quantitative analysis of coumarin compounds from Angelica dahurica (Fisch. ex Hoffm) Benth. et Hook. f by pressurized capillary electrochromatography.

A pressurized capillary electrochromatography (pCEC) method with post-column detection cell has been developed for the therapeutically important coumarins from Angelica dahurica extract. The separation of five major coumarins (xanthotoxol, osthenol, imperatorin, oxypeucedanin hydrate, byakangelicin) was optimized with respect to composition of the mobile phase, ionic strength of buffers, pH, and applied voltage. Baseline separation was achieved for the five coumarins in less than 25 min using a mobile phase of methanol-acetonitrile-phosphate buffer (pH 4.8; 15 mM) (22.5:15:62.5, v/v/v). The method showed satisfactory retention time and peak area repeatability with the first use of post-column detection cell in the pCEC instrument. Comparing to capillary high performance liquid chromatography (capillary HPLC) and conventional high performance liquid chromatography (HPLC), higher column efficiency, and shorter analysis time were achieved in pCEC. The five coumarins in the extract samples representing different stages of traditional extraction of A. dahurica were also quantitatively analyzed by pCEC. The calibration curves were linear in the range 37-129, 36-126, 12-41, 88-306, 20-69 microg/ml of the standard solutions containing the five coumarins with correlation coefficients between 0.9976 and 0.9994.

Calibration↗

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

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

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

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

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

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↗