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Tetrahydropalmatine in Rhizoma corydalis and its preparations were separated and determined with no pretreatment in the buffer solution of 50 mmol/L of sodium acetate in methanol containing 2 mol/L acetic acid.

Supercritical CO 2 fluid extraction (SFE-CO 2 ) was used to extract volatiles from Patrinia Villosa Juss. An orthogonal test L 9 (3) 4 including pressure, temperature, dynamic extraction time and modifier was performed to get the optimal conditions. Extract 1 was obtained by the optimal extraction condition 1: pressure = 35 MPa, T = 45 °C, dynamic extraction time = 2.0 h and V modifier (MeOH) = 0% as guided by the index 1: the free radical scavenging activities in vitro against 1,1-diphenyl-2-picrylhydrazyl (DPPH) and 2,2′-azino-bis(3-ethyl-benzthiazoline-6-sulfonic acid) diammonium salt (ABTS). Extract 2 obtained by the optimal extraction condition 2: pressure = 25 MPa, T = 55 °C, dynamic time = 2.5 h and V modifier (MeOH) = 20% was guided by the index 2: the yield of the volatiles. The results showed that extract 1 possessed stronger antioxidant activity (EC 50 = 32.01 μg/ml to DPPH and 50.90 μg/ml to ABTS + ) than the extract 2 (EC 50 = 95.62 μg/ml to DPPH and 99.78 μg/ml to ABTS + ). Subsequently, the chemical compositions of the two extracts were identified by gas chromatography–mass spectrometry. Forty-six compounds were identified from extract 1, and the total volatile consisted of hydrocarbon (49.65%), aldehyde (16.66%), fatty acid (22.38%), terpene (9.04%) and little alcoholic. From extract 2, 32 compounds were identified, in which hydrocarbon, aldehyde, fatty acid and terpene possessed 58.21%, 5.97%, 13.19% and 21.79%, respectively. This is the first report of using SFE to extract the volatiles from P. Villosa Juss (a wild vegetable and medicine plant) and first time to systematically evaluate the volatiles’ antioxidant activity and chemical composition.

A 96-well protein precipitation, liquid chromatography-tandem mass spectrometry (LC-MS/MS) method has been developed and fully validated for the determination of fudosteine in human plasma. After protein precipitation of the plasma samples (50 microL) by the methanol (150 microL) containing the internal standard (IS), erdosteine, the 96-well plate was vortexed for 5 min and centrifuged for 15 min. The 100 microL supernatant and 100 microL mobile phase were added to another plate and mixed and then the mixture was directly injected into the LC-MS/MS system in the negative ionization mode. The separation was performed on a XB-CN column for 3.0 min per sample using an eluent of methanol-water (60:40, v/v) containing 0.005% formic acid. Multiple reaction monitoring (MRM) using the precursor-product ion transitions m/z 178--91 and m/z 284--91 was performed to quantify fudosteine and erdosteine, respectively. The method was sensitive with a lower limit of quantification (LLOQ) of 0.02 microg mL(-1), with good linearity (r0.999) over the linear range of 0.02-10 microg mL(-1). The within- and between-run precision was less than 5.5% and accuracy ranged from 94.2 to 106.7% for quality control (QC) samples at three concentrations of 0.05, 1 and 8 microg mL(-1). The method was employed in the clinical pharmacokinetic study of fudosteine formulation product after oral administration to healthy volunteers.

The dried flower buds of Magnolia biondii Pamp are one of the most widely used medicinal plants officially listed in the Chinese Pharmacopoeia. A 2-D column-switching system without sample loop trapping, where two columns were switched directly via a six-port two-position switching valve, was successfully applied for the first time to the isolation and purification of five lignans including pinoresinol dimethyl ether, magnolin, epi-magnolin A, fargesin, and demethoxyaschantin from M. biondii Pamp after microwave-assisted extraction. The introduction of the six-port switching valve instead of sample loop assured 100% recovery from the first dimension to the second, and the injection volumes of the second dimension could reach 12 mL. In this mode of operation, the solvent consumption of the 2-D approach was less than 30% that of conventional gradient methods with even larger sample size. The simultaneous operations of the two dimensions allowed the cycle time to be less than 16 min, compared to 90 min in the gradient elution single-dimension mode of operation. All of the five lignans were isolated at high purities of over 99% with approximately 95% recoveries.

A two-dimensional column-switching system without sample loop trapping, where two columns were switched directly via a six-port two-position switching valve, was successfully applied for the first time to the isolation and purification of six iridoid glycosides including geniposide, gardenoside, shanzhiside, scandoside methyl ester, deacetyl-asperulosidic acid methyl ester and genipin-1-β- d -gentiobioside from Gardenia jasminoides Ellis, a plant used in the traditional Chinese medicine. The introduction of the six-port switching valve instead of sample loop assured 100% recovery from the first dimension to the second, and the injection volumes of the second dimension could reach 20 ml. In this mode of operation, the sample size of the two-dimensional approach was more than 1.3 times that of conventional gradient methods with even less solvent consumption. And the simultaneous operations of the two dimensions allowed the cycle time to be less than 19 min, compared with that (90 min) in the gradient elution single-dimension mode of operation. All of the six isolated iridoid glycosides were isolated at high purities of over 99% with approximately 96% recoveries.

An analytical method incorporating high-performance liquid chromatography (HPLC) with MS and UV-detection was developed for the qualitative and quantitative determination of alkaloids in Corydalis yanhusuo. Ten alkaloids, including seven tertiary alkaloids and three quaternary alkaloids, were identified by comparing their retention times, UV and MS spectra with those of authentic compounds. Furthermore, the collision-induced dissociations of the [M+H](+) and [M](+) ions were studied to clarify the MS behavior of the different types of alkaloids. In positive ion electrospray ionization tandem mass spectrometry (ESI-MS) all the tertiary alkaloids yielded prominent [M+H](+) ions and quaternary alkaloids yielded prominent [M](+) ions in the first order mass spectra. Fragments involving losses of H, CH(3), CO, H(2)O and OCH(3) were observed in the MS/MS spectra. In addition, quantification of the 10 alkaloids in Corydalis yanhusuo from methanol and ethyl acetate extract of different origins were performed by this method, which provides a new tool for the assessment of quality of Corydalis yanhusuo preparations. The method provides the best sensitivity and specificity for characterization and quantitative determination of the alkaloids in Corydalis yanhusuo so far.

A high-performance liquid chromatographic method was developed and validated for the determination and pharmacokinetic study of oxypeucedanin hydrate and byak-angelicin after oral administration of Angelica dahurica extracts in mongrel dog plasma. The coumarin components and the internal standard isopsoralen were extracted from plasma samples with the mixture of tert -butyl methyl ether and n -hexane (4:1, v/v). Chromatographic separation was performed on a C 18 column (200 mm × 4.6 mm, 5 μm) with the mobile phase acetonitrile–methanol–water–acetic acid (20:15:65:2, v/v/v/v) at a flow-rate of 1.0 ml/min. Only the peak of oxypeucedanin hydrate and byak-angelicin could be detected in dog plasma after oral administration of ethanol extracts of A. dahurica mainly containing xanthotoxol, osthenol, imperatorin, oxypeucedanin hydrate and byak-angelicin. The calibration curves of oxypeucedanin hydrate and byak-angelicin were linear over a range of 22.08–8830.00 and 6.08–2430.00 ng/ml in dog plasma, respectively. The quantification limit of oxypeucedanin hydrate and byak-angelicin in dog plasma was 22.08 and 6.08 ng/ml, respectively. The intra- and inter-day precision was less than 7.6% and 8.5% and the accuracy was from 91.9% to 106.1%. The lowest absolute recoveries of oxypeucedanin hydrate and byak-angelicin were 85.7% and 87.0%, respectively. The method was successfully applied to the pharmacokinetic studies of oxypeucedanin hydrate and byak-angelicin in dog plasma after oral administration of ethanol extracts from A. dahurica .

An efficient on-line purity monitoring strategy based on on-line coupling of high-speed counter-current chromatography (HSCCC) with high-performance liquid chromatography-diode array detection (HPLC-DAD) was successfully applied for the first time to the isolation and purification of 5-hydroxymethyl-furancarboxaldehyde (5-HMF), mangiferin and neomangiferin from the Chinese medicinal plant Anemarrhena asphodeloides Bunge, a plant used in the traditional Chinese medicine. The introduction of on-line purity monitoring in HSCCC has greatly improved the efficiency of this technique by overcoming the drawbacks of post-purification sample handling in HSCCC isolation. The effluent from the outlet of HSCCC was split into two parts, and one was collected, while the other was introduced directly through a switch valve into a HPLC-DAD system for purity monitoring. Using this method the desired fractions with high purities could be collected. From 600 mg partially purified extract, 165.6 mg neomangiferin and 292.8 mg mangiferin with purities of 98.9 and 99.5%, respectively, were obtained with a two-phase solvent system composed of n-butanol-water (1:1, v/v) by increasing the flow-rate of the mobile phase stepwise from 1.0 to 2.2 ml min(-1) after 210 min. A 17.1mg 5-HMF with purity of 96.6% was also isolated for the first time.

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 μL plasma samples by solid phase extraction (SPE). Reverse-phase HPLC separation was accomplished on a Lichrospher C18 column (4.6 mm × 50 mm, 5 μm) 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 ≥ 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.

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).

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.

Nine compounds including n-dotriacontanoic acid (I), n-dotriacontanol (II), Palmic acid (III), oleanolic acid (IV) aurentiamide acetate (V), daucosterol (VI), beta-sitosterol (VII), 7beta-hydroxysitosterol (VIII) and stigmasterol (IX) were isolated from petroleum ether and chloroform extract of Patrinia villosa Juss. Among them, compounds I, II, V, VIII were obtained from the plant of Patrinia for the first time and compounds VI, VII ,IX were separated from Patrinia villosa Juss for the first time.

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.

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).

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).

This paper presents a microcomputer-based system for mmurement of electrical impedamce cardiography (Wdt) and determi-nation of left ventricular ejection time (QRS in ECG and X point in dz/ dt) during external counterpulsation (ECP) . Five spot electrodes were experimentally arranged to provide the ECG, dzldt and reference signals. The adaptive filler based on the LMS algorithm was used to eliminate the motion artifacts in #dt dur to inflation and deflation during ECP. The results showed that the processed dzldt waveform was satisfactory during ECP and X point was clearly discernible.

To establish a method determinating the artificial bezoar powder in the bezoar powder by near-infrared diffuse reflectance spectrometry.The calibration set and the test set were set up by adding unequal artificial bezoar powder to the bezoar powder (content range: 0% - 100%), collecting the NIR spectrum of the samples. A mathematical model with partial least squares (PLS) was established to predict the test set.The coefficients of determination (R2) is 99.42 and the relative mean prediction error (RMSECV) is 1.93 respectively for the internal cross-validation set obtained. The coefficients of determination (R2) is 99. 9 and the relative mean standard error prediction (RMSEP) is 0.797, respectively for the test set obtained. The correlation coefficient between true and prediction is 0. 9972.This method is reliable and can be used to control the quality of preparations of bezoar powder.

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 °C, 35 MPa and modified CO 2 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, 1 H NMR and 13 C NMR. As far as we know, this is the first report of discovering aurentiamide acetate from the plant of Patrinia genius .

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.

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.

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.

Tetrahydropalmatine (THP) is a biologically active ingredient isolated from a traditional Chinese herb Rhizoma corydalis (yanhusuo). THP is a racemic mixture which contains 50% of the (+) and 50% of (-) enantiomer. The (-) enantiomer accounts for most of the analgesic effects. Plasma concentrations of THP enantiomers were analyzed by chiral high-performance liquid chromatography (HPLC) on a Chiralcel OJ column with quantification by UV at 230 nm. The method was used to determine the pharmacokinetics of THP enantiomers in rats and dogs after oral administration of rac-THP or (-)-THP. The pharmacokinetic profiles of the two enantiomers after dosing with rac-THP were significantly different both in rats and dogs. The mean C(max) and AUC(0-infinity) values in rats were 1.93 +/- 0.36 microg/ml and 6.65 +/- 2.34 microg x h/ml for the (-) enantiomer, and 1.11 +/- 0.25 microg/ml and 2.03 +/- 0.45 microg x h/ml for the (+) enantiomer. The mean C(max) and AUC(0-infinity) in dogs were 1.60 +/- 0.81 microg/ml and 9.88 +/- 2.58 microg x h/ml for the (-) enantiomer, while 0.36 +/- 0.21 microg/ml and 1.22 +/- 0.40 microg x h/ml for the (+) enantiomer. rac-THP at 40 mg/kg and (-)-THP at 20 mg/kg had very similar plasma concentration-time profiles, and C(max), AUC(0-infinity), and t(1/2) of the (-) enantiomer in both rats and dogs, indicating that the two treatments were equivalent with respect to the pharmacokinetic properties of the (-) enantiomer.

To make clear the origin of the traditional Chinese medicine, Wuguteng.The correlation literature was consulted and arranged.There are a few plants using as Wuguteng, such as Fissistigma glaucescens (Hance) Merr. and Marsdenia tenacissima (Roxb.) Wight et Arn. in the records of principle literature. Wuguteng used as a drug was first recorded in "Dian Nan Ben Cao". The views of various persons in past dynasties on the efficacy of Wuguteng are unanimous.The paper has proved that Wuguteng comes from Marsdenia tenacissima of Asclepiadaceae.

Icariin in Chinese traditional medicine was determined by an accurate and simple capillary zone electrophoresis method which used 30 mmol/L of borate solution containing 10% of acetonitrile as running buffer and needed no pretreatment. Copyright © 1999 John Wiley & Sons, Ltd.

A single syringe pump is employed in this report to add modifier (methanol) through a parallel connection device, which can maintain a constant and lasting (at least 6 h) ratio of methanol without any contamination of the pump. The amount of methanol in supercritical CO2 is measured by gas chromatography. Psoralen and isopsoralen are applied as examples to illustrate the elution effect. With a fixed modifier line, the longer the CO2 line, the higher the concentration. Variations in pressure and/or temperature also have some influence upon the methanol ratio. The single-pump parallel device can conveniently alter the property and ratio of the modifier, and is a probable substitute for gradient programming performed by a dual-pump system.

A pressurized capillary electrochromatographic (pCEC) fingerprint of Ginkgo biloba leaf extract was developed on three different types of capillary columns. A commercial column packed with 3-microm particles and an in-house column packed with 5-microm particles were investigated for their performance. Additionally, a monolithic column was included in the fingerprint study as a potential alternative to the conventional packed columns. The effects of experimental parameters, such as the composition of the mobile phase, the concentration and pH of the buffer, and the applied voltage, were studied. Binary mobile phases consisting of acetonitrile and a 5 mM sodium dihydrogen phosphate electrolyte at pH 2.8 were used in gradient elution mode with an applied voltage of 5 kV. Under optimal gradient conditions, at least 45 peaks were observed within 60 min on the commercial packed column, whereas only about 20 peaks were separated on the methacrylate-based monolithic and the in-house packed columns. The commercial column thus clearly outperforms the two other. However, the properties of the monolithic stationary phase still might be adapted (i.e., by changing the polymerization-mixture composition, the porosity, and thus the selectivity of the phase might be changed), which could lead to an improved efficiency.

Automated decision making is still a significant challenge to realize fully autonomous driving. A common method that encoding surrounding vehicles in a grid map is used to describe observation space for decision making algorithm. It preserves vehicles spatial characteristics. But commonly in human driving, distinct position and speed surrounding vehicles contribute differently to make decision. We introduce a spatial attention module to calculate weights for each vehicle and integrate the attention mechanism into Deep Q network to make decision actions. The agent, ego vehicle, is trained in a simulated highway environment. Simulation results show the proposed method can get significant performance gains compared with other deep reinforcement learning methods by using two kinds of metrics.