Simultaneous determination of icariin, naringin and osthole in rat plasma by UPLC-MS/MS and its application for pharmacokinetic study after oral administration of Gushudan capsules.

A rapid, sensitive and selective ultra performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS) method was developed and validated for the simultaneous determination of icariin, naringin and osthole in rat plasma. Plasma samples pretreatment involved a one-step liquid-liquid extraction with a mixture of ethyl acetate-methyl tert-butyl ether (3:1, ν/ν). The separation was performed on an ACQUITY UPLC™ BEH C18 column with a gradient mobile phase system of methanol and water. The detection was performed on a triple quadrupole tandem mass spectrometer equipped with electrospray ionization (ESI) by multiple reactions monitoring (MRM), with the transitions at m/z 513.3→366.8 (icariin), m/z 579.3→150.9 (naringin), m/z 245.1→189.0 (osthole) and m/z 237.1→194.1 (IS), respectively. A good linear response was observed over the concentration ranges of 1.06-424ng/ml, 2.10-525ng/ml and 1.05-1.05×10(3)ng/ml with lower limit of quantification (LLOQ) of 1.06, 2.10 and 1.05ng/ml for icariin, naringin and osthole, respectively. The intra- and inter-day precisions (R.S.D.) were within 14.3%, and the accuracy (R.E.) ranged from -4.1% to 4.6% at three quality control levels. The sensitive and selective method was applied to a pharmacokinetic study of icarrin, naringin and osthole in rats after oral administration of Gushudan capsule.

Metabonomics study of the effects of pretreatment with glycyrrhetinic acid on mesaconitine-induced toxicity in rats.

ETHNOPHARMACOLOGICAL RELEVANCE: Aconitum carmichaelii Debx. (Fuzi), a commonly use traditional Chinese medicine (TCM), has often been used in combination with Rhizoma Glycyrrhizae (Gancao) to reduce its toxicity due to diester diterpenoid alkaloids aconitine, mesaconitine, and hypaconitine. However, the mechanism of detoxication is still unclear. Glycyrrhetinic acid (GA) is the metabolite of glycyrrhizinic acid (GL), the major component of Gancao. In present study, the effect of GA on the changes of metabolic profiles induced by mesaconitine was investigated using NMR-based metabolomic approaches. MATERIALS AND METHODS: Fifteen male Wistar rats were divided into a control group, a group administered mesaconitine alone, and a group administered mesaconitine with one pretreatment with GA. Their urine samples were used for NMR spectroscopic metabolic profiling. Statistical analyses such as orthogonal projections to latent structures-discriminant analysis (OPLS-DA), t-test, hierarchical cluster, and pathway analysis were used to detect the effects of pretreatment with GA on mesaconitine-induced toxicity. RESULTS: The OPLS-DA score plots showed the metabolic profiles of GA-pretreated rats apparently approach to those of normal rats compared to mesaconitine-induced rats. From the t-test and boxplot results, the concentrations of leucine/isoleucine, lactate, acetate, succinate, trimethylamine (TMA), dimethylglycine (DMG), 2-oxo-glutarate, creatinine/creatine, glycine, hippurate, tyrosine and benzoate were significantly changed in metabolic profiles of mesaconitine-induced rats. The disturbed metabolic pathways include amino acid biosynthesis and metabolism. CONCLUSIONS: GA-pretreatment can mitigate the metabolic changes caused by mesaconitine-treatment on rats, indicating that prophylaxis with GA could reduce the toxicity of mesaconitine at the metabolic level.

Kidney tissue targeted metabolic profiling of glucocorticoid-induced osteoporosis and the proposed therapeutic effects of Rhizoma Drynariae studied using UHPLC/MS/MS.

Traditional Chinese medicine and modern science have indicated that there is a close relationship between bone and kidney. In light of this, this project was designed to study the metabolic profiling by UHPLC/MS/MS of glucocorticoid-induced osteoporosis in kidney tissue and the possible therapeutic effects of Rhizoma Drynariae (RD), a classic traditional Chinese medicine, in improving the kidney function and strengthening bone. Twenty-one Wistar rats were divided into three groups: control group (rats before prednisolone inducing), a model group (prednisolone-induced group) and a treatment group (prednisolone-induced rats that were then administered RD ethanol extracts). By using pattern recognition analysis, a significant change in the metabolic profile of kidney tissue samples was observed in the model group and restoration of the profile was observed after the administration of RD ethanol extracts. Some significantly changed biomarkers related to osteoporosis such as sphingolipids (C16 dihydrosphingosine, C18 dihydrosphingosine, C18 phytosphingosine, C20 phytosphingosine), lysophosphatidycholines (C16:0 LPC, C18:0 LPC) and phenylalanine were identified. As a complement to the metabolic profiling of RD in plasma, these biomarkers suggest that kidney damage, cell cytotoxicity and apoptosis exist in osteoporosis rats, which is helpful in further understanding the underlying process of glucocorticoid-induced osetoporosis and the suggested therapeutic effects of RD. The method shows that tissue target metabonomics might provide a powerful tool to further understand the process of disease and the mechanism of therapeutic effect of Chinese medicines.

Simultaneous determination of seven constituents in Si-Ni-San decoction and a compatibility comparison study using HPLC-UV.

A simple and accurate HPLC-UV method was developed for simultaneous determination of seven constituents in Si-Ni-San decoction. Separation was performed on a Hypersil C18 column and detection was set with gradient wavelength at 240 nm (0-26 min) and 210 nm (26-30 min). The mobile phase consisted of 0.03% phosphoric acid in water (v/v), and acetonitrile was used with a flow rate of 1.0 (- 1). This method provides good linearity (r>0.9992), precision (RSD < 1.9%), repeatability (RSD < 2.9%), stability (RSD < 2.9%) and recovery (97.6-102.0%), which has been successfully applied to quantitative determination of the seven constituents in Si-Ni-San decoction and different compatibility groups.

Comparative pharmacokinetic study of four major components after oral administration of pure compounds, herbs and Si-Ni-San to rats.

The pharmacokinetic differences of paeoniflorin, naringin, naringenin and glycyrrhetinic acid (GA) following oral administration of pure compounds, single herbs and Si-Ni-San (SNS) decoction to rats were studied. Blood samples were analyzed with a validated UPLC-MS/MS method. Student's t-test was used for the statistical comparison. The Cmax and AUC0-∞ were 1470±434 ng/mL and 4663±916 ng h/mL for paeoniflorin, 64.29±59.21 ng/mL and 311.8±131.8 ng h/mL for naringin, 244.2±138.8 ng/mL and 4761±3167 ng h/mL for naringenin, and 1183±294 ng/mL and 38 994±14 377 ng h/mL for GA after oral administration of paeoniflorin, naringin and glycyrrhizic acid. The Cmax and AUC0-∞ were 812.6±259.6 ng/mL and 2489±817 ng h/mL for paeoniflorin, 344.3±234.9 ng/mL and 1479±531 ng h/mL for naringin, 981.9±465.4 ng/mL and 12 284±6378 ng h/mL for naringenin, and 3164±742 ng/mL and 78 817±16 707 ng h/mL for GA after oral administration of SNS decoction. There were significant differences between the pharmacokinetic behavior after oral administration of SNS decoction compared with pure components or herbs. The results indicated that some components in the other herbs of SNS had a pharmacokinetic interaction with paeoniflorin, naringin, naringenin and GA.

An integrated plasma and urinary metabonomic study using UHPLC-MS: intervention effects of Epimedium koreanum on 'Kidney-Yang Deficiency syndrome' rats.

A metabonomic strategy based on UHPLC-MS with principal component analysis was developed to investigate the intervention effects of Epimedium koreanum on metabolism characters of 'Kidney-Yang Deficiency syndrome' rats. The rats were injected intraperitoneally hydrocortisone once daily for 15 days to simulate 'Kidney-Yang Deficiency syndrome' and then administered orally E. koreanum extract once daily for the following 15 days. Plasma and urine samples before hydrocortisone injection, on day 15 of hydrocortisone injection and on days 3, 6, 9, 12, 15 exposed to E. koreanum extract were collected. Significant metabolic disorders were observed in 'Kidney-Yang Deficiency syndrome' rats and sixteen potential biomarkers were identified. The disturbed plasma levels of phenylalanine, tryptophan, cholic acid, lysophosphatidylcholines and urinary levels of phenylalanine, hippurate, phenylacetylglycine, N(2)-succinyl-l-ornithine, creatinine, α-ketoglutarate, citrate, phenol sulfate, indoxyl sulfate, cresol sulfate in model rats were gradually restored to normal after administration of E. koreanum extract, which indicated that E. koreanum had time-dependent recovering effects via regulating oxidant-antioxidant balance, amino acid metabolism, lipid metabolism, energy metabolism, and gut microflora. This work highlights that metabonomics is a promising tool for studying the essence of Chinese medicine's syndrome theory and the action mechanism of traditional Chinese medicine, and provides scientific and reasonable information on safety and efficacy of traditional Chinese medicine.

[Effect of phenformin hydrochloride on pharmacokinetics of puerarin in rats].

OBJECTIVE: To study the effect of phenformin hydrochloride that may be illegally added in traditional Chinese medicine preparations on the pharmacokinetics of puerarin in rats. METHOD: Rats were randomly divided into the single pueraria group and the phenformin hydrochloride combined with pueraria group. After oral administration in the two groups, their bloods were sampled at different time points to determine the drug concentration of puerarin in rat blood and calculate pharmacokinetic parameters. RESULT: After oral administration with pueraria extracts and phenformin hydrochloride combined with pueraria extracts, the two groups showed main pharmacokinetic parameters as follows: Cmax were (2.39 +/- 1.01), (1.03 +/- 0.35) mg x L(-1), respectively; Tmax were (0.50 +/- 0.09), (1.5 +/- 0.5) h, respectively; Ke were (0.153 +/- 0.028), (0.172 +/- 0.042) h(-1), respectively; t(1/2) were (4.65 +/- 0.86), (4.20 +/- 0.81) h, respectively; AUC(0-t), were (5.73 +/- 2.60), (5.45 +/- 1.81) mg x h x L(-1), respectively; AUC(0-infinity) were (6.72 +/- 2.89), (6.26 +/- 1.88) mg x h x L(-1), respectively. Compared with the single puerarin group, the Cmax was significantly decreased (P < 0.05) and the Tmax was markedly longer (P < 0.01) than the hydrochloride combined with pueraria group. CONCLUSION: Phenformin hydrochloride can slow down the absorption process of puerarin and change the pharmacokinetic process of puerarin to some extent.

[Study on in vitro and in vivo material base of Sini San by UPLC-PDA-MS/MS].

OBJECTIVE: To analyze chemical constituents of Sini San its migrating components in rat plasma and study its in vitro and in vivo material base using ultra-performance liquid chromatography coupled with photo-diode-array detector and tandem mass spetrometry (UPLC-PDA-MS/MS). METHOD: ACQUITY UPLC BEH C18 column (2.1 mm x 100 mm, 1.7 microm) was adopted, with gradient elution system of water containing 2 mmol x L(-1) ammonium acetate and acetonitrile at flow rate of 0.2 mL x min(-1). The column temperature was maintained at 35 degrees C. The mass spectra were obtained by electrospray ionization source operating in both positive and negative ion mode. Ions were scanned from the m/z 100 to 1 000, and the characteristic ions were schizolysised twice to obtain the secondary MS data. RESULT: Twenty chemical constituents were detected, including paeoniflorin, glycyrrhizic acid, saikosaponins a and naringin. In vivo, there were 8 ingredients directly absorbed into blood after the administration of Sini San decoction, such as paeoniflorin, naringin and hesperidin. Besides, 6 metabolites were also detected, involving glucuronides, sulfate and sulfoglucuronides. CONCLUSION: In vitro and in vivo chemical materials of Sini San decoction is analyzed by UPLC-PDA-MS/MS to reflect in vitro and in vivo material base of Sini San decoction in a comprehensive and rapid manner and provide basis for further study on efficacious material basis of Sini San decoction.

[Metabonomic study on protective effect of ethanol extracts of drynariae rhizoma on osteoporosis in rats urine by using UPLC-MS/MS].

This paper was designed to study metabonomic characters of the osteoporosis induced by high dose of hydrocortisone and the protective effects of Drynariae Rhizoma, which can replenish the kidney and strengthen the bones. A urinary metabonomics method based on ultra-performance liquid chromatography coupled with mass spectrometry (UPLC-MS/MS) was developed. Clear separation of healthy control group, model group and treatment group was achieved by using the principal components analysis (PCA) and 9 significantly changed metabolites were identified as potential biomarkers of osteoporosis. Compared with the health control group, the model group rats showed lower levels of creatinine, citric acid, azelaic acid, hippurate, tryptophan and indoxyl sulfate together with higher levels of phenylalanine, cresol sulfate and phenaceturic acid. These changes in urinary metabolites suggest that the disorders of amino acid metabolism, energy metabolism, gut microflora and anti-oxidative damage are related to osteoporosis induced by high dose of hydrocortisone and the potential effect of Drynariae Rhizoma on all the four metabolic pathways.

UPLC-MS/MS determination of paeoniflorin, naringin, naringenin and glycyrrhetinic acid in rat plasma and its application to a pharmacokinetic study after oral administration of Si-Ni-San decoction.

A UPLC-MS/MS method was developed for the simultaneous determination of paeoniflorin, naringin, naringenin and glycyrrhetinic acid in rat plasma. A Waters BEH C(18) column was used with a gradient mobile phase system of methanol-water containing 2 mM ammonium acetate. The analysis was performed on a positive ionization electrospray mass spectrometer via multiple reaction monitoring (MRM). One-step protein precipitation with acetonitrile was used to extract the analytes from plasma. The limits of quantification were 9.800 ng/ml for paeoniflorin, 5.100 ng/ml for naringin, 5.200 ng/ml for naringenin and 10.60 ng/ml for glycyrrhetinic acid, respectively. The intra- and inter-day precision (relative standard deviation, RSD) ranged 4.9-12% and 2.8-13%, respectively. The accuracy (relative error, RE) was from -7.3% to 7.5% at all quality control (QC) levels. The validated method was applied to a pharmacokinetic study in rats after oral administration of Si-Ni-San decoction.

LC-MS/MS determination and pharmacokinetic study of four lignan components in rat plasma after oral administration of Acanthopanax sessiliflorus extract.

ETHNOPHARMACOLOGICAL RELEVANCE: Acanthopanax sessiliflorus (Rupr. et Maxim.) Seem. is a shrub mainly present in China, Japan and Korea, the root bark of which is considered as one of the sources of Wujiapi and widely used for its various pharmacological effects. AIM OF THE STUDY: A selective and sensitive UPLC-MS/MS method was developed and validated for the determination and pharmacokinetic study of asarinin, sesamin, helioxanthin and savinin in rat plasma. MATERIALS AND METHODS: Sample preparation involved a liquid-liquid extraction of the analytes with methyl tert-butyl ether (MTBE). LC separation was achieved on a UPLC C(18) column at 30°C with a mobile phase consisting of methanol-2 mM ammonium acetate (68:32, v/v). The detection was accomplished by multiple-reaction monitoring (MRM) scanning with electrospray ionization (ESI) source operating in the positive ionization mode. The optimized mass transition ion-pairs (m/z) monitored for asarinin, sesamin, helioxanthin, savinin and IS were 372.2/233.0, 372.2/233.0, 349.1/319.0, 352.9/334.9 and 180.0/109.7, respectively. RESULTS: The current LC-MS/MS assay was validated for linearity, intra-day and inter-day precisions, accuracy, extraction recovery and stability and was suitable for pharmacokinetic studies of the four lignans after oral administration of Acanthopanax sessiliflorus extract. The time to reach the maximum plasma concentration (T(max)) was 2.50±0.15 h for asarinin, 1.94±0.28 for sesamin, 2.22±0.48 h for helioxanthin and 2.83±0.29 h for savinin. The elimination half-time (t(1/2)) of asarinin, sesamin, helioxanthin and savinin was 6.08±1.10, 11.69±0.50, 7.16±0.52 and 6.26±0.57 h, respectively. CONCLUSION: This paper described a simple, sensitive and validated UPLC-MS/MS method for simultaneous determination of four lignans in rat plasma after oral administration of Acanthopanax sessiliflorus extract, and investigated on their pharmacokinetic studies as well.

Simultaneous determination of pimpinellin, isopimpinellin and phellopterin in rat plasma by a validated UPLC-MS/MS and its application to a pharmacokinetic study after administration of Toddalia asiatica extract.

A rapid and selective ultra performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) method was developed for simultaneous determination of three bioactive coumarins of Toddalia asiatica extract including pimpinellin, isopimpinellin and phellopterin in rat plasma for the first time. Phenacetin was used as the internal standard (IS). Plasma samples were extracted by liquid-liquid extraction with methyl tert-butyl ether. The chromatographic separation was carried out on an ACQUITY UPLC™ BEH C18 column with an isocratic mobile phase consisting of methanol-5 mmol/L ammonium acetate (65:35, v/v). The detection was performed on a triple quadrupole tandem mass spectrometer by multiple reaction monitoring (MRM) via electrospray ionization (ESI) source with positive ionization mode. The method was linear for all analytes over investigated range with all correlation coefficients greater than 0.9942. The lower limits of quantification (LLOQ) were 25.0 ng/mL for pimpinellin, 10.0 ng/mL for isopimpinellin and 5.00 ng/mL for phellopterin. The intra- and inter-day precision (RSD%) was within 12% and the accuracy (RE%) ranged from -2.3% to 5.5%. The rapid and sensitive method was fully validated and successfully applied to the pharmacokinetic study of pimpinellin, isopimpinellin and phellopterin in rats following oral administration of Toddalia asiatica extract.

Metabonomic study on the anti-osteoporosis effect of Rhizoma Drynariae and its action mechanism using ultra-performance liquid chromatography-tandem mass spectrometry.

ETHNOPHARMACOLOGICAL RELEVANCE: Rhizoma Drynariae (RD) is an effectively traditional Chinese medicine which is usually used in treating osteoporosis, bone fracture, streptomycin ototoxicity and hyperlipemia. Up to now, studies on pharmacological mechanism of RD mostly focus on cell and gene level, little is known about its metabonomics study. The aim of this study is to establish the rats plasma metabonomic profiles of control, model and treatment group, then to investigate the anti-osteoporosis effect of RD and its action mechanism. METHOD: A total of 21 Wistar rats was divided into three groups: control group, model group and treatment group. The model and treatment rats were injected prednisolone for 12 weeks, at the same time the treatment rats were orally administered RD extract at a therapeutic dose (10g/kg, expressed as the weight of raw material) once daily throughout the experimental period, control group and model group were orally gavaged approximately volume normal saline solution. After 12 weeks, all plasma samples of three groups were collected and their metabolic profiling changes were analyzed by ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). The resulting dataset was analyzed by principal component analysis (PCA) and partial least squares discriminant analysis (PLS-DA). The identification of all potential biomarkers was performed using reference standard by comparing their mass spectra, MS/MS fragmentation and retention time. Furthermore, clinical biochemistry and biomechanics study were also carried out to ensure the success of the osteoporosis model and to investigate the anti-osteoporosis effect of RD. RESULTS: Obvious separation trend between control and model group was found in PCA score plot, the anti-osteoporosis effect of RD can be indicated in PLS-DA score plot among these three groups. Six potential metabolite biomarkers, Lysophosphatidylcholines (C16:0 LPC, C18:0 LPC, C18:1 LPC and C18:2 LPC), tryptophane and phenylalanine, which were proved to be related with osteoporosis, were identified in the rats plasma. Compared with control group, level of all biomarkers increased significantly in model group, while that was much closer to normal in treatment group. CONCLUSION: The anti-osteoporosis effect of RD has been reliably confirmed by the metabonomics method. The osteoporosis might be prevented by RD via intervening antioxidant-oxidation balance, tryptophane metabolism and phenylalanine metabolism in vivo in rats.

Antibacterial polyketides from the jellyfish-derived fungus Paecilomyces variotii.

Four new polyketides (1-4) were isolated from the fungus Paecilomyces variotii, which was derived from the jellyfish Nemopilema nomurai. The planar structures and relative configurations of these polyketides were elucidated on the basis of spectroscopic analyses, including 2D NMR experiments. The compounds showed inhibitory activity against pathogenic bacteria including methicillin-resistant Staphylococcus aureus 3089 and multi-drug-resistant Vibrio parahemolyticus 7001 with MIC values in the range 5-40 µg/mL.

Preparative isolation of alkaloids from Corydalis bungeana Turcz. by high-speed counter-current chromatography using stepwise elution.

High-speed counter-current chromatography (HSCCC) was successfully applied for the preparative separation and purification of alkaloids from Corydalis bungeana Turcz. (Kudiding in Chinese) for the first time. After the measurement of partition coefficient of seven target alkaloids in the nine two-phase solvent systems composed of CHCl(3)-MeOH-(0.1 M; 0.2 M; 0.3 M) HCl (4:1.5:2; 4:2:2; 4:3:2, v/v), CHCl(3)-MeOH-0.2 M HCl (4:2:2, v/v) and CHCl(3)-MeOH-0.3 M HCl (4:3:2, v/v) were finally selected for the HSCCC separation using the first upper phase as the stationary phase and the stepwise elution of the two lower mobile phases. Consequently, sanguinarine (10 mg), corynoline (25 mg), protopine (20 mg), corynoloxine (18 mg), and 12-hydroxycorynoline (8 mg) were obtained from 200 mg of crude alkaloid extracts with purities of 94-99% as determined by HPLC. Their chemical structures were characterized on the basis of (1)H-NMR, (13)C-NMR, and LC-ESI-Q-TOF-MS/MS analyses.

Metabonomic study on 'Kidney-Yang Deficiency syndrome' and intervention effects of Rhizoma Drynariae extracts in rats using ultra performance liquid chromatography coupled with mass spectrometry.

This paper was designed to study metabonomic characters of the 'Kidney-Yang Deficiency syndrome' induced by high dose of hydrocortisone and the therapeutic effects of Rhizoma Drynariae, classic traditional Chinese medicine (TCM) in treating the syndrome. A urinary metabonomics method based on ultra-performance liquid chromatography coupled with mass spectrometry (UPLC/MS) was developed. The significant difference in metabolic profiling was observed from model group (hydrocortisone-induced group) compared with the pre-dose group (rats before hydrocortisone inducing) by using the principal components analysis (PCA). The time-dependent regression tendency in Rhizoma Drynariae treatment group (hydrocortisone-induced rats followed by being administered with Rhizoma Drynariae ethanol extracts) from day 3 to 15 was obtained, indicating the time-dependent recovery effect of Rhizoma Drynariae on 'Kidney-Yang Deficiency syndrome' rats. Some significantly changed metabolites like phenylalanine, phenylacetylglycine, N(2)-succinyl-L-ornithine, L-proline, creatinine, hippurate and citrate have been identified. These biochemical changes are related to the disturbance in energy metabolism, amino acid metabolism and gut microflora, which are helpful to further understand the 'Kidney-Yang Deficiency syndrome' and the therapeutic mechanism of Rhizoma Drynariae. The work shows that the metabonomics method is a valuable tool for studying the essence of Chinese medicine's syndrome theory and therapeutic effect mechanism of TCM.

Determination and pharmacokinetic study of chiisanogenin in rat plasma by ultra performance liquid chromatography-tandem mass spectrometry.

INTRODUCTION: Chiisanogenin existing in many Acanthopanax species has been reported to possess anti-inflammatory, antibacterial and antiplatelet aggregatory activities. OBJECTIVE: To develop and validate a rapid and sensitive ultra performance liquid chromatography-tandem mass spectrometry method for the determination of chiisanogenin in rat plasma and to investigate its pharmacokinetics after oral administration of chiisanogenin or the extract of Acanthopanax sessiliflorus fruits. METHODOLOGY: The sample pretreatment involved a one-step extraction of 0.2 mL plasma with diethyl ether. Acetaminophen was used as the internal standard. The separation was carried out on an ACQUITY UPLC™ BEH C18 column with a mobile phase of acetonitrile-5 mM ammonium acetate (90:10, v/v) at a flow rate of 0.2 mL/min. The detection was performed on a triple quadrupole tandem mass spectrometer by multiple reaction monitoring (MRM) mode via electrospray ionization (ESI) source. RESULTS: A high sample throughput was achieved with an analysis time of 1.1 min per sample. The calibration curve was linear (r² ≥ 0.99) over the concentration range of 5-500 ng/mL with a lower limit of quantification (LLOQ) of 5 ng/mL. The intra-day and inter-day precision (relative standard deviation, R.S.D.) values were below 11% and the accuracy (relative error, R.E.) was within 8% at all three quality control (QC) levels. CONCLUSION: The method was successfully applied to the pharmacokinetic study of chiisanogenin in rat after oral administration of chiisanogenin and the extract of Acanthopanax sessiliflorus fruits. Other constituents in the extract affected the pharmacokinetic behavior of chiisanogenin.

[Studies on chemical constituents of the extract of Lonicera japonica].

OBJECTIVE: To isolate and elucidate the structure of the constituents of the extract of Lonicera japonica. METHODS: The compounds were isolated and repeatedly purified on TLC, silica gel column chromatography, and gel column chromatography. The structures were elucidated by physico-chemical properties, MS and NMR. RESULTS: Seven compounds were obtained and elucidated as luteolin (I), luteoloside (II), quercetin (III), quercetin-3-0-beta-D-glucoside (IV), quercetin-7-0-beta-D-glucoside (V), rutin (VI), chlorogenic acid (VII). CONCLUSION: Compound V is isolated from this genus for the first time.

A rapid and reliable UPLC-MS/MS method for the identification and quantification of fourteen synthetic anti-diabetic drugs in adulterated Chinese proprietary medicines and dietary supplements.

An ultraperformance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) method was developed for simultaneous qualitative and quantitative analysis of 14 synthetic anti-diabetic drugs in adulterated Chinese proprietary medicines (CPMs) and dietary supplements. The samples were prepared by ultrasonic extraction with methanol and separated on a C18 column with mobile phase consisting of acetonitrile and water (both containing 0.10% formic acid). Gradient elution was applied with a flow rate of 0.20 mL/min. Two transitions from protonated molecules were monitored for each synthetic anti-diabetic drug in positive mode of electrospray ionization (ESI). The two transitions, the peak area ratio of the two transitions and the retention time were used for identification. The more intensive transition was used for quantification. The analysis time was 6 min per sample. Satisfactory linear relationships were estimated between the peak area and the concentration with correlation coefficients higher than 0.995. The limit of detection ranged from 0.03 to 5.45 ng/mL. The relative standard deviation of intra-day precision was below 7.6%, the RSD of inter-day precision was below 15% and the relative error of accuracy was between -10 and 7.8%. The proposed method is rapid, selective, reliable and was successfully applied to the analysis of 30 real samples of 22 CPMs and eight dietary supplements from the local market in China.

Simultaneous determination of neoeriocitrin and naringin in rat plasma after oral administration of a Chinese compound formulation by UPLC-MS-MS.

A sensitive, specific method has been developed for simultaneous determination of neoeriocitrin and naringin in rat plasma using liquid chromatography-tandem mass spectrometry. With hesperidin as the internal standard, plasma samples were prepared by protein precipitation with methanol. Analysis was carried out on an ACQUITY UPLC BEH C(18) column using acetonitrile-water (20:80, v/v) as the mobile phase. Detection was performed by means of electrospray ionization mass spectrometry in negative ion mode with multiple reaction monitoring. Linear calibration curves of neoeriocitrin and naringin were obtained over the concentration ranges of 15.0-960 ng/mL and 12.0-1200 ng/mL, respectively. The intra- and inter-day precisions were within 9.7% and 7.6% for neoeriocitrin and 7.8% and 12.9% for naringin. The accuracy was from -4.3% to 0.43% for neoeriocitrin and from -3.8% to 3.0% for naringin. The validated method was successfully applied to the pharmacokinetic study of neoeriocitrin and naringin in rats after oral administration of a Chinese compound formulation, gushudan.