Identification and analysis of absorbed and metabolic components in rat plasma after oral administration of 'Shuangdan' granule by HPLC-DAD-ESI-MS/MS

Optimizing extraction methods by a comprehensive experimental approach and characterizing polyphenol compositions of Ecklonia radiata

Brown seaweed Ecklonia radiata harbors valuable polyphenols, notably phlorotannins, prized for their health benefits. This study optimized phlorotannin extraction via conventional solvent extraction and ultrasound-assisted extraction methods, utilizing variable concentrations of ethanol. Employing fractional factorial designs, key variables were identified. Steepest ascent/descent method and central composite rotatable designs refined optimal conditions, enhancing phlorotannin and polyphenol yields, and antioxidant capacities. Under optimized conditions, phlorotannin contents reached 2.366 ± 0.01 and 2.596 ± 0.04 PGE mg/g, total polyphenol contents peaked at 10.223 ± 0.03 and 10.836 ± 0.02 GAE mg/g. Robust antioxidant activity was observed: DPPH and OH radical scavenging capacities measured 27.891 ± 0.06 and 17.441 ± 0.08 TE mg/g, and 37.498 ± 1.12 and 49.391 ± 0.82 TE mg/g, respectively. Reducing power capacities surged to 9.016 ± 0.02 and 28.110 ± 0.10 TE mg/g. Liquid chromatography-mass spectrometry (LC-MS) and high-performance liquid chromatography (HPLC) analyses revealed enriched antioxidant compounds. Variations in polyphenol profiles were noted, potentially influencing antioxidant capacity nuances. This study illuminated the potential of E. radiata potential as a polyphenol source and offers optimized extraction methods poised to benefit various industries.

Genus Paeonia: A comprehensive review on traditional uses, phytochemistry, pharmacological activities, clinical application, and toxicology

ETHNOPHARMACOLOGICAL RELEVANCE

Paeonia, which comprises approximately 52 shrubs or herbaceous perennials around the world, is the only genus of the Paeoniaceae and is pervasively distributed in Asia, southern Europe, and North America. Many species of the genus Paeonia have been used for centuries in ethnomedical medical systems.

AIM OF THE REVIEW

The present study aims to summarize the traditional uses, clinical applications, and toxicology of the genus Paeonia, to critically evaluate the state-of-the-art phytochemical and pharmacological studies of this genus published between 2011 and 2020, and to suggest directions for further in-depth research on Paeonia medicinal resources.

MATERIALS AND METHODS

Popular and widely used databases such as PubMed, Scopus, Science Direct, and Google Scholar were searched using the various search strings; from these searches, a number of citations related to the traditional uses, phytochemistry, biological activities, clinical application, and toxicology of the genus Paeonia were retrieved.

RESULTS

The use of 21 species, 2 subspecies, and 7 varieties of the genus Paeonia as traditional herbal remedies has been reported, and many ethnomedicinal uses, such as the treatment of hematemesis, blood stasis, dysmenorrhea, amenorrhea, epilepsy, spasms, and gastritis, have been recorded. The roots and root bark are the most frequently reported parts of the plants used in medicinal applications. In phytochemical investigations, 451 compounds have been isolated from Paeonia plants to date, which contains monoterpenoid glucosides, flavonoids, tannins, stilbenes, triterpenoids and steroids, and phenols. Studies of their pharmacological activities have revealed the antioxidant, anti-inflammatory, antitumour, antibacterial, antiviral, cardiovascular protective, and neuroprotective properties of the genus Paeonia. In particular, some bioactive extracts and compounds (total glucosides of peony (TGP), paeonol, and paeoniflorin) have been used as therapeutic drugs or tested in clinical trials. In addition to the "incompatibility" of the combined use of "shaoyao" and Veratrum nigrum L. roots in traditional Chinese medicine theory, Paeonia was considered to have no obvious toxicity based on the available toxicological tests.

CONCLUSION

A large number of phytochemical and pharmacological reports have indicated that Paeonia is an important medicinal herb resource, and some of its traditional uses including the treatment of inflammation and cardiovascular diseases and its use as a neuroprotective agent, have been partially confirmed through modern pharmacological studies. Monoterpenoid glucosides are the main active constituents. Although many compounds have been isolated from Paeonia plants, the biological activities of only a few of these compounds (paeoniflorin, paeonol, and TGP) have been extensively investigated. Some paeoniflorin structural analogues and resveratrol oligomers have been preliminarily studied. With the exception of several species (P. suffruticosa, P. ostii, P. lactiflora, and P. emodi) that are commonly used in folk medicine, many medicinal species within the genus do not receive adequate attention. Conducting phytochemical and pharmacological experiments on these species can provide new clues that may lead to the discovery of medicinal resources. It is necessary to identify the effective phytoconstituents of crude extracts of Paeonia that displayed pharmacological activities by bioactivity-guided isolation. In addition, comprehensive plant quality control, and toxicology and pharmacokinetic studies are needed in the future studies.

Green Synthesis of Silver Nanoparticles Using Extract of Jasminum officinal L. Leaves and Evaluation of Cytotoxic Activity Towards Bladder (5637) and Breast Cancer (MCF-7) Cell Lines

INTRODUCTION

Jasminum officinale L. is a very important medicinal and industrial flowering aromatic plant.

METHODS

The present study deals with Jasminum officinale L. leaves extract (JOLE) as a reducing and capping agent for the synthesis of silver nanoparticles (AgNPs) by the green pathway. Phenolic profile of the extract was evaluated using HPLC-PDA/MS/MS technique. Jasminum officinale L. leaves extract silver nanoparticles (JOLE-AgNPs) were characterized by ultraviolet light (UV), Fourier transform infrared spectroscopy (FTIR), transmission electron microscopy (TEM), zeta potential and X-ray diffraction (XRD). JOLE-AgNPs were examined for their cytotoxic activities by neutral red uptake assay (NRU) against bladder (5637) and breast cancer (MCF-7) cell lines.

RESULTS

HPLC-PDA/MS/MS tentatively identified 51 compounds of different chemical classes. UV spectra showed absorption peak at λmax = 363 nm. The biosynthesized AgNPs were predominantly spherical in shape with an average size of 9.22 nm by TEM. The face cubic center (fcc) nature of silver nanoparticles was proved by XRD diffractogram. JOLE-AgNPs exhibited high cytotoxic activity against 5637 and MCF-7 cell lines compared to the cytotoxic activities of JOLE with IC50 of 13.09 µg/mL and 9.3 µg/mL, respectively.

DISCUSSION

The silver nanoparticles formed by Jasminum officinale L. showed high cytotoxic activities against MCF-7 and 5637 cell lines and can be introduced as a new alternative cytotoxic medication.

Chemistry, pharmacokinetics, pharmacology and recent novel drug delivery systems of paeonol

Paeonol is a bioactive phenol present in Dioscorea japonica, Paeonia suffruticosa and Paeonia lactiflora. It is reported for various pharmacological activities.

AIM

To review chemistry, pharmacokinetics, pharmacological activities as well as various formulations of paeonol.

MATERIALS AND METHODS

A literature search was done using different search terms for paeonol by using different scientific databases like PubMed, Scopus and ProQuest. Scientific papers published during the period 1969 to 2019 were comprehensively reviewed.

KEY FINDINGS

Researchers have synthesized methoxy, ethoxy, piperazine, chromonylthiazolidine, phenol-phenylsulfonyl, alkyl ether, aminothiazole, tryptamine hybrids and paeononlsilatie derivatives to enhance the stability of paeonol. These derivatives were synthesized and evaluated for in vitro series of biological activities like anti-inflammatory, tyrosinase inhibitory, neuroprotective, anticancer and antiviral activity. Regardless of valuable therapeutic potential, the clinical use of paeonol is restricted due to poor water solubility, low oral bioavailability, low stability and high volatility at room temperature. To enhance the bioavailability of paeonol various formulations are prepared and evaluated for its activity. Paeonol formulations can be categorized as conventional-tablets, topical gel and hydrogel; polymeric delivery system-microparticles, microsponges, dendrimers, nanocapsules, polymeric nanoparticles, nanospheres; lipid-based delivery systems-microemulsion, self-micro-emulsifying drug delivery, liposome, transethosomes, ethosomes, niosomes, proniosomes, lipid-based nanoparticles and nanoemulsion of paeonol.

SIGNIFICANCE

Paeonol has a potential to be developed as a techno-commercial product with respect to its multi-faceted pharmacological properties. Even though in vitro and in vivo studies have been reported the important activities of paeonol, its commercial utilization requires extensive safety and efficacy data.

Research progress on classical traditional Chinese medicine formula Liuwei Dihuang pills in the treatment of type 2 diabetes

In traditional Chinese medicine (TCM), type 2 diabetes mellitus (T2DM) is regarded as Xiao Ke disease. Liuwei Dihuang pills (LWP), a classical TCM formula, with the function of nourishing kidney yin, has been used for treating Xiao Ke disease in clinic. In this review, we systematically highlighted recent evidence on LWP and T2DM data from clinical and animal studies, summarized the clinical application, pharmacological mechanism and the active compounds of LWP for the treatment of T2DM. This systematic review will provide an insightful understanding of TCM formulas, pharmacological mechanisms, medicinal-disease interactions, and will lay a foundation for the development of new drug therapy for T2DM.

An Available Strategy for Nasal Brain Transport of Nanocomposite Based on PAMAM Dendrimers via In Situ Gel

Polyamidoamine (PAMAM) dendrimers are efficient drug carriers. The presence of a physiological pathway for nasal brain transport provides a potential path for direct brain-targeted delivery of dendrimer nanocomposites. In this study, we synthesized PAMAM dendrimer composites with a nanoscale size; the particle size of PAE (Paeonol)/mPEG (the heterofunctional PEG polymer with a methoxy)-PAMAM G5.NHAc and mPEG-PAMAM G5.NH₂-FITC were 72.41 ± 11.58 nm and 96.51 ± 7.77 nm, and the zeta potential of PAE/mPEG-PAMAM G5.NHAc and mPEG-PAMAM G5.NH₂-FITC were + 0.57 ± 0.11 mv and + 9.60 ± 0.41 mv, respectively. The EE% and DL% of PAE in PAE/mPEG-PAMAM G5.NHAc were 53.77% and 13.92%, respectively. PAE/mPEG-PAMAM G5.NHAc/DGG ionic-sensitive in situ gel was prepared, the viscosity of solution and gel state were 112 ± 3.2 mPa and 1403 ± 38.5 mPa, respectively. The in vitro goat mucoadhesive strength of the gel was 4763.36 ± 85.39 dyne/cm². In situ gel system was proven to be a non-Newtonian pseudo-plastic fluid with shear thinning, thixotropy and yield stress. The optimal model of PAE released from PAE/mPEG-PAMAM G5.NHAc and PAE/mPEG-PAMAM G5.NHAc/DGG were the Higuchi equation and the Korsmeyer-Peppas equation, respectively. The cytotoxicity of the nanocomposites showed a concentration-dependence, and the cell viabilities of PAE/mPEG-PAMAM G5.NHAc were both higher than 95% between 0.0001 μM and 10 μM. mPEG-PAMAM G5.NH₂-FITC was efficiently taken up by cells and exhibited strong fluorescence in the cytoplasm and nucleus. Significant accumulation of nanocomposites was observed in the brain after administration of the in situ gel group, and maximum accumulation was reached at 12 h. A small amount of accumulation was observed in the nanocomposite solution group only at 2 h. Therefore, the direct nasal brain transport efficiency of PAMAM dendrimer nanocomposites can be significantly improved after combining with in situ gel. PAMAM dendrimer nanocomposite/DGG is a potential drug delivery system for nasal brain transport.

Origins, Phytochemistry, Pharmacology, Analytical Methods and Safety of Cortex Moutan (Paeonia suffruticosa Andrew): A Systematic Review

Cortex Moutan (CM), a well-known traditional Chinese medicine, is commonly used for treating various diseases in China and other eastern Asian countries. Recorded in Pharmacopeias of several countries, CM is now drawing increasing attention and under extensive studies in various fields. Phytochemical studies indicate that CM contains many valuable secondary metabolites, such as monoterpene glycosides and phenols. Ample evidence from pharmacological researches suggest that CM has a wide spectrum of activities, such as anti-inflammatory, anti-oxidant, anti-tumor, anti-diabetic, cardiovascular protective, neuroprotective, hepatoprotective effects. Moreover, various analytical methods were established for the quality evaluation and safety control of CM. This review synopsizes updated information concerning the origins, phytochemistry, pharmacology, analytical method and safety of CM, aiming to provide favorable references for modern CM research and application. In conclusion, continuing pharmacological investigations concerning CM should be conducted to unravel its pharmacological mechanisms. Further researches are necessary to obtain comprehensive and applicable analytical approach for quality evaluation and establish harmonized criteria of CM.

Integrated identification, qualification and quantification strategy for pharmacokinetic profile study of Guizhi Fuling capsule in healthy volunteers

Guizhi Fuling capsule (GZFL), a traditional Chinese medicine formulation, is widely used in China to relieve pain from dysmenorrhea and is now in a Phase II clinical trial in the USA. Due to the low exposure of the five main medicative ingredients (amygdalin, cinnamic acid, gallic acid, paeoniflorin and paeonol) of GZFL in human, a strategy was built to qualitatively and quantitatively identify the possible metabolites of GZFL and to describe the pharmacokinetic profiles of GZFL in human. In this strategy, LC-Q-TOF/MS was used to identify and structurally elucidate the possible metabolites of GZFL in vivo; and a time-based metabolite-confirming step (TBMCs) was used to confirm uncertain metabolites. The simultaneously quantitation results by LC-MS/MS showed low exposure of the five medicative ingredients. According to the strategy we built, a total of 36 metabolites were found and structurally elucidated. The simultaneously semi-quantitative analysis by LC-MS/MS showed that obvious time-concentration curves could be established for 12 of the metabolites, and most of them showed a relatively higher exposure. This study provides a better understanding of the metabolic processes of GZFL in human.

Metabolic profiling of antioxidants constituents in Artemisia selengensis leaves

This study aimed to evaluate the antioxidant potential of Artemisia selengensis Turcz (AST) leaves, a byproduct when processing AST stalk, and identify the antioxidant constituents by using HPLC-QTOF-MS(2). The total phenolics content (TPC), total flavonoids content (TFC) and antioxidant abilities of fractions resulted from the successively partition of chloroform, ethyl acetate and n-butanol were compared. Ethyl acetate fraction (EAF) exhibited the highest TFC (65.44 mg QuE/g fraction), n-butanol fraction (nBuF) showed the highest TPC (384.78 mg GAE/g fraction) and the best DPPH scavenging ability, ABTS(+) scavenging ability and reducing power. Totally, 57 compounds were identified or tentatively identified in nBuF and EAF, 40 of them were reported in AST for the first time. The major constituents in EAF were flavonoids, and the major constituents in nBuF were phenolic acids and organic acids. Thus, AST leaves might be a potential low-cost resource of natural antioxidants.

Analysis of phenolic acids of Jerusalem artichoke (Helianthus tuberosus L.) responding to salt-stress by liquid chromatography/tandem mass spectrometry

Plant phenolics can have applications in pharmaceutical and other industries. To identify and quantify the phenolic compounds in Helianthus tuberosus leaves, qualitative analysis was performed by a reversed phase high-performance liquid chromatography coupled with tandem mass spectrometry (HPLC-MS/MS) and quantitative analysis by HPLC. Ten chlorogenic acids (CGAs) were identified (3-o-caffeoylquinic acid, two isomers of caffeoylquinic acid, caffeic acid, p-coumaroyl-quinic acid, feruloylquinic acid, 3,4-dicaffeoyquinic acid, 3,5-dicaffeoylquinic acid, 1,5-dicaffeoylquinic acid, and 4,5-dicaffeoylquinic acid) by comparing their retention times, UV-Vis absorption spectra, and MS/MS spectra with standards. In addition, four other phenolic compounds, including caffeoyl glucopyranose, isorhamnetin glucoside, kaempferol glucuronide, and kaempferol-3-o-glucoside, were tentatively identified in Helianthus tuberosus leaves for the first time. The 3-o-caffeoylquinic acid (7.752 mg/g DW), 4,5-dicaffeoylquinic acid (5.633 mg/g DW), and 3,5-dicaffeoylquinic acid (4.900 mg/g DW) were the major phenolic compounds in leaves of Helianthus tuberosus cultivar NanYu in maturity. The variations in phenolic concentrations and proportions in Helianthus tuberosus leaves were influenced by genotype and plant growth stage. Cultivar NanYu had the highest concentration of phenolic compounds, in particular 3-o-caffeoylquinic acid and 4,5-dicaffeoylquinic acid compared with the other genotypes (wild accession and QingYu). Considering various growth stages, the concentration of total phenolics in cultivar NanYu was higher at flowering stage (5.270 mg/g DW) than at budding and tuber swelling stages. Cultivar NanYu of Helianthus tuberosus is a potential source of natural phenolics that may play an important role in the development of pharmaceuticals.

Investigation of the absorbed and metabolized components of Danshen from Fuzheng Huayu recipe and study on the anti-hepatic fibrosis effects of these components

ETHNOPHARMACOLOGY

Fuzheng Huayu recipe (FZHY) was formulated on the basis of Chinese medicine theory in treating liver fibrosis. It has a significant efficacy against liver fibrosis caused by chronic hepatitis B, with the action mechanisms of inhibition of hepatic stellate cell activation, protection of hepatocyte oxidative injury and regulations of hepatic matrix remodeling etc.

AIM OF THE STUDY

To identify the absorbed components and metabolites of Danshen in FZHY in rat serum, and find their active components for anti-liver fibrosis.

MATERIAL AND METHODS

A valid high performance liquid chromatography-electrospray ionization ion trap mass spectrometry (HPLC-ESI/MS(n)) method was established to investigate the absorbed and metabolized compounds of Danshen in FZHY in rat serum after oral administration. Mass spectra were acquired in both negative and positive modes. Otherwise, to evaluate the anti-hepatic fibrosis efficacies of absorbed and metabolized compounds, the LX-2 cell line of hepatic stellate cell (HSC), which was crucial cellular basis of fibrogenesis, was cultured and incubated with absorbed compounds, the cytotoxicity was determined with the cellomics Multiparameter Cytotoxicity Kit 1 by High Content Screening (HCS), the cell proliferation was assayed with EdU-DNA incorporation, and the cell activation was analyzed through α-smooth muscle actin (α-SMA) expression with high content screening technology.

RESULTS

More than 11 compounds and 2 metabolites from Danshen were identified in the serum after oral administration of FZHY by comparing their mass spectra and retention behavior with reference compounds or literature data. Among these compounds, there were no obvious changes in nuclear morphology, membrane permeability with blow 96 μM of six polar compounds treatment in comparison with control cells, respectively. And the salvianolic acid B (6 μM, 48 μM), caffeic acid (6 μM, 48 μM) and rosmarinic acid (48 μM) could obviously inhibit LX-2 cells proliferation, down-regulate α-SMA expression.

CONCLUSION

The results proved that the established method could be applied to analyze the absorbed into blood compounds of Danshen after oral administration FZHY. These absorbed compounds included 11 compounds and 2 metabolites of Danshen. Among them, the salvianolic acid B, caffeic acid and rosmarinic acid were the effective components of FZHY to anti-hepatic fibrosis effects.

Bioactivities and serum pharmacochemistry of Qi-Wei-Xiao-Yan-Tang

CONTEXT

Qi-Wei-Xiao-Yan-Tang (XYT), composed of Radix et Rhizoma Rhei, Radix Astragali, Radix Wikstroemiae Indicae, Fructus Ligustri Lucidi, Poria and Radix Glycyrrhizae, has been widely used as an anti-inflammatory drug.

OBJECTIVE

The present study investigated the anti-inflammatory, antibacterial effects and serum pharmacochemistry of XYT.

METHODS

The dimethylbenzene-induced inflammation test, the acetic acid-induced vascular permeability test and the carrageenan-induced paw edema test were used to evaluate the anti-inflammatory activity of XYT (200, 100 and 50 mg/kg); minimal inhibitory concentration (MIC). Minimal bactericidal concentration (MBC) tests were used to evaluate the antibacterial activity of XYT. Additionally, serum pharmacochemistry was performed to study the biologically active substances.

RESULTS

All the tests for anti-inflammatory effects were shown active with these test systems; the anti-inflammatory effects at doses of 100 and 200 mg/kg were significant (p < 0.05); MIC and MBC tests indicated that XYT showed a broader antimicrobial spectrum and stronger toxicity to the tested microbes. Additionally, calycosin-7-glucoside, sennoside A, aloeemodin and rhein were detected as the predominant components in rat serum which may play the key role in the anti-inflammatory activities of XYT.

CONCLUSIONS

This is the first report of the pharmacological activities and serum pharmacochemistry of XYT, and the first evidence of anti-inflammatory and antimicrobial properties of the extracts of XYT. The results of our work demonstrated that XYT has significant anti-inflammatory and antibacterial properties, and calycosin-7-glucoside, sennoside A aloeemodin and rhein may be the biologically active substances of XYT. XYT can be utilized as an effective and safe disease preventive or therapeutic agent.

Screening and analysis of the multiple absorbed bioactive components and metabolites of Baihe Zhimu Tang by the metabolic fingerprinting technique and liquid chromatography/diode array detection-electrospray ionization-mass spectrometry

BACKGROUND

Baihe Zhimu Tang (BZT) is a widely used traditional Chinese medicinal formula in treating various diseases; however, its active components have remained unknown.

MATERIALS AND METHODS

Based on the metabolic fingerprinting technique and liquid chromatography/diode array detection-electrospray ionization-mass spectrometry (LC/DAD-ESI-MS), a method for rapid screening and analysis of the multiple absorbed bioactive components and metabolites of an oral solution of Baihe Zhimu Tang (BZT) in rabbit plasma, urine and feces after oral administration of BZT was developed.

RESULTS

The results obtained from a comprehensive comparative analysis of the fingerprints of the BZT and its metabolic fingerprints in rabbit biological samples indicated that 19 components in the BZT were absorbed into the rabbit's body. Both of them were tentatively identified from their MS and UV spectra and retention behaviors by comparing the results with the reported literature. In addition, only six components were found in the metabolic fingerprints, which suggested that they might be metabolites of some components in the BZT.

CONCLUSION

The findings demonstrated that the proposed method could be used to rapidly and simultaneously analyze and screen the multiple absorbed bioactive constituents and metabolites in a formula of traditional Chinese medicines (TCMs) by comparing and contrasting the chromatographic fingerprints with its metabolic fingerprints. This is very important not only for the pharmaceutical discovery process and the quality control of crude drugs, but also for explaining the curative mechanism of TCMs.

Isolation and identification of the metabolites of paeonol in human urine

Paeonol, a major component of Paeonia suffruticosa Andrews, is used in clinical situations in China as a natural anti-inflammatory agent. The aim of the present study is to investigate the metabolism of paeonol in humans. Six metabolites were isolated from human urine after oral administration of paeonol, and their structures were elucidated as resacetophenone (M1), resacetophenone-2-O-sulfate (M2), 2-hydroxy-4-methoxyacetophenone-5-O-sulfate(M3), 2-hydroxy-4-methoxyacetophenone-5-O-glucopyranuronoside (M4), 2-hydroxyacetophenone-4-O-glucopyranuronoside (M5) and 2,5-dihydroxy-4-methoxyacetophenone(M6) by a series of analyses involving mass spectrometry, (1)H NMR, (13)C NMR and NOESY spectra. In addition, three more metabolites 2,4-dihydroxyacetophenone-5-O-sulfate (M7), paeonol-2-O-glucopyranuronoside (M8) and paeonol-2-O-sulfate (M9), were identified in human urine by using a UPLC/Q-TOF-MS/MS method. This is the first study of paeonol metabolism in humans. Based on the identified metabolites, possible metabolic pathways of paeonol in humans are proposed. Paeonol is metabolized mainly by hydroxylation and demethylation to give the corresponding phase I metabolites, M1, M6 and 2,4,5-trihydroxyacetophenone, and which then underwent conjugation with glucuronic acid or sulfuric acid to form phase II metabolites.

Screening and analysis of the multiple absorbed bioactive components and metabolites in rat plasma after oral administration of Jitai tablets by high-performance liquid chromatography/diode-array detection coupled with electrospray ionization tandem mass spectrometry

Based on the serum pharmacochemistry technique and high-performance liquid chromatography/diode-array detection (HPLC/DAD) coupled with electrospray tandem mass spectrometry (HPLC/ESI-MS/MS), a method for screening and analysis of the multiple absorbed bioactive components and metabolites of Jitai tablets (JTT) in orally dosed rat plasma was developed. Plasma was treated by methanol precipitation prior to liquid chromatography, and the separation was carried out on a Symmetry C(18) column, with a linear gradient (0.1% formic acid/water/acetonitrile). Mass spectra were acquired in negative and positive ion modes, respectively. As a result, 26 bioactive components originated from JTT and 5 metabolites were tentatively identified in orally dosed rat plasma by comparing their retention times and MS spectra with those of authentic standards and literature data. It is concluded that an effective and reliable analytical method was set up for screening the bioactive components of Chinese herbal medicine, which provided a meaningful basis for further pharmacology and active mechanism research of JTT.

Identification and quantitative determination of a major circulating metabolite of gambogic acid in human

Gambogic acid (GA), a promising anticancer candidate, is a polyprenylated xanthone abundant in the resin of Garcinia morella and Garcinia hanburyi. The major circulating metabolite of GA in human, 10-hydroxygambogic acid (10-OHGA), was identified by comparison of the retention time and mass spectra with those of reference standard using liquid chromatography-tandem mass spectrometry. The reference standard of 10-OHGA was isolated from bile samples of rats after intravenous injection of GA injection, and its structure was confirmed by NMR. Then, a selective and sensitive method was developed for the quantitative determination of this metabolite in human plasma. After liquid-liquid extraction by ethyl acetate, the analyte and the internal standard were separated on a Sepax HPC18 column (100 mm x 2.1 mm i.d., 3.0 microm) with a mobile phase of 10mM ammonium acetate water solution containing 0.1% formic acid-acetonitrile (20:80, v/v). The detection was performed on a single quadrupole mass spectrometer equipped with electrospray ionization (ESI) source. The calibration curve was linear over the range of 3-2000 ng/mL for 10-OHGA. The developed quantification method can now be used for the pharmacokinetic and pharmacological studies of 10-OHGA after intravenous infusion of GA injection in human.

Screening of antinociceptive components in Corydalis yanhusuo W.T. Wang by comprehensive two-dimensional liquid chromatography/tandem mass spectrometry

Formalin-induced pain models were used in rats to evaluate the antinociceptive effect of the total alkaloids of Corydalis yanhusuo (TAC). The results indicated that formalin-evoked spontaneous nociceptive responses (licking behavior) could be inhibited significantly by giving (intragingival) TAC at a single dose of 150 mg/kg. Subsequently, an online comprehensive two-dimensional biochromatography method with a silica-bonded human serum albumin (HSA) column in the first dimension and a monolithic ODS column in the second was developed. The absorbed bioactive components were screened by comparing and contrasting the components detected in the plasma and striatum with those in TAC. More than 100 compounds were separated and detected in the TAC, among which 13 compounds were identified. About 40 compounds (seven compounds identified) were absorbed into the plasma with appropriate concentrations and about 20 compounds (four compounds identified) passed through the blood-brain barrier into the striatum. Of interest, four compounds (protopine, glaucine, tetrahydropalmatine, and corydaline) which were reported to possess profound antinociceptive effects exhibited high concentrations in the striatum. This may result from their synergistic effects in regulating the formalin-induced nociception. The results indicated that the comprehensive two-dimensional biochromatography method developed is capable of screening the bioactive components in Corydalis yanhusuo and providing valuable information for understanding the mechanisms by which Corydalis yanhusuo alleviates nociception.

Comparison of electron capture-atmospheric pressure chemical ionization and electrospray ionization for the analysis of gambogic acid and its main circulating metabolite in dog plasma

Gambogic acid (GA), a promising anticancer candidate, is a polyprenylated xanthone abundant in the resin of Garcinia morella and Garcinia hanburyi. Electron capture-atmospheric pressure chemical ionization (EC- APCI) and electrospray ionization (ESI) techniques, both in the negative ion mode, were evaluated regarding ionization, fragmentation patterns and sensitivity for simultaneous liquid chromatography-tandem mass spectrometry (LC-MS/MS) analysis of GA and its main circulating metabolite, 10-hydroxygambogic acid (10-OHGA) in dog plasma. Both analytes underwent extensive in-source fragmentation in EC-APCI, which was not desirable for reliable quantification of these analytes, whereas the substitution of ESI for EC-APCI almost eliminated the source instability of both analytes. Negative ion ESI was, therefore, chosen for the development of an LC-MS/MS method for simultaneous determination of these analytes. After protein precipitation by acetonitrile, all analytes were separated on a Luna C18 HST column (50 x 2.0 mm i.d., 2.5 microm) with a mobile phase of 20 mmol L(-1) ammonium acetate water solution containing 0.2% acetic acid:acetonitrile (18:82, v/v). The detection was performed on a tandem mass spectrometer using selective reaction monitoring mode. Calibration curves were linear over the range of 10-6000 ng mL(-1) for GA and 3-2000 ng mL(-1) for 10-OHGA. The method was successfully applied to the pharmacokinetics study of GA injection in six beagle dogs.

Identification of the metabolites of ecabet bismuth in rat bile by liquid chromatography-electrospray ionization-tandem mass spectrometry

In the present study, a liquid chromatography-electrospray ionization-tandem mass spectrometry (LC-ESI- MS/MS) method was developed for the screening and the structural elucidation of the metabolites of ecabet bismuth in rat bile. Solid-phase extraction cartridges were used for sample pre-treatment and a gradient liquid chromatographic system composed of 10 mM ammonium acetate buffer and methanol was used for chromatographic separation on a Phenomenex Kromasil C(18) column. The triple quadrupole mass spectrometer was employed to thoroughly detect and acquire the detailed MS/MS spectra of ecabet and its metabolites. By comparing the chromatographic retention behaviors, as well as the changes in molecular weight and full-scan MS/MS spectra of the potential metabolites with those of the parent compound, two main metabolites were identified as glucuronide conjugate of carbonylated ecabet (7-oxo-ecabet) and glucuronide conjugate of ecabet. Both two metabolites have not been reported in the literatures. The metabolic pathways of ecabet in rat were also proposed in this paper.

Advancement in analysis of Salviae miltiorrhizae Radix et Rhizoma (Danshen)

This review summarizes the recent advances in the chemical analysis of Danshen and its finished products, including the introduction of the identified bioactive components, analytical methods for quantitative determination of target analytes and fingerprinting authentication, quality criteria of Danshen crude herb and its preparations, as well as the pharmacokinetic and pharmacodynamic studies on the active components of Danshen and its finished products. Danshen contains mainly two types of constituents, the hydrophilic depsides and lipophilic diterpenoidal quinones and both of them are responsible for the pharmacological activities of Danshen. In order to monitor simultaneously both types of components which have different physicochemical properties, numerous analytical methods have been reported using various chromatographic and spectrophotometric technologies. In this review, 110 papers on analysis of Danshen are discussed, various analytical methods and their chromatographic conditions are briefly described and their advantages/disadvantages are compared. For obtaining a quick, accurate and applicable analytical approach for quality evaluation and establishing a harmonized criteria of Danshen and its finished products, the authors' suggestion and opinions are given, including the reasonable selection of marker compounds with high concentration and commercial availability, a simple sample preparation procedure with high recoveries of both the hydrophilic phenols and lipophilic tanshinones, and an optimized chromatographic condition with ideal resolutions of all the target components. The chemical degradation and transformation of the predominant constituent salvianolic acid B in Danshen during processing and manufacturing are also emphasized in order to assure the quality consistency of Danshen containing products.

Liquid chromatography–tandem mass spectrometry analysis of protocatechuic aldehyde and its phase I and II metabolites in rat

A method using liquid chromatography-electrospray ionization tandem mass spectrometry (LC-MS/MS) analysis was established for the identification of metabolites in rat after oral administration of protocatechuic aldehyde, a major bioactive phenolic acid in the roots of Salvia miltiorrhiza. Eleven metabolites in rat plasma and urine were firstly identified as protocatechuic aldehyde, protocatechuic acid and their methylated, glucuronized or glycine conjugates on the basis of their MS fragmentation behaviors, while nine of these metabolites (except protocatechuic aldehyde and protocatechuic acid) were detected in rat bile. In addition, the possible metabolic pathway was proposed for the first time. In the phase I metabolism, protocatechuic aldehyde could be oxidized to protocatechuic acid. The conjugates would be formed in rat intestine, liver and kidney and excreted from rat urine and bile. Enthrohepatic circulation played an important role in the metabolism of protocatechuic aldehyde. The results proved that the established method was simple, reliable and sensitive, revealing that it could be used to rapid screen and identify the structures of active components responsible for pharmacological effects of protocatechuic aldehyde and to better understand its in vivo metabolism.

Identification of tanshinones and their metabolites in rat bile after oral administration of TTE-50, a standardized extract of Salvia miltiorrhiza by HPLC–ESI–DAD–MSn

TTE-50 is a standardized extract of Salvia miltiorrhiza which mainly consisted of tanshinones. A sensitive and specific method using liquid chromatography-diode array detection-electrospray ionization (ESI) ion trap mass spectrometry was established for the study of the constituents and metabolites of TTE-50 in rat bile sample after oral administration. The bile samples were extracted with ethyl acetate (EtOAc) of three-fold volume for three times. The chromatographic separation was carried out on a Zorbax Extend-C18 column with a gradient elution program whereas acetonitrile-water was used as mobile phase. Mass spectra were acquired in positive ionization mode and data-dependant scan was used for the identification of the tanshinones and metabolites in the bile samples. Identification and structural elucidation of the tanshinones and their metabolites in bile samples were performed by comparing their retention-times and full scan MS(n) spectra with those of reference compounds and data in the literatures. Sixteen tanshinones in TTE-50 along with seventeen phase I metabolites were identified simultaneously. The metabolic modification could take place in the C-4 side chain of tanshinone IIA, from methyl to primary alcohol, then to aldehyde group was proposed for the first time. The established method was valuable for the study of the metabolism of complex system such as herbal extracts or traditional Chinese medicine (TCM) formula.