Mid-infrared spectroscopic identification of the right-baked rhubarb for ulcerative colitis therapy.

Clinical and experimental evidences have confirmed the significant therapeutic effects of rhubarb on ulcerative colitis (UC), but the strong purgative function of rhubarb also aggravates UC symptoms such as bloody diarrhea. Stir-baking to scorch is a traditional Chinese medicinal processing method that can eliminate the adverse purgative function while keep or even enhance the UC therapeutic function of rhubarb. However, the under-baked rhubarb still have the undesirable purgative function, but the over-baked rhubarb may lose the required medicinal functions. Therefore, the determination of the right endpoint is the primary quality concern about the baking process of rhubarb. In this research, typical anthraquinone compounds and mid-infrared (MIR) spectra were recruited to determine the best baking degree of rhubarb for UC therapy. Raw rhubarb slices were baked at 180 °C with rotation to prepare the rhubarbs with different baking degrees. The right-baked rhubarb was defined according to the UC therapeutic responses as well as the traditional color criterion. Referring to the typical anthraquinone compounds in rhubarb slices and extracts, the baking degree of rhubarb may be assessed by the conversion ratio of anthraquinone glycosides to anthraquinone aglycones. MIR spectra showed the gradual decompositions of organic compounds including anthraquinone glycosides and tannins during the baking process. Rhubarbs with different baking degrees can be distinguished clearly by MIR-based principal component analysis. In conclusion, the ratio of anthraquinone glycosides to anthraquinone aglycones may be a reasonable chemical indicator of the right-baked rhubarb. Meanwhile, MIR spectroscopy can identify the right-baked rhubarb simply and rapidly.

Chemical Profiling of Shen-Wu-Yi-Shen Tablets Using UPLC-Q-TOF-MS/MS and Its Quality Evaluation Based on UPLC-DAD Combined with Multivariate Statistical Analysis.

Shen-Wu-Yi-Shen tablets (SWYST) is a traditional Chinese medicine prescription used for treating chronic kidney disease (CKD). This study aims to characterize the constituents in SWYST and evaluate the quality based on the quantification of multiple bioactive components. SWYST samples were analyzed with ultra-high-performance liquid chromatography quadrupole time-of-flight mass spectrometry (UPLC-Q-TOF-MS) and a data-processing strategy. As a result, 215 compounds in SWYST were unambiguously identified or tentatively characterized, including 14 potential new compounds. Meanwhile, strategies based on characteristic fragments for rapid identification were summarized, indicating that the qualitative method is accurate and feasible. Notably, the glucose esters of laccaic acid D-type anthraquinone were first found and their fragmentation patterns were described by comparing that of O-glycoside isomers. Besides, based on comparisons of the cleavage ways of mono-acyl glucose with different acyl groups or acylation sites, differences in fragmentation pathways between 1,2-di-O-acyl glucose and 1,6-di-O-acyl glucose were proposed for the first time and verified by reference substances. In addition, a validated UPLC-DAD was established for the determination of 11 major bioactive components related to treatment of CKD (albiflorin, paeoniflorin, 2,3,5,4'-tetrahydroxy-stilbene-2-O-ß-d-glucoside (TSG), 1-O-galloyl-2-O-cinnamoyl-ß-d-glucose, emodin-8-O-ß-d-glucoside, chrysophanol-O-ß-d-glucoside, aloe-emodin, rhein, emodin, chrysophanol and physcion). Moreover, TSG and 1-O-galloyl-2-O-cinnamoyl-ß-d-glucose were found as the quality markers related to the origins of SWYST based on multivariate statistical analysis. Conclusively, the findings in this work provide a feasible reference for further studies on quality research and mechanisms of action in treating CKD.

The haplotype-resolved genome assembly of autotetraploid rhubarb Rheum officinale provides insights into its genome evolution and massive accumulation of anthraquinones.

Rheum officinale, a member of the Polygonaceae family, is an important medicinal plant that is widely used in traditional Chinese medicine. Here, we report a 7.68-Gb chromosome-scale assembly of R. officinale with a contig N50 of 3.47 Mb, which was clustered into 44 chromosomes across four homologous groups. Comparative genomics analysis revealed that transposable elements have made a significant contribution to its genome evolution, gene copy number variation, and gene regulation and expression, particularly of genes involved in metabolite biosynthesis, stress resistance, and root development. We placed the recent autotetraploidization of R. officinale at ∼0.58 mya and analyzed the genomic features of its homologous chromosomes. Although no dominant monoploid genomes were observed at the overall expression level, numerous allele-differentially-expressed genes were identified, mainly with different transposable element insertions in their regulatory regions, suggesting that they functionally diverged after polyploidization. Combining genomics, transcriptomics, and metabolomics, we explored the contributions of gene family amplification and tetraploidization to the abundant anthraquinone production of R. officinale, as well as gene expression patterns and differences in anthraquinone content among tissues. Our report offers unprecedented genomic resources for fundamental research on the autopolyploid herb R. officinale and guidance for polyploid breeding of herbs.

Characterization of the physiological parameters, effective components, and transcriptional profiles of Polygonum multiflorum Thunb. Under pH stress.

Polygonum multiflorum Thunb. is a traditional Chinese medicine with extensive distribution and robust adaptability, but comprehensive research on its acid and alkali resistance is presently lacking. This study aimed to analyze the effects of 5 months of continuous pH stress on the physiological and photosynthetic parameters of P. multiflorum, and the content of effective components. Results revealed that pH stress significantly influenced the normal growth, physiological functions, and photosynthetic indicators of P. multiflorum. At soil pH 4.5, the tubers of P. multiflorum exhibited the highest levels of 2,3,5,4'-tetrahydroxy stilbene-2-O-ß-d-glucoside (THSG) and total anthraquinones at 5.41% and 0.38%, respectively. However, increased soil pH significantly reduced the content of THSG and total anthraquinones. Reference-free transcriptome analysis was further conducted on P. multiflorum treated at pH 4.5 and 9.5, generating a total of 47,305 unigenes with an N50 of 2118 bp, of which 31,058 (65.65%) were annotated. Additionally, 2472 differentially expressed genes (DEGs) were identified. Among them, 17 DEGs associated with the biosynthesis of THSG and anthraquinones were screened. A comprehensive analysis of differential gene expression and effective component content demonstrated a significant positive correlation between the content of effective components and the 14 DEGs' expression but a negative correlation with soil pH. This study highlighted the influence of varying soil pH values on the effective component content of P. multiflorum. Specific acidic conditions proved beneficial for the synthesis and accumulation of THSG and total anthraquinones in P. multiflorum, thereby enhancing the quality of the medicinal material.

Contamination of tea leaves by anthraquinone: The atmosphere as a possible source.

The detection of anthraquinone in tea leaves has raised concerns due to a potential health risk associated with this species. This led the European Union to impose a maximum residue limit (MRL) of 0.02 mg/kg for anthraquinone in dried tea leaves. As atmospheric contamination has been identified as one of the possible sources of anthraquinone residue, this study investigates the contamination resulting from the deposition of atmospheric anthraquinone using a global chemical transport model that accounts for the emission, atmospheric transport, chemical transformation, and deposition of anthraquinone on the surface. The largest contribution to the global atmospheric budget of anthraquinone is from residential combustion followed by the secondary formation from oxidation of anthracene. Simulations suggest that atmospheric anthraquinone deposition could be a substantial source of the anthraquinone found on tea leaves in several tea-producing regions, especially near highly industrialized and populated areas of southern and eastern Asia. The high level of anthraquinone deposition in these areas may result in residues in tea products exceeding the EU MRL. Additional contamination could also result from local tea production operations.

[Material basis of Rhei Radix et Rhizoma-Coptidis Rhizoma combination in alleviating "bitter-cold" properties based on supramolecular chemistry of Chinese medicine].

The present study aimed to explore the material basis of Rhei Radix et Rhizoma-Coptidis Rhizoma combination in alleviating "bitter-cold" properties based on the supramolecular chemistry of Chinese medicine.Dynamic light scattering and scanning/transmission electron microscopy were used to characterize the morphological characteristics of supramolecules in the decoction of Rhei Radix et Rhizoma and Coptidis Rhizoma.The chemical composition of supramolecules, as well as the dissolution and release processes of supramolecules and the medicinal components of Coptidis Rhizoma decoction, was determined by the high-performance liquid chromatography-mass spectrometry.The differences in "bitter-cold" medicinal properties between Rhei Radix et Rhizoma decoction, Coptidis Rhizoma decoction, and co-decoction were analyzed by sensory evaluation, electronic tongue, mouse diarrhea model, and pathological indicators.The anthraquinones/tannins and alkaloids interacted to form supramolecules with a scale of about 400 nm when Rhei Radix et Rhizoma and Coptidis Rhizoma were decocted together, which delayed the dissolution and release of the active components represented by berberine. Compared with the consequence of single drug administration at 4 g·kg~(-1), the combination of the two drugs at 8 g·kg~(-1) significantly alleviated the "bitter-cold" properties.The effective components interacted to form supramolecules in the co-decoction of Rhei Radix et Rhizoma and Coptidis Rhizoma, which affected the dissolution and release of the effective components of Chinese medicinal decoction, thereby alleviating the "bitter-cold" properties.The findings of this study provide a new idea for revealing the scientific compatibility of Rhei Radix et Rhizoma and Coptidis Rhizoma.

Determination of Total Sennosides and Sennosides A, B, and A1 in Senna Leaflets, Pods, and Tablets by Two-Dimensional qNMR.

In the present work, a two-dimensional qNMR method for the determination of sennosides was established. Using band-selective HSQC and the cross correlations of the characteristic 10-10' bonds, we quantified the total amount of the value-determining dianthranoids in five minutes, thus, rendering the method not only fast, but also specific and stability indicating. The validation of the method revealed excellent accuracy (recovery rates of 98.5 to 103%), precision (RSD values of 3.1%), and repeatability (2.2%) and demonstrated the potential of 2D qNMR in the quality control of medicinal plants. In a second method, the use of 2D qNMR for the single analysis of sennosides A, B, and A1 was evaluated with acceptable measurement times (31 min), accuracy (93.8%), and repeatability (5.4% and 5.6%) for the two major purgatives sennoside A and B. However, the precision for sennoside B and A1 was not satisfactory, mainly due to the low resolution of the HSQC signals of the two compounds.

Phytochemical Analysis of Acaciaehrenbergiana (Hayne) Grown in Qatar: Identification of Active Ingredients and Their Biological Activities.

Acacia ehrenbergiana (Hayne), also known as Salam, is a highly drought resistant shrub distributed in North and East Africa, and the Arabian Peninsula. The plant is gathered for its gum and fiber, and is an important legume species for indigenous populations. In this study, the phytochemical analysis, antibacterial, and antioxidant properties of various alcoholic and aqueous extracts of Acacia ehrenbergiana grown in Qatar were investigated. The qualitative phytochemical screening of this species exhibited the presence of glycosides, tannins, flavonoids, terpenoids, saponins, phenol, and anthraquinones in various extracts. The agar diffusion method was performed to check the antibacterial activity. The acetone and ethanol extracts showed 85% antibacterial activity of the control against Gram-negative E. coli, while the acetone extract had 65% activity against the Bacillus Gram-positive species. The highest activity against Staphylococcus aureus was 65% for the butanol extract. The antioxidant capacities were evaluated by the DPPH method. Various extracts exhibited antioxidant activities similar to or higher than standard antioxidants, with the highest percent inhibition of 95% for the acetone and ethanol extracts. The acetone extracts were further purified by reverse phase combiflash chromatography followed by HPLC. Three of the pure compounds isolated were subjected to MS, FTIR, and NMR spectral analysis and were found to be stigmasterol, spinasterol, and theogallin. In conclusion, the observed antibacterial and antioxidant activities as well as the presence of secondary metabolites with potential medicinal activities makes Acacia ehrenbergiana a potent valuable endemic medicinal plant.

Exploratory Quality Control Study for Polygonum multiflorum Thunb. Using Dinuclear Anthraquinones with Potential Hepatotoxicity.

In recent years, the hepatotoxicity of Polygoni Multiflora Radix (PMR) has attracted increased research interest. Some studies suggest that anthraquinone may be the main hepatotoxic component. Most of the relevant studies have focused on the mononuclear anthraquinone component rather than binuclear anthraquinones. The hepatotoxicity of dinuclear anthraquinone (dianthrone) was investigated in a cell-based model. Next, a method for the determination of six free and total dianthonones in PMR and PMR Praeparata (PMRP) was established using ultra-high-performance liquid chromatography triple quadrupole mass spectrometry (UPLC-QQQ-MS/MS), which was then used to analyze the collected samples. The data show that four binuclear anthraquinone compounds were hepatotoxic and may be potential toxicity indicators for the safety evaluation of PMR and PMRP. Herein, we provide a theoretical basis for the improvement of PMRP quality standards.

Optimisation of microwave-assisted extraction (MAE) of anthraquinone and flavonoids from Senna alata (L.) Roxb.

This paper investigates the optimum processing conditions of microwave assisted extraction (MAE) of anthraquinone (aloe emodin, AE) and flavonoids (kaempferol 3-gentiobioside, K3G and kaempferol, KA) from Senna alata (L.) Roxb. The kinetic study indicates that MAE showed a greater extraction rate, compared to ultrasonic-assisted and maceration, due to the enhanced power which altered the leaf microstructures. The optimisation was undertaken using one-factor-at-a-time, two-level factorial design and central composite design were used to maximise the yield of the target compounds. The optimum yield of K3G (4.27 mg/g DW), KA (8.54 mg/g DW) and AE (0.86 mg/g DW) was obtained at 90.5% ethanol, microwave power of 18.6 W/mL with a desirability of 0.82. In addition, the yield of K3G and KA is correlated positively with the antioxidant activity.

Quality evaluation of rhubarb based on qualitative analysis of the HPLC fingerprint and UFLC-Q-TOF-MS/MS combined with quantitative analysis of eight anthraquinone glycosides by QAMS.

Rhubarb is one of the most ancient and important herbal medicines, but its current quality evaluation (QE) methods have some limitations. In this study, a new method was developed for the comprehensive QE of rhubarb. First, fingerprints of 28 batches of three species of rhubarb samples were determined by HPLC, the reference fingerprint was established and the common peaks were assigned. Second, the components of common peaks in the fingerprints were identified by ultrafast liquid chromatography quadrupole time-of-flight mass spectrometry. Finally, a method for the simultaneous determination of the contents of eight anthraquinone glycosides in rhubarb using quantitative analysis of multiple components by a single marker (QAMS) was established, and the contents of these eight components in 28 batches of rhubarb determined by QAMS and the external standard method were compared. The results showed that there were 31 common peaks in the rhubarb fingerprint. The components of these 31 common peaks were identified, and 20 of them were unambiguously confirmed by reference substances, including eight anthraquinone glycosides. The contents of eight anthraquinone glycosides in the 28 batches of rhubarb determined by QAMS and the external standard method were not significantly different. In conclusion, the method established in this study can be used for the comprehensive QE of rhubarb and can also provide a reference for the QE of other herbal medicines.

Optimal fermentation time for Nigrospora-fermented tea rich in bostrycin.

BACKGROUND: Bostrycin has many biological functions, such as anticancer activity, and is becoming increasingly popular. Nigrospora sphaerica HCH285, which has the ability to produce high levels of bostrycin, can be used to ferment sun-dried green tea of Camellia sinensis through acclimation, resulting in the development of a Nigrospora-fermented tea. The effects of fermentation time on the production of bostrycin by the HCH285 strain were investigated. RESULTS: After 45 days of fermentation, the bostrycin content reached 3.18 g kg-1 , which is the highest level during the whole fermentation. At 50 days, the tea liquor was red, had a strong mushroom odour and a sweet taste, and presented optimal quality. The contents of free amino acids, tea polyphenols and soluble sugars in the fermented tea decreased generally during the fermentation, although the content of water-soluble substances increased. Additionally, the results of a 14-day acute oral toxicity test showed that Nigrospora-fermented tea was nontoxic. CONCLUSION: The optimum fermentation time of Nigrospora-fermented tea was concluded to be 45-50 days. These results provide insights with respect to the development of tea biotechnology and new tea products with active ingredients. © 2020 Society of Chemical Industry.

Self-assembled supramolecular dispersive liquid-phase microextraction for concentration and determination of anthraquinone compounds in Rhubarb.

Self-assembled supramolecular dispersive liquid-phase microextraction combined with high-performance liquid chromatography was developed and introduced for simultaneous extraction and determination of the trace level rhein, chrysophanol, and physcion in Rhubarb. Compared with conventional dispersive liquid-phase microextraction, the proposed method used a self-assembled ternary supramolecular consisting of the mixed extraction solvent (heptanol and nonanol) and dispersant (acetone) to achieve high enrichment factors of target analytes. Several factors affecting performance were investigated and optimized, including the mixed extraction solvent, type and volume of the dispersant, the pH of sample phase, salt concentration, shaking time, volume of sample phase, centrifugation time, and rate. Meanwhile, the method mechanism of self-assembled supramolecular dispersive liquid-phase microextraction was analyzed and described. Under the optimized extraction conditions, the enrichment factors of rhein, chrysophanol, and physcion were 116.5, 325.9, and 356.1, respectively. Good linearities (r ≥ 0.9952) for all analytes, low limits of detection (less than 0.04 ng/mL), satisfactory precisions (0.1-8.9%), and accuracies (recoveries, 88.2-104.1%) were achieved. The experimental results showed that the approach was simple, fast, with short extraction time, high enrichment factors, good linearities, and low limits of detection.

MALDI-HRMS Imaging Maps the Localization of Skyrin, the Precursor of Hypericin, and Pathway Intermediates in Leaves of Hypericum Species.

Hypericum perforatum and related species (Hypericaceae) are a reservoir of pharmacologically important secondary metabolites, including the well-known naphthodianthrone hypericin. However, the exact biosynthetic steps in the hypericin biosynthetic pathway, vis-à-vis the essential precursors and their localization in plants, remain unestablished. Recently, we proposed a novel biosynthetic pathway of hypericin, not through emodin and emodin anthrone, but skyrin. However, the localization of skyrin and its precursors in Hypericum plants, as well as the correlation between their spatial distribution with the hypericin pathway intermediates and the produced naphthodianthrones, are not known. Herein, we report the spatial distribution of skyrin and its precursors in leaves of five in vitro cultivated Hypericum plant species concomitant to hypericin, its analogs, as well as its previously proposed precursors emodin and emodin anthrone, using MALDI-HRMS imaging. Firstly, we employed HPLC-HRMS to confirm the presence of skyrin in all analyzed species, namely H. humifusum, H. bupleuroides, H. annulatum, H. tetrapterum, and H. rumeliacum. Thereafter, MALDI-HRMS imaging of the skyrin-containing leaves revealed a species-specific distribution and localization pattern of skyrin. Skyrin is localized in the dark glands in H. humifusum and H. tetrapterum leaves together with hypericin but remains scattered throughout the leaves in H. annulatum, H. bupleuroides, and H. rumeliacum. The distribution and localization of related compounds were also mapped and are discussed concomitant to the incidence of skyrin. Taken together, our study establishes and correlates for the first time, the high spatial distribution of skyrin and its precursors, as well as of hypericin, its analogs, and previously proposed precursors emodin and emodin anthrone in the leaves of Hypericum plants.

Liquid chromatography-mass spectrometry-based metabolomics analysis of flavonoids and anthraquinones in Fagopyrum tataricum L. Gaertn. (tartary buckwheat) seeds to trace morphological variations.

Polyphenols (flavonoids and anthraquinones) are one of the most important phytochemicals in Fagopyrum tataricum L. Gaertn. (tartary buckwheat). However, the relationship between the polyphenols of tartary buckwheat seeds and their morphological variations is unclear. We developed a liquid chromatography-mass spectrometry-based targeted metabolomics method to study the chemical profiles of 60 flavonoids and 11 anthraquinones in 40 seed cultivars (groats and hulls). Both flavonoids and anthraquinones were related to variations in seed color; the fold change from yellowish-brown to black seeds was 1.24-1.55 in groats and 0.26-0.76 in hulls. Only flavonoids contributed to significant differences in seed shape; the fold change from long to short seeds was 1.29-1.78 in groats and 1.39-1.44 in hulls. Some differential metabolites were identified at higher concentrations in hulls than in groats. This study provides new insights into differences in polyphenols among tartary buckwheat seeds with different color and shape.

Network Pharmacology and Bioactive Equivalence Assessment Integrated Strategy Driven Q-markers Discovery for Da-Cheng-Qi Decoction to Attenuate Intestinal Obstruction.

BACKGROUND: Intestinal obstruction (IO) is a kind of acute abdomen with high morbidity and mortality. Patients suffer from poor quality of life and tremendous financial pressure. Da-Cheng-Qi decoction (DCQD), a classical purgation prescription, has clinically been proven to be an effective treatment for IO. PURPOSE: Network pharmacology integrated with bioactive equivalence assessment was used to discover the quality marker (Q-marker) of DCQD against IO. METHODS: As there is hardly any targets recorded in database, thus the collection of IO targets was conducted by searching those of alternative diseases which have similar pathological symptoms with IO. In order to improve the reliability of the obtained targets, IO metabolomics data was introduced. Active compounds combination (ACC) was focused as potential Q-markers via component-target network analysis and function query from the identified components corresponding to the common targets. Bioequivalence between ACC and DCQD was assessed from the aspects of intestine motility (somatostatin secretion), inflammation (IL-6 secretion) and injury (wound healing assay) in vitro and was further validated in ileus rat model. PPI network analysis of core targets followed by gene pedigree classification and experimental validation confirmed the potential intervention pathway. RESULTS: A combination of 11 ingredients, including emodin, physcion, aloe-emodin, rhein, chrysophanol, gallic acid, magnolol, honokiol, naringenin, tangeretin, and nobiletin was finally confirmed bioequivalence with DQCD to some extent and could serve as Q-markers for DCQD to attenuate IO. PI3K/AKT was verified as a possible affected pathway that DCQD exerted the effectiveness against IO. CONCLUSION: For the disease with few recorded targets, searching those of alternative diseases which have similar pathological symptoms could be a feasible and effective approach. The proposed network pharmacology integrated bioactive equivalence evaluation paradigm is efficient to discover Q-marker of herbal formulae.

[Simultaneous determination of four anthraquinones in Polygonum multiflorum by QAMS].

A simple, specific and selective quantitative analysis of multi-components by single marker(QAMS) method for simultaneous determination of anthraquinones and anthraquinone glycosides in Polygonum multiflorum was developed. Four main anthraquinones and its glycosides, emodin, emodin-8-O-ß-D-glucoside, physcion and physcion-8-O-ß-D-glucoside were selected as analytes to evaluate the quality of P. multiflorum. Emodin was used as the internal standard, and the relative correction factors(RCFs) between emodin and the other three anthraquinones were calculated. Comparison of the contents of the four components in 30 batches of P. multiflorum from different regions and 12 batches decoction pieces from different manufacturers by QAMS and external standard method(ESM) showed that there was no significant difference between QAMS and ESM for quantification of the four main components by using relative error results, and the QAMS method was accurate and reliable, and had a good repeatability. In addition, compared with the results calculated by the difference method between total anthraquinone and free anthraquinone in the content determination of P. multiflorum in Chinese Pharmacopoeia, the results of direct determination combined anthraquinone by QAMS were very close to that by measured the external standard method. Therefore, simultaneous quantification of four main anthraquinones by using QAMS is suitable to evaluate the quality of P. multiflorum. Then the optimized assay method of the combined anthraquinone contents showed simple and feasible, which could be replaced and improved the quantification method of the combined anthraquinone in the current Chinese Pharmacopeia.

Analysis of the chemical components of Qixianqingming granules and their metabolites in rats by UPLC-ESI-Q-TOF-MS.

Qixianqingming granules (QXQM) comprise a traditional Chinese medicine (TCM) formula that was developed based on the combination of TCM theory and clinical practice. This formula has been proven to effectively treat asthma. In this study, an analytical procedure using ultraperformance liquid chromatography, coupled with electrospray ionization quadrupole time-of-flight mass spectrometry, was established for the rapid separation and sensitive identification of the chemical components in QXQM and its metabolites in serum of rats. Seventy-two compounds were systematically identified in QXQM, including flavonoids, terpenoids, anthraquinones, phenylethanoid glycosides, stilbenes, alkaloids, and organic acids. Thirteen prototype compounds and 29 metabolites were detected in the serum of rats. The results provided fundamental information for further studying the mechanisms and clinical application of QXQM.

Development and Validation of a UHPLC-PDA-MS Method for the Quantitative Analysis of Anthraquinones in Bulbine natalensis Extracts and Dietary Supplements.

A UHPLC-photodiode array-MS method was developed and validated for the quantification of one chromone and six anthraquinone type of compounds from Bulbine natalensis plant samples and dietary supplements. Metabolites 1:  -  7: were identified based on their retention times and electrospray ionization-MS spectra compared with a mix of previously isolated compounds. The quantification of 1:  -  7: was based on photodiode array detection. The optimized separation was achieved using a CORTECS C18 column with a gradient of water/acetonitrile as the mobile phase. Seven compounds were separated within 15 minutes with detection limits of 50 pg on the column. The analytical method was validated for linearity, repeatability, accuracy, limits of detection, and limits of quantification. The relative standard deviations for intra- and inter-day experiments were less than 5% and the recovery efficiency was 98 - 101%. Nine dietary supplements labeled as containing B. natalensis were examined. Anthraquinone-type compounds were detected in only five out of nine dietary supplements, with the total amount ranging from 11.3 to 90.4 mg per daily dose. The analytical method is simple, economic, rapid, and can be applied for quality assessment of B. natalensis and dietary supplements. Electrospray ionization-MS was used for the identification of these compounds in plant samples and dietary products.

Rapid identification of absorbed components and metabolites of Gandou decoction in rat plasma and liver by UPLC-Q-TOF-MSE.

Gandou Decoction (GDD), a well-known traditional Chinese medicine prescription, has been widely used for decades in clinical practice to treat Wilson's disease (WD) in China. However, due to lack of in vivo metabolism research, the absorbed components and metabolites of GDD have not been fully elucidated. In this study, a rapid and high-throughput ultra-performance liquid chromatography coupled with quadrupole time-of-flight tandem mass spectrometry (UPLC-Q-TOF-MSE) was applied to rapidly identify prototypes and metabolites after oral administration of GDD. On this basis, the possible metabolic pathways of the main prototypes were proposed between normal and copper-laden rats. As a result, a total of 89 GDD-related xenobiotics were detected in normal dosed rats, including 83 (36 prototypes and 47 metabolites) in plasma and 52 (21 prototypes and 31 metabolites) in liver; a total of 77 GDD-related xenobiotics were detected in copper-laden dosed rats, including 68 (31 prototypes and 37 metabolites) in plasma and 42 (19 prototypes and 23 metabolites) in liver. Our findings showed that anthraquinones, alkaloids and protostane triterpenoids as well as a few saponins, flavonoids, tannins and curcuminoids were the main absorbed chemical components of GDD in rat plasma; anthraquinones, protostane triterpenoids and curcuminoids were the major components in rat liver. Glucuronidation and sulfation were deduced to be the predominant metabolic pathways of GDD. Methylation, acetylation, reduction, hydroxylation, demethylation and deglycosylation were often occurred in the metabolic process. Furthermore, the holistic metabolic profile of GDD revealed that copper-laden rats and normal rats had certain differences in drug absorption and metabolism. This study offered a solid basis for ascertaining bioactive components and action mechanism of GDD.