Quality differentiation method of similar phytomedicines with high sugar content based on the sugar-marker: Taking Schisandrae Chinensis Fructus and Schisandrae Sphenantherae Fructus as an example

Quality evaluation of phytomedicines is limited to small molecules as quality markers, even for herbs with high sugar contents. We established a high-resolution method for distinguishing similar medicinal materials using sugar as quality marker, taking Schisandrae Chinensis Fructus (SCF) and Schisandrae Sphenantherae Fructus (SSF) as an example. High performance liquid chromatography with an evaporative light-scattering detector (HPLC-ELSD), high performance size exclusion chromatography coupled with multi-angle laser light scattering detector and refractive index detector (HPSEC-MALLS-RID) and high performance liquid chromatography with photo-diode array (HPLC-PDA) after 1-phenyl-3-methyl-5-pyrazolone (PMP) pre-column derivatization were used respectively to determine monosaccharide contents, molecular weights and monosaccharide compositions of polysaccharides in this study. The differences of SCF and SSF from ten producing areas were compared by principal component analysis (PCA) and hierarchical cluster analysis (HCA). Results showed that contents of fructose and glucose were similar between SCF and SSF. Molecular weight (Mw) of SCF polysaccharides was ranging from 1.561 × 10² to 6.599 × 10² kDa, and that of SSF polysaccharides was ranging from 8.524 × 10² to 1.7416 × 10³ kDa. Schisandra polysaccharides were mainly composed of mannose, galacturonic acid, glucose, galactose and arabinose. Based on PCA and HCA, SCF and SSF from ten different areas were classified into three categories. With great accuracy, sensitivity and stability, the methods established in this study had important reference value for quality evaluation, development and utilization of saccharide components in medicinal materials.     

Ultra high performance liquid chromatography with quadrupole time-of-flight tandem mass spectrometry and liquid chromatography with tandem mass spectrometry combined with chemometric analysis as an approach for the quality evaluation of Mume Fructus

Mume Fructus is an important traditional Chinese medicine that has been widely used in the treatment of intestinal diseases and asthma for thousands of years. In order to evaluate the quality of Mume Fructus in different processing methods, the main chemical components in Mume Fructus were investigated and a method was established for simultaneous quantification of organic acids of Mume Fructus. First, an optimized ultra-performance liquid chromatography-quadrupole-time of flight tandem-mass spectrometry method was used to identify the structures of main components in Mume Fructus. A total of 41 chemical compounds were identified, including 11 organic acids, 13 flavonoids, and three fatty acids. The contents of 11 organic acids in 18 batches of Mume Fructus from different processing methods were simultaneously determined by a liquid chromatography with tandem mass spectrometry method. The results of quantitative and hierarchical cluster analysis indicated that Mume Fructus under different processing methods were rich in the above 11 organic acids and the contents were obviously different. Taken together, the proposed quality evaluation method was fast and comprehensively reflects the content of the main chemical components in Mume Fructus under different processing methods, and provides a useful reference for the quality control and evaluation of Mume Fructus.     

Qualitative and quantitative analysis of multiple components for quality control of Deng‐Zhan‐Sheng‐Mai capsules by ultra high performance liquid chromatography tandem mass spectrometry method coupled with chemometrics

Deng‐Zhan‐Sheng‐Mai capsules are a well‐known traditional Chinese patent medicine that was developed in China for the treatment of ischemic stroke. Its quality control focuses on Erigerontis Herba but ignores the contributions of Ginseng Radix et Rhizoma, Schisandrae Chinensis Fructus, and Ophiopogonis Radix. To improve the quality standards for this medicine, this work reports the application of a systematic ultra high performance liquid chromatography tandem mass spectrometric method coupled with chemometrics. Three qualitative and quantitative parameters are established for the evaluation of quality: chemical profiling, the relationship between the contents of 18 compounds and the antioxidant activity, and chemometric analysis. A total of 55 compounds, including 20 phenolic acids, 10 flavonoids, 15 saponins, and 10 lignans, were identified. The method for the quantitative determination of the aforementioned 18 compounds was validated. The limit of quantification ranged from 0.13 to 9.60 ng/mL. The overall recoveries ranged from 95.31 to 103.54%. Hierarchical cluster analysis and principal component analysis were applied to the data of 18 components in ten batches of samples. Nine compounds, including scutellarin, 3,5‐O‐dicaffeoylquinic acid, 4,5‐O‐dicaffeoylquinic acid, ginsenoside Rb1, ginsenoside Re, ginsenoside Rg1, ophiopogonin D, schisandrin, and schisandrol B, are suggested as chemical markers for evaluating the quality.     

An integrated strategy of secondary metabolomics and glycomics to investigate multi-component variations in wine-processing of medicinal herbs and functional foods: A case study on Fructus Corni

Fructus Corni (FC), as a promising Chinese medicinal herb, has aroused considerable interest. Generally, FC needs to be processed according to the limited standard policy in China before clinical application, while the investigations on the specific processing methods (such as wine steaming or high-pressure wine steaming) are unclear. A comprehensive metabolomics strategy based on integrated non-targeted metabolomics and targeted glycomics in this paper was implemented to investigate the influences of the different processing technologies such as steaming, wine steaming, high-pressure steaming, high-pressure wine steaming, wine immersion, and wine stir-frying on FC, respectively. UHPLC-Q-TOF-MS/MS was employed for identifying and distinguishing the secondary metabolites. A total of 85 components were identified in all groups. The results of PCA score plots showed that the crude and processed samples had a complete separation, and wine steamed and high-pressure wine steamed samples could be a category, indicating that the two processed products had a similar quality. Multiple chromatography including HPLC (C₁₈)-PDA, HPLC (NH₂)-ELSD, and HPGPC-ELSD was used for determining the molecular weight distributions, the monosaccharide compositions of polysaccharides, and the contents of free monosaccharides and oligosaccharides. The results indicated that the content and composition of saccharides were different in crude and different processed FC. The polysaccharides were composed of fucose, arabinose, galactose, glucose, galacturonic acid, mannose and rhamnose, and the free monosaccharides were composed of fucose, arabinose, galactose, glucose, mannose, rhamnose and fructose in all FC samples. The PCA score plots of the glycomics indicated that the crude and high-pressure wine steamed FC could be a category, showing that the two groups had similar chemical compositions. Ultimately, the simulation processing experiments indicated that the transformation of morroniside, polysaccharides, oligosaccharides, fructose, and glucose to 5-HMF through the reactions of dehydration and deglycosylation was the potential mechanism of enhancing the effects by processing. Conclusionly, the saccharides should be investigated as thoroughly as the secondary metabolites, and the high-pressure wine steamed FC could be an alternative to wine steamed FC.     

Cardiac Muscle/Cell Membrane Chromatography-Offline-Liquid Chromatography/Mass Spectrometry Method to Identify Bioactive Components from Traditional Chinese Medicines

An offline analytical method combining cardiac muscle/cell membrane chromatography (CM/CMC) with liquid chromatography/mass spectrometry (LC/MS) to identify bioactive components from traditional Chinese medicines (TCMs) such as Schisandrae Chinensis Fructus (SCF) and Schisandrae Sphenantherae Fructus (SSF) was developed. The stationary phase of the CM/CMC system employed rat cardiac muscle cell membranes. Fractions retained by the CM/CMC column were collected and analyzed by LC/MS under optimum offline conditions. After evaluating the suitability and reliability of the CM/CMC-offline-LC/MS method using nifedipine and nitrendipine as standards, this method was applied for screening and identification of bioactive components from the extracts of SCF and SSF. The main compounds in both species retained by CM/CMC were deoxyschizandrin (DSD) and schisantherin A (STA) as identified by LC/MS. In vivo pharmacological experiments suggested that DSD and STA could significantly decrease the myocardial-infarct size in rats injured by myocardial ischemia–reperfusion. Our CM/CMC-offline-LC/MS method could be used as an effective alternative for screening multiple receptor-binding bioactive components in TCMs such as FSC and FSS used to remedy cardiac diseases and may be useful for drug discovery using medicinal herbs as lead compounds.     

益气通痹胶囊质量标准研究

采用薄层色谱法对益气通痹胶囊中黄芪、何首乌、五味子、赤芍、延胡索进行定性鉴别,采用高效液相色谱法测定了制剂中淫羊藿苷的含量. 所用薄层色谱具有鉴别特征,色谱斑点清晰,专属性强. 淫羊藿苷在0.55~3.30 μg范围内呈良好的线性关系(r =0.99996),平均回收率为98.4%,RSD为0.62 %. 所建立的定性和定量方法,操作简便可靠,专属性强,重现性好,能较全面反映该制剂内在质量,可作为益气通痹胶囊新药研发质量控制标准.     

Screening vasoconstriction inhibitors from traditional Chinese medicines using a vascular smooth muscle/cell membrane chromatography-offline-liquid chromatography-mass spectrometry

We developed an analytical method for screening vasoconstriction inhibitors from traditional Chinese medicines (TCMs) by combining vascular smooth muscle/cell membrane chromatography (VSM/CMC) with liquid chromatography-tandem mass spectrometry (LC-MS/MS). Primary cultured VSM cells from rat thoracic aortas were used for preparation of the stationary phase of the VSM/CMC column. Retention fractions from the VSM/CMC column were collected and then analyzed by LC-MS/MS under the optimized conditions offline. The suitability and reliability of the VSM/CMC-offline-LC-MS/MS method was assessed using nitrendipine and nifedipine as positive controls, and this method was then applied to screen vasodilator components from the extracts of Fructus Schisandrae Chinensis (FSC) and Fructus Schisandrae Sphenantherae (FSS). The major components from both species retained by VSM/CMC were identified as deoxyschizandrin (DSD) and schisantherin A (STA) by LC-MS/MS. Competition experiments indicated that DSD and nifedipine bound competitively to membrane receptors, while DSD and STA had partly overlapping binding sites on VSM-cell membranes. In vitro pharmacological trials confirmed that STA and DSD could dose-dependently relax the rat thoracic aortas pre-contracted by KCl. Our VSM/CMC-offline-LC-MS/MS method can be applied for screening vasoconstriction inhibitors from TCMs collected from FSC and FSS, and may be useful in the development of vasodilators from natural products.     

Application of characteristic fragment filtering with ultra high performance liquid chromatography coupled with high‐resolution mass spectrometry for comprehensive identification of components in Schisandrae chinensis Fructus

An integrated strategy of characteristic fragment filtering combined with target database screening based on ultra‐high‐performance liquid chromatography coupled with high‐resolution mass spectrometry was proposed for comprehensive profiling of components in Schisandrae chinensis Fructus. The strategy consisted of following five steps: (1) Representative standards were analyzed by ultra high performance liquid chromatography coupled with linear ion trap‐Orbitrap mass spectrometer for characteristic fragments and fragmentation rules of each structure type. (2) The raw data of 70% methanol extract was collected by ultra high performance liquid chromatography quadrupole time‐of‐flight tandem mass spectrometry. (3) The chemical components database that consisted of names, chemical formulas and structures of potential components in Schisandrae chinensis Fructus was established by summarizing previous literature to screen the collected liquid chromatography with mass spectrometry data and obtain matched compounds. (4) Characteristic fragments, literature, and reference standards were used to verify the matches. (5) Characteristic fragment filtering combined with online database querying was used to deduce potential new compounds. As a result, a total of 94 compounds were identified or characterized and 16 of them were potential new compounds. The study provided a reference for comprehensive characterization of ingredients in herbal medicine and formed the foundation for pharmacodynamic study of Schisandrae chinensis Fructus.     

Development of an ultra‐high‐performance liquid chromatography coupled with triple quadrupole mass spectrometry method for comparative pharmacokinetics of six triterpenoids in rat plasma and application to different forms of Phytolacca acinosa

Phytolacca acinosa is an herb for treatment of ascites and tumor. Two forms of P. acinosa, i.e. raw and vinegar‐processed herb, have been used in clinic. However, pharmacokinetic difference between the two forms of P. acinosa has not been fully understood. Herein, a comparative pharmacokinetic method based on liquid chromatography with tandem mass spectrometry was developed for quantification of six bioactive triterpenoids, including esculentoside H, esculentoside T, esculentoside A, esculentoside B, phytolaccagenic acid, and phytolaccagenin in rat plasma after oral administration of different forms of P. acinosa. Separation was performed on an Acquity BEH C₁₈ column (1.7 µm, 2.1 mm × 50 mm). The method was validated over a linear range of 2.0–5000 ng/mL. Intraday and interday bias were within ±5%. Besides, all triterpenoids were stable in plasma during different storage conditions. The described method was successfully applied to a comparative pharmacokinetic study of raw and vinegar‐processed P. acinosa in rats. Notably, double peak phenomenon for six triterpenoids of P. acinosa was observed for the first time. AUC_0→t and C_max values of esculentoside H, esculentoside T, phytolaccagenic acid, and phytolaccagenin were significantly lower in vinegar‐processed group than that of raw group, indicating the oral bioavailability of the four triterpenoids was decreased after vinegar processing.     

Solubilities of carbon dioxide in the eutectic mixture of levulinic acid (or furfuryl alcohol) and choline chloride

The solubilities of carbon dioxide (CO₂) in the renewable deep eutectic solvents (DESs) containing levulinic acid (or furfuryl alcohol) and choline chloride were determined at temperatures (303.15, 313.15, 323.15, and 333.15) K and pressures up to 600.0 kPa using an isochoric saturation method. The mole ratios of levulinic acid (or furfuryl alcohol) to choline chloride were fixed at 3:1, 4:1 and 5:1. Standard Gibbs free energy, dissolution enthalpy and dissolution entropy were calculated from Henry’s law constant of CO₂ in the DESs. Results indicated that levulinic acid based DESs are more effective to capture CO₂ than furfuryl alcohol based ones. The solubility of CO₂ in the DESs increased with increasing mole ratio of levulinic acid (or furfuryl alcohol) to choline chloride as well as pressure and decreased with increasing temperature.     

Comprehensive quality evaluation of Fructus Schisandrae using electrospray ionization ion trap multiple-stage tandem mass spectrometry coupled with chemical pattern recognition techniques

Electrospray ionization ion trap multiple-stage tandem mass spectrometry (ESI-MS(n)) was used to evaluate Fructus Schisandrae of similar species (Schisandra chinensis (Turcz.) Baill. fruits and Schisandra sphenanthera Rehd. et Wils. fruits) and different growth characteristics (color, shape, etc.). The application of chemical pattern recognition in the ESI-MS(n) data analysis was carried out by principal component analysis (PCA), hierarchical cluster analysis (HCA) and linear discriminant analysis (LDA). Then the antioxidant activity of different Fructus Schisandrae samples were determined by an LC-ESI-MS method and ferric reducing antioxidant power (FRAP) assay. Using the ESI-MS(n) method coupled with chemical pattern recognition analysis and correlated with the antioxidant activity evaluation, the two similar species were successfully distinguished, thus improving the therapeutic safety and effectiveness. The superior characteristics of Schisandra chinensis (Turcz.) Baill. fruits were obtained and made the selection and breeding of Chinese medicine materials more scientific. This study indicates that ESI-MS(n) is a valuable tool for the authentication of botanical origin and can also be useful for the quality control of Chinese medicinal herbs.     

Direct analysis of herbal powders by pipette-tip electrospray ionization mass spectrometry

Conventional electrospray ionization mass spectrometry (ESI-MS) is widely used for analysis of solution samples. The development of solid-substrate ESI-MS allows direct ionization analysis of bulky solid samples. In this study, we developed pipette-tip ESI-MS, a technique that combines pipette tips with syringe and syringe pump, for direct analysis of herbal powders, another common form of samples. We demonstrated that various herbal powder samples, including herbal medicines and food samples, could be readily online extracted and analyzed using this technique. Various powder samples, such as Rhizoma coptidis, lotus plumule, great burdock achene, black pepper, Panax ginseng, roasted coffee beans, Fructus Schisandrae Chinensis and Fructus Schisandrae Sphenantherae, were analyzed using pipette-tip ESI-MS and quality mass spectra with stable and durable signals could be obtained. Both positive and negative ion modes were attempted and various compounds including amino acids, oligosaccharides, glycosides, alkaloids, organic acids, ginosensides, flavonoids and lignans could be detected. Principal component analysis (PCA) based on the acquired mass spectra allowed rapid differentiation of closely related herbal species.     

Investigation of phase equilibria of levulinic acid distribution between aqueous phase to organic phase by Aliquat 336 in different modifiers

The extraction of levulinic acid by tricaprylmethylammonium chloride (Aliquat 336) dissolved in five alcohols solvents (isoamyl alcohol, hexan-1-ol, octan-1-ol, nonan-1-ol, decan-1-ol) and five esters solvents (dimethyl phthalate, dimethyl adipate, dimethyl succinate, dimethyl glutarate, diethyl carbonate), two ketones (diisobutyl ketone (DIBK), methyl isobutyl ketone (MIBK)) were investigated to understand effect of modifier on levulinic acid extraction. In addition to these Aliquat 336 + modifier system, the experiments were done also with single solvents. All measurements were carried out T = 298.15 K. Organic solutions of Aliquat 336 are being used increasingly to separate organic acids from aqueous mixture solutions by reactive extraction. The extent to which the organic phase may be loaded with levulinic acid is explained as a loading ratio, Z_Z, extraction efficiency E and, distribution coefficients K_D were calculated. The maximum extraction efficiency was obtained value of 72.1 for isoamyl alcohol. The extraction equilibrium constant, K_E, has been calculated for each modifier. Furthermore, Freundlich, Langmuir, and LSER model equations have been obtained for experimental data of alcohols.     

Simultaneous quantification of atractyloside and carboxyatractyloside in rat plasma by LC‐MS/MS: Application to a pharmacokinetic study after oral administration of Xanthii Fructus extract

Xanthii Fructus is extensively used as an herbal medicine. Ingestion of this herb is associated with severe hepatotoxicity and nephrotoxicity. Atractyloside and carboxyatractyloside are two dominative toxic constituents in Xanthii Fructus. However, their pharmacokinetic study is lacking. In this study, a novel high‐performance liquid chromatography‐tandem mass spectrometry method was developed to simultaneously quantify the rat plasma concentrations of atractyloside and carboxyatractyloside. After protein precipitation, the analytes were chromatographic separated on a ZORBAX Eclipse Plus column (2.1 × 150 mm id, 5 µm) under gradient elute. In the negative electrospray ionization mode, the transitions at m/z 725.3→645.4 for atractyloside, m/z 769.3→689.4 for carboxyatractyloside, and m/z 479.2→121.1 for paeoniflorin (the internal standard) were acquired by multiple reaction monitoring. This analytical method showed good linearity over 1–500 ng/mL for atractyloside and 2–500 ng/mL for carboxyatractyloside with acceptable precision and accuracy. No matrix effect, instability and carryover occurred in the analysis procedure. The extraction recoveries were greater than 85.0%. This method was applied to a preliminary pharmacokinetic study by orally administering Xanthii Fructus extract (9 g/kg) to rats, which was useful to evaluate the role of these two compounds in Xanthii Fructus‐induced toxicity.     

Characterization and discrimination of raw and vinegar‐baked Bupleuri radix based on UHPLC‐Q‐TOF‐MS coupled with multivariate statistical analysis

Bupleuri Radix is a commonly used herb in clinic, and raw and vinegar‐baked Bupleuri Radix are both documented in the Pharmacopoeia of People's Republic of China. According to the theories of traditional Chinese medicine, Bupleuri Radix possesses different therapeutic effects before and after processing. However, the chemical mechanism of this processing is still unknown. In this study, ultra‐high‐performance liquid chromatography with quadruple time‐of‐flight mass spectrometry coupled with multivariate statistical analysis including principal component analysis and orthogonal partial least square‐discriminant analysis was developed to holistically compare the difference between raw and vinegar‐baked Bupleuri Radix for the first time. As a result, 50 peaks in raw and processed Bupleuri Radix were detected, respectively, and a total of 49 peak chemical compounds were identified. Saikosaponin a, saikosaponin d, saikosaponin b₃, saikosaponin e, saikosaponin c, saikosaponin b₂, saikosaponin b₁, 4′′‐O‐acetyl‐saikosaponin d, hyperoside and 3′,4′‐dimethoxy quercetin were explored as potential markers of raw and vinegar‐baked Bupleuri Radix. This study has been successfully applied for global analysis of raw and vinegar‐processed samples. Furthermore, the underlying hepatoprotective mechanism of Bupleuri Radix was predicted, which was related to the changes of chemical profiling.     

Rapid identification of chemical constituents in Hugan tablets by ultra-performance liquid chromatography-quadrupole-exactive orbitrap mass spectrometry

Hugan tablet is a Chinese medicine preparation. It is composed of Bupleuri Radix, Artemisiae Scopariae Herba, Isatidis Radix, Schisandrae Chinensis Fructus, Suis Fellis Pulvis, and Vigna radiata L. It has the effects of dispersing stagnated liver qi, strengthening the spleen and eliminating food to be used for the treatment of chronic hepatitis and early cirrhosis. However, the chemical composition of Hugan tablet is complex and not fully understood, which hampers the research in pharmacology. In this study, a reliable method for the rapid analysis and identification of the chemical components in Hugan tablet by their characteristic fragments and neutral losses using ultra-performance liquid chromatography-quadrupole-exactive orbitrap mass spectrometry was developed. A total of 144 chemical components were tentatively identified, including 57 organic acids, 19 flavonoids, 23 alkaloids, 18 lignans, 7 saponins, and 20 others. These components may be the active ingredients of Hugan tablet. The established method can systematically and rapidly analyze the chemical components in Hugan tablet, which provides a basis for the pharmacodynamic substance study and is meaningful for the quality control of Hugan tablet.     

Dehydration of glucose into 5-hydroxymethylfurfural in SO_3H-functionalized ionic liquids

The continuous dehydration of D-glucose into 5-hydroxymethylfurfural（HMF） was carried out under mild conditions,using SO3H-functionalized acidic ionic liquids as catalysts and H2O-4-methyl-2-pentanone（MIBK） biphasic system as solvent.High glucose conversion of 97.4% with HMF yield of 75.1%was obtained at 120 8C for 360 min,also,small amounts of levulinic acid（LA） and formic acid were generated.Generally,the dosage of catalyst and the initial content of glucose influenced the reaction significantly; the HMF selectivity decreased with the excessive elevation of temperature and prolonging of time; and water content in the system had a negative effect on the reaction.The ionic liquid catalyst could be recycled and exhibited constant activity for five successful runs.This paper provided a new strategy for HMF production from glucose.     

A simple liquid chromatography coupled with tandem mass spectrometry approach for the simultaneous quantification of thirteen compounds in rats following oral administration of raw and processed Fructus Xanthii: Application in a comparative pharmacokinetic study

A simple and sensitive analysis using ultra high performance liquid chromatography with a tandem mass spectrometric system operated in selected reaction monitoring mode was developed for the determination of 11 phenolic acids, atractyloside, and carboxyatractyloside in rat plasma. The two classes of analytes were then separated on a Waters ACQUITY? UPLC HSS T3 column (50 mm × 2.1 mm, 1.8 µm) using gradient elution with a mobile phase of 0.2% formic acid in water containing 10 mM ammonium acetate and methanol. Detection was accomplished by selected reaction monitoring scanning via an electrospray source operating in negative ionization mode. The calibration curve was linear (R² = 0.990) over a concentration range of 1.20–3500 ng/mL, while the validated lower limit of quantification was 1.20 ng/mL. The precision varied from 0.84 to 4.62%, and the accuracy varied within ±5%. The method proved robust with sample freezing and thawing and with short‐ and long‐term sample storage. The established method was used for simultaneous quantification and was successfully used for the first time for the pharmacokinetic evaluation of 13 compounds after the intragastric administration of raw and processed Fructus Xanthii in rats. The results indicated that processing affects the absorption and metabolism of Fructus Xanthii extract. Importantly, the results also indicated the importance of processing for the clinical application of traditional Chinese medicine.     

Influence of the pH Value on the Hydrothermal Degradation of Fructose

The hydrothermal treatment of sugars features a promising technology for the production of fine and platform chemicals from renewable resources. In this work the hydrothermal decomposition of fructose was studied in a buffered medium at a pH range between 2.2 and 8.0. It is demonstrated that at lower pH values mainly 5-hydroxymethylfurfural (HMF), levulinic acid and humin are generated, while lactic acid and acetic acid are produced at higher pH values. The work shows that the use of moderate acidic conditions may have advantages for the hydrothermal HMF production over the use of strongly acidic conditions, as especially the degradation into levulinic acid is suppressed. Besides, this study deals with a rather complex reaction network, hence limitations and need for adaption of the kinetic model are discussed.