Differentiation of isomeric chalcone and dihydroflavone using liquid chromatography coupled with hydrogen-deuterium exchange tandem mass spectrometry (HDX-MS/MS): An application for flavonoids-focused characterization of Snow chrysanthemum.

Although the co-occurrences of isomeric chalcones and dihydroflavones widely appear in medicinal plants, the differentiation of such isomerism seldom succeeds using MS/MS, attributing to totally identical MS/MS spectra. Here, efforts were paid to pursue an eligible tool allowing to address the technical challenge. Being inspired by that one more proton signal is observed in 1H NMR spectrum of isoliquiritigenin than liquiritigenin when employing DMSO­d6 as solvent, hydrogen-deuterium exchange (HDX)-MS/MS was evaluated towards differentiating isomeric chalcones and dihydroflavones through replacing H2O with D2O to prepare the mobile phase. As a result, differences were observed for either MS1 or MS2 spectrum when comparing two pairs of isomers, such as liquiritigenin vs. isoliquiritigenin and liquiritin vs. isoliquiritin, because the isomeric precursor and fragment ion species owned different amounts of hydroxyl protons and those reactive protons could be partially or completely substituted by deuterium protons at the exposure in D2O to result in n × 1.006 mass increments. Moreover, utmost four hydrogen/deuterium exchanges occurred for a single glucosyl moiety. Thereafter, HDX-MS/MS was applied to characterize the flavonoids of Snow chrysanthemum, a precious edible herbal medicine that is rich in isomeric chalcones and dihydroflavones. Through paying special attention to the deuterium labeling styles of (de)protonated molecules as well as those featured fragment ions, five pairs of isomeric chalcones and dihydroflavones were confirmatively differentiated, in addition to that 28 flavonoids were structurally annotated by applying those well-defined mass fragmentation rules. Hence, this study offered an in-depth insight towards the flavonoids-focused characterization of Snow chrysanthemum, and more importantly, HDX-MS/MS is a superior tool to differentiate, but not limited to, isomeric chalcones and dihydroflavones.

A quantitative chemomics strategy for the comprehensive comparison of Murraya paniculata and M. exotica using liquid chromatography coupled with mass spectrometry.

Murrayae Folium et Cacumen (MFC) is a traditional Chinese medicine (TCM) derived from two plant species, Murraya exotica L. and Murraya paniculata (L.) Jack, as recorded in the Chinese Pharmacopoeia. However, there is no research available on the comprehensive analysis and comparison of the chemical constituents of these two species. In the present study, an integrated LC-MS-based quantitative metabolome strategy was proposed to conduct a comprehensive and in-depth qualitative and quantitative analysis and comparison of the chemome of M. exotica and M. paniculata. Firstly, the universal chemical information of two plants was obtained by quadrupole-time-of-flight mass spectrometry (Q-TOF-MS) combined with hybrid triple quadrupole-linear ion trap mass spectrometry (Qtrap-MS). Subsequently, a UNIFI in house database, the proposed fragmentation patterns, and a quantitative structure chromatographic retention relationship (QSRR) model were integrated for the rapid, comprehensive, and accurate structural elucidation of the chemical constituents of these two species. Thirdly, a large-scale quantitation method was established using scheduled multiple reaction monitoring mode (sMRM) and 76 primary components were selected as quantitative markers for the method validation. The obtained dataset was then subjected for multivariate statistical analysis to comprehensive comparison of these two plants. As a result, a total of 209 and 212 compounds were identified from M. exotica and M. paniculata, respectively. Among them, 103 common constituents were disclosed in both plants. The multivariate statistical analysis and absolute quantitative analysis revealed noticeable differences in the contents of specific chemical constituents between these two plants. The higher quantity constituents in M. exotica are 7-methoxycoumarins, while polymethoxylated flavonoids are the major constituents in M. paniculata. The common compounds accounted for approximately 80 % of the quantitative components in both plants, which provides a theoretical basis for their common use as the official source of MFC. In sum, the established quantitative chemomics strategy supplies an effective means for comprehensive chemical comparison of multi-source TCMs.

Integrated strategy facilitates rapid in-depth chemome characterization of traditional Chinese medicine prescriptions: Shengbai oral liquid as a case.

Chemome characterization is the prerequisite for either therapeutic mechanism clarification or quality control of traditional Chinese medicine prescriptions (TCMPs). Liquid chromatography-mass spectrometry/mass spectrometry (LC-MS/MS) currently serves as the most popular analytical tool; however, chemome characterization is still challenged by MS/MS spectral acquisition and post-acquisition data processing. Here, an integrated strategy was proposed for in-depth chemome clarification of Shengbai oral liquid (SBOL). Gas phase ion fractionation with staggered mass ranges was demonstrated to be the superior acquisition method regarding MS2 spectrum coverage in this study, and narrower mass range further advanced coverage. To facilitate information extraction, all ingredient materials were measured in parallel to form an in-house library, where each MS1 -MS2 item generated a square mass-to-charge ratio (m/z) frame to capture the tagged identity and each chemical family produced a pentagon frame for mass defect features to accomplish chemical analogs-targeted quasi-molecular ion extraction. Square m/z frame imprinting captured 355 identities, while mass defect frames extracted 275 compounds. Attributing to comprehensive MS2 spectrum acquisition and efficient data processing, 355 components were captured and tentatively identified, resulting in a clarified chemical composition for SBOL. Therefore, the proposed strategy should be meaningful for the chemome characterization of TCMPs.

[Chemical constituents of diterpenoids from Boswellia carterii].

This paper explored the chemical constituents of Boswellia carterii by column chromatography on silica gel, Sephadex LH-20, ODS column chromatography, and semi-preparative HPLC. The structures of the compounds were identified by physicochemical properties and spectroscopic data such as infrared radiation(IR), ultra violet(UV), mass spectrometry(MS), and nuclear magnetic resonance(NMR). Seven diterpenoids were isolated and purified from n-hexane of B. carterii. The isolates were identified as(1S,3E,7E,11R,12R)-11-hydroxy-1-isopropyl-4,8,12-trimethyl-15-oxabicyclo[10.2.1]pentadeca-3,7-dien-5-one(1),(1R,3S,4R,7E,11E)-4,8,12,15,15-pentamethyl-14-oxabicyclo[11.2.1]hexadeca-7,11-dien-4-ol(2), incensole(3),(-)-(R)-nephthenol(4), euphraticanoid F(5), dilospirane B(6), and dictyotin C(7). Among them, compounds 1 and 2 were new and their absolute configurations were determined by comparison of the calculated and experimental electronic circular dichroisms(ECDs). Compounds 6 and 7 were obtained from B. carterii for the first time.

Exploring the active components and potential mechanisms of Rosa roxburghii Tratt in treating type 2 diabetes mellitus based on UPLC-Q-exactive Orbitrap/MS and network pharmacology.

BACKGROUND: Type 2 diabetes mellitus (T2DM) is a global disease with growing prevalence that is difficult to cure. Rosa roxburghii Tratt is an edible and medicinal plant, and modern pharmacological studies have shown that it has potential anti-diabetic activity. This is the first study to explore the active components and potential mechanisms of Rosa roxburghii Tratt fruit for treating T2DM based on UPLC-Q-Exactive Orbitrap/MS and network pharmacology. METHODS: The active components of Rosa roxburghii Tratt fruit were obtained from UPLC-Q-Exactive Orbitrap/MS analysis and retrieval in the SciFinder, PubMed, Web of Science, and CNKI databases. The potential targets of the active components were obtained from the SwissTargetPrediction and PharmMapper databases. The disease targets for T2DM were obtained from GeneCards, OMIM, TTD, DisGENent, and GEO databases. The intersection of the two datasets was used to obtain the potential targets of Rosa roxburghii Tratt fruit against T2DM. The target protein interaction network was constructed using the String database and Cytoscape software. The R software ClusterProfiler package was used for target enrichment analysis and the Cytoscape CytoNCA plug-in was used to screen core targets. Molecular docking and result visualization were performed using PyMOL and Autodock Vina software. RESULTS: We obtained 20 bioactive ingredients, including alphitolic acid, quercetin, and ellagic acid, as well as 13 core targets, such as AKT1, TNF, SRC, and VEGFA. All bioactive ingredients in Rosa roxburghii Tratt fruit were active against T2DM-related therapeutic targets. Rosa roxburghii Tratt fruit may play a therapeutic role in T2DM by regulating the PI3K/AKT, RAS, AGE-RAGE, and other signaling pathways. CONCLUSIONS: This study explored the active components and potential mechanisms of Rosa roxburghii Tratt fruit in the treatment of T2DM, laying the foundation for a further experimental study based on pharmacodynamic substances and their mechanisms of action.

Two-dimensional code enables visibly mapping herbal medicine chemome: an application in Ganoderma lucidum.

BACKGROUND: Chemical profile provides the pronounced evidence for herbal medicine (HM) authentication; however, the chemome is extremely sophisticated. Fortunately, two-dimensional (2D) code, as a quick response means, is conceptually able to store abundant information, exactly fulfilling the chemical information storage demands of HMs. METHODS: We here attempted to denote both MS[Formula: see text] and MS[Formula: see text] dataset of HM with a single 2D-code chart. Measurement of Ganoderma lucidum that is one of the most famous HMs with LC-MS/MS was employed to illustrate the "coding-decoding" workflow for the conversion amongst MS/MS dataset, 2D-code, and chemical profile, and to evaluate the applicability as well. After data acquisition, and m/z value of each deprotonated molecular signal was divided into integer and decimal portions, corresponding to x and y coordinates of 2D-plot, respectively. On the other side, m/z values of all its fragment ions were exactly assigned to serial x values sharing an identical y value being equal to the precursor ion. 2D-code was thereafter produced by plotting these defined dots at a 2D-chart. Regarding a given 2D-code map, the entire chart (x coordinate: 0-600; y coordinate: 0-600) was fragmented into two regions by the line of y=x. MS[Formula: see text] spectral signals always located below the line, whereas all fragment ions lay at the left zone. After extracting information from the edges of each square frame, m/z values of both precursor ion and fragment ions could be harvested and putatively deciphered to a compound through applying some empirical mass fragmentation rules. RESULTS: The entire code of Ganoderma lucidum fruit bodies therefore corresponded exactly to a compound set. The elution program, even the employment of direct infusion, couldn't significantly impact the code, and dramatical differences occurred between different species and amongst different parts of Ganoderma lucidum as well. Not only ganoderic acid cluster but also certain primary metabolites served as the diagnostic compounds towards species differentiation. CONCLUSION: 2D-code might be a meaningful, practical visual way for rapid HM recognition because it is convenient to achieve the conversion amongst MS/MS dataset, 2D-barcode plot, and the chemome.

Anti-inflammatory flavonoid derivatives from the heartwood of Dalbergia odorifera T. Chen.

Two pairs of flavonoid enantiomers (1a/1b and 2a/2b) together with three known analogues (3-5) were isolated from the heartwood of Dalbergia odorifera T. Chen. Their structures were elucidated by extensive spectroscopic analysis (1 D and 2 D NMR, UV, IR, and HRMS) and experimental and calculated ECD data. Compound 2 features an unusual 2-methyl-3(2H)-furanone moiety forming the C-ring of flavonoid, and its putative biosynthetic pathway is also proposed. Compounds 3‒5 exhibited significant inhibition of nitric oxide production in lipopolysaccharide-stimulated RAW264.7 cells with IC50 values of 14.7 ± 0.3 µM, 40.2 ± 1.1 µM, and 3.2 ± 0.1 µM, respectively.

[Chemome profiling of Qijiao Shengbai Capsules by UPLC-IT-TOF-MS].

Qijiao Shengbai Capsules(QJ) are a common Miao medicine serving as an adjuvant cancer therapy in clinical practice.QJ consists of seven medicinal materials such as Astragalus membranaceus and Lespedeza buergeri.Its chemical components have not been clarified and the quality control needs to be improved.In this study, LC-IT-TOF-MS was used to comprehensively collect MS~1 and MS~2 fragment information of QJ and rapidly identify the chemical compositions.The chromatographic separation was performed on the Capcell core ADME column(2.1 mm×150 mm, 2.7 µm) with 0.1% formic acid aqueous solution(A) and acetonitrile(B) as mobile phases for gradient elution.High-resolution mass spectrometric information was obtained by scanning in the positive and negative ion ESI modes.A total of 107 compounds were structurally identified according to the deduced MS fragmentation patterns and comparison with standards and data reported in the literature, including 54 flavonoids, 16 phthalides, 13 alkaloids, 12 phenolic acids, 7 saponins, 2 coumarins, 2 condensed tannins, and 1 purine.This study clarified the chemical composition of QJ and provided references for the improvement of its quality standards and the elucidation of its medicinal substances.

[Sesquiterpenoids from Aquilariae Lignum Resinatum].

Eight sesquiterpenoids were isolated from petroleum ether extract of Aquilariae Lignum Resinatum by various column chromatography techniques including silica gel, ODS, and semi-preparative HPLC. Their structures were identified on the basis of physicochemical properties, UV, IR, MS, and NMR spectroscopic data as(4S,5S,7R,10S)-5,7-dihydroxy-11-en-eudesmane(1),(7R,10S)-eudesma-4-en-11,15-diol(2),(2R,4S,5R,7R)-2-hydroxyeremophila-9,11-dien-8-one(3), 7α-H-9(10)-ene-11,12-epoxy-8-oxoeremophilane(4),(+)-9ß,10ß-epoxyeremophila-11(13)-en(5), 4(14)-eudesmene-8α,11-diol(6), 12,15-dioxo-selina-4,11-dien(7), and 2ß,8 aα-dihydroxy-11-en-eremophilane(8). Compounds 1 and 2 are new compounds, and their absolute configurations were determined by calculating ECD. Compounds 1, 4, and 6-8 could significantly improve taurocholic acid(TCA)-induced gastric mucosal GES-1 cell injury at a concentration of 20 µmol·L~(-1), and the cell protection rates were 23.51%±2.79%, 16.10%±1.25%, 24.45%±4.89%, 17.48%±2.93%, and 21.44%±2.39%, respectively.

[Rapid chemome characterization of Pien-Tze-Huang by DI-MS/MS~(ALL)].

Pien-Tze-Huang, one of the most famous and widely used Chinese medicinal prescriptions in China, consists of Notoginseng Radix et Rhizoma, Bovis Calculus, Fel Serpentis, and Moschus.The prescription can clear heat and remove toxin, cool blood and resolve blood stasis, and relieve swelling and pain.Characterizing the chemical composition can facilitate the construction of the quality standard and the research on the effective compounds and action mechanism of Pien-Tze-Huang.Therefore, this study used direct infusion(DI)-MS/MS~(ALL) method to rapidly and accurately reveal the chemical composition of Pien-Tze-Huang.The principle of chemical composition profiling of Chinese medicinal prescriptions lies in the MS~1-MS~2 dataset construction, followed by structural annotation based on MS/MS spectra and summarizing of mass fragmentation pathways.MS/MS~(ALL) owns unique mass spectrometric separation ability via applying gas phase fractionation which enables MS~1 ion cohort successively enter the collision cell and acquire MS~2 spectrum for each precursor ion current with a width of m/z=1.Because DI can provide desired measurement time, MS/MS~(ALL) is able to acquire MS~2 spectrum for each compound individually except for the compounds which share identical nominal molecular weight, even isomers.A total of 52 compounds were identified in Pien-Tze-Huang, including 16 saponins, 24 bile acids, 9 fatty acids, 2 saccharides, and 1 other compound.DI-MS/MS~(ALL) can simultaneously identify the compounds with different polarities in a short time, which is superior to LC-MS.This study provides a powerful tool for the rapid chemome profiling of Chinese medicinal prescriptions.

Integrated strategy for widely targeted metabolome characterization of Peucedani Radix.

Herbal medicines (HMs) are widely recognized as extremely complicated matrices, resulting in a great challenge for the existing analytical approaches to characterize the widely targeted metabolome. The primary obstacles include high-level structural diversity, broad concentration range, large polarity span, insufficient authentic compounds and frequent occurrences of isomers, even enantiomers. Here, we aimed to propose an integrated strategy being able to circumvent the technical barriers, and a well-known HM namely Peucedani Radix was employed to illustrate and justify the applicability. Regarding qualitative analysis, the hydrophilic metabolites were detected with HILIC-predictive multiple-reaction monitoring mode, and structurally identified by matching predefined identities with authentic compounds or information archived in relevant databases. After RPLC-MS/MS measurement, full collision energy ramp-MS2 spectrum in combination with quantum structural calculation was applied to confirmatively identify those less polar components, mainly angular-type pyranocoumarins (APs). For quantitative analysis, achiral-chiral RPLC/HILIC was configured for chromatographic separations because the analytes spanned a large polarity range and involved many enantiomers. A quasi-content concept was employed for comprehensively relative quantitation through constructing a so-called universal metabolome standard (UMS) sample and building calibration curves by assaying serial diluted UMS solutions. Consequently, high-confidence structural annotation and relatively quantitative analysis were achieved for 103 compounds, in total. After multivariate statistical analysis, some APs, e.g., (3'S)-praeruptorin A, (3'S)-praeruptorin B, (3'S)-praeruptorin E, as well as several primary metabolites were screened out as the prominent contributors for inter-batch variations. Together, current study shows a promising strategy enabling widely targeted metabolomics of, but not limited to, HMs.

2-(2-phenylethyl)chromone-enriched extract of the resinous heartwood of Chinese agarwood (Aquilaria sinensis) protects against taurocholic acid-induced gastric epithelial cells apoptosis through Perk/eIF2α/CHOP pathway.

BACKGROUND: Injury of gastric epithelial cells is one of the most important pathological features of bile reflux gastritis. Chinese agarwood (the resinous heartwood of Aquilaria sinensis) has been used to treat stomach problems for thousands of years in China. However, the pathological mechanism of epithelial cells death induced by bile acids and the therapeutic target of Chinese agarwood for improving bile reflux gastritis have not yet been fully clarified. PURPOSE: This study aimed to investigate the pro-apoptotic effect of taurocholic acid (TCA) by regulating the ER stress pathway. Moreover, the role of Chinese agarwood 2-(2-phenylethyl)chromone-enriched extract (CPE) to inhibit gastric epithelial cell death induced by TCA was also been demonstrated. METHODS: We adopted human gastric epithelial GES-1 cells to explore the mechanism of TCA-induced cell death in vitro. Then the cell viability, apoptosis rate, and protein expressions were evaluated to explore the protective effects of CPE on GES-1 cells by TCA injury. The therapeutic effect of CPE on bile reflux gastritis was further confirmed by the bile reflux mice in vivo. RESULTS: Our results demonstrated that TCA activated GES-1 cell apoptosis by increased cleavage of caspase-7 and PARP. Further experiments showed that TCA up-regulated endoplasmic reticulum (ER) stress, subsequently triggered the apoptosis of the epithelial cells. Our research explored that CPE is the main effective fraction in Chinese agarwood by preventing the TCA-induced gastric epithelial cell injury. CPE effectively suppressed GES-1 cell apoptosis activated by TCA through inhibiting Perk/eIF2α/CHOP pathway. The anti-apoptotic effect of CPE on gastric mucosa had also been confirmed in vivo. Moreover, the main effective components in CPE corresponding to the protection of epithelial cells were also been identified. CONCLUSION: Our finding suggested that CPE recovered the TCA-induced epithelial cell apoptosis by mediating the activation of ER stress, which explored potential medicine to treat bile reflux gastritis.

High-level structural analysis of proanthocyanidins using full collision energy ramp-MS2 spectrum.

Proanthocyanidins (PACs) refer to a group of polyphenols consisting of flavan-3-ol units, and are ubiquitously distributed in fruits, vegetables, nuts and grains. PACs possess high-level structural diversity because of the fickle linkage manners amongst units, the polymerization degree and stereoisomeric forms, thus leading to a great challenge for structural analysis. Although LC-MS/MS currently serves as the workhorse to profile PACs in complicated matrices, it's still challenging to achieve confirmatively structural annotation even employing the cutting-edged high-resolution MS/MS techniques, and the key technical obstacle lies at isomeric discrimination. To pursue as many auxiliary structural clues as possible, full collision energy ramp-MS2 (FCER-MS2) spectrum was conceptually designed here to involve all mass fragmentation behaviors of a given compound, such as m/z, optimal collision energy (OCE) and the maximal relative ion intensity (RIImax) aiming to advance the structural annotation confidences of PACs through reliably differentiating isomers. Thirteen authentic compounds were collected to mine relationships between chemical structures and FCER-MS2 spectra that were correlated by three progressive steps: (1) recording MS/MS spectrum by LC-Q-TOF-MS; (2) proposing mass fragmentation pathways to assign those obvious fragment ion species; and (3) acquiring breakdown graph for each concerned fragment ion species by programming online energy-resolved mass spectrometry to compose FCER-MS2 spectrum. Afterwards, the rules were applied for PACs-focused chemical characterization of a medicinal herb namely Indigofera stachyodes (Chinese name: Xuerenshen), and as a result, 22 PACs were captured and more importantly, isomerically identified by deciphering FCER-MS2 spectra. Therefore, FCER-MS2 spectrum provides a promising way to achieve in-depth isomeric discrimination of, but not limited to, PACs.

Full Collision Energy Ramp-MS2 Spectrum in Structural Analysis Relying on MS/MS.

Albeit frequently being overlooked, MS2 spectrum variation against collision energy (CE) implies auxiliary structural clues for m/z values. Online energy-resolved MS (ER-MS) provides the opportunity to acquire the trajectory of ion intensity against CE for any fragment ion of interest, thus exactly offering the desired momentum to empower the conventional MS2 spectrum at a certain CE forward to a full-CE ramp MS2 spectrum (FCER-MS2). Efforts were made here to construct an FCER-MS2 spectrum and to evaluate its potential toward structural analysis. Flavonoids were employed as a proof of concept. MS2 spectra of 76 compounds were recorded by LC-Q-Exactive-MS, and online ER-MS was subsequently programmed using LC-Qtrap-MS to build a breakdown graph for each obvious fragment ion. After defining the greatest value amongst all regressive apices as 100%, the normalized breakdown graphs comprised an FCER-MS2 spectrum for each compound. The FCER-MS2 spectrum contained the MS2 spectrum at any CE as well as optimal CE (OCE) and maximal relative ion intensity (RIImax) of each fragment ion. Except the pronounced isomeric discrimination potential, either OCE or RIImax reflected certain structural properties, such as aglycone, glycosidic bond, and hydroxy, methoxy, and glycosyl substituents. These rules were subsequently applied for flavonoid-focused characterization of a famous herbal medicine, namely Scutellariae Radix, and high-level structural annotation was accomplished for 75 flavonoids. Above all, the FCER-MS2 spectrum includes m/z, OCEs, and RIImax features, thus facilitating confidence-advanced structural analysis.

[Research on in vivo metabolites of Longxue Tongluo Capsules by liquid chromatography coupled with hybrid ion trap/time-of-flight mass spectrometry].

Longxue Tongluo Capsules(LTC) has good efficacy against blood stasis syndrome during the recovery period of ischemic stroke. Its main active ingredient is the phenolic extract of Chinese dragon's blood. In our previous study, the primary mass fragmentation pathways of phenolic derivatives from LTC were clarified. Herein, the metabolites in rat plasma were characterized following the oral administration of loureirin A and loureirin C using liquid chromatography coupled with hybrid ion trap/time-of-flight mass spectro-metry(LC-IT-TOF-MS), with 18 and 55 metabolites identified, respectively. On this basis, with the help of the obtained accurate molecular weight, characteristic fragment ions, reference comparison, combined with LTC database and natural products database self-created in our group, 18 prototypes and 106 metabolites were tentatively identified in rat plasma after oral gavage of LTC at a dose of 500 mg·kg~(-1). Glucuronidation, sulfonation, and methylation were major biotransformation pathways of LTC. This study preliminarily clarified the LTC constituents absorbed into blood and laid the foundation for clarifying the effective substances of LTC.

[Condensed tannins from roots of Indigofera stachyodes].

Eleven condensed tannins were isolated from the roots of Indigofera stachyodes by various column chromatography techniques including silica gel, octadecyl silica(ODS), Sephadex LH-20, and semi-preparative high performance liquid chromatography(HPLC). These compounds were identified on the basis of physicochemical properties, nuclear magnetic resonance(NMR) and mass spectrometry(MS) data as stachyotannin A(1), epicatechin-(2ß→O→7,4ß→8)-epiafzelechin-(4ß→8)-catechin(2), cinnamtannin D1(3), cinnamtannin B1(4), epicatechin-(2ß→O→7,4ß→8)-epiafzelechin-(4α→8)-epicatechin(5), gambiriin C(6), proanthocyanidin A1(7), proanthocyanidin A2(8), aesculitannin B(9), proanthocyanidin A4(10), and procyanidin B5(11). Compound 1 is a new compound. Compounds 2-11 were isolated from Indigofera for the first time. Furthermore, compounds 1, 2, and 4-11 showed inhibitory effects on thrombin-induced ATP release in platelets.

[Rapid chemome profiling of Cistanche salsa using DI-MS/MS~(ALL)].

The current study aims to rapidly and comprehensively profile the chemical composition of Cistanche salsa using direct infusion coupled with MS/MS~(ALL)(DI-MS/MS~(ALL)). The C. salsa extract was directly imported into electrospray ionization(ESI) source of quadrupole time-of-flight(Q-TOF) mass spectrometer with an infusion pump at a flow rate of 10 µL·min~(-1). Acquisition program was applied under negative ionization polarity to collect one MS~1 spectrum(m/z 50-1 200), followed by 1 150 MS~2 spectra with precursor isolation window(m/z 1) amongst mass range m/z 50-1 200. After each MS~2 spectrum was matched to its precursor ion, putative identification was conducted through matching mass spectral data with literature and database. A total of 31 components were identified from C. salsa, including 9 phenylethanoid glycosides, 2 iridoids, 4 saccharides, 9 organic acids, and 7 other compounds, similar to those from C. tubulosa and C. deserticola. In conclusion, DI-MS/MS~(ALL), a facile and reliable analytical tool, can be employed for qualitative analysis of chemical constituents in C. salsa. The research offers a promising strategy to achieve rapid chemome profiling of herbal medicine and provides an alternative source of Cistanches Herba.

[Isomeric discrimination of kaempferol versus luteolin by online energy-resolved mass spectrometry].

Isomers are widely distributed in Chinese herbal medicines,and can be discriminated by energy-resolved mass spectrometry( ER-MS). However,ER-MS was performed through direct injection of reference compounds with syringe pump,which encountered a significant technical barrier for high-throughput and automated measurements. Herein,online ER-MS was conducted using LC-MS platform,and a pair of isomers,kaempferol vs luteolin,were employed as a case study to illustrate and assess the utility of online ER-MS for isomeric discrimination. High-resolution tandem mass spectrometry data of both flavonoids were acquired on LC-QE-Orbitrap-MS,and the fragmentation pathways responsible for the primary fragment ions were proposed. The primary signal in MS1 occurred at m/z 285( [M-H]-),and the primary signals of either compound generated by retro-Diels-Alder fragmentation were observed at m/z 151 and 133. The spectral information was subsequently transferred onto LC-Qtrap-MS platform to carry out online ER-MS. Two precursor-to-product ion transition candidates were constructed as m/z 285>151 and 285>133,and either afterward derived a set of pseudo-ion transitions( PITs) and so forth,exactly corresponding to a series of progressive collision energies( eg-5,-8,-11 e V,and so on). All PITs were typed into the monitoring list of multiple reaction monitoring program to generate the peak area datasets. Either dataset was normalized using the highest values in the set and imported into Graph Pad Prism software to plot the Gaus-sian-shaped curve that was termed as the break-down graph. The apex of the regressive curve was termed as optimal collision energy( OCE). The OCE values corresponding to m/z 285>151 were calculated as-29. 06 e V and-35. 71 e V for kaempferol and luteolin,respectively. In the case of m/z 285>133,the OCEs were yielded as-44. 15 e V for kaempferol and-49. 01 e V for luteolin. With re-ference to their chemical structures,the location of hydroxyl group was regarded to be responsible for the differences of either m/z 285>151 or 285>133 between the isomers,attributing to their different bond properties. Above all,online ER-MS offers an eligible tool for isomeric discrimination,and provides meaningful information for the accurate chemical composition characterization based on LC-MS,which is not limited to Chinese herbal medicines.

Online pressurized liquid extraction enables directly chemical analysis of herbal medicines: A mini review.

Extraction is responsible for transferring components from solid materials into solvent. Tedious extraction procedures are usually involved in liquid chromatography-based chemical analysis of herbal medicines (HMs), resulting in extensive consumptions of organic solvents, time, energy, and materials, as well as the significant chemical degradation risks for those labile compounds. Fortunately, an emerging online pressurized liquid extraction (OLE, also known as online liquid extraction) technique has been developed for the achievement of directly chemical analysis for solid matrices in recent years, and in a short period, this versatile technique has been widely applied for the chemical analysis of HMs. In the present mini-review, we aim to briefly summarize the principles, the instrumentation, along with the application progress of this robust and flexible extraction technique in the latest six years, and the emerging challenges and future prospects are discussed as well. Special attention is paid onto the hyphenation of the versatile OLE module with LC-MS instrument. The described information is expected to introduce a promising OLE approach and to provide the guidance for the achievement of directly chemical analysis of, but not limited to, HMs.