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A rapid method based on pressurized liquid extraction followed by high-performance liquid chromatography coupled with evaporative light scattering detection was firstly developed for the quantitative analysis of two bioactive triterpenoids (acankoreoside A and acankoreagenin) in the leaves of Schefflera octophylla and Schefflera actinophylla. The analysis was performed on an Agilent Zorbax SB-Aq column (4.6 × 50 mm, 3.5 μm) with gradient elution of 0.1% formic acid and acetonitrile. Calibration curves of two analytes showed good linearity ( R2 > 0.9990) within the tested ranges. This novel method is simple, rapid and accurate, and the results of quantification showed that contents of each investigated compound is significant high in natural S. octophylla (6.36-14.83%), which indicated that natural S. octophylla as potential medicinal resource. Furthermore, hierarchical clustering analysis based on the typical peaks of acankoreoside A and acankoreagenin from the 17 tested samples showed that natural and cultured Schefflera species were in different clusters, which could provide a means of discriminating between Schefflera species from different origins. Thus, acankoreoside A and acankoreagnin could be selected markers for quality control of S. octophylla and S. actinophylla. [ABSTRACT FROM AUTHOR]

Abstract: An approach for rapid optimization of dual-mode gradient high performance liquid chromatography (HPLC) by response surface methodology (RSM) was developed for fast simultaneous separation of hydrophilic and hydrophobic components in Radix et Rhizoma Salviae Miltiorrhizae (Danshen) and its preparations. The aim of this study was to achieve a high throughput RSM optimization using a short ultra-high performance liquid chromatographic (UHPLC) column to simultaneously optimize flow rate and solvent gradient, and then transfer the optimized method to conventional HPLC for routine analytical purposes. The optimization was designed with Box Behnken design (BBD) and the global Derringer''s desirability was used for describing the multicriteria response variables. Sixty-two designed experiments were performed by UHPLC with a short sub-2μm column (2.1mm×50mm, 1.7μm) and a total running time of only 5h. The predicted gradient profile was further transferred to a long UHPLC column (2.1mm×100mm, 1.7μm) and a conventional HPLC columns (2.1mm×100mm, 3.5μm and 4mm×100mm, 5μm, respectively). Compared to the published methods, the newly developed dual-mode gradient is faster and more efficient at simultaneously separating hydrophilic and hydrophobic components in Danshen and its preparations. [Copyright &y& Elsevier]

Abstract: In the present study, an ultra performance liquid chromatography coupled with photo-diode array detector and time-of-flight mass spectrometry (UPLC–PDA–TOFMS) based chemical profiling approach to rapidly evaluate chemical consistency between traditional and dispensing granule decoctions of traditional medicine combinatorial formulae was proposed and validated using San–Huang–Xie–Xin–Tang (SHXXT) as a model combinatorial formula. Two different kinds of decoctions, namely traditional decoction: water extract of mixed three constituent herbs of SHXXT, and dispensing granules decoction: mixed water extract of each individual herbs of SHXXT, were prepared. Batches of these two kinds of decoction samples were subjected to UPLC–PDA–TOFMS analysis, the datasets of t R–m/z pairs, ion intensities and sample codes were processed with supervised orthogonal partial least squared discriminant analysis (OPLS–DA) to holistically compare the difference between these two kinds of decoction samples. Once a clear classification trend was found in score plot, further statistics was performed to generate S-plot, in which the variables (t R–m/z pair) contributing most to the difference were clearly depicted as points at the two ends of “S”, and the components that correlate to these ions were regarded as the most changed components during decocting of combinatorial formula. The identities of the changed components can be identified by comparing the mass/UV spectra and retention times with those of reference compounds and/or tentatively assigned by matching empirical molecular formulae with those of the known compounds published in the literatures. Using the proposed approach, global chemical difference was found between traditional and dispensing granule decoctions, and berberine, palmatine, epiberberine, baicalin, wonogoside, 2-O-golloyl-1-O-cinnamoylglucose and emodin were identified as the most changed components during decocting SHXXT. It is suggested that this newly established approach could be used practically for the evaluation of chemical consistency between traditional and dispensing granule decoctions of traditional medicine combinatorial formulae. [Copyright &y& Elsevier]

Abstract: In traditional Chinese medicine, raw and processed herbs are used to treat different diseases. Suitable chemical markers are crucial for the discrimination between raw and processed herbs. In this study, a novel strategy using UHPLC–TOFMS coupled with multivariate statistical analysis to rapidly explore potential chemical markers was proposed and validated. Using Radix Rehmanniae as a model herb, batches of raw and processed samples were determined by UHPLC–TOFMS. The datasets of t R–m/z pair, ion intensity and sample code were subjected to principal component analysis (PCA) and orthogonal partial least squared discriminant analysis (OPLS-DA) to holistically compare the difference between raw and processed samples. Once a clear cluster was found, extended statistics was performed to generate S-plot, in which the variables (t R–m/z pair) contributing most to the difference were clearly indicated as points at the two ends of “S”, and the components that correlate to these ions should be the processing-induced transformed components. These transformed components could be regarded as the potential chemical markers that can be used to distinguish between raw and processed herbs. The identity of the potential markers can be identified by comparing the mass/UV spectra and retention time with that of reference compounds and/or tentatively assigned by matching empirical molecular formula with that of the known compounds published. Using this proposed strategy, leonuride or its isomer and 5-(α-d-glucopyranosyl-(1-6)-α-d-glucopyranosyloxymethyl)-2-furancarboxaldehyde were rapidly explored as the most characteristic markers of raw and processed Radix Rehmanniae, respectively. This newly proposed strategy can not only be used to explore chemical markers but also to investigate the chemical transforming mechanisms underlying traditional herb processing. [Copyright &y& Elsevier]

Abstract: Eleven major isoflavonoids and three major astragalosides in the xylem and bark of cultivated Radix Astragali (RA) from different cultivated regions of China were determined by high performance liquid chromatography. The results showed that the contents of astragalosides in the bark are up to 74-fold higher than in the xylem, and that thin roots contained more astragalosides than thick roots. Although the contents of isoflavonoids varied between samples, no significant difference was observed between the isoflavonoids content of xylem and bark, or between that of thin and thick roots. It was also found that the chemical profile of isoflavonoids in the xylem and bark are related to their cultivated regions. Constituents in either xylem or bark were divided into five groups according to their chemical structures: (1) Group 1 (G1), contained calycosin and related constituents; (2) Group 2 (G2), contained ononin and related constituents; (3) Group 3 (G3), contained (6aR,11aR)-3-hydroxy-9,10-dimethoxypterocarpan and related constituents; (4) Group 4 (G4), contained (3R)-7,2′-dihydroxy-3′,4′-dimethoxyisoflavan and related constituents; and (5) Group 5 (G5), contained astragalosides, compounds AG I, AG II, and AG IV. Based on the integrated contents of constituents in each group, the cultivated region of RA was successfully distinguished by principal components analysis (PCA). Chemical constituents in RA cultivated from different regions of China were compared and it was concluded that the quality of thin RA roots is better than thick RA roots. [Copyright &y& Elsevier]

Abstract: A rapid, but sensitive and selective method for simultaneous screening and quantification of toxic pyrrolizidine alkaloids (PAs) by ultra performance liquid-chromatography (UPLC) coupled with tandem mass spectrometry (MS/MS) on a tandem quadrupole mass spectrometer (TQ-MS) is described. This was accomplished by incorporating the precursor ion scan (PIS) acquisition and multiple reaction monitoring (MRM) acquisition in the same UPLC–MS/MS run. Notably, the developed PIS approach for detecting two pairs of characteristic product ions at m/z 120/138 or 168/150, allowed specific identification of toxic retronecine and otonecine types PAs. This PIS method is highly sensitive with over 10-fold sensitivity improvement upon previously published LC–MS method. Moreover, this new approach is suitable for high sample throughput and was applied to the screening and quantifying toxic PAs in 22 samples collected from seven Parasenecio species and four Senecio species. In addition, coupling the MRM with PIS approach generated quantitative results equivalent to those obtained by conventional MRM-only approach. This coupled MRM with PIS approach could provide both qualitative and quantitative results without the need of repetitive analyses. [ABSTRACT FROM AUTHOR]

Abstract: In a well-controlled experiment, outliers discriminated by robust principal component analysis (RPCA) represent contents in samples which are of particular quality distinguishable from the rest of the others, therefore chemical constituents in a natural product causing discrimination between outliers and the majority of samples could be considered as analytical markers for quality control. Based on this strategy, a novel approach for rapidly exploring characteristic analytical markers was proposed for the quality control of extract granules of Radix Salviae Miltiorrhizae (EGRSM). In this study, large sizes of samples were analyzed via high-throughput ultra-high performance liquid chromatography–ultraviolet–quadrupole time-of-flight mass spectrometry (UHPLC–UV–Q-Tof MS). RPCA was first performed on the three groups of samples: RSM (the raw material), the in-house prepared aqueous extract of Radix Salviae Miltiorrhizae (AERSM) and commercial product of EGRSM, to determine the variation of specific constituents between raw material and the final products as well as the effect of manufacturing process on the overall quality. Then RPCA was performed on the commercial products of EGRSM to explore the applicability of identified characteristic markers for the quality control of EGRSM. Candidate markers were extracted by RPCA, and their molecular formulae were determined by high resolution electrospray ionization-mass spectrometric (ESI-MS) analysis. The suitability of identified markers was then evaluated by determining the relationship between quantities of the identified markers with their antioxidant activities biologically, and further confirmed in a variety of samples. In conclusion, the combination of RPCA with UHPLC–UV–Q-Tof MS is a reliable means to identify chemical markers for evaluating quality of herbal medicines. [Copyright &y& Elsevier]

Abstract: Polycyclic polyprenylated acylphloroglucinols (PPAPs) are a group of natural products isolated from different Garcinia species with a wide range of important biological activities. In this study, an ultra performance liquid chromatography (UPLC) coupled to photodiode-array detection and quadrupole time-of-flight mass spectrometry (Q-TOF) method was developed to characterize 16 PPAPs in 10 Garcinia species. In source dissociation techniques based on cone voltage fragmentation were used to fragment the deprotonated molecules and multiple mass spectrometry (MS/MS) using ramping collision energy were used to further break down the resulting product ions. The resulting characteristic fragment ions were generated by cleavage of C1–C5 bond and C7–C8 bond through concerted pericyclic reaction, which is especially valuable for differentiating three types of PPAPs isomers. As such, two new PPAPs isomers present in minor amount in the extracts of Garcinia oblongifolia were tentatively characterized by comparing their tandem mass spectra to the known ones. In addition, an UPLC–Q-TOF-MS method was validated for the quantitative determination of PPAPs. The method exhibited limits of detection from 2.7 to 21.4ngmL−1 and intra-day and inter-day variations were less than 3.7% and the recovery was in the range of 89–107% with RSD less than 9.0%. This UPLC–Q-TOF-MS method has successfully been applied to quantify 16 PPAPs in 32 samples of 10 Garcinia species, which were found to be a rich source of PPAPs. [ABSTRACT FROM AUTHOR]

Abstract: A statistic approach using response surface methodology (RSM) for optimization of the ultra-high performance liquid chromatography (UHPLC) gradient and ionization response of electrospray ionization mass spectrometry (ESI-MS) to analyze the main alkaloids from the plant matrices of six Meconopsi species is presented. The optimization was performed with Box–Behnken designs (BBD) and the multicriteria response variables were described using global Derringer''s desirability. Four parameters of UHPLC and six major parameters of ESI-MS were investigated for their contribution to analytes separation and response, leading to a total of 27 and 54 experiments being performed for each instrument, respectively. Quantitative analysis of four main alkaloids in nine samples from six Meconopsis species was employed to evaluate the statistical significance of the parameters on UHPLC–QTOF/ESI-MS analytes response. The results indicated that the optimized UHPLC–QTOF-MS method is very sensitive with the limit of detections (LODs) ranging from 0.5 to 0.1ng/ml. The overall intra-day and the inter-day variations were less than 2.45%. The recovery of the method was in the range of 94.3–104.8% with RSD less than 4.0%. This approach has important implication in sensitivity enhancement of the ultra-trace determination of alkaloids from complex matrixes in the fields of natural products, metabolomics and pharmacokinetics. [Copyright &y& Elsevier]

Abstract: An on-line ultra-high-performance liquid chromatography (UHPLC) coupled with photodiode-array detection and quadrupole time-of-flight tandem mass spectrometry (QTOF-MS/MS) method has been optimized and established for the qualitative and quantitative analysis of the important diterpenoids in the methanol extracts of 12 Salvia species. Specific marker components were identified for the classification of the Salvia samples by principal component analysis. The accurate mass measurement within 3ppm error for all the protonated molecules and subsequent fragment ions offers higher quality structural information for interpretation of fragmentation pathways of various groups of diterpenoids. Thus, a total of 21 diterpenoids from different Salvia species were separated within 10min, and were unequivocally or tentatively identified via comparisons with authentic standards and literature. This UHPLC-QTOF-MS/MS method was validated to be sensitive, precise and accurate with the limit of detections at 3.0–16ng/ml, and the overall intra-day and the inter-day variations less than 3%. The recovery of the method was in the range of 96.2–101.8%, with relative standard deviation (RSD) less than 3.0%. The results demonstrated that the qualitative and quantitative differences in diterpenoids were not only useful for chemotaxonomy in some Salvia species but also for the standardization and differentiation of large numbers of similar samples. [Copyright &y& Elsevier]

Abstract: A screening system, composed of high-speed counter-current chromatography and high-pressure liquid chromatography/electrospray ionization quadrupole time-of-flight mass spectrometry, was established to find bioactive lead compound. This system succeeded in discovering apoptosis inducers from gamboge, the resin of Garcinia hanburyi. High-speed counter-current chromatography was used to provide well-separated fractions for bioassay and the resulted active fractions were rapidly identified using high-pressure liquid chromatography/electrospray ionization quadrupole time-of-flight mass spectrometry. The solvent system of n-hexane/ethyl acetate/methanol/water was optimized to the ratio of 7:3:7:3 (v/v/v/v) by a K value analysis. As a result, two active fractions were obtained. They showed apoptosis inducing effects as potent as that of taxol (500nM) at the concentration of 1μg/ml. Gambogenic acid (72.1%) and epimeric isogambogic acids (25.3%) were identified in one of the fractions. The other active fraction mainly contained two epimeric mixtures, gambogic acids (68.7%) and gambogoic acids (26.9%). Among them, gambogenic acid, without epimerization, has priority to be lead compound. [Copyright &y& Elsevier]

Abstract: A reliable and sensitive on-line high-performance liquid chromatography (HPLC) coupled with electrospray quadrupole time-of-flight tandem mass spectrometry (ESI-QTOF-MS/MS/MS) method has been optimized and established for the analysis of polyprenylated xanthones in the plant Garcinia xipshuanbannaensis. Collision induced MS/MS techniques were used to fragment the precursor molecular ions and MS/MS/MS techniques based on cone voltage fragmentation were used to further break down the resulting product ions sequentially. It was found that Retro–Diels–Alder rearrangement occurred from the xanthone skeleton in the MS/MS/MS process and produced characteristic fragment ions, which are useful for differentiating some positional isomers containing the prenyl unit on the A ring or B ring. Complementary fragmentation information, for instance the successive loss of prenyl residues, is also valuable for the identification of this class of xanthones. Under optimized HPLC–MS/MS/MS method, a total of 15 prenylated xanthones could be separated within 10min. This method also provided information about the molecular formula of a precursor molecule and its fragments, which could be used for dereplication of known or likely new prenylated xanthones in Garcinia plants before the purification and structural elucidation process. [Copyright &y& Elsevier]