Identification of Pulsatilla chinensis (Bge.) Regel and look-alike species by UHPLC-TOF-MS using multivariate statistical analysis

Pulsatillae Radix, the root of Pulsatilla chinensis (Bge.) Regel, is recorded in the Pharmacopoeia of the People's Republic of China and has been widely used for its pharmacological activities, such as anti-inflammatory, antioxidant, antibacterial, antitumor, and cardiovascular benefits. However, there are several look-alike species that can be marketed as Pulsatillae Radix. To distinguish P. chinensis (Bge.) Regel from its look-alikes, viz. Pulsatilla cernua (Thunb.) Bercht et Opiz., Pulsatilla dahurica (Fisch.) Spreng., Anemone tomeutosa (Maxim.) Pei., and Rhaponticum uniflorum (L.) DC, we used ultra high performance liquid chromatography with time-of-flight mass spectrometry combined with principal component analysis to compare their chemical compositions. Four ions, a (RT 8.98 min, m/z 1381.6671), b (RT 10.64 min, m/z 1219.6143), c (RT 11.52 min, m/z 1217.5978), and d (RT 13.6 min, m/z 749.4463), from P. chinensis (Bge.) Regel were identified as potential chemical markers to distinguish it from look-alike species using an unsupervised statistical model combined with orthogonal partial least-squares discriminant analysis. The results of this study provide an effective method for identifying and distinguishing P. chinensis (Bge.) Regel from similar plants.     

On-line HPLC combined with multivariate statistical process control for the monitoring of reactions

On-line high performance liquid chromatography is used to monitor a steady state reaction over 35.2 h, with 197 chromatograms recorded as the reaction progresses. For each chromatogram, peaks are detected, baseline corrected, aligned and integrated to provide a peak table consisting of the intensities of 19 peaks, two corresponding to the reactants, one to the product and one to the solvent, the remaining being impurities, by-products or intermediates. D-charts and Q-charts from multivariate statistical process control are applied to the data to determine which samples are out of control and also provide diagnostic insight into why these samples are problematic. The D-chart is best at looking at overall performance issues such as problems with mixing or difficulties with instrument operation, whereas the Q-charts are best at detecting impurities during the reaction.     

Dynamic changes of metabolite accumulation in Scrophulariae Radix based on liquid chromatography–tandem mass spectrometry combined with multivariate statistical analysis

Scrophulariae Radix is one of the most popular traditional Chinese medicines. The harvesting time of Scrophulariae Radix is closely related to the quality of products in this traditional Chinese medicine. The goal of the study is to analyze the dynamic changes of metabolite accumulation in Scrophulariae Radix. The difference of constituents in Scrophulariae Radix harvested at different times was analyzed by liquid chromatography with triple quadrupole‐time of flight tandem mass spectrometry coupled with principal component analysis and partial least‐square discriminant analysis. According to the accurate mass of molecular and product ions provided by triple quadrupole‐time of flight tandem mass spectrometry, a total of 30 differential constituents were identified. Furthermore, the contents of ten index differential constituents in Scrophulariae Radix were simultaneously determined by liquid chromatography coupled with triple quadrupole‐linear ion trap tandem mass spectrometry. Gray relational analysis was performed to evaluate the samples harvested at different times according to the contents of ten constituents. All of the results demonstrated that the quality of Scrophulariae Radix collected at traditional harvest time was better. This study will provide the basic information for revealing the dynamic change law of metabolite accumulation of Scrophulariae Radix and exploring its quality forming mechanism.     

High‐performance liquid chromatography–based fingerprint analysis with chemical pattern recognition for evaluation of Mahonia bealei (Fort.) Carr

A simple and efficient high‐performance liquid chromatography method combined with chemical pattern recognition was established for quality evaluation of Mahonia bealei (Fort.) Carr. A common pattern of 30 characteristic peaks was applied for similarity analysis, hierarchical cluster analysis, principal component analysis, and partial least squares discriminant analysis in the 37 batches of M. bealei (Fort.) Carr. to discriminate wild M. bealei (Fort.) Carr., cultivated M. bealei (Fort.) Carr., and its substitutes. The results showed that partial least squares discriminant analysis was the most effective method for discrimination. Eight characteristics peaks with higher variable importance in projection values were selected for pattern recognition model. A permutation test and 26 batches of testing set samples were performed to validate the model that was successfully established. All of the training and testing set samples were correctly classified into three clusters (wild M. bealei (Fort.) Carr., cultivated M. bealei (Fort.) Carr., and its substitutes) based on the selected chemical markers. Moreover, 26 batches of unknown samples were used to predict the accuracy of the established model with a discrimination accuracy of 100%. The obtained results indicated that the method showed great potential application for accurate evaluation and prediction of the quality of M. bealei (Fort.) Carr.     

Differentiation of betamethasone and dexamethasone using liquid chromatography/positive electrospray tandem mass spectrometry and multivariate statistical analysis

Betamethasone and dexamethasone are two corticosteroids differing in the stereoisomery of their C-16 methyl group. These two compounds are imperfectly separated by reversed-phase liquid chromatography and their mass spectra are very similar, leading to a difficult unambiguous identification according to European criteria. A method is proposed for differentiating betamethasone and dexamethasone using liquid chromatography/tandem mass spectrometry and multivariate statistical analysis. Multiple analysis of variance was used for the justification and the selection of diagnostic ions. Principal component analysis permitted the suitability of the approach to be tested on a large number of samples. Discriminant factorial analysis was finally performed to build a decisional model based on the six most significant ions. This novel utilization of mass spectrometric data appeared efficient for the unambiguous identification of the target analytes in urine samples.     

三波长融合指纹图谱结合6组分定量和主成分分析评价银翘解毒片的质量

建立了三波长融合高效液相色谱指纹图谱,并结合6组分定量和主成分分析(PCA)评价25批银翘解毒片的质量一致性。采用反相高效液相色谱法(RP-HPLC)分别于230、279、327 nm下检测。运用多波长融合指纹图谱技术建立银翘解毒片三波长融合指纹图谱,采用系统指纹定量法对其进行定性和整体定量评价。结果鉴别出25批银翘解毒片样品完全合格且区分良好。同时测定6组分含量,与指纹图谱结合,从整体和局部角度评价银翘解毒片质量。此外,运用PCA法对融合指纹图谱进行分析,通过主成分得分图可以明显区分来自两个厂家的25批银翘解毒片样品。方法综合性较强且有效,为科学评价与有效控制银翘解毒片的质量提供了可靠的参考。     

Approach based on high‐performance liquid chromatography fingerprint coupled with multivariate statistical analysis for the quality evaluation of Gastrodia Rhizoma

Gastrodia Rhizoma is a Traditional Chinese Medicine applied in the treatment of stroke, numbness of limb, headache and dizziness. However, its clinical effect is threatened by sulfur‐fumigation used in the process of storage. This article employs content determination coupled with high‐performance liquid chromatography fingerprint to investigate the effect of sulfur‐fumigation on Gastrodia Rhizoma so as to evaluate the quality of Gastrodia Rhizoma. The result was that most active ingredient in Gastrodia Rhizoma decreased after sulfur‐fumigation and the fingerprints analyzed by mathematical statistics between sulfur‐fumigated Gastrodia Rhizoma and unfumigated Gastrodia Rhizoma have substantial differences, which reveals that sulfur‐fumigation has a significant influence on the quality of Gastrodia Rhizoma. The conclusion of hierarchical clustering analysis, principal component analysis and partial least squares could validate each other, which implies that the method of mathematical statistics applied for assessing the quality of Gastrodia Rhizoma is effective and stable. The method not only affords a viable strategy for distinguishing Gastrodia Rhizoma whether sulfur‐fumigated or not and assessment of the quality of Gastrodia Rhizoma, but also provides a reference for other herbal medicine that suffers from sulfur‐fumigation.     

Monitoring the quality consistency of Weibizhi tablets by micellar electrokinetic chromatography fingerprints combined with multivariate statistical analyses,the simple quantified ratio fingerprint method,and the fingerprint–efficacy relationship

Micellar electrokinetic chromatography fingerprinting combined with quantification was successfully developed and applied to monitor the quality consistency of Weibizhi tablets, which is a classical compound preparation used to treat gastric ulcers. A background electrolyte composed of 57 mmol/L sodium borate, 21 mmol/L sodium dodecylsulfate and 100 mmol/L sodium hydroxide was used to separate compounds. To optimize capillary electrophoresis conditions, multivariate statistical analyses were applied. First, the most important factors influencing sample electrophoretic behavior were identified as background electrolyte concentrations. Then, a Box–Benhnken design response surface strategy using resolution index RF as an integrated response was set up to correlate factors with response. RF reflects the effective signal amount, resolution, and signal homogenization in an electropherogram, thus, it was regarded as an excellent indicator. In fingerprint assessments, simple quantified ratio fingerprint method was established for comprehensive quality discrimination of traditional Chinese medicines/herbal medicines from qualitative and quantitative perspectives, by which the quality of 27 samples from the same manufacturer were well differentiated. In addition, the fingerprint–efficacy relationship between fingerprints and antioxidant activities was established using partial least squares regression, which provided important medicinal efficacy information for quality control. The present study offered an efficient means for monitoring Weibizhi tablet quality consistency.     

Chemometric analysis of metabolism disorders in blood plasma of S180 and H22 tumor‐bearing mice by high performance liquid chromatography‐diode array detection

The aim of this paper is to characterize metabolism disorders in Kunming mice induced by S180 and H22 tumor cells. Metabolic fingerprint based on high performance liquid chromatography‐diode array detector (HPLC‐DAD) was developed to map the disturbed metabolic responses. In vivo testing of the antitumor activity of paclitaxel (Taxol) was carried out by inhibiting the growth of S180 and H22 tumor cells. Based on 27 common peaks, principal component analysis (PCA) and partial least squares‐discriminant analysis (PLS‐DA) were used to distinguish the abnormal from control and to find significant endogenous compounds (SECs) which have significant contributions to classification. The tumor growth inhibition ratios (TIRs) of Taxol groups were used to validate the predictive accuracies of the PLS‐DA models. The predictive accuracies of PLS‐DA models for S180 and H22 tumor model groups were 97.6 and 100%, respectively. Nine (S180) and seven (H22) SECs were discovered, including uric acid and cytidine. In addition, the correlations between relative tumor weights (RTWs) and chromatographic data for the SECs were significant (p < 0.05). Investigations on the stability and precision of the established metabolic fingerprints demonstrate that the experiment is well controlled and reliable. This work shows that the platform of HPLC‐DAD coupled with chemometric methods provides a promising method for the study of metabolism disorders induced by tumor cells. Copyright © 2011 John Wiley & Sons, Ltd.     

Quality evaluation of Shenmaidihuang Pills based on the chromatographic fingerprints and simultaneous determination of seven bioactive constituents

In this study, we aimed to establish a comprehensive and practical quality evaluation system for Shenmaidihuang pills. A simple and reliable high‐performance liquid chromatography coupled with photodiode array detection method was developed both for fingerprint analysis and quantitative determination. In fingerprint analysis, relative retention time and relative peak area were used to identify the common peaks in 18 samples for investigation. Twenty one peaks were selected as the common peaks to evaluate the similarities of 18 Shenmaidihuang pills samples with different manufacture dates. Furthermore, similarity analysis was applied to evaluate the similarity of samples. Hierarchical cluster analysis and principal component analysis were also performed to evaluate the variation of Shenmaidihuang pills. In quantitative analysis, linear regressions, injection precisions, recovery, repeatability and sample stability were all tested and good results were obtained to simultaneously determine the seven identified compounds, namely, 5‐hydroxymethylfurfural, morroniside, loganin, paeonol, paeoniflorin, psoralen, isopsoralen in Shenmaidihuang pills. The contents of some analytes in different batches of samples indicated significant difference, especially for 5‐hydroxymethylfurfural. So, it was concluded that the chromatographic fingerprint method obtained by high‐performance liquid chromatography coupled with photodiode array detection associated with multiple compounds determination is a powerful and meaningful tool to comprehensively conduct the quality control of Shenmaidihuang pills.     

Classification of Aurantii Fructus samples by multivariate analysis

Twenty commercial samples of Aurantii Fructus Immaturus (Poncitrus trifoliata) and 30 of Aurantii Fructus Maturus (Citrus aurantium and C. wilsonii) were collected from the Taiwan and China herbal markets. The contents of 12 constituents in these samples were determined by HPLC and were used to assess the potential relationships with their plant origins. Multivariate analysis including principal component analysis (PCA), cluster analysis (CA), and linear discriminant analysis (LDA) were used as classification procedures. Natural groupings of the samples divided into three sets successfully, 20 P. trifoliata, 15 C. aurantium, and 15 C. wilsonii, were observed by using PCA and CA. The application of LDA gave correct assignation percentages of 100.0% for all three groups.     

Micellar electrokinetic capillary chromatography fingerprints combined with multivariate statistical analyses to evaluate the quality consistency and predict the fingerprint–efficacy relationship of Salviae miltiorrhizae Radix et Rhizoma (Danshen)

Micellar electrokinetic capillary chromatography fingerprinting combined with quantification was successfully established and applied to evaluate the quality consistency of Danshen, which is a medicinal herb used to treat various diseases, especially coronary cerebrovascular diseases. A background electrolyte composed of 20 mmol/L sodium tetraborate, 90 mmol/L orthoboric acid, 25 mmol/L sodium phosphate monobasic dehydrate, and 65 mmol/L sodium dodecyl sulfate was used to separate compounds. To optimize micellar electrokinetic capillary chromatography conditions, a response surface strategy was set up for orthogonal experimental design. In fingerprint assessments, a systematic quantified fingerprint method was established for integrated quality assessment of Danshen samples from qualitative and quantitative perspectives, by which the quality of 30 samples was well differentiated. The principal component analysis coupled with quantitative determination of two components was applied to explain that the quality consistency of the medicinal herb was relatively good within one harvest season, but poor among harvest seasons for the Danshen samples. In addition, the fingerprint–efficacy relationship between the chemical fingerprints and antioxidant activities was investigated utilizing orthogonal projection to latent structures, which provided important medicinal efficacy information for quality control. This work offered an efficient, holistic, and powerful approach to evaluate the quality consistency of Danshen samples.     

银莱汤中主要成分的UPLC多波长宽动态测定及质量评价研究

采用超高效液相色谱(UPLC)定量测定银莱汤中10种有效成分的含量并用于其质量评价.采用Wa-ters ACQUITY UPLC HSS T3色谱柱(2.1 mm × 100 mm,1.8 μm),以0.1％甲酸水溶液-0.1％甲酸乙腈为流动相梯度洗脱,3波长切换(0～10 min,320 nm;10～16 min,3...     

Quality and antitumour activity evaluation of extract of Hypericum ascyron

Similarity assessment of complex chromatographic profiles is a potential tool for the identification and quality control of herbal medicinal products to guarantee the expected biological activity. In this paper, a high‐performance liquid chromatography method was established for controlling the quality of extract of Hypericum ascyron for the first time. With this method, the correlation coefficients of similarity of 10 batches extract of H. ascyron were >0.97. The extract of H. ascyron displayed steadily inhibitorty activities on the growth of human cervical cancer Hela cell lines. Therefore, the present study successfully set up a sensitive efficient method which might confirm stable biological activity of the extract of H. ascyron. Copyright © 2014 John Wiley & Sons, Ltd.     

Quality assessment of crude and processed Arecae semen based on colorimeter and HPLC combined with chemometrics methods

Raw Arecae Semen, the seed of Areca catechu L., as well as Arecae Semen Tostum and Arecae semen carbonisata are traditionally processed by stir‐baking for subsequent use in a variety of clinical applications. These three Arecae semen types, important Chinese herbal drugs, have been used in China and other Asian countries for thousands of years. In this study, the sensory technologies of a colorimeter and sensitive validated high‐performance liquid chromatography with diode array detection were employed to discriminate raw Arecae semen and its processed drugs. The color parameters of the samples were determined by a colorimeter instrument CR‐410. Moreover, the fingerprints of the four alkaloids of arecaidine, guvacine, arecoline and guvacoline were surveyed by high‐performance liquid chromatography. Subsequently, Student's t test, the analysis of variance, fingerprint similarity analysis, hierarchical cluster analysis, principal component analysis, factor analysis and Pearson's correlation test were performed for final data analysis. The results obtained demonstrated a significant color change characteristic for components in raw Arecae semen and its processed drugs. Crude and processed Arecae semen could be determined based on colorimetry and high‐performance liquid chromatography with a diode array detector coupled with chemometrics methods for a comprehensive quality evaluation.     

Study on phenolic acids of Lonicerae japonicae Flos based on ultrahigh performance liquid chromatography-tandem mass spectrometry combined with multivariate statistical analysis

Lonicerae japonicae Flos, a traditional Chinese medicine, has the function of evacuating heat and detoxifying. To promote the optimization of Lonicerae japonicae Flos germplasms and improve the quality of medicinal materials, 55 batches of five Lonicerae japonicae Flos germplasms with the same origin were collected during different periods, a UHPLC-TOF-MS method was established, and 22 kinds of phenolic acids were found and qualitatively analysed. Seventeen phenolic acids were selected for quantitative analysis by UHPLC-QqQ-MS/MS, and the quantitative results were analysed by principal component analysis, orthogonal partial least squares-discriminant analysis, and partial least squares discriminant analysis. The contents of phenolic acids in periods S1–S6 were found to be significantly different. There were also significant differences in the accumulation of phenolic acids in Lonicerae japonicae Flos during different growth periods. Ferulic acid, 5-O-caffeoylquinic acid, and caffeic acid were determined to be important components to distinguish the different growth periods of Lonicerae japonicae Flos. There were significant differences in the phenolic acid content of different germplasms of Lonicerae japonicae Flos, and the total amount of 17 phenolic acids and total acids (chlorogenic acid, 3,5-di-O-caffeoylquinic acid, and 4,5-di-O-caffeoylquinic acid) in “Hua Jin No. 6” was highest, so the quality of “Hua Jin No. 6” was better than that of the four other germplasms. In addition, chlorogenic acid methyl ester and caffeic acid were the smallest markers in combination to distinguish the five germplasms of Lonicerae japonicae Flos.     

Strategies for determining the bioactive ingredients of honey‐processed Astragalus by serum pharmacochemistry integrated with multivariate statistical analysis

Honey‐processed Astragalus is a widely used traditional Chinese medicine that has a better effect on reinforcing “Qi” (vital energy) than the raw one. A comparative study of metabolites analysis between them in rat serum for finding the bioactive ingredients was carried out using serum pharmacochemistry and multivariate statistical analysis. The blood collection methods and time were optimized first. Then the prototypes and metabolites in serum samples after oral administration were investigated by ultra‐high‐performance liquid chromatography coupled with electrospray ionization quadrupole time‐of‐flight mass spectrometry integrated with principal component analysis and orthogonal partial least squares discriminant analysis. The contents of metabolites were also analyzed to evaluate the metabolic profile differences. As a result, nine prototypes and 36 metabolites were identified. Only two prototypes and 15 metabolites were different between raw and honey‐processed Astragalus. Their biotransformation reactions contained the process of oxidation, demethylation, and hydrolysis in phase I and glucuronide conjugation or sulfate conjugation in phase II. Most of the detected metabolites were transformed from isoflavones and isoflavanes. Our results expand the knowledge about the influence of honey‐processing on Astragalus and suggest the different curative effects between raw and honey‐processed Astragalus might due to their therapeutic material discrepancy.     

Quantitative fingerprinting based on the limited‐ratio quantified fingerprint method for an overall quality consistency assessment and antioxidant activity determination of Lianqiao Baidu pills using HPLC with a diode array detector combined with chemometric methods

Lianqiao Baidu pills are widely used herbal medicinal preparation that were analyzed to develop a quality consistency technique. The characteristic fingerprints of 28 batches of Lianqiao Baidu pill samples were established at five wavelengths and simultaneously assessed by using a limited‐ratio quantified fingerprint method using 15 marker compounds. The principal component analysis and fingerprinting results were compared, and the qualitative classification of the samples by principal component analysis agreed with their quantitative evaluation by the limited‐ratio quantified fingerprint method. Furthermore, the antioxidant activities of the samples were surveyed and determined using a 2,2‐diphenyl‐1‐picrylhydrazyl radical‐scavenging approach. A relationship between the common peaks in the fingerprints and the antioxidant activities was established using a partial least squares model. The relationship can be used both to determine the antioxidant activities of the Lianqiao Baidu pill preparations in vitro and as a reference for the selection of active constituents for sample quality classification. The classification results for the samples based on principal component analysis agreed with the quantitative evaluation by the limited‐ratio quantified fingerprint method, which demonstrated that the method can be applied to the holistic quality control of traditional Chinese medicine and herbal preparations.     

Ultrasound-assisted emulsification microextraction based on solidification of floating organic droplet combined with HPLC-UV for the analysis of antidepressant drugs in biological samples

Ultrasound-assisted emulsification microextraction based on the solidification of floating organic droplet combined with high-performance liquid chromatography-ultra violet (HPLC-UV) detection was applied for the extraction and determination of fluoxetine, citalopram, and venlafaxine as antidepressants drugs in biological samples. In total, 30 μL of undecanol was injected slowly into a glass-centrifuge tube containing 5 mL alkaline sample solution that was located inside the ultrasonic water bath. The formed emulsion was centrifuged and the fine droplets of solvent were floated at the top of the test tube. The test tube was then cooled in an ice bath and the solidified solvent transferred into a conical vial; it melted quickly at room temperature. Then the analysis of the extracts was carried out by high-performance liquid chromatography. Under optimal conditions, the preconcentration factors were between 174 and 316. Detection limits (LODs) of 3 μg/L were obtained and the calibration graphs were linear within the range of 10-1000 μg/L. Finally, the feasibility of the proposed method was successfully confirmed by extraction and determination of the antidepressant drugs in human urine and plasma samples in the range of microgram per liter and suitable results were obtained.     

Fingerprint analysis and multi‐ingredient quantitative analysis for quality evaluation of Xiaoyanlidan tablets by ultra high performance liquid chromatography with diode array detection

A rapid and sensitive ultra high performance liquid chromatography method with diode array detection was developed for the fingerprint analysis and simultaneous determination of seven active compounds in Xiaoyanlidan (XYLD) tablets. The chromatographic separations were obtained on an Agilent Eclipse plus C₁₈ column (50 × 2.1 mm id, 1.8 μm) using gradient elution with water/formic acid (1%) and acetonitrile at a flow rate of 0.4 mL/min. Within 63 min, 36 peaks could be selected as the common peaks for fingerprint analysis to evaluate the similarities among several samples of XYLD tablets collected from different manufacturers. In quantitative analysis, seven compounds showed good regression (R > 0.9990) within test ranges and the recovery of the method was within the range of 95.9–104.3%. The method was successfully applied to the simultaneous determination of seven compounds in six batches of XYLD tablets. These results demonstrate that the combination of chromatographic fingerprint analysis and simultaneous multi‐ingredient quantification using the ultra high performance liquid chromatography method with diode array detection offers a rapid, efficient, and reliable approach for quality evaluation of XYLD tablets.