Purification of lignans from Fructus Arctii using off‐line two‐dimensional supercritical fluid chromatography/reversed‐phase liquid chromatography

As a common traditional Chinese medicine, Fructus Arctii has important clinical medical values. Its main components are lignans, which are difficult to separate and analyze because of the complex composition, similar chemical structures, and close properties. In this study, an off‐line two‐dimensional supercritical fluid chromatography/reversed‐phase liquid chromatography method, as well as an effective sample pretreatment method based on hydrophilic interaction chromatography material, was developed to enrich the minor lignan fractions and obtain high‐purity compounds. In total, 12 high‐purity compounds were isolated from Fructus Arctii . Their structures were identified by using high‐resolution mass spectrometry and nuclear magnetic resonance spectroscopy, which showed that all were lignans and that most of them were isomers. The results demonstrated the effective off‐line two‐dimensional supercritical fluid chromatography/reversed‐phase liquid chromatography method for the purification of lignans from Fructus Arctii . The separation protocol established here will be beneficial for the separation of complex samples from other kinds of natural products.     

Quality evaluation of raw and processed Crataegi Fructus by color measurement and fingerprint analysis

Crataegi Fructus and its processed products have been used as a traditional medicine for a long time, and numerous active components are responsible for their curative effects. However, a comprehensive and fast method for the quality control of its processed products is still lacking. In this study, two analytical methods based on color measurements and fingerprint analysis are established. In the color measurements, the color values of the peel and flesh of Crataegi Fructus were evaluated spectrophotometrically. Based on the results, a color reference range was established using percentiles, and the standard color difference value was established using the median color values. Then, the color values of Crataegi Fructus and its processed products were analyzed using Bayes linear discriminant analysis and mathematical functions were built in order to predict the degree of processing. Moreover, high‐performance liquid chromatography fingerprint analysis was performed on a Hibar C₁₈ column, and a high‐performance liquid chromatography fingerprint pattern was obtained, from which nine peaks were identified. Chemometric methods were successfully applied to differentiate raw and processed Crataegi Fructus.     

Differentiation of various kinds of Fructus schisandrae by surface desorption atmospheric pressure chemical ionization mass spectrometry combined with principal component analysis

Various kinds of Fructus schisandrae were studied by surface desorption atmospheric pressure chemical ionization mass spectrometry (DAPCI-MS) without any sample pretreatment. The volatile components in F. schisandrae were detected in the ambient environment and the analytical time for each sample was only 30 s. F. schisandrae are produced mainly in 5 different geographical regions (Elunchun, Mudanjiang, Tonghua, Tieling and Shangluo), and they could be successfully differentiated according to their chemical markers by Principal Component Analysis (PCA). A total of 8 components which gave more contribution for PCA analysis were unambiguously identified by comparison of the MS² data of chemical markers to the data of reference compounds as reported in the literature. Similarly, wild grown and cultivatable species of F. schisandrae were well separated by the above-mentioned method. In addition, raw and processed cultivatable F. schisandrae (steamed by water, alcohol, vinegar, or honey, and fried by honey) were found to be clustered at different location, respectively. Furthermore, the clustered degree of differently processed products was correlated with their clinical effects. Our results demonstrated that DAPCI-MS in combination with PCA was a feasible technique for high-throughput differentiation of various kinds of F. schisandrae. It is also possible that DAPCI-MS could become a powerful technology in the studies of traditional Chinese medicine studies and in situ analysis of Chinese herbs.     

Quality assessment of raw and baked Aucklandia lappa Decne. by color measurement and fingerprint analysis

Aucklandia lappa Decne. has been used as a traditional Chinese herb for thousands of years in treating various kinds of disorders. According to the Chinese Pharmacopoeia, there are two kinds of processed products, raw and baked Aucklandia lappa Decne., which have different therapeutic effect in clinical application. In this study, based on color measurement and fingerprint analysis, the method to assess the quality of these two processed products was established. In color measurement, the reference ranges of color parameters (L^*, a^*, and b^*), standard color difference values, and mathematical prediction functions of these two processed products were obtain after the color was measured by a spectrophotometer. Meanwhile, high‐performance liquid chromatography fingerprints of these two processed products were established, where there were 12 peaks recognized as the common peaks in both processed products, in which two peaks were identified as costunolide and dehydrocostus lactone, and these two processed products were classified with chemometrics analysis subsequently. Furthermore, the correlation between color parameters and sample compositions was explored and the contents of costunolide and dehydrocostus lactone were determined simultaneously by high‐performance liquid chromatography. Consequently, an integral method including color measurement, high‐performance liquid chromatography fingerprint with chemometrics analysis, and quantitative determination was established.     

A multi-evaluating strategy for raw and processed Veratrum nigrum L.: Fingerprinting combined with quantitative analysis based on multivariate chemometric methods

Veratrum nigrum L. (VN) is a well-known herbal medicine and rich in chemical components with multiple pharmacological activities including antihypertensive, anticancer, and antifungal effects. In the current experiment, the quality of VN from different habitats was evaluated based on combinative method of fingerprint, multi-component quantification and chemical pattern recognition. Fifteen batches of VN were collected, and intrinsic chemical composition were identified using ultra-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry, which is a method for analyzing the similarity between samples, coupled with fingerprint of traditional Chinese medicine. The fingerprint similarity model show that 22 common peaks were selected covering 15 batches of and the similarity > 0.963. The total of 22 joint components were tentatively identified by comparison with standard substances or literature. A ultra-high performance liquid chromatography coupled with triple quadrupole mass spectrometry method for simultaneous determination of 8 compounds was established to evaluate the contents of raw and processed Veratrum nigrum L. Multivariate analysis was then applied to compare different batches of herbs based on ultra-high performance liquid chromatography coupled with triple quadrupole mass spectrometry data. All raw and processed samples were classified by partial least squares discriminant analysis based on the 8 analyzed compounds. The findings suggested that veratramine and polydatin with a variable importance for the project (VIP) > 1 were identified as significant constituents, the presence of which can be used to differentiate between raw and processed Veratrum nigrum L. samples. These results indicate that processing methods show important effects on the composition of Veratrum nigrum L..     

High‐performance liquid chromatography with photodiode array detection and chemometrics method for the analysis of multiple components in the traditional Chinese medicine Shuanghuanglian oral liquid

Shuanghuanlian oral liquid, a traditional Chinese medicine preparation, is a mixture of three herbs (Flos Lonicerae, Radix Scutellariae and Fructus Forsythiae). In this study, the quantitative analysis of three main active compounds, chlorogenic acid, forsythin and baicalin in samples from different manufacturers was performed rapidly by high‐performance liquid chromatography coupled with photodiode array detection followed by Contour Projection coupled to stepwise regression treatment of the obtained three‐dimensional spectra in which the partial overlap between adjacent target components existed. The method was validated for linearity (R>0.9940), precision (RSD<1.25%), recovery (92.20–102.50%), limit of detection (0.01–0.02 μg/mL) and limit of quantification (0.03–0.07 μg/mL). The results indicated that the combination of the three‐dimensional spectra of traditional Chinese medicine and Contour Projection‐stepwise regression offered an accurate, simple, low‐cost and eco‐friendly way for the rapid quantitative analysis of Shuanghuanlian oral liquid samples.     

A comparative analysis of raw and processed Radix Paeoniae Alba samples using HPLC,chemometrics, and antioxidant activity

Radix Paeoniae Alba (RPA) and its processed products are commonly used in traditional Chinese medicine, but the chaos phenomenon among processed products often occurs. In this study, we used multiple chemometric methods to analyze raw and six different processed products of RPA based on HPLC fingerprinting. Heat map analysis was used to assess the changes in chemical composition. Principal component analysis was used for classification, and the samples were divided into four classes: class 1 (raw, wine-processed, and vinegar-processed products), class 2 (bran-processed and soil-processed products), class 3 (stir-fried products), and class 4 (coke products). Further, the orthogonal partial least squares discriminant analysis model was used to obtain chemical markers among different classes. The antioxidant property of RPA is an important factor responsible for its pharmacological effects, and so the antioxidant activity of RPA was also investigated. We measured 2,2-diphenyl-1-picrylhydrazyl radical (DPPH) and hydroxyl radical scavenging ability, and ferric reducing antioxidant power. The total antioxidant activity follows the order: coke > stir-fried > soil-processed > bran-processed > wine-processed > raw > vinegar-processed products. These results suggest that different processing methods affect the chemical composition and antioxidant power of RPA, and thus, different products of RPA should not be mixed.     

Qualitative and quantitative analysis of Alpiniae Oxyphyllae Fructus by high-performance liquid chromatography coupled to Fourier transform-ion cyclotron resonance mass spectrometry

Alpiniae Oxyphyllae Fructus, as a homology of medicine and food, has been widely used in China for thousands of years. However, the existing qualitative and quantitative methods are difficult to evaluate the quality of Alpiniae Oxyphyllae Fructus samples from multiple sources. In this paper, an high-performance liquid chromatography fingerprint was established for assessing the quality of Alpiniae Oxyphyllae Fructus from different areas. Then, high-performance liquid chromatography was coupled to Fourier transform-ion cyclotron resonance mass spectrometry for characterization of the chemical compositions in Alpiniae Oxyphyllae Fructus. In fingerprint analysis, 54 common peaks were confirmed and six chromatographic peaks of them were identified. The similarity of 14 samples from different areas was between 0.990 and 1.000. Moreover, a total of 30 chemical components were characterized by high-performance liquid chromatography coupled to Fourier transform-ion cyclotron resonance mass spectrometry method, six compounds of which were decisively identified. Finally, the content of nootkatone was determined by high-performance liquid chromatography. In conclusion, the methods used in this study are efficient for qualitative and quantitative analysis of Alpiniae Oxyphyllae Fructus. Also, these methods can be used to control the quality of other traditional Chinese medicines.     

Comparison of the active components of Aster tataricus from different regions and related processed products by ultra‐high performance liquid chromatography with tandem mass spectrometry

We investigated crude Aster tataricus, vinegar‐processed Aster tataricus, honey‐processed Aster tataricus, and steamed Aster tataricus as a case study and developed a comprehensive strategy integrating quantitative analysis and chemical pattern recognition methods for the evaluation and differentiation of Aster tataricus from different regions, as well as related processed products. In the study, 15 batches of raw Aster tataricus collected from seven provinces were analyzed. A sensitive and rapid ultra‐high performance liquid chromatography with tandem mass spectrometry method for simultaneous determination of 15 compounds was established to evaluate the quality of raw and processed Aster tataricus. Furthermore, multivariate statistical techniques were applied to compare the differences among Aster tataricus samples. As a result, the herbs collected from seven provinces were divided into two categories, and chlorogenic acid was the most important component distinguishing between the regions. Moreover, all of the raw and processed samples were classified by partial least squares discriminant analysis based on the 15 analyzed compounds. Results showed that raw Aster tataricus, vinegar‐processed Aster tataricus, honey‐processed Aster tataricus, and steamed Aster tataricus were clustered in four different areas. Shionone, chlorogenic acid and kaempferol were the significant constituents differentiating the raw and differently processed Aster tataricus samples.     

Identifying the chemical markers in raw and wine-processed Scutellaria baicalensis by ultra-performance liquid chromatography/quadrupole time-of-flight mass spectrometry coupled with multiple statistical strategies

Herb processing is a typical pharmaceutical preparation process for traditional Chinese medicine. After processing, its clinical applications and pharmacological effects vary greatly, which is most commonly attributed to the changing chemical properties between raw herb and processed products. In this work, a total of 53 chemical compounds were detected, among which 17 compounds were identified as discriminatory chemicals between raw and wine-processed Scutellaria baicalensis, and 10 components were identified as chemical markers with a cumulative content contribution of 88.75%. In addition, this work revealed that the best wine-processed time was 18 min by investigating the changes of chemical markers in S. baicalensis during processing. This work demonstrated that ultra-performance liquid chromatography/quadrupole time-of-flight mass spectrometry coupled with multiple statistical strategies is an effective approach for screening and identifying discriminatory chemical markers in complex traditional Chinese medicine.     

Study on the quality difference of Cyperus rotundus before and after vinegar processing based on ultra-high-performance liquid chromatography-quadrupole-time of flight-mass spectrometry and molecular network combined with color parameters

Cyperus rotundus is the dry rhizome of the Cyperaceae plant Cyperus. Although there are two types of processed products in clinics, their quality differences are not clear, and the identification methods are more complex. In this study, the chemical composition of different processed products of Cyperus rotundus was characterized using ultra-high-performance liquid chromatography-quadrupole-time of flight-mass spectrometry and molecular network analysis, to identify the potential chemical markers and to establish a quick and simple color-based discrimination method. Among the 65 compounds analyzed, 12 showed significant differences. Observing the color, the surface brightness (L*) of Cyperus rotundus decreased after vinegar processing, while red (a*) and yellow (b*) values increased. These color values correlated significantly with chemical compositions. Finally, a color discriminant function was established and verified for raw Cyperus rotundus and vinegar-processing Cyperus rotundus. Based on this study, Cyperus rotundus' quality can be effectively controlled and provides a method for the comprehensive characterization of chemical components and chemical markers of other traditional Chinese medicine and processed products, as well as new ideas and methods in identification and quality evaluation.     

Studies on the Components of Crude and Processed Fructus Corni by ESI-MSn

The components of crude and processed Fructus Corni were investigated by means of electrospray ionization-tandem mass spectrometry(ESI-MSn) technique in the negative ion mode. Compared with those of crude Fructus Corni, the chemical components of the processed Fructus Corni were changed both in quality and in quantity.From the ESI-MS spectra of the crude and processed Fructus Corni, six peaks were selected to establish the characteristic ESI-MS peaks. Several factors in the processing procedure were examined. The experimental results demonstrate that the chemical reactions that occurred in the processing procedure can be used for the elucidation of the processed mechanism of Fructus Corni, which is regularly affected by the processing conditions. The present article provides both the chemistry evidence for the understanding of the processing procedure of Fructus Corni and the specific methodology for the research of the processing procedure and quality identification of traditional Chinese medicine.     

Static headspace‐multicapillary column with gas chromatography coupled to ion mobility spectrometry as a simple approach for the discrimination of crude and processed traditional Chinese medicines

The processing procedure can alter the nature and chemical transformation of traditional Chinese medicine to accommodate different clinical dispensing and preparation requirements. In this study, static headspace‐multicapillary column with gas chromatography coupled to ion mobility spectrometry was developed for the rapid and sensitive discrimination of crude and processed traditional Chinese medicine. Using Radix Paeoniae Alba as a traditional Chinese medicine model, the combined power of this approach was illustrated by classifying the crude and processed Radix Paeoniae Alba samples into two main categories. The contents of the main components in Radix Paeoniae Alba varied significantly. The established method could promote the use of ion mobility spectrometry in intrinsic quality control and differentiation of herbal medicines from other processed products or preparations.     

Capillary electrophoresis fingerprinting coupled with chemometrics to evaluate the quality consistency and predict the antioxidant activity of Sanhuang tablet as part of its quality control

A capillary electrophoresis fingerprint was constructed for Sanhuang tablet, a Chinese traditional patent medicine, that was commonly used in clinical practice, where the isosceles trapezoid method was first applied for the optimization of background electrolyte solution, and the resolution index was performed to assess the experimental conditions; furthermore, a novel linear quantitative fingerprint method was established for accurate qualitative and quantitative discrimination of the test samples from diverse commercial brands. The fingerprint analysis coupled with quantitative determination of two components was employed to elucidate that the quality consistency of the products was relatively good within one manufactory, but poor among different companies for the 30 batches of samples. In addition, the fingerprint–efficacy relationship between chemical components and antioxidant activity in vitro was investigated using partial least squares analysis, and the calibration and prediction of the antioxidant activity of the selected samples via fingerprint data were presented with the desired results. This work illustrates that the proposed fingerprint analysis based on linear quantitative fingerprint method can be applied for the quality evaluation of traditional Chinese medicine and herbal preparations as part of their quality control, and the constructed mathematical model is particularly suitable for depicting the fingerprint–efficacy relationship.     

Identification of anti‐inflammatory active ingredients from Tumuxiang by ultra‐performance liquid chromatography/quadrupole time‐of‐flight‐MSE

The dried roots of Inula helenium L. (IH) and Inula racemosa Hook f. (IR) are used commonly as folk medicine as ‘tumuxiang’ (TMX). The mixing and sharing of IH and IR in clinical use is a universal phenomenon. Modern pharmacological studies confirmed that IH and IR display anti‐inflammatory activities. However, the difference in anti‐inflammatory pharmacodynamic substances between these two herbs is still unknown. In the present study, the fingerprints of 18 IH and nine IR samples were established using UPLC/QTOF‐MS^E. A dimethylbenzene‐induced mouse ear vasodilation model was applied in evaluating the anti‐inflammatory properties of all 27 samples. Then, the spectrum–efficacy model between chemical characteristic peaks and anti‐inflammatory activities was investigated using principal component regression and partial least squares. Finally, the combination of UNIFI Scientific Information System with a library search of traditional Chinese medicines was employed to automatically characterize the peaks. UNIFI identified a total of 80 chemical components. Among the components, the 53 characteristic peaks showed correlation with anti‐inflammatory activities, pointing to phenolic and organic acids as primary anti‐inflammatory ingredients of TMX. This approach can efficiently and intelligently facilitate the identification of bioactive components from traditional Chinese medicine.     

Studies on the Components of Crude and Processed Fructus Corni by ESI-MS

The components of crude and processed Fructus Corni were investigated by means of electrospray ionization-tandem mass spectrometry（ESI-MSn） technique in the negative ion mode. Compared with those of crude Fructus Corni, the chemical components of the processed Fructus Corni were changed both in quality and in quantity. From the ESI-MS spectra of the crude and processed Fructus Corni, six peaks were selected to establish the characte-ristic ESI-MS peaks. Several factors in the processing procedure were examined. The experimental results demonstrate that the chemical reactions that occurred in the processing procedure can be used for the elucidation of the processed mechanism of Fructus Corni, which is regularly affected by the processing conditions. The present article provides both the chemistry evidence for the understanding of the processing procedure of Fructus Corni and the specific methodology for the research of the processing procedure and quality identification of traditional Chinese medicine.     

Qualitative and quantitative analysis of pyrrolizidine alkaloids for the entire process quality control from Senecio scandens to Senecio scandens‐containing preparations by high performance liquid chromatography‐tandem mass spectrometry

Senecio scandens as a commonly used traditional Chinese medicine that is used alone or in combination with other herbs in preparations such as QianBai BiYan tablets has attracted much attention because of its hepatotoxic pyrrolizidine alkaloids. Nowadays, most studies for pyrrolizidine alkaloids are only performed on herbs or a preparation, however, production of preparations is a dynamic process, control of toxic impurities for raw materials, or finished products cannot monitor the production process dynamically. Thus, in this study, qualitative and quantitative analysis of pyrrolizidine alkaloids for the entire process quality control from S. scandens to its preparations was carried out with HPLC‐MS/MS for the first time, which was more comprehensive and dynamic than the previous single‐layer analysis. First, the species of pyrrolizidine alkaloids in S. scandens were analyzed, and the characteristic fragmentation rules of pyrrolizidine alkaloids containing common parent nucleus were found, which can be used to identify these components rapidly in the future. Then, a quantitative method for S. scandens to QianBai BiYan tablets and other nine S. scandens‐containing preparations was established, and after the medication safety speculation, all of them met the relevant safety requirements. After that, in order to ensure the stability and controllable of drug quality, the limit of pyrrolizidine alkaloids in preparations was determined according to the safe dosage that is stipulated to be the same as raw materials. Finally, the factors causing the content change of pyrrolizidine alkaloids in S. scandens from different source were studies, which can provide theoretical basis for selecting suitable raw materials for production.     

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.     

傅里叶变换红外光谱和傅里叶变换拉曼光谱法无损鉴别药材的真伪

利用傅里叶变换红外（FT-IR）和近红外傅里叶变换拉曼（NIR FT-aman）光谱法对大黄（西宁大黄）与伪品大黄（华北大黄、山大黄、水根大黄）进行了无损快速的鉴别。结果表明：尽管正品大黄与伪品大黄差别较小，有大部分的化学成分有很大的相同之处，但在红外、拉曼谱图中各自的特征峰较突出，根据谱峰的强度和位置可容易地将它们区别开来。红外和拉曼光谱法相互印证，相互补充，具有快速、准确、操作简单、重复性好、不需对样品进行分离提取，可直接鉴别等特点。