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Baicalin concentration is concerned in manufacture of scutellaria spray drying powder as a traditional Chinese medicine, and the quality control based on high‐performance liquid chromatography is inconvenience. In this study, terahertz time domain spectroscopy was employed to achieve quality control of scutellaria spray drying powder; however, an acute difficulty was found that terahertz spectra overlapped due to the disturbance in both content matrix and measurement error. In this study, similar terahertz spectra of scutellaria spray drying powder were classified with the help of Gaussian mixture model and built a classifier based on probability feature instead of spectral features conventionally employed in previous investigations. To explore the feasibility of GMM, principal component analysis was given, indicating that it is possible to train GMM with original features and proper principal components. Probable advantage of training GMM based on PCA feature was discussed and so it was with the capacity of the model to identify the linear combined spectra by comparing the performance of GMM and a decision tree model. Above all, the reason why GMM shows potential in the analysis of TCM terahertz spectra was illustrated by comparing the thought of discriminative model and generative model. This study implied that generative model may have natural advantage of overcoming the inherent disturbance of terahertz spectroscopy, which would be promising in future studies. [ABSTRACT FROM AUTHOR]

Introduction: Calculus bovis (C. bovis) is a typical traditional Chinese medicine (TCM) derived from animals, which has a remarkable curative effect and high price. Objectives: Rapid identification of C. bovis from different types was realized based on spectral technology, and a rapid quantitative analysis method for the main quality control indicator bilirubin was established. Methods: We conducted a supervised and unsupervised pattern recognition study on 44 batches of different types of C. bovis by five spectral pretreatment methods. Three variable selection methods were used to extract the essential information, and the partial least squares regression (PLSR) quantitative model of bilirubin by near‐infrared (NIR) spectroscopy was constructed. Results: The partial least squares discriminant analysis (PLS‐DA) model could achieve 100% accuracy in identifying different types of C. bovis. The R2 of the NIR quantitative model was 0.979, which is close to 1, and the root mean square error of calibration (RMSEC) was 2.3515, indicating the good prediction ability of the model. Conclusion: The study was carried out to further improve the basic data of quality control of C. bovis and help the high‐quality development of TCM derived from animals. A comprehensive study of C. bovis of animal origin by spectroscopic and chromatographic techniques. [ABSTRACT FROM AUTHOR]

Salvia miltiorrhiza, a plant in the Labiatae family, is a traditional Chinese herb. The small molecular components in S. miltiorrhiza can be divided into tanshinones and salvianolic acids, which have anti-inflammatory and anti-apoptotic effects by inhibiting the expression of inflammatory factors such as tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β), interleukin-6 (IL-6) and some apoptosis factors. At the same time, these components can also play a protective effect on cardiomyocytes by activating Akt/ERK1/2/Nrf2 pathway, JAK2/STAT3 pathway, PI3K /Akt and Erk1/2 pathway. Moreover, polysaccharide is one of the main macromolecule active components of S. miltiorrhiza, which plays an antioxidant and myocardial protective role by reducing myocardial malondialdehyde, serum creatine kinase (CK) and lactate dehydrogenase (LDH) levels. Meanwhile, The above mechanisms are also the main way in which the clinical resistance of S. miltiorrhiza to cardiovascular disease. This study reviewed the mechanism and clinical application of the main medicinal components of S. miltiorrhiza in myocardial infarction. [ABSTRACT FROM AUTHOR]

Introduction: The quality evaluation of Coptidis rhizome (CR) is attributed to the origin and processing method, and this strategy of ignoring the bioactive components usually leads to biased quality analysis, which is difficult to indicate the clinical efficacy. Objectives: In order to evaluate the quality level of different species of CR, we collected 20 batches of CR and investigated the fingerprint‐effect relationship. Methods: High‐performance liquid chromatography (HPLC) fingerprints of CR were established, and the fingerprint‐effect relationship was explored using cluster analysis, principal component analysis, Pearson correlation analysis, grey relation analysis, and partial least squares regression. Results: We have identified a total of 10 common peaks (1–10) with similarity scores above 0.96. The study on the relationship between spectra and potency further showed that the contents of peaks 8, 9, and 10 are potential key components. And based on a previous study, a method of one measurement and multiple evaluations of CR was established to achieve the goal of simplifying the analytical process and reducing costs. Conclusion: Through a combination of fingerprint analysis, antioxidant activity evaluation, fingerprint‐efficacy relationship analysis, and simultaneous quantification of multiple components, a CR quality control index and method have been selected and established, which can also provide a more comprehensive quality evaluation for traditional Chinese medicine. Quality analysis of different species of Coptidis rhizome was conducted through antioxidant activity and fingerprint analysis methods. [ABSTRACT FROM AUTHOR]

Rebaudioside A (RA) is an ideal sweet component extracted from leaves of Stevia rebaudiana Bertoni and has been widely used in the food and pharmaceutical fields. Macroporous adsorbent resin is often used to enrich RA due to its low cost, easy regeneration, and high stability. However, the traditional method for the determination of the elution process end point often relies on personal experience, which has hysteresis and ambiguity and seriously restricts the broad development prospects of stevia. To develop a new method for rapidly and accurately determining the RA content in the macroporous resin elution process, portable near-infrared (NIR) spectroscopy combined with chemometrics was used in this study. The linear partial least squares regression (PLSR) model and the non-linear support vector machine regression (SVMR) model were used to establish the relationships between the NIR spectrum and the RA content. The results of model fitting showed that the PLSR model displayed higher predictive accuracy of the RA content than the SVMR model with a determination coefficient external test set (Rp2) value of 0.9796, a root mean square error external test set (RMSEP) value of 2.7555 and a residual prediction deviation (RPD) value of 6.5566. This study demonstrates that NIR spectroscopy techniques are potential tools for rapidly determining the RA content in the macroporous resin elution process, which will save time, effort, and cost in the analysis of large quantities of unknown samples. [ABSTRACT FROM AUTHOR]

In this work, the preparative separation of quinolyridine alkaloids from seeds of T. lanceolata by conventional and pH‐zone‐refining counter‐current chromatography. Traditional counter‐current chromatography separation was performed by a flow‐rate changing strategy with a solvent system of ethyl acetate‐n‐butanol‐water (1:9:10, v/v) and 200 mg sample loading. Meanwhile, the pH‐zone‐refining mode was adopted for separating 2.0 g crude alkaloid extracts with the chloroform‐methanol‐water (4:3:3, v/v) solvent system using the stationary and mobile phases of 40 mM hydrochloric acid and 10 mM triethylamine. Finally, six compounds, including N‐formylcytisine (two conformers) (1), N‐acetycytisine (two conformers) (2), (‐)‐cytisine (3), 13‐β‐hydroxylthermopsine (4), N‐methylcytisine (5), and thermopsine (6) were successfully obtained in the two counter‐current chromatography modes with the purities over 96.5%. Moreover, we adopted nuclear magnetic resonance and mass spectrometry for structural characterization. Based on the obtained findings, the pH‐zone‐refining mode was the efficient method to separate quinolyridine alkaloids relative to the traditional mode. [ABSTRACT FROM AUTHOR]

A novel acylated quercetin glycoside, floralpanasenoside A (1) and five known flavonoid glycosides, panasenoside (2), quercetin 3-O-(2''-β-D-glucopyranosyl)-β-D- galactopyranoside (3), trifolin (4) kaempferol 7-O-α-L-rhamnoside (5), and afzelin (6) were isolated from the flower buds of Panax ginseng. Their structures were established by spectroscopic data and comparison with the literature values. Four of the six isolated compounds including 1 (IC50 = 62.4) exhibited α-glucosidase inhibitory activity with IC50 values lower than acarbose (385.2 μM). The molecular docking study indicated that 1 bound to the active site of α-glucosidase with numerous hydrogen bond interactions. [ABSTRACT FROM AUTHOR]