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Sophorae Flavescentis Radix,derived from the root of Sophora flavescens in the Leguminosae family,has been widely used in the medicine,agriculture,animal husbandry,and daily chemical industry. A pharmacophore model-based method for rapid discovery of tyrosinase inhibitors( TIs) from S. flavescens was established by molecular docking under Lipinski rules,and verified by enzyme assays. Briefly,the chemical constituent database of S. flavescens( CDSF) was established based on the previous papers. Theoptimal pharmacophore model( OPM) was constructed by DS 2019 on the basis of known active TIs. Eighty-three hits predominated by flavonoids having higher fitting scores with OPM than the positive control were screened out,and subjected to molecular docking based on the three-dimensional structure of tyrosinase crystal protein. The potential TIs such as kurarinone and nor-kurarinone were rapidly discovered from the compounds with higher docking scores than the positive control under the Lipinski rules. The results were verified by the in vitro enzyme assays. The inhibition activities of tyrosinase from non-medicinal parts of S. flavescens were also tested to explore the relationship between the inhibition activity and chemical compositions. This study is expected to provide data support for the comprehensive application and development of S. flavescens and also a new method for the rapid discovery of active substances or functional constituents in the complex systems.

As anti-aging ingredients, β-nicotinamide mononucleotide(NMN) and nicotinamide adenine dinucleotide(NAD~+) have attracted worldwide attention in recent years. After oral administration, NMN can be converted into NAD~+ in vivo and the latter is the actual ingredient which exerts anti-aging effect. In order to explore thequot;rejuvenating and anti-agingquot; effect of Dendrobium officinale, which was firstly recorded in Shennong's Herbal Classic of Materia Medica, this study established the quantitative method of UPLC-MS/MS for simultaneous determination of NMN and NAD~+ in D. officinale and the congeneric species for the first time, and 34 batches of samples were detected. UPLC conditions are as follows: ACQUITY UPLC HSS T3 column(2.1 mm × 100 mm, 1.8 μm), gradient elution with acetonitrile-0.1% formic acid in water at the flow rate of 0.3 mL·min~(-1), and column temperature of 40 ℃. MS conditions were scanned electrospray ionization source and multiple reaction monitoring mode. The method was verified by systematic methodology. The mean recoveries of NMN and NAD~+ were 77.58% and 80.70%, respectively, with RSD of 3.6% and 4.3%, separately. All results showed that the content of NMN was higher in D. officinale than in the other congeneric species. Particularly, the content in fresh D. officinale stems was as high as 0.931 9 μg·g~(-1). NAD~+ was only found in D. officinale and the content was three times higher than that of NMN. This may be the reason that D. officinale topped thequot;nine famous anti-aging herbsquot;. In addition, processing method influences the content of NMN and NAD~+ in Dendrobium. Specifically, the content of NMN and NAD~+ was in the order of fresh Dendrobium stemsgt; dried Dendrobium stem segmentsgt; spiral or spring-like dried Dendrobium stems.

Ethnopharmacological relevance Eucommia ulmoides (E. ulmoides) leaves are included in the Chinese Pharmacopoeia, and are traditionally used to treat hypertension, obesity, diabetes, and other diseases. Numerous pharmacological studies have shown that E. ulmoides has a good effect on lowering blood lipids and can improve obesity and nonalcoholic fatty liver. Aim To study the mechanism of E. ulmoides leaves in regulating nonalcoholic fatty liver disease by combining prediction and validation. Methods Using network pharmacology, and molecular docking to predict E. ulmoides in regulating the action mechanism and potential active ingredients of nonalcoholic fatty liver, large hole adsorption resin enrichment active sites, in vitro experiments were performed to verify its fat-lowering effect and mechanism. Results The major components of E. ulmoides leaves exhibited good combination with lipid metabolism-regulating core proteins, particularly flavonoids. EUL 50 significantly reduced lipid accumulation, and increased PPARγ. Compared with the control group, the autophagy level increased after the administration of EUL 50. PPARγ decreased significantly after the addition of chloroquine (CQ, autophagy inhibitor). Conclusion The active ingredients in E. ulmoides leaves regulating nonalcoholic fatty liver disease are mainly flavonoids and phenolics. EUL 50 may play a role in lowering lipids by regulating PPARγ expression through inducing autophagy.

This paper aims to solve the problems of complicated-unstable test solution preparation process and insufficient extraction of the active ingredient astragaloside Ⅳ in the legal method for the determination of astragaloside Ⅳ in Astragali Radix. The continuous single-factor analysis of seven main factors affecting the content of astragaloside Ⅳ was carried out by HPLC-ELSD, and then the pre-paration method of test solution was optimized. This optimized method exhibited excellent performance in precision, repeatability and stability. The average recovery rate of astragaloside Ⅳ was 99.65% with RSD 2.2%. Astragaloside Ⅳ showed a good linearity between the logarithm of peak area and the logarithm of injection quantity in the range of 0.46-9.1 μg(r=0.999 6). The contents of astragaloside Ⅳ in 29 batches of Astragali Radix were determined by the new and the legal methods. The results showed that the average content of astragaloside Ⅳ in these Astragali Radix samples determined by the former method was 1.458 times than that of the latter one, indicating the new method was simple, reliable and more adequate to extract target compound. According to the results, it is suggested to improve the content standard of astragaloside Ⅳ in Astragali Radix in the new edition of Chinese Pharmacopeia.

Taking Lonicerae Japonicae Flos as an example, the method ofquot;expert consensus of different regionsquot; was used to screen the representative samples and evaluate their commodity grades. The correlation analysis, hierarchical cluster analysis and partial least squares discriminant analysis(PLS-DA) ofquot;commodity grade-appearance characteristic-component contentquot; were carried out to reveal the scientificity of traditional commodity grade of Chinese medicinal material. By referring to the existing literature and the grade investigation from the sample collection regions, 78quot;initial gradequot; samples were screened out from 118 collected samples. Authoritative experts from four regions(n=4) including Linyi(Shangdong province), Bozhou(Anhui province), Anguo(Hebei province) and Beijing were organized to evaluate their commodity grades, separately. Based on the grade consistency rate(R_i≥70%), 69quot;local gradequot; samples were screened out from thequot;initial gradequot; samples. Based on the average grade consistency rate ■quot;authoritative gradequot; samples were screened out from thequot;local gradequot; samples, including15 first-grade samples, 9 second-grade samples, 11 third-grade samples and 17 fourth-grade samples. For thesequot;authoritative gradequot; samples, the main appea-rance characteristics were quantified and the contents of 13 components were determined by ultra performance liquid chromatography(UPLC). Furthermore, the total contents of 6 phenolic acids, 4 flavonoids and 3 iridoids were calculated, respectively. The results of correlation analysis showed that 4 appearance characteristics indices were correlated with the commodity grades: color, rate of yellow bars(including blooming flowers), rate of black heads(including black bars), and rate of stems and leaves(including bud debris). Five component content indices were correlated with the commodity grades: chlorogenic acid, isochlorogenic acid C, sweroside, loganin and the total contents of six phenolic acids. Furthermore, chlorogenic acid, loganin and the total contents of six phenolic acids showed significantly negative correlation with the main appearance characteristics, indicating that the appearance characteristics of Lonicerae Japonicae Flos can reflect its internal quality, and these 3 indices can be used as quality markers(Q-markers). The results of hierarchical cluster analysis showed that the samples of four grades were classified into four categories, and the samples with the same grades and the same categories accounted for 80.8% of the total samples, while the samples with the different grades were obviously classified into different categories. The results of PLS-DA analysis showed that the samples of different grades showed obvious intragroup aggregation and intergroup dispersion. The above results indicated that it was feasible to evaluate the traditional commodity grade of Lonicerae Japonicae Flos by the method ofquot;expert consensus of different regionsquot;. For the evaluation of traditional commodity grade of Chinese medicinal material, the samples should be representative, expert conclusions should have enough consensuses, and grade determination should be authoritative. As the crystallization of clinical experience, traditional commodity grade can scientifically reflect the internal quality of Chinese medicinal material.

Ethnopharmacological relevance The Dang-Gui-Si-Ni (DGSN) decoction as a classic prescription has been widely used for thousands of years in the clinical practice of traditional Chinese medicine (TCM). Especially in recent years, the potential efficacy of TCM for the treatment of Raynaud's syndrome has attracted great attention as there are still no specific remedies for this disease. However, the active constituents and underlying mechanisms responsible for the therapeutic benefits are not well understood, which makes it difficult to ensure quality control or to design research and drug development strategies. To identify the potential pharmacodynamic ingredients (PPIs) of TCM will help to achieve suitable process control procedures for industrial production and large-scale manufacturing. Aim of the study In the present study, we propose a multi-dimensional qualitative analysis method combining water-decoction spectra, in-vitro intestinal absorption spectra, in-vivo plasma spectra, and molecular docking of components to quickly identify the PPIs for the DGSN decoction of TCM. Materials and methods Water-based decoctions of DGSN were prepared in accordance with the clinical use registered in ancient books. Ultra-high-performance liquid chromatography-quadrupole-time of flight mass spectrometry (UHPLC-Q/TOF-MS) coupled with computerized modelling activity screening was used to quickly identify the PPIs of the DGSN decoction. Bioactive compounds absorbed in vitro were identified using the everted intestinal sac model from rats and compounds absorbed in vivo were confirmed in portal vein blood samples obtained following oral administration in rats. Molecular docking validation experiments were adopted to predict the binding activity to coagulation factors I, II, VII, X, and IX. The active components were further confirmed by pharmacodynamics analysis. The anticoagulant activity of the DGSN decoction was verified using rat models. Results Thirty-one compounds were identified in the DGSN decoction. According to the in vivo experiments, 22 compounds that could be absorbed in vivo were detected by the everted intestinal sac model in rats. This model greatly reduces the scope of PPIs and is easy to perform. Ten compounds were detected in the portal vein blood in rats. The compounds detected in plasma provide stronger evidence supporting the PPIs. Molecular docking in vitro experiments indicated that 7 compounds exhibited better binding activity with coagulation factors I, II, VII, X, and IX. The animal experiments confirmed that the DGSN decoction could improve the microcirculation, providing indirect proof of anticoagulant activity suggested by the molecular docking studies. Finally, based on the multi-dimensional methods, 9 potential compounds present in the DGSN decoction were identified as PPIs (i.e., ferulic acid, paeoniflorin, albiflorin, chlorogenic acid, cryptochlorogenic acid, liquiritin, liquiritin apioside, cinnamaldehyde and glycyrrhizic acid). Conclusion Overall, this study combined the water-decoction spectra, intestinal absorption spectra in vitro, plasma spectra in vivo, and molecular docking studies to establish a multi-dimensional qualitative analysis method of the DGSN decoction. Meanwhile, 9 compounds in DGSN decoction were identified as PPIs using this method, and are proposed for application as quality standards for complex TCM prescriptions.

This paper takes a marine steam turbine control valve as the research object, studies the vibration response under pressure pulse excitation. First, the transient flow field analysis is made to obtain the time-domain information of the pressure pulsation; Followed by pressure pulsations fast Fourier transform into the frequency domain information, access to the load spectrum; Then modal analysis is studied to obtain the natural frequencies and mode shapes; Finally, based on the analysis of vibration modes, research vibration response and resonance problems of control valve. The study found that the vibration of control valve is strongly in low frequency excitation, but high-frequency excitation makes relatively little impacts on it; The diffuser and downstream of valve is the main area of generating vibration. Supported by the Fundamental Research Funds for the Central Universities (HEUCF140707).

The instability flow in the control valve often lead to abnormal vibration, the valve wear and the valve stem destruction, also lead to pressure loss. The flow in the control valve show complex flow regime distribution and variation, it is a typical unsteady flow. Therefore, it is necessary to theoretical calculation and qualitative analyses the flow field of valve by the numerical simulation method. In this paper, we study on the axial force of valve stem that caused by the fluid pulsation pressure. Establishing the flow field model of the control valve, generating the computational grid through the pre-processor, using the CFD software to do discretized and solved, getting visualization graphics of the internal flow field. Study the changes of the flow characteristics according to different pressure ratio, getting the variation characteristic of axial force. Provide the basis for subsequent optimization and design of the low vibration control valve.