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Ethnopharmacological relevance The flower of Edgeworthia gardneri (Wall.) Meisn., locally named “Lvluohua, 绿萝花”, has been widely used as Tibetan folk medicine for the treatment of metabolic diseases for a long time. Aim of this study To evaluate the anti -adipogenesis effect of ethyl acetate extract of the flower of E. gardneri (EEG extract) in 3T3-L1 adipocytes. Materials and methods Obesity-related parameters such as lipid accumulation and TG content were determined by Oil red O staining and enzymatic kit, respectively. Western blotting was used to determine the expressions of peroxisome proliferator-activated receptor γ (PPARγ), CCAAT/enhancer-binding protein-α (C/EBPα), phosphorylated adenosine 5′-monophosphate (AMP)-activated protein kinase (AMPK) and acetyl-CoA carboxylase (ACC). Moreover, main constituents of EEG extract were analyzed by high performance liquid chromatography (HPLC). Results EEG extract decreased the lipid and triglyceride (TG) accumulations during the differentiation process and down-regulated the adipogenesis-related transcriptional factors PPARγ and C/EBPα. EEG extract treatment increased AMPK and ACC phosphorylation. In addition, pretreatment with AMPK inhibitor, weakened the inhibitory effects of EEG extract on the expressions of PPARγand C/EBPα. HPLC analysis indicated that tiliroside was the main constituent in EEG extract. Conclusions These results suggest that EEG extract may exert anti-adipogenic effects through modulation of the AMPK signaling pathway. [ABSTRACT FROM AUTHOR]

Yolk-shell structure magnetic metal–organic framework nanoparticles were prepared via post solvothermal method and employed as a magnetic solid-phase extraction adsorbent for selective pre-concentration of 5′-ribonucleotides by π stacking interaction, hydrogen bonding, and the strong interaction between titanium ions (Ti4+) and phosphate group. The properties of the materials were confirmed by scanning electron microscopy, transmission electron microscopy, X-ray diffraction, X-ray photoelectron spectrometry, vibrating sample magnetometer, infrared spectroscopy, thermogravimetric analysis, and Brunauer–Emmett–Teller analysis. The main parameters affecting the adsorption–desorption process, including adsorbent amount, incubation time, incubation temperature, sample pH, shaking speed, elution solution, and elution time, were systematically optimized. Finally, 1.0 mg of adsorbent mixed with 1.0 mL sample solution (10.0 mmol⋅L−1 NaCl, pH 3.0) and shaken at 135 rpm for 5 min at 40 °C, washed with 1.0 mL Na3PO4-NH3∙H2O under vortex for 5 min were selected as optimized adsorption–desorption conditions. The binding performance of adsorbent towards five nucleotides was evaluated by static adsorption experiments. The data are well-fitted to the Langmuir isotherm model and the maximum adsorption capacity is 27.8 mg g−1 for adenosine 5′-monophosphate. The limit of detection of the method is 19.44–38.41 ng mL−1. Under the optimal conditions, the adsorbent was successfully applied to magnetic solid-phase extraction and high performance liquid chromatography determination of five nucleotides in octopus, chicken, fish, and pork samples. [ABSTRACT FROM AUTHOR]

In this study, a zirconium terephthalate metal‐organic framework‐coated magnetic nanoparticle (UiO‐66@PA@PEI@Fe3O4) was synthesized for the extraction of berberine prior to high‐performance liquid chromatography analysis. The phytic acid, which could be grafted onto the magnetic nanoparticle through electrostatic interaction with the abundant amino groups of polyethylenimine, possesses outstanding metal ion coordination ability for the immobilization of metal‐organic frameworks UiO‐66. The physicochemical properties of the obtained nanoparticle were thoroughly investigated by a series of characterization techniques. Then, the factors that will affect the extraction efficiency and recovery of berberine were investigated. Results indicated that the material had good stability and reusability, and high adsorption capacity (50.01 mg/g) to berberine through single‐layer adsorption. In addition, a molecular docking study indicated that the interactions between the material and berberine were mainly π‐π stacking and hydrophobic interaction. Finally, the material was successfully applied to the extraction of berberine in Rhizoma Coptidis and Cortex Phellodendri extracts with the recoveries of 76.1% and 71.6%, respectively. [ABSTRACT FROM AUTHOR]

Capillary electrochromatography, which combined the high selectivity of high‐performance liquid chromatography and the high separation efficiency of capillary electrophoresis, is an attractive separation tool. In this review, the developments on monolithic and open tubular capillary electrochromatography during 2017 to August 2019 are summarized. Considering the development of novel stationary phases is the most active research field in capillary electrochromatography, monolithic capillary electrochromatography is classified according to the polymer‐based and hybrid monolithic columns, while open‐tubular capillary electrochromatography is categorized by cyclodextrin, silica, polymer, nanomaterials, microporous materials, and biomaterials‐based open tubular columns. [ABSTRACT FROM AUTHOR]

Tyrosinase (TYR) is a rate-limiting enzyme in the synthesis of melanin, while direct TYR inhibitors are a class of important clinical antimelanoma drugs. This study established a spectrum-effect relationship analysis method and high-performance liquid chromatography-mass spectrometry (LC-MS) analysis method to screen and identify the active ingredients that inhibited TYR in Salvia miltiorrhiza–Carthamus tinctorius (Danshen–Honghua, DH) herbal pair. Seventeen potential active compounds (peaks) in the extract of DH herbal pair were predicted, and thirteen of them were tentatively identified by LC-MS analysis. Furthermore, TYR inhibitory activities of five pure compounds obtained from the DH herbal pair were validated in the test in which kojic acid served as a positive control drug. Among them, three compounds including protocatechuic aldehyde, hydroxysafflor yellow A, and tanshinone IIA were verified to have high TYR inhibitory activity (IC50 value of 455, 498, and 1214 μM, resp.) and bind to the same amino acid residues in TYR catalytic pocket according to the results of the molecular docking test. However, the other two compounds lithospermic acid and salvianolic acid A had a weak effect on TYR, as they do not combine with the active amino acid residues or act on the active center of TYR. Therefore, the developed methods (spectrum-effect relationship analysis and molecular docking) could be used to effectively screen TYR inhibitors in complex mixtures such as natural products. [ABSTRACT FROM AUTHOR]

Thrombin (THR) plays a significant role in thromboembolic diseases, direct THR inhibitors are a class of important clinical anticoagulant drugs. This study established a THR in-solution based biospecific extraction combined with ultrafiltration and high performance liquid chromatography coupled with diode array detector and mass spectrometry analysis (TUA) method to screen and identify ligands for THR in Rhizoma Chuanxiong. After evaluating the reliability of the present TUA method using positive (argatroban) and negative (adenosine, tirofiban, ticagrelor) control drugs, this method was successfully applied to detect eight potential active compounds in Rhizoma Chuanxiong. Two new THR-targeted compounds isochlorogenic acid C and senkyunolide I with high THR inhibitory activity (IC50 206.48 and 197.23 μM, respectively) were identified by liquid chromatography/mass spectrometry and enzyme inhibitory activity test finally. They were reported with direct THR inhibition activity for the first time and their ligand-THR interactions were explored by in silico molecular docking research. In addition, based on the TUA screening result, four compounds gained similar structure with the two hit compounds were also investigated as promising candidates targeting THR with high binding energy (>5.0 kcal/mol). These results may prove that the proposed method could effectively screen THR inhibitors in complex mixtures. [ABSTRACT FROM AUTHOR]

Salvia miltiorrhiza (Danshen, DS), the dried root and rhizome of Salvia miltiorrhiza Bunge and Ligusticum chuanxiong (Chuanxiong, CX), the dried rhizomes of Ligusticum striatum DC are effective in invigorating blood circulation and eliminating stasis which is highly related with cardiovascular disease (CVD). The identification of activity-based chemical markers is very important, but the complex mechanism of "multi-component, multi-target, and multi-effect" within traditional Chinese medicine (TCM) poses a great challenge to this work. In this study, we combined network pharmacological prediction with experimental validation of the DS and CX to explore an effective method for discovering quality control (QC) of antithrombotic herbs by clarifying the intermediate layer "module/cluster" between the whole complex system and a single component. Based on structural similarity analysis of compound and the thrombosis network published before, we firstly modularized two layers called chemical cluster (CC) network and functional module (FM) network respectively and linked them into one bilayer modularized compound target (BMCT) network. "Two-step" calculation was applied on identifying the significant compounds as the potential QC markers from CC. The in vitro inhibitory activity of selected QC marker compounds on thrombin was evaluated to partially verify their pharmacological activities. HPLC was used to determine contents. According to the network-based analysis, nine compounds with great importance in the BMCT network were identified as QC markers of DS-CX, including tanshinone I, tanshinone IIA, cryptotanshinone, salvianolic acid B, ferulic acid, salvianolic acid A, rosmarinic acid, chlorogenic acid, and coniferyl ferulate. Enzyme inhibitory test partially verified the activity of tanshinone I and tanshinone IIA. Chemical profiling indicated that the nine marker compounds are the main components in the herbal pair. This study identified activity-based QC markers of DS-CX herbal pair and provided a new methodology that can be used in the QC of other herbs, herbal pairs, or formulas. [Display omitted] [ABSTRACT FROM AUTHOR]