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Vine tea has been used as an herbal tea by several ethnic minorities for hundreds of years in China. Flavonoids, a kind of indispensable component in a variety of nutraceutical, pharmaceutical and cosmetic applications, are identified to be the major metabolites and bioactive ingredients in vine tea. Interestingly, vine tea exhibits a wide range of significant bioactivities including anti-oxidant, anti-inflammatory, anti-tumor, antidiabetic, neuroprotective and other activities, but no toxicity. These bioactivities, to some extent, enrich the understanding about the role of vine tea in disease prevention and therapy. The health benefits of vine tea, particularly dihydromyricetin and myricetin, are widely investigated. However, there is currently no comprehensive review available on vine tea. Therefore, this report summarizes the most recent studies investigating bioactive constituents, pharmacological effects and possible mechanisms of vine tea, which will provide a better understanding about the health benefits and preclinical assessment of novel application of vine tea., Graphical abstract Image 1, Highlights • Vine tea has been consumed as a folk herbal tea for hundreds of years. • Flavonoids were the major bioactive ingredients in vine tea. • Dihydromyricetin and myricetin are major bioactives in vine tea. • Vine tea exhibits a wide range of significant bioactivities. • Vine tea may be a potential, functional herbal tea.

The chaperone-assisted soluble expression and characterization of high molecular weight chitinase chiZJ408 in Escherichia coli BL21 were investigated. Chitin degradation products by chitinase chiZJ408 were analyzed. The results indicated that the introduction of the chaperone GroELS promoted the correct folding of chitinase chiZJ408 and increased its soluble expression by 14.9% (p < 0.05) in E. coli BL21. The optimal pH and temperature of chitinase chiZJ408 were respectively 6.0 and 50 °C. Chitinase chiZJ408 was stable at pHs of 4.0 ∼ 7.0 and at below 40 °C. Mg2+and Ca2+ had a significant impact on improving the activity of chitinase chiZJ408. Chitinase chiZJ408 was demonstrated to be exochitinase that cleaved the β-1,4-glycosidic bond of the chitin chain to generate only N,N'-diacetylchitobiose. This study broadens our understanding of chitinase and provides a basis for solving the problem of inclusion body formed by long fragment gene expression in E. coli.

In this work, gold nanoparticles were biosynthesized via Plectranthus amboinicus leaf extract as the reducing agent. A series of techniques were used for sample analysis. The biosynthesized gold nanoparticles (bAuNPs) are a uniform size with a spherical shape. The FTIR analysis reveals the presence of many oxygen-containing functional groups on the bAuNP surface. The cyclic voltammetry and electrochemical impedance spectroscopic characterizations reveal that while the bAuNPs have a slightly lower conductivity than chemically synthesized AuNPs (cAuNPs). However, the bAuNPs have a superior electrocatalytic performance toward nicotine reduction. After optimization, the bAuNP-modified SPE could detect nicotine linearly from 10 to 2,000 μM with a low detection limit of 2.33 μM. In addition, the bAuNPs/SPE have been successfully used for nicotine-containing-product analysis.

s 2-(2-Hydroxypropanamido) benzoic acid (HPABA) is a potential anti-inflammatory agent isolated from the marine fungus Penicillium chrysogenum . In vivo tissue distribution and excretion of HPABA were unknown. Therefore, the purpose of this paper was to establish an UHPLC–MS/MS method for the determination of HPABA and proceed to apply for the study of tissue distribution and excretion in rats. The results obtained indicated that HPABA in tissues was rapidly distributed and cleared. The highest level was found in intestine and stomach, followed by kidney, liver, lung and heart. These observations showed that HPABA was well distributed into abundant blood-supply tissues, suggesting that the blood flow or perfusion rate of organs plays a major role. A small amount of HPABA was detected in brain indicated that the ability of it in crossing the blood brain barrier (BBB) was very weak in rats. Excretion studies demonstrated that HPABA was mainly excreted by kidney. The total cumulative excretion of HPABA were 54.3% and 44.1% in male and female rats, respectively. In addition, gender-related differences in the excretion and distribution profile of HPABA were observed in rats.

Unravelling the surface physical and chemical properties, especially the surface activity of Pu-oxides (PuO2, α-Pu2O3) toward molecules, is essential to the long-term storage and surface reaction of Pu. Within DFT+U-D3 scheme, we systematically investigate the adsorption behaviors of H2O and CO2 on α-Pu2O3(111) surface, and clarify the different chemical activity of α-Pu2O3(111) surface from PuO2(111), which is due to the distinct coordination and bonding property of the top-layer Pu. There are five- and six-coordinated Pu (Pu5c, Pu6c) on α-Pu2O3(111) surface, among which Pu5c is more reactive with lower work-function than Pu6c. Interestingly, H2O and CO2 present the preferential adsorption at the Pu5c sites rather than Pu6c, namely, the site-selective adsorption. H2O tends to dissociate spontaneously and adsorb in cluster as with the coverages increase, while CO2 keeps the molecular state adsorption. The calculated phase diagram and isotherm indicate that the adsorption quantity and stability of H2O are higher than CO2 at the same (T, P) condition, and CO2 can achieve the multilayer adsorption at high pressure (PCO2). This work reveals the chemical heterogeneity of α-Pu2O3(111) surface and the selective adsorption mechanism of active molecules, which clearly depicts the interactions between environment gaseous and Pu-oxide surfaces.

Viscum coloratum is a perennial evergreen, semi-parasitic plant. It is generally used for treating cardiovascular diseases, cancer, hepatitis and hemorrhage. In this study, reliable methods were developed for the qualitative and quantitative analysis of the common constituents in Viscum coloratum and its corresponding host. In the rapid qualitative analysis, a method of ultra-high performance liquid chromatography and quadrupole time-of-flight tandem mass spectrometry was established for identification of the same compounds. Based on the retention times, accurate mass measurement and previous literatures, 23 components were clearly identified by comparison with reference substances. In the quantitative analysis, a method for Viscum coloratum and its corresponding host was developed by ultra-high performance liquid chromatography with triple quadrupole mass spectrometry. 13 common compounds of viscum coloratum and host plants from 19 batches were analyzed with a good linearity (r2≥0.9991), intra-day precision (RSD≤3.24%), inter-day precision (RSD≤3.31%), repeatability (RSD≤2.43%), stability (RSD≤2.63%), and recovery (98.2-102.4%). The overall limits of quantification were less than 5.0ng/mL. The results indicated that these effective and comprehensive methods can be applicable to simultaneous qualitative and quantitative analysis of these common compounds presented in Viscum coloratum and corresponding host plants.

The main polyphenols in mung bean (Vigna radiata L.) seed (MBS), an edible legume with various biological activities, are C-glycosyl flavones (vitexin, isovitexin, isovitexin-6″-O-α-l-glucoside, and dulcinoside). In our study, a validated ultrahigh-performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) method was developed to quantitate the concentrations of four C-glycosyl flavones from MBS extracts in the plasma and various tissues of rats and successfully applied to study their pharmacological profile and tissue distribution in vivo. Four C-glycosyl flavones were rapidly absorbed after oral administration, achieving a Cmax at around 1.5 h, and they could be distributed widely and rapidly in tested tissues. The concentrations of four C-glycosyl flavones in all of the tested tissues decreased obviously in 4 h, which indicated that there was not a trend of long-term accumulation of them. This is the first time to report on pharmacokinetic and tissue distribution studies of four C-glycosyl flavones in rat. The results provided a significative basis for the application of MBS.

The adsorption thermodynamics of active molecules on PuO2 surface are very important for the long-term storage and surface corrosion of Pu. Here, a comparative study is performed within DFT+U-D3 scheme to investigate the adsorption mechanisms, morphology, and phase diagrams of H2O and CO2 on PuO2(1 1 1) surface. The adsorption morphology of H2O will transition from the molecular state to a mixed adsorption state when the coverage is increasing, but CO2 always adsorbs in the molecular state. The differences in adsorption behaviors are mainly due to the hydrogen bonds and Coulomb interactions between the adsorbed molecules. The hydrogen bonds promote the polymolecular adsorption of H2O and the further partial dissociation at high coverage. The Coulomb attractive force among H2O is larger than CO2, and the attractive force among CO2 rapidly decreases as the coverage increases. Unlike the multilayer BET model of H2O adsorption, CO2 adsorption accords with monolayer Freundlich model as revealed by the calculated isotherms. The desorption temperature (Tdes) of H2O and CO2 are agreeing with the experimental results, and the Tdes of H2O is lower than CO2 at the same pressure. This work clarifies the adsorption behaviors of H2O and CO2, and it could provide some important insights into the prediction of the surface corrosion reactions of PuO2 in storage containers.

A sensitive and selective ultra high performance liquid chromatography with tandem mass spectrometry method was established and validated for the simultaneous determination of hydroxy-α-sanshool, hydroxy-β-sanshool, and hydroxy-γ-sanshool in rat plasma after the subcutaneous and intravenous administration of an extract of the pericarp of Zanthoxylum bungeanum Maxim. Piperine was used as the internal standard. The analytes were extracted from rat plasma by liquid-liquid extraction with ethyl acetate and separated on a Thermo Hypersil GOLD C18 column (2.1 mm × 50 mm, 1.9 μm) with a gradient elution system at a flow rate of 0.4 mL/min. The mobile phase consisted of acetonitrile/0.05% formic acid in water and the total analysis time was 4 min. Positive electrospray ionization was performed using multiple reaction monitoring mode for the analytes. The calibration curves of the three analytes were linear over the tested concentration range. The intra- and interday precision was no more than 13.6%. Extraction recovery, matrix effect, and stability were satisfactory in rat plasma. The developed and validated method was suitable for the quantification of hydroxy-α-sanshool, hydroxy-β-sanshool, and hydroxy-γ-sanshool and successfully applied to a pharmacokinetic study of these analytes after subcutaneous and intravenous administration to rats.

The polarons induced by interactions between excess charges and lattice distortions play an important role in surface chemical reactivity of actual oxides. The impacts of electron and hole polarons on H2O and CO2 adsorptions on PuO2(111) surface are investigated by first-principles DFT+U-D3 calculations. Our study reveals that surface and subsurface electron/hole polarons play different roles to H2O and CO2 adsorption. Surface polarons can promote H2O and CO2 adsorption, specifically, electron polarons tend to promote H2O adsorption much more, and hole polarons tend to facilitate CO2 adsorption. We find it interesting that the subsurface electron polaron can promote H2O but depress CO2 adsorption, whereas the subsurface hole polaron play quite an opposite role. Based on a careful study on the electronic and atomic structures of the defective PuO2(111) surfaces, we put forward the inverse modulation mechanism by subsurface electron and hole polarons on H2O and CO2 adsorption, which could shed some light on how to manipulate the molecular adsorption on oxide surfaces.

The in-depth understanding of hydrogen permeation through plutonium-oxide overlayers is the prerequisite to evaluate the complex hydriding induction period of Pu. In this work, the incorporation, diffusion and dissolution of hydrogen in α-Pu2O3 are investigated by the first-principles calculations and ab initio thermodynamic method based on DFT+U and DFT-D3 schemes. Our study reveals that the hydrogen incorporation is endothermic and the separated H atoms prefer to recombine as H2 molecules rather than reacting with α-Pu2O3. The H and H2 diffusion are both feasible, generally, H will recombine first as H2 and then migrate. Both pressure PH2 and temperature T can promote the hydrogen dissolution in α-Pu2O3. The single H2 molecule incorporation and (H + H2) mixed dissolution will successively appear when increasing PH2. Compared to PuO2, this work indicates that Pu sesquioxide is hardly reduced by hydrogen, but the porous α-Pu2O3 facilitates hydrogen transport in Pu-oxide layers. We present the microscopic picture of hydrogen behavior in the defect-free α-Pu2O3, which could shed some light on the study of the hydriding induction period of Pu.

A selective, sensitive and fully validated liquid chromatography-tandem mass spectrometry (LC-MS/MS) method was established for the determination of dihydromyricetin, dihydroquercetin, myricetin and quercetin in rat plasma after intragastric administration of Hoveniae Semen total flavonoids. Baicalin was selected as the internal standard. Analytes were extracted from the rat plasma by protein precipitation with acetonitrile and separated on a C18 chromatographic column (Agilent ZORBAX Eclipse Plus, 4.6 mm × 100 mm, 3.5 μm) using the mobile phase containing acetonitrile (A) and 0.1% formic acid-water (B) by gradient elution at 0.5 mL/min flow rate. A tandem mass spectrometer equipped with an electrospray ionization (ESI) source was used to detect analytes. The analytes were measured by multiple reaction monitoring (MRM) in the negative ionization mode. The lower limit of quantification of dihydromyricetin, dihydroquercetin, myricetin and quercetin were 0.70, 8.16, 1.62 and 0.56 ng/mL, respectively. The accuracy, intra-day and inter-day precision and recovery were all satisfactory and the compounds were stable in rat plasma under all tested conditions. The approach was successfully applied to study pharmacokinetic characteristics of the four bioactive flavonoids in plasma after administering Hoveniae Semen total flavonoids intragastrically to rat. Further investigation was carried out to assess pharmacokinetic comparability of the four bioactive flavonoids after intragastric administration of Hoveniae Semen total flavonoids to mixture of flavonoids.

Incompatible herb pair Gansui-Gancao is recorded in "eighteen incompatible" medicaments in many monographs of TCM (Traditional Chinese Medicine) which means the two herbs can not be co-used in most cases. However, Gansuibanxia decoction composed of Gansui(Kansui), Banxia(Pinellia), Shaoyao(Peony) and Gancao(Liquorice) is a traditional Chinese formula which has been clinically employed for the treatment of cancerous ascites, pleural effusion, peritoneal effusion, etc. The purpose of the study was to investigate the pharmacokinetics of main bioactive components in Gancao to explore the reasons why Gansui-Gancao can be used in Gansuibanxia decoction. A simple, rapid and sensitive UHPLC-MS/MS method for simultaneous determination of liquiritigenin, isoliquiritigenin, liquiritin, glycyrrhetinic acid and glycyrrhizic acid of liquorice in rat plasma was developed and validated. After extraction from plasma, the analytes and internal standard were separated on a C18 column with the mobile phase consisting of 0.1% acetic acid containing 0.2 mM ammonium acetate in water and acetonitrile via gradient elution. The electrospary ionization source was adopted under the multiple reaction monitoring mode. The method was succesfully applied to a comparative pharmacokinetic study of main bioactive components of Gancao in rat plasma after oral administration of the extracts of Gancao (GC), Gansui-Gancao (GS-GC), Shaoyao-Gancao (SY-GC), Gansui-Shaoyao-Gancao (GS-SY-GC) and Gansuibanxia decoction (GSBXD), respectively. The pharmacokinetic parameters had significant differences (P 0.05) in different groups which showed that Gansui decreased the bioavailability of Gancao, while Shaoyao increased the bioavailability of Gancao. Hence, these may be the pharmacokinetic mechanism of incompatible herb pair Gansui-Gancao and the reasons why the herb pair can be used in Gansuibanxia decoction.

As the stereoselective plasma protein binding is an important factor for the differences in pharmacokinetic or pharmacodynamic properties of chiral drugs, we elucidated the binding of (R)-/(S)-HPABA to plasma protein. A UHPLC–MS/MS method was developed and validated to the quantitation and equilibrium dialysis method was applied to the separation of bound and unbound drugs. Protein binding reached equilibrium within 12 h of incubation at 37 °C. Liquid-liquid extraction with ethyl acetate was used for sample preparation. The separation was achieved through a Thermo Syncronis C18 column (50 mm × 2.1 mm, 1.7 μm; Thermo, USA) using gradient elution at a flow rate of 0.4 ml/min. All of the recovery and matrix effect of the method met the requirements of analytical method validation. The plasma protein binding of (R)-/(S)-HPABA show significant species dependence in enantioselectivity. In addition, the results of molecular docking showed that the combining capacity of (R)-HPABA with HSA was higher than that of (S)-HPABA.

A simple and sensitive UHPLC–MS/MS method was developed and validated to determine the pharmacokinetic profile of 2-(2-hydroxypropanamido) benzoic acid (HPABA) enantiomers and their prodrugs in rat plasma. Separation was performed on a Thermo Syncronis C 18 column (50 mm × 2.1 mm, 1.7 μm; Thermo, USA), which was protected by a high pressure column prefilter (2 μm) at a flow rate of 0.4 ml/min. Liquid-liquid extraction with ethyl acetate was used to process plasma samples. The separation of two enantiomers, prodrugs of ( R ) -/ ( S )-HPABA and internal standard was obtained within a cycle time of 4.5 min. The lower limit of quantification of ( R ) -/ ( S )-HPABA and prodrugs of ( R ) -/ ( S )-HPABA in plasma were 0.01 μg/ml and 0.2 μg/ml, respectively. ( S )-HPABA showed significantly higher AUC, C max and a longer t 1/2 than ( R )-HPABA, indicating higher bioavailability of the ( S )-HPABA. Additionally, inversion between HPABA enantiomers was not observed in rats. ( R ) -/ ( S )-HPABA showed higher C max and AUC than those of their prodrugs. However, the values of t 1/2 of prodrugs were higher than those of ( R ) -/ ( S )-HPABA. Furthermore, the higher V z values of prodrugs might improve the targeting of ( R ) -/ ( S )-HPABA in rat tissues.

Graphical Abstract Unlabelled image, A rapid, simple and sensitive ultra-high performance liquid chromatography–tandem mass spectrometric (UPLC–MS/MS) method was developed and validated for the determination of hederasaponin B, an active triterpenoid saponin widely existed in Hedera helix L. Plasma samples were processed by protein precipitation with acetonitrile and separated on a Thermo Hypersil GOLD C18 (2.1 mm × 50 mm,1.9 µm) at flow rate of 0.3 ml/min, with a gradient elution consisting of acetonitrile and water containing 0.1% (v/v) formic acid at 30 °C and detected by electrospray ionization mass spectrometry in the positive multiple reaction monitoring (MRM) mode. The linearity was found to be within the concentration range of 0.5–5000 ng/ml with a lower limit of quantification of 0.5 ng/ml. The absolute oral bioavailability of hederasaponin B was 0.24 ± 0.49%. This indicated that the concentration-time course of the hederasaponin B existed a double-peak phenomenon. This method was further applied to the determination of hederasaponin B in rat plasma and showed good practicability, for the first time, after intragastric (25 mg/kg) and intravenous (2 mg/kg) administration in rats.