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In this work, a new quantitative analysis method of multi-components analysis via a single marker strategy coupled with high-performance liquid chromatography (HPLC) analysis, was proposed to analyze nine nucleosides (cytidine, uridine, 2'-deoxyuridine, inosine, guanosine, 2'-deoxyguanosine, thymidine, adenosine, and 2'-deoxyadenosine) as quality control markers in Rhizoma Paridis. Guanosine was set as the internal reference substance, whose content in Rhizoma Paridis was determined using conventional external standard method. Then, relative correction factors between guanosine and the other eight nucleosides were measured respectively. The amounts of the other eight components were calculated according to the relative correction factors by the quantitative analysis of multi-components via a single marker method. Finally, the result of vector angle cosine analysis showed that there was no significant difference of the contents between the external standard method and the quantitative analysis of multi-components via a single marker method, indicating that the quantitative analysis of multi-components via a single marker method can be applied for the quality control of Rhizoma Paridis. As far as we know, this is also the first report to analyze nucleosides by the quantitative analysis of multi-components via a single marker method, providing an efficient and promising quality assessment method for other traditional Chinese medicine containing nucleosides.

Three new diterpenoids, euphstrachenols A–C (1, 2, and 11), together with nineteen known analogues were isolated from the roots of Euphorbia stracheyi. Compounds 1 and 2 were lathyrane-type diterpenoids with a decadienoyl acidic moiety. Compound 11 was an ingenane-type diterpenoid with a deca-2′′E,4′′E,6′′E-trien-1-one moiety. Their structures were elucidated by comprehensive spectroscopic analyses. All the isolated compounds were evaluated in vitro for their cytotoxic activity against four human cancer cell lines and a murine cell line, and compounds 1, 2, 4, 5, 7, 9, and 11–14 exhibited moderate cytotoxicity against MV4-11 cell line with IC50 values from 3.48 to 30.02 μM.

Phytopathogenic fungi have been considered as being an enormous threat in the agricultural system. In our search of new antifungal natural products, nine new halogenated cyclopentenones, bicolorins A-I (1-3, and 5-10), along with three known cyclopentenones (4, 11, and 12) were isolated from the endophytic fungus Saccharicola bicolor of Bergenia purpurascens by the one strain-many compounds strategy. Their structures and absolute configurations were elucidated based on extensive spectroscopic analysis, X-ray crystallographic analysis, and time-dependent density functional theory-equivalent circulating density calculations. Compounds 1-12 showed antifungal activities against five phytopathogenic fungi (Uromyces viciae-fabae, Pythium dissimile, Gibberella zeae, Aspergillus niger, and Sclerotinia sclerotiorum). Especially, bicolorins B and D (2 and 5) exhibited strong antifungal activities against P. dissimile with the MIC values of 6.2 and 8.5 μg/mL, respectively, compared with the positive control cycloheximide (MIC of 8.6 μg/mL). Additionally, bicolorin D was proven to be potently antifungal against S. sclerotiorum in vitro and in vivo. This work provides an effective strategy for searching antifungal candidate agents.

Background Astragalosidic acid (LS-102) is a new water-soluble derivative of astragaloside IV - a major effective component isolated from the Chinese herb Astragali Radix. Our previous study showed that LS-102 exhibited potent cardiovascular activity. Purpose The objective of this study was to investigate the pharmacokinetic properties of LS-102 after single-dose, oral administration in beagle dogs by developing and validating an ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) method. Method and result The chromatographic separation was performed on a Acquity HSS C18 column (100 mm × 2.1 mm, 1.8 µm) by a gradient elution using a mobile phase consisting of water and acetonitrile at a flow rate of 0.35 ml/min. The analytes were detected with a triple quadrupole tandem mass spectrometry in multiple reaction monitoring mode. Method validation revealed a wide linearity over the range of 2.0–10,000 ng/ml together with satisfactory intra- and inter-day precision, accuracy, and recovery. Stability testing showed that LS-102 spiked into dog plasma was stable for 4 h at room temperature, for up to 2 weeks at −80 °C, and during three freeze-thaw cycles. The method was effectively and successfully applied to the pharmacokinetics of LS-102 after oral administration (5, 10 and 20 mg/kg) to beagle dogs. Peak plasma concentrations are attained within approximately 2 h after oral administration with a half-life ranging from 1.55 h to 4.49 h. The plasma concentration-time curve of LS-102 after oral administration presents the phenomenon of a double-peak absorption phase. The peak concentration and area under the concentration-time curve of LS-102 seemed to increase with the increasing doses proportionally, that suggesting linear pharmacokinetics in dogs. Meanwhile, the doxorubicin (Dox)-injured H9c2 cell model was prepared by incubating the cells in 1 µM Dox for 24 h. MTT assay and LDH release measurement showed that LS-102 protected against Dox-induced cardiomyocyte death. Conclusion The obtained results may help to guide the further pre-clinical research of LS-102 as a potentially novel cardioprotective agent.

Twenty-two new sesquiterpenoids with four skeletal types and 15 known analogues were isolated from the whole plants of Ligularia rumicifolia. The structures of the isolates were elucidated based on comprehensive spectroscopic data analysis. Compound 1 is a C

Five previously undescribed compounds, including two dendrobine-type alkaloids (1 and 2), three bibenzyl derivatives (3–5), along with six known compounds were isolated from orchids Dendrobium findlayanum. The structures and absolute configurations of the undescribed compounds were elucidated on the basis of HR-ESIMS, NMR spectroscopy, optical rotation value, as well as electronic circular dichroism (ECD) calculations. The cytotoxic effects of the isolated compounds on three human tumour cell lines (A172, SHSY5Y, and Hela) were evaluated by the MTT assay. Compound 6 showed excellent inhibitory activities against three human tumour cell lines with IC50 ranging from 1.65 μM to 3.77 μM. All these compounds were assessed for their activity of promoting the gastrointestinal motility of zebrafish treated with Nile red. Compound 6 have excellent activity to promote the gastrointestinal motility of zebrafish at the concentration of 0.3 μM.

Phytopathogenic fungi have been considered as being an enormous threat in the agricultural system. In our search of new antifungal natural products, nine new halogenated cyclopentenones, bicolorins A-I (

A quantitative method using ultra-performance liquid chromatography coupled with tandem mass spectrometry (UPLC-MS/MS) was developed for the determination of 60 compounds, belonging to a variety of veterinary drug (VD) classes, in meat. The included analytes belong to the following VD classes: β-agonists, sulfanilamides, quinolones, macrolides, tetracyclines, β-lactams, nitroimidazoles, glucocorticoids, sex hormones, chloromycetins, sedatives, and olaquindox metabolite. The effective PRiME pass-through cleanup procedure was used to ensure high extraction efficiency and good sample cleanup after a simple liquid extraction of the meat samples with acetonitrile/water. The developed method was validated successfully. Mean recoveries for all analytes ranged from 80 to 116%, with the relative standard deviations (RSDs) ≤ 7.8%. Limits of quantification were in the range 0.05–3.0 μg kg−1 and limits of detection were in the range 0.1–10 μg kg−1. The matrix effect was evaluated for the different meat matrices and was found to be markedly different in different matrices. The validated method was used in a pilot study to analyze real samples of pork, beef, mutton, chicken, and pork liver, lambs’ liver, and chicken liver. Trace amounts of β-agonists, oxytetracycline, quinolones, chloromycetin sulfadimidine, and 3-methyl-quinoxaline-2-carboxylicacid were detected in these samples. In conclusion, this workflow can provide a simpler and more cost-effective alternative to conventional analytical methods and is compatible with processing large sample numbers in a short time period.

Guided by the UPLC-ESIMS profile, seven previously undescribed halogenated dihydroisocoumarins, palmaerones A-G, along with eleven known dihydroisocoumarins, were isolated from Lachnum palmae, an endophytic fungus from Przewalskia tangutica by exposure to a histone deacetylase inhibitor SAHA. Structures of the isolates were elucidated by analysis of their NMR, MS and optical rotation values. The antimicrobial, anti-inflammatory and cytotoxic activities of palmaerones A-G were evaluated. Palmaerones A-G showed antimicrobial activities against the strains (C. neoformans, Penicillium sp., C. albicans, B. subtilis and S. aureus), and palmaerone E exhibited potential antimicrobial activities against all the test strains with the MIC value in the range of 10–55 μg/mL. Palmaerones A and E exhibited moderate inhibitory effects on NO production in LPS-induced RAW 264.7 cells, with the IC50 values of 26.3 and 38.7 μM, respectively and no obvious toxicities were observed at 50 μM. Palmaerone E showed weak cytotoxicity against HepG2 with the IC50 value of 42.8 μM. This work provides an effective strategy for expanding natural product resource.

Electrospray ionization mass spectrometry (ESI-MS) technique has limitations in analysis of compounds that are dissolved in nonpolar solvents. In this study, ambient ionization of compounds in solvents that are not "friendly" to electrospray ionization, such as n-hexane, is achieved by conductive nanomaterials spray ionization (CNMSI) on nanomaterial emitters, including carbon nanotubes paper and mesodendritic silver covered metal, which applies high voltages to emitters made of these materials without the assistance of polar solvents. Although the time intensity curves (TIC) commonly vary from 4.5% to 23.7% over analyses, protonated molecular ions were found to be the most abundant species, demonstrating good reproducibility of the technique in terms of ionized species. Higher mass spectrometric responses are observed in analyzing nonpolar systems than polar systems. 2-Methoxyacetophenone, 4-methylacetophenone, benzothiazole, quinolone, and cycloheptanone as low as 2 pg in n-hexane can be directly detected using the developed method. The developed technique expands the analysis capability of ESI-MS for direct, online analysis of nonpolar systems, such as low polarity extracts, normal phase liquid chromatography eluates, and synthetic mixtures. Graphical Abstract.

A kind of metal-organic framework made from γ-cyclodextrin (γ-CD) and potassium ions were explored as excellent formaldehyde (HCHO) absorbents. The adsorption capacity and speed of γ-CD-MOF-K are both about 9 times higher than those of activated carbon, which are attributed to the porous structure and synergistic effect of hydrogen bonding and host-guest interactions.

Tandem mass spectrometry (MS/MS) plays an important role in the screening and structural characterization of natural products. In addition to general fragmentations, chemicals sharing a same particular structure often produce a common characteristic fragmentation pattern under MS/MS experiments which represent a specific characteristic substructure. Therefore, the class of unknown natural products can be predicted by the diagnostic fragment ions based on MS/MS. The peripheral groups of the chemicals within a class could be inferred by general fragmentation pattern. Based on above mentioned concepts, SmartMass, a software program was developed and implemented for intelligent interpretation of natural products.

A simple, fast, and highly sensitive direct competitive enzyme-linked immunosorbent assay (ELISA) based on bovine serum albumin (BSA) antigen labeled amine-terminated silicon dioxide (SiO2–NH–BSA) nanoparticles was developed to determine residual BSA in vaccines. As nano-ELISA using nanomaterials with a very high surface-to-volume ratio has emerged as a promising strategy, SiO2–NH–BSA nanoparticles were prepared in this study by the coupling of BSA to SiO2 nanoparticles modified with amidogen, followed by the quantification of BSA via a direct competitive binding of BSA-antigen-labeled SiO2 nanoparticles to anti-BSA antibody conjugated with horseradish peroxidase. The validation study showed that the linear range of this method was from 1 to 90 ng/mL (r = 0.998) and the limit of detection was 0.67 ng/mL. The intra-assay and interassay coefficients of variation were less than 10% at three concentrations (10, 40, and 70 ng/mL), and the recovery was 92.4%, indicating good specificity. As a proof of principle, this new method was applied in the analysis of residual BSA in five different vaccines. Bland–Altman plots revealed that there was no significant difference in the accuracy and precision between our new method and the most commonly used sandwich ELISA. From the results taken together, the new method developed in this study is more sensitive and facile with lower cost and thus demonstrated potential to be applied in the quality control of biological products.

Three new chlorinated phenolic glycosides, namely przewatangosides A-C (1-3), along with one known compound, globosumoside A (4), were isolated from the whole plants of Przewalskia tangutica. Their structures were unequivocally determined by extensive spectroscopic analysis and chemical method. The cytotoxic activities of the isolated phenolic glycosides (1-4) were evaluated against the five human cancer cell lines A549, MCF-7, SMMC-7721, HepG2 and HL-60. Przewatangoside A (1) exhibited weak cytotoxicity against SMMC-7721 with the IC50 value of 38.1 μM. All the tested compounds were inactive (IC50 > 50 μM) to the normal human hepatocyte cell line (L02).

A new triterpenoid derivative, 2,3-seco-bauer-8-en-2,3-dioic acid (1), a new natural product, 3α-hydroxyolean-13(18)-en-24-oic acid (2), along with 19 known compounds (3–21), were isolated from the methanol extract of the aerial parts of Schnabelia oligophylla. The chemical structures were established by means of spectroscopic analysis including one- and two-dimensional NMR spectroscopy and comparison with previously reported data.

The application domains of classic enzyme-linked ligand binding assay (ELBA) is relatively narrow due to the high cost and hardly available binding receptor. In here, we described for the first time the possibility of developing a new ELBA based on silica nanoparticles (nano-SiO2) to assess the ibuprofen in human urine. Nano-SiO2 with a large surface area was introduced as stationary phase to improve the analytical performance. In the experiment, a competitively binding procedure with human serum albumin (HSA) was performed between the ibuprofen presented in sample and horseradish peroxidase labeled ibuprofen (HRP-ibuprofen) subsequently added. After centrifugal separation, the HRP/ibuprofen/nano-SiO2 composite catalyzed the substrate solution (TMB/H2O2) with a color change from colorless to yellow for quantitative measurement via an ultraviolet spectrophotometer. As a validation of the new principle, the developed nano-ELBA method was applied in the determination of ibuprofen excreted in human urine with excellent performance. This detection range only depends on the solubility of ligand and sensitivity of UV spectrophotometer. Our results indicate that this new method demonstrated to be able to rapidly and adequately determine the concentration of components in biological samples and advocate its effectiveness for various applications.

Three new labdane diterpenes, namely loxocalyxin D (1), loxocalyxin E (2) and 13-epiloxocalyxin E (3), were isolated from the whole plants of Loxocalyx urticifolius Hemsl. Their structures were elucidated by extensive spectral analysis and chemical methods. The absolute configuration of loxocalyxin D (1) was confirmed by X-ray crystallographic analysis. The cytotoxic activities of the isolated labdane diterpenes were evaluated against the four human cancer cell lines A549, HepG2, HL-60 and MCF-7. 13-epiloxocalyxin E (3) exhibited selective cytotoxicity against A549 and MCF-7 with the IC50 values of 22.4 and 47.3 μM, respectively.

A pH and glutathione (GSH) dual bio-relevant triggered supramolecular system is constructed through the non-covalent host–guest interactions between the adamantane (ADA) on camptothecin (CPT) and β-cyclodextrin (β-CD) on the side chain of the backbone of hyaluronic acid (HA). The obtained non-covalent supramolecular β-CD-g-OX-HA/ADA-CPT complex could further self-assemble into a stable uniform sphere micellar structure with constant drug loading content in the extracellular environment but is cleaved in the cytosol of the cancer cells due to the acidic environment and the presence of a high concentration of GSH, resulting in a synergistic-fast pH and GSH triggered drug releasing behavior. The cytotoxicity of the supramolecular β-CD-g-OX-HA/ADA-CPT micelles was investigated using Hep G2 cancer cells by MTT assays, which displayed that supramolecular β-CD-g-OX-HA/ADA-CPT micelles had exhibited enhanced cellular proliferation inhibition against Hep G2 cancer cells compared to the free CPT, while the β-CD-g-OX-HA had good cell compatibility. In vivo studies of the β-CD-g-OX-HA/ADA-CPT micelles showed a higher in vivo efficacy without side effects and also confirmed the compatibility of the β-CD-g-OX-HA. It is anticipated that this supramolecular complex will give the possibility to fabricate new types of bio-relevant triggered nanocarriers for cancer therapy.

A new type of chiral magnetic nano-particles was prepared via covalently linked magnetic nano-particles (Fe3O4) and heptakis (6-O-triisopropylsilyl)-β-cyclodextrin (6-TIPS-β-CD). The resulting selectors (TIPS-β-CD-MNPs) combined the high magnetic property Fe3O4 and efficient chiral recognition ability of 6-TIPS-β-CD. The enantioselectivity of TIPS-β-CD-MNPs towards 1-(1-naphthyl) ethylamine was six times higher than that of parent β-CD modified Fe3O4 particles.

The abusive use of 2,4-dichlorophenoxyacetic acid (2,4-D) was very common in the commercial production of bean sprouts. Herein, a simple and highly sensitive nano-SiO2-based ELISA method for residual 2,4-D detection was developed. The test depends on the direct competitive combination to anti-2,4-D antibody labeled by horseradish peroxidase (HRP) between nano-SiO2 immobilized by ovalbumin-2,4-D (SiO2-OVA-2,4-D) and free 2,4-D in sample. The linear range of this method was from 1 to 350 ng/mL (r = 0.997), and the limit of detection (LOD) was 0.079 ng/mL. The coefficient variations of intra-day and inter-day were all lower than 10% at three concentrations (20, 150, and 250 ng/mL). The mean recovery was 93.2%, and the specificity was satisfactory. The results indicated that the method could be useful for fast determination of residual 2,4-D in bean sprout samples using classic TMP/HRP system and a conventional UV spectrophotometer.

Eight previously undescribed oleanane-type triterpenoid saponins, clematangoticosides A-H, together with eight known saponins, were isolated from the whole plants of Clematis tangutica (Maxim.) Korsh. Their structures were elucidated by extensive spectroscopic analysis, in combination with chemical methods (acid hydrolysis and mild alkaline hydrolysis). Clematangoticosides D-G were found to be unusual 23, 28-bidesmosidic glycosides. The cytotoxic activities of all of the isolated saponins were evaluated against the four human cancer cell lines SGC-7901, HepG2, HL-60 and U251MG. Clematoside S, sapindoside B, kalopanax saponin A, and koelreuteria saponin A exhibited cytotoxicity against all of the test cancer cell lines with IC50 values in the range of 1.88-27.20 μM, while clematangoticoside D and F showed selective cytotoxicity against SGC-7901 with IC50 values of 24.22 and 21.35 μM, respectively.

Phytochemical investigation into the bark of Tsuga longibracteata led to the isolation of three lignans (1–3), two triterpenoids (4, 5), nine flavonoids (6−14), three sterols (15–17) and five phenolic acids (18–22). Their structures were determined by spectroscopic analysis of their spectral data with those reported in literature. Among them, compounds 1–3, 6–22 were obtained from this species for the first time. The chemotaxonomic significance of the isolated compounds is discussed.

We have developed a new competitive protein binding assay (CPBA) based on human serum albumin functionalized silicon dioxide nanoparticles (nano-SiO2-HSA) that can be used for naproxen determination in urine. Compared with a conventional multi-well reaction plate, nano-SiO2 with a high surface-area-to-volume ratio could be introduced as a stationary phase, markedly improving the analytical performance. Nano-SiO2-HSA and horseradish peroxidase-labeled-naproxen (HRP-naproxen) were prepared for the present CPBA method. In this study, a direct competitive binding to nano-SiO2-HSAwas performed between the free naproxen in the sample and HRP-naproxen. Thus, the catalytic color reactions were investigated on an HRP/3,3&prime, 5,5&prime, tetramethylbenzidine (TMB)/H2O2 system by the HRP-naproxen/nano-SiO2-HSA composite for quantitative measurement via an ultraviolet spectrophotometer. A series of validation experiments indicated that our proposed methods can be applied satisfactorily to the determination of naproxen in urine samples. As a proof of principle, the newly developed nano-CPBA method for the quantification of naproxen in urine can be expected to have the advantages of low costs, fast speed, high accuracy, and relatively simple instrument requirements. Our method could be capable of expanding the analytical applications of nanomaterials and of determining other small-molecule compounds from various biological samples.

A new dibenzocyclooctdiene (

Astragaloside IV (AGS IV) is the most important bioactive constituent of Radix Astragali. However, its disappointing clinical application is mainly caused by its very low solubility in biologic fluids, resulting in poor bioavailability after oral administration. We recently obtained a novel water-soluble derivative of AGS IV (astragalosidic acid, LS-102) that displayed significant cardioprotective potential against hypoxia-induced injury. The objective of this study was to investigate the intestinal absorption, main pharmacokinetic parameters and acute toxicity of LS-102 in rodents compared with AGS IV. An oral dose of LS-102 and AGS IV (20 mg/kg) was administered to Sprague-Dawley (SD) rats, and blood samples were collected at predetermined time points. The plasma concentrations were detected by a validated UHPLC-MS/MS method, and pharmacokinetic parameters were calculated using a compartmental model. In the intestinal permeability study, the transport of LS-102 across Caco-2 cell monolayers was investigated at six concentrations from 6.25 to 250 µM. Moreover, the acute toxicity of LS-102 (40–5000 mg/kg) via a single oral administration was investigated in BALB/c mice. LS-102 was rapidly absorbed, attaining a maximum concentration of 248.7 ± 22.0 ng/ml at 1.0 ± 0.5 h after oral administration. The relative bioavailability of LS-102 was twice that of AGS IV. LS-102 had a Papp (mean) of 15.72–25.50 × 10−6 cm/s, which was almost 500-fold higher than that of AGS IV, showing that LS-102 had better transepithelial permeability and could be better absorbed in the intestinal tract. The acute toxicity study showed no abnormal changes or mortality in mice treated with LS-102 even at the single high dose of 5000 mg/kg body weight. Oral LS-102 produced a pharmacokinetic profile different from AGS IV with higher bioavailability, while the toxic tolerance was similar to previous estimates. Thus, we speculated that LS-102 might provide better clinical efficacy and be a potential candidate for the new drug development of Radix Astragali.

Airborne particulate matter (PM) pollution has become a serious environmental problem. Thus, there is a need for the development of air filters with satisfactory overall performance. In this paper, we develop a kind of β-cyclodextrin (β-CD) based air filter with high strength, which has not only high filtration efficiency (about 99%) but also good air permeability (the pressure drop is only 45Pa). Especially after long-term application, the pression drop of β-cyclodextrin based was less than half of the commercial air-filter. Additionally, the material can capture the toxic gasous chemicals (e.g. formaldehyde and SO2). The introduction of β-CD is supposed to be the key factor for improvement of air filter.

The catechins in oolong tea are related to its flavor and health benefits. In this paper, a new strategy for a quantitative analysis of multi-components via a single marker (QAMS) was developed and validated to analyze six catechins (epigallocatechin, catechin, epicatechin, epigallocatechin gallate, gallocatechin gallate, and epicatechin gallate) in oolong tea by HPLC. Catechin was chosen as the internal reference substance. The relative correction factors (RCFs) between catechin and the other five catechins were investigated for the QAMS calculation using five different types of chromatographic columns. Meanwhile, the content of each of the six analytes was also determined by a conventional external standard method. Finally, the angle cosine value revealed that there was no significant difference between the QAMS method and the external standard method. The QAMS method established in this study solved the problem of the availability and high cost of some standard substances and would be useful for providing an efficient and feasible quality assessment method for oolong tea and other botanic samples.

Three novel oxazoline alkaloids, 1-oxa-3-azaspiro [4.5] dec-2-ene-8-one (1), 1-oxa-3-azaspiro [4.5] dec-2, 6-diene-8-one (2), and 1-oxa-3-azaspiro [4.5] dec-10-methoxy-2, 6-diene-8-one (3) were isolated from the methanol extract of the whole plant of Gymnotheca chinensis. The chemical structures were established by means of spectroscopic analysis including one- and two-dimensional NMR spectroscopy.

Four rare polycyclic spiro lignans (1-4) and four new biphenyl tetrahydrofuranone lignans (5-8) were isolated from the whole plant of Gymnotheca involucrata. The structures of the new compounds were elucidated on the basis of detailed spectroscopic analysis and the absolute configuration of 1 was confirmed by single crystal X-ray diffraction. Bioassay results showed that compounds 2 and 6 exhibited weak antifungal activity against Uromyces viciae-fabae at 100 ppm in leaf-disc assays, while compound 3 demonstrated moderate insecticidal activity against Diabrotica balteata at 500 ppm in an artificial diet assay.

Two diketopiperazine derivatives, altenarizines A ( 1 ) and B ( 2 ), and a new glucosyl sesterterpene, 24-α- d -glucosyl-(−)-terpestacin ( 3 ), together with two known phytotoxic sesterterpenes, (−)-terpestacin ( 4 ) and fusaproliferin ( 5 ), were isolated from the fermentation broth of an endophytic fungus Alternaria alternata , which was obtained from the fresh root of Ceratostigma griffithii . Structures of all the isolates were identified by spectroscopic data.

A novel magnetic nanocomposite (MNPs@DNA) was synthesized by bonding double strand DNA (ds-DNA) onto Fe3O4 magnetic nanoparticles (MNPs) directly. MNPs@DNA was characterized by cyclic voltammetry (CV), differential pulse voltammetry (DPV), Fourier transform infrared spectroscopy (FT-IR) and thermo-gravimetric analysis (TGA), which indicated that ds-DNA was immobilized onto MNPs. Vibrating sample magnetometer (VSM) analysis indicated that the MNPs@DNA had a high saturation magnetization of 42.97emu/g. A novel method for screening of active compounds from natural sources was developed by employing MNPs@DNA as a nanobait and high-performance liquid chromatography-mass spectrometry as detecting system. Columbamine, palmatine, jateorhizine, epiberberine and berberine were identified as DNA binders from the extract of Rhizoma coptidis. In addition, a comparison of the binding abilities among MNPs with different DNA strand lengths (25, 200 and 1200bp) showed that the shortest one exhibited the highest binding ability. This is the first report on fast chemical characterization of active ingredients in medicinal plant using ds-DNA immobilized on magnetic nano-baits. This method can be used not only for screening of DNA binders from complex herbal matrices, but also for assessing the affinities between a specific ds-DNA and its potential binders.

Two new biphenyl butyl neolignan derivatives, named gymnothebutyllignans A (1) and B (2), were isolated from the whole parts of endemic medicinal plant of Gymnotheca involucrata (Saururaceae). The structures of the new compounds were elucidated by extensive NMR and MS data, and the absolutely configuration of compound 1 was confirmed by X-ray crystal diffraction analysis.

A new strategy for the hapten design of natural glycoside and application for the preparation of antibody is reported in this work. With astragaloside IV (AGS-IV) as an example, C6”-CH2OH on a glucosyl group was selectively oxidized by 2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPO) oxidation to C6”-COOH, which was subsequently condensed with -NH2 on bovine serum albumin to get artificial antigen. Then, the successful preparation of artificial antigen was verified by TCL, SDS-PAGE, UV, and MALDI-TOF-MS. Finally, rabbits were immunized with artificial antigen to obtain an antibody against AGS-IV. After tests of the titer, IC50, and cross-reactivity, the results showed that the antibody prepared by TEMPO oxidation in this work had higher specificity than that the antibody prepared by conventional sodium periodate (NaIO4) oxidation. The hapten, as a carboxylic acid derivative of AGS-IV, has better water solubility than AGS IV, which is more suitable for the synthesis of the hapten-carrier protein conjugate in aqueous phase, achieving another virtue of TEMPO oxidation over NaIO4 oxidation. This new strategy provides new ideas for the design of haptens of other natural glycosides, as well as the preparation of their antibodies.

A new benzocycloheptanone derivative, named gymnothedelignan C, and 14 known compounds were isolated from the Chinese endemic genus plant Gymnotheca chinensis Decne. The structure of the new compound was established by 1D and 2D NMR experiments.

To study the chemical constituents of n-butanol extract in the broth of Myrothecium verrucaria.The chemical constituents were isolated,purified and identified by various chromatographic and spectral techniques.14 compounds were isolated and identified from n-butanol extracts of Myrothecium verrucaria broth. They were identified as cyclo-( Pro-Phe)( 1),cyclo-( 4-OH-Pro-Phe)( 2),cyclo-( 4-OH-Pro-Leu)( 3),cyclo-( Ala-Pro)( 4),cyclo-( 4-methyl-Pro-9-propyl-Gly)( 5),cyclo-( Pro-Gly)( 6),cyclo-( Phe-Gly)( 7),cyclo-( Leu-Leu)( 8),N-acetyl tryptamine( 9),N-( 2-phenylethyl) acetamide( 10),N-( 2-hydroxyphenethyl) acetamide( 11),N-( 4-hydroxyphenethyl) acetamide( 12),uracil( 13) and thymine( 14).Compounds 1 ~ 14 are obtained from the strain Myrothecium verrucaria for the first time.

Although herb medicines have become the major source for new drug discovery, many of them are largely under-explored due to the purity-activity relationship. Efficient identification of bioactive compounds in conventional stepwise separation and isolation has not yet been elucidated. Therefore, we proposed a new separation strategy for holism understanding of herb pharmacology using molecularly imprinted polymers (MIPs). Astragali Radix (AR), important in traditional Chinese medicine, was chosen in this study for multicomponent knockout followed by bioactivity evaluation. We prepared calycosin molecularly imprinted polymers (calycosin-MIPs) which could selectively recognize flavonoid aglycons in AR. The molecular selectivity of calycosin-MIPs as a critical parameter was evaluated using the template and other high content compounds in AR. Based on it, using the calycosin-MIPs material via solid-phase extraction procedures was applied for the knockout of flavonoid aglycons in AR. Finally, hypoxia/reoxygenation model in H9c2 cells was used to evaluate the activity of the AR extract before and after knockout. The results showed that calycosin-MIPs as recognition materials for flavonoid aglycons in AR are applied in one-step separation with high selectivity and tunability. The subextract in the absence of flavonoid aglycons has been demonstrated to clarify the cardio-protective components of AR. In conclusion, this proof-of-principle study is the first one showing that molecular imprinting technology coupled with a bioassay can be used to explore the bioactive variability from the perspective of multicomponent separation of herbal medicine.

A new dibenzocyclooctdiene (1), and a new eupodienone (2) type lignans were isolated along with five known analogues from the whole plant of Gymnotheca involucrata Pei. The structures of the new compounds were elucidated on the basis of detailed spectroscopic analysis. Bioassay results showed that compounds 1 and 2 exhibited no antimicrobial activity against four Gram-positive bacterial strains and four Gram-negative bacteria at the concentration of 1 mg/mL.

Healable, electrically conductive materials are highly desirable and valuable for the development of various modern electronics. But the preparation of a material combining good mechanical elasticity, functional properties, and intrinsic self-healing ability remains a great challenge. Here, we design composites by connecting a polymer network and single-walled carbon nanotubes (SWCNTs) through host-guest interactions. The resulting materials show bulk electrical conductivity, proximity sensitivity, humidity sensitivity and are able to self-heal without external stimulus under ambient conditions rapidly. Furthermore, they also possess elasticity comparable to commercial rubbers.

Two end-decorated homopolymers, methoxy polyethylene glycol-ferrocene (mPEG-Fc) and poly(N-isopropylacrylamide)-β-cyclodextrin (PNIPAM-β-CD), were further orthogonally self-assembled into stable micelles in aqueous solution by controlling the temperature of the solution via terminal host–guest interactions. Because of the H2O2 cleavable CD/Fc connection and thermoresponsive PNIPAM, an H2O2 and thermo dual-controlled drug release based on this system was also achieved. Interestingly, the cytotoxicity evaluation of mPEG-Fc/PNIPAM-β-CD indicated good biocompatibility. Compared with free doxorubicin, the doxorubicin-loaded supramolecular micelles exhibited equal cellular proliferation inhibition toward A549 cells. This supramolecular complex is thus anticipated to serve as a promising new type of alternative drug-delivery system.

Highly active and recoverable nanobioreactors prepared by immobilizing rat liver microsomes on magnetic nanoparticles (LMMNPs) were utilized in metabolic study of Angelica dahurica extracts. Five metabolites were detected in the incubation solution of the extracts and LMMNPs, which were identified by means of HPLC-MS as trans-imperatorin hydroxylate (M1), cis-imperatorin hydroxylate (M2), imperatorin epoxide (M3), trans-isoimperatorin hydroxylate (M1') and cis-isoimperatorin hydroxylate (speculated M2'). Compared with the metabolisms of imperatorin and isoimperatorin, it was found that the five metabolites were all transformed from these two major compounds present in the plant. Since no study on isoimperatorin metabolism by liver microsomal enzyme system has been reported so far, its metabolites (M1' and M3') were isolated by preparative HPLC for structure elucidation by (1) H-NMR and MS(2) analysis. M3' was identified as isoimperatorin epoxide, which is a new compound as far as its chemical structure is concerned. However, interestingly, M3' was not detected in the metabolism of the whole plant extract. In addition, a study with known chemical inhibitors on individual isozymes of the microsomal enzyme family revealed that CYP1A2 is involved in metabolisms of both isoimperatorin and imperatorin, and CYP3A4 only in that of isoimperatorin.

This study reported a smart, easy to apply, flexible and green strategy for obtaining a biomimic micro-nanostructures. 1-Mercapto-12-( p -nitrophenoxy) dodecane (MPND) and n -dodecanethiol were used to form low surface energy film on a silver mesodendritic structure coated zinc substrate. Scanning electron microscope (SEM) and X-ray photoelectron spectroscopy (XPS) were used to characterize surface morphology and mesocrystal structures. Noncovalently linked sodium nonanoyloxy benzene sulfonate (NOBS) was used to form “lipid-like bilayers” on the surface, making it possible for the surface to switch its surface wettability reversibly. The water contact angle (CA) on the constructed surface varies from 168 ± 2° (before processed by NOBS) to 55 ± 2° (after processed by NOBS). This phenomenon can be explained by the formation and disruption of “lipid-like bilayers” to affect the wettability of the surface. This work is of great scientific interests and may provide insights into the design of novel functional devices that are relevant to surface wettability, such as microfluidic devices and sensors.

Self-assembly of stimuli-responsive polymeric nanoparticles have attracted great attention in recent years due to their prospective biological applications. This paper developed a novel pH-sensitive amphiphilic dendritic polyrotaxane drug-polymer conjugate by covalently linking doxorubicin (DOX) and dendritic polyrotaxane via a pH-responsible hydrazone bond with 1.84 wt% (weight percent) of DOX. The drug-polymer conjugate was amphiphilic and could be self-assembled to micelles (PR-g-DOX micelles) in an aqueous solution. The globular morphology and compact micelles with a diameter of around 110 nm were observed by SEM and TEM. Moreover, the micelles showed a significantly faster DOX release at mildly acidic pH of 6.0 and 5.0 and almost no burst release at the physiological pH of 7.4. Notably, it was confirmed that this micelle could efficiently deliver DOX to the nuclei of the tumor cells, which led to a much greater cytotoxic effects in the A549 cancer cells than the parent DOX. In vivo results revealed better drug tolerability of PR-g-DOX micelles and a higher in vivo efficacy without any increase in the toxicity of the PR-g-DOX micelles. Furthermore, the maximum tolerated dose (MTD) results showed that PR-g-DOX micelles showed an excellent safety profile with a two-fold higher MTD (10 mg kg−1 DOX) than that of free DOX (5 mg kg−1 DOX). We are convinced that the PR-g-DOX micelle has tremendous potentials for targeted cancer therapy.