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Saussurea involucrata has been reported to have potential therapeutic effects against myocardial ischemia. The pharmacological effects of oral natural medicines may be influenced by the participation of gut microbiota. In this study, we aimed to investigate the bidirectional regulation of gut microbiota and the main components of Saussurea involucrata. We first established a quantitative method for the four main components (chlorogenic acid, syringin, acanthoside B, rutin) which were chosen by fingerprint using liquid chromatography tandem mass spectrometry (LC-MS/MS), and found that gut microbiota has a strong metabolic effect on them. Meanwhile, we identified five major rat gut microbiota metabolites (M1–M5) using liquid chromatography tandem time-of-flight mass spectrometry (LC/MSn-IT-TOF). The metabolic properties of metabolites in vitro were preliminarily elucidated by LC-MS/MS for the first time. These five metabolites of Saussurea involucrata may all have potential contributions to the treatment of myocardial ischemia. Furthermore, the four main components (10 μg/mL) can significantly stimulate intestinal bacteria to produce short chain fatty acids in vitro, respectively, which can further contribute to the effect in myocardial ischemia. In this study, the therapeutic effect against myocardial ischemia of Saussurea involucrata was first reported to be related to the intestinal flora, which can be useful in understanding the effective substances of Saussurea involucrata.

Defect-mediated Z-scheme BiO2-x/Bi2O2.75 heterojunction photocatalysts without electron mediator was prepared via a simple low-temperature hydrothermal method. DFT proved that the existence of oxygen vacancies would affect the geometric and electronic structure of BiO2-x and Bi2O2.75, which played an indispensable role in promoting exciton dissociation. BiO2-x/Bi2O2.75 exhibited a higher redox ability compared with the pure BiO2-x due to the Z-scheme photocatalytic mechanism, which could be ascribed to the formation of the build-in electric field induced by Bi and O defects. The as-synthesized photocatalysts exhibited excellent photocatalytic activity over the full solar spectrum from UV to NIR light due to the LSPR effect of oxygen vacancies, indicating its effective utilization of solar energy. The degradation rates of RhB over the optimal BiO2-x/Bi2O2.75 were 8.49, 10.22 and 3.24 times higher than that of the pure BiO2-x under visible light, simulated sunlight and NIR light irradiation, respectively. The excellent photocatalytic activity was ascribed to the synergistic effects of the LSPR effect of oxygen vacancies and the Z-scheme interfacial heterojunction. It was believed that this work provided a new idea to design high active and full solar spectrum-driven photocatalysts for energy conversion and environmental remediation.

Catalytic removal of NO by CO has been studied over a series of LaNi0.5M0.5O3 (M = Co, Mn, Cu) perovskite oxide catalysts were synthetized via an improved sol–gel method. The effects of M-doped on physicochemical properties of LaNiO3 were systemic characterized by XRD, BET, SEM, ICP-AES, XPS, H2-TPR and O2-TPD techniques. The possible catalytic mechanism for NO + CO model reaction was also tentatively proposed with the help of the in situ DRIFTS technique. The M-doped samples remained pure perovskite structure and exhibited modified activity, among which the LaNi0.5Cu0.5O3 possessed optimized catalytic performance, especially superior N2 selectivity. It is confirmed that the amorphous CuO highly dispersed on Cu-doped defective perovskite oxide, the reduction of Cu2+ to Cu+ is vital for the chemisorption of CO, a large amount of oxygen vacancies accelerated the dissociation of NO and N2O. Hence, adsorbed CO can fast react with N and O at lower temperature, afterwards N2O was converted to N2 fleetly, leading the improvement of activity/selectivity toward NO + CO reaction.

Methamphetamine (METH) is a stimulant drug. METH abuse induces hepatotoxicity, although the mechanisms are not well understood. METH-induced hepatotoxicity was regulated by TLR4-mediated inflammation in BALB/c mice in our previous study. To further investigate the underlying mechanisms, the wild-type (C57BL/6) and Tlr4−/− mice were treated with METH. Transcriptomics of the mouse liver was performed via RNA-sequencing. Histopathological changes, serum levels of metabolic enzymes and lipopolysaccharide (LPS), and expression of TLR4-mediated proinflammatory cytokines were assessed. Compared to the control, METH treatment induced obvious histopathological changes and significantly increased the levels of metabolic enzymes in wild-type mice. Furthermore, inflammatory pathways were enriched in the liver of METH-treated mice, as demonstrated by expression analysis of RNA-sequencing data. Consistently, the expression of TLR4 pathway members was significantly increased by METH treatment. In addition, increased serum LPS levels in METH-treated mice indicated overproduction of LPS and gut microbiota dysbiosis. However, antibiotic pretreatment or silencing Tlr4 significantly decreased METH-induced hepatic injury, serum LPS levels, and inflammation. In addition, the dampening effects of silencing Tlr4 on inflammatory pathways were verified by the enrichment analysis of RNA-sequencing data in METH-treated Tlr4−/− mice compared to METH-treated wild-type mice. Taken together, these findings implied that Tlr4 silencing, comparable to antibiotic pretreatment, effectively alleviated METH-induced hepatotoxicity by inhibiting LPS-TLR4-mediated inflammation in the liver.

A novel fluorine surface modified mesoporous carbon nitride (mpg-C3N4) photocatalysts were synthesized by etching SiO2 with NH4HF2. The mechanism of formation and the factors that affect its photocatalytic activity were investigated. Interestingly, the introduction of F atoms improves the performance of surface state and widens the energy band gap of surface-modified mpg-C3N4 due to the higher separation and efficient mobility of the photoinduced carriers. Consequently, the fluorine-modified mpg-C3N4 exhibits higher carrier lifetime (8.64 ns) than mpg-C3N4 (7.14 ns), which improves the photocatalytic efficiency under ultraviolet light. The enhanced photocatalytic activity was evaluated by studying the degradation experiments of Rhodamine B. It is expected that the present fluorine modification at the surface of mpg-C3N4 may provide new insights in basic research and energy conversion.

Here, we report the first example of the utilization of p-nitro-tetradecyloxy-calix[4]arene (C4A-NO2) as a stationary phase for capillary gas chromatographic (GC) separations. The statically coated C4A-NO2 column exhibited a high column efficiency of 3815 plates per m and moderate polarity. The C4A-NO2 column was investigated for its separation performance and retention behaviours by utilizing a wide variety of isomer mixtures, covering alkylated benzenes and naphthalenes, alkenes, furans, alcohols, benzaldehydes, phenols and halogenated anilines. Importantly, the C4A-NO2 column exhibited high resolving capability for both aliphatic and aromatic isomers. Particularly, it displayed advantageous resolving capability over the commercial DB-17 column for halogenated aniline isomers. This work provides a good reference for designing calixarene derivatives as GC stationary phases, which is important for developing a family of stationary phases with specific selectivity.

A novel strategy to boost the oxygen evolution reaction (OER) activity of NiFe-LDHs has been developed using reduced graphene oxide (rGO) as both the substrate and electronic carrier. Basically, a GO hydrogel is printed on Ni foam by the doctor blade technique, forming a GO matrix embedded in Ni foam, which is then freeze-dried to turn into a 3-dimensional (3D) porous GO (3D-GO) matrix. NiFe-layered double hydroxide (NiFe-LDH) nanoflakes anchored on the 3D-GO matrix embedded in Ni foam are synthesized by a hydrothermal process, together with the in situ reduction of 3D-GO. The obtained electrode has a high degree of reduction of the porous graphene oxide, the mechanical strength of the NiFe-LDH nanoflakes anchored on the matrix, large active surface area and excellent interface conjunction. Based on optimal conditions, the fabricated electrode shows outstanding electrocatalytic oxygen evolution reaction performance in 1 M KOH aqueous solution, achieving a small overpotential of 170 mV, a Tafel slope of 57 mV decade−1 at a current density of 20 mA cm−2 and a relatively stable operating potential after 2000 cycles of the CV test.

A series of silicotungstic acid modified CeO2 (SC-x, x represents the pH value of solution that is used for the preparation of catalysts) were prepared for the selective catalytic reduction (SCR) of NOx with NH3. SC-9 showed the best catalytic activity among the samples. The monodentate nitrate, bidentate nitrate, bridging nitrate and NO2 were detected over SC-9 and SC-10. Monodentate nitrate and bridging nitrate disappeared over SC-8. Furthermore, the monodentate nitrate and bridging nitrate could react with NH4+ on Bronsted acid sites to generate NH4NO3, and then was reduced by NO to form NO2, accompanied with the fast reaction between NO2 and coordinated NH3 on Lewis acid sites in the presence of gaseous NO. Besides, the SCR reaction pathway of SC catalysts followed by the Langmuir–Hinshelwood mechanism and the Eley–Rideal mechanism.

Mannan is one of the major constituent groups of hemicellulose, which is a renewable resource from higher plants. β-Mannanases are enzymes capable of degrading lignocellulosic biomass. Here, an endo-β-mannanase from Rhizopus microsporus (RmMan134A) was cloned and expressed. The recombinant RmMan134A showed maximal activity at pH 5.0 and 50 °C, and exhibited high specific activity towards locust bean gum (2337 U/mg). To gain insight into the substrate-binding mechanism of RmMan134A, four complex structures (RmMan134A–M3, RmMan134A-M4, RmMan134A-M5 and RmMan134A-M6) were further solved. These structures showed that there were at least seven subsites (−3 to +4) in the catalytic groove of RmMan134A. Mannose in the −1 subsite hydrogen bonded with His113 and Tyr131, revealing a unique conformation. Lys48 and Val159 formed steric hindrance, which impedes to bond with galactose branches. In addition, the various binding modes of RmMan134A–M5 indicated that subsites −2 to +2 are indispensable during the hydrolytic process. The structure of RmMan134A–M4 showed that mannotetrose only binds at subsites +1 to +4, and RmMan134A could therefore not hydrolyze mannan oligosaccharides with degree of polymerization ≤4. Through rational design, the specific activity and optimal conditions of RmMan134A were significantly improved. The purpose of this paper is to investigate the structure and function of fungal GH family 134 β-1,4-mannanases, and substrate-binding mechanism of GH family 134 members.

A catalyst comprised of 4-dimethylaminopyridine (DMAP) functionalized silica gel (SG-DMAP) was prepared via a convenient N-alkylation of 4-methylaminopyridine (MAP) with γ-chloropropylated silica gel promoted by potassium iodide. FT-IR, TG, SEM results illustrated that the DMAP was successfully immobilized on silica gel and the BET result suggested the pore structure was not altered after immobilization process. The highest immobilization amount of 0.75 mmol/g was obtained at 130 °C for 12 h. Activity test demonstrated that silica gel immobilized DMAP could be serve as a heterogeneous catalyst for the acylation with significant activity and stability.

Herein, N-doped porous carbon (NC) decorated with ZnS, Ni3Fe, and metallic Ni, and denoted as ZnFeNiS/NC, was fabricated via the direct carbonization of a zeolitic imidazolate framework (ZIF-8), that is, a Zn-based metal–organic framework, combined with absorption and sulfurization processes. The synthesized material was used as an electrocatalyst for the hydrogen evolution reaction (HER) in alkaline solutions. Compared with Zn/NC, ZnFe/NC, and ZnFeNi/NC, ZnFeNiS/NC exhibited excellent HER activity with the lowest potential (162.57 mV) and Tafel slope (65.48 mV decade−1) at a current density of 10 mA cm−2. This better performance can be attributed to the synergistic effects of the ZnS, Ni3Fe, and Ni dopants; the ZnS, Ni3Fe, and Ni nanoparticles embedded in NC not only provided many active reaction sites but also ensured long-term stability in alkaline media. The new method presented here could allow the fabrication of non-noble-metal electrocatalysts with excellent electrocatalytic activity for HER.

The environmental-friendly hematite iron oxide (α-Fe2O3) has important application prospects in the photocatalysis field owing to its narrow indirect band gap. Here, we report a band gap engineering of α-Fe2O3 by incorporation of electrochemically-generated atomic hydrogen at moderate conditions. The ultraviolet–visible spectra show the reduction of the α-Fe2O3 band gap after hydrogenation and the absorption region from 200–800 nm is enhanced, especially in the visible light region. First principles calculation reveals the mixing of the new hybrid energy level with the valence band top resulting in a decrease in the band gap of α-Fe2O3. Further photocatalytic degradation experiments of dyes demonstrate that the photocatalytic efficiency of α-Fe2O3 can be greatly enhanced by the atomic hydrogen incorporation. The hydrogenated α-Fe2O3 can be easily recycled by magnets and has good photocatalytic stability. These findings offer possibilities for utilizing this inexpensive and earth-abundant oxide materials in the pollution controlling areas.

The reaction mechanism of non-aqueous Li-O2 batteries is based on the deposition and decomposition of Li2O2. The polarization of Li-O2 batteries can be rapidly increased by operation under a high rate condition, resulting in the early capacity fade of the cells. Therefore, a well-designed catalyst with a unique structure and excellent catalytic ability is an important way to boost the round-trip performance of Li-O2 batteries, especially under high current density. In this work, a unique nanoflower structure assembled with Co3O4 nanosheets is synthesized by using 2-methylimidazole (2-MIM) as a structural directing agent. X-ray photoelectron spectroscopy (XPS) and Raman spectra reveal abundant oxygen vacancies on the surface of the Co3O4 nanoflower, which are beneficial for oxygen reduction and evolution reactions and long round-trip lifetime. Density functional theory results demonstrate that Co3O4 catalyst with oxygen vacancies could promote the wetting of Li2O2 on substrate and formation of a Li2O2 nanofilm, thereby boosting the discharge capacity of Li-O2 batteries. On account of the synergistic effect of abundant oxygen vacancies, the unique structure, and excellent oxygen evolution reaction, Co3O4 nanoflower-based cells could deliver ultralong lifetime of 276 and 248 cycles with a discharge capacity of 1000 mAh g−1 under charge/discharge current densities of 0.5 A g−1 and 1 A g−1, respectively. This study has shed light on a new strategy for catalyst preparation for long lifetime Li-O2 batteries.

Vibrio splendidus is identified as one of the major pathogenic factors for the skin ulceration syndrome in sea cucumber (Apostichopus japonicus), which has vastly limited the development of the sea cucumber culture industry. In order to screen the immune genes involving Vibrio splendidus challenge in sea cucumber and explore the molecular mechanism of this process, the related transcriptome and gene expression profiling of resistant and susceptible biotypes of sea cucumber with Vibrio splendidus challenge were collected for analysis. A total of 319,455,942 trimmed reads were obtained, which were assembled into 186,658 contigs. After that, 89,891 representative contigs (without isoform) were clustered. The analysis of the gene expression profiling identified 358 differentially expression genes (DEGs) in the bacterial-resistant group, and 102 DEGs in the bacterial-susceptible group, compared with that in control group. According to the reported references and annotation information from BLAST, GO and KEGG, 30 putative bacterial-resistant genes and 19 putative bacterial-susceptible genes were identified from DEGs. The qRT-PCR results were consistent with the RNA-Seq results. Furthermore, many DGEs were involved in immune signaling related pathways, such as Endocytosis, Lysosome, MAPK, Chemokine and the ERBB signaling pathway.

A series of Co-mordenite (MOR) catalysts prepared by ion-exchange or impregnation methods were used in the selective catalytic reaction of NO with methane (CH 4 -SCR). The structure and physicochemical properties of the catalysts were examined by X-ray diffraction (XRD), X-ray fluorescence (XRF), scanning electron microscopy (SEM), UV-Raman spectroscopy, X-ray photoelectron spectroscopy (XPS), and temperature-programmed desorption of NO (NO-TPD). The Co species in the catalyst prepared by impregnation is present as Co 3 O 4 , whereas in the catalyst prepared by an ion-exchange method, the Co species enter in the mordenite skeleton with the ion form, and the more Co 2+ and [Co-O-Co] 2+ formed in the catalysts, the more uniform the adsorption of NO centers and the active centers of CH 4 -SCR. The catalysts prepared by different methods exhibited different activities for CH 4 -SCR. The catalysts prepared by ion-exchange exhibited activity over a wide activity temperature region, and NO conversion was over 50% at 327-450 °C on the Co(0.30)-MOR catalyst.

In a typical chemical vapour deposition (CVD) process for synthesizing carbon nanotubes (CNTs), it was found that the aromatization catalysts could promote effectively the formation of CNT. The essence of this phenomenon was attributed to the fact that the aromatization catalyst can accelerate the dehydrogenation–cyclization and condensation reaction of carbon source, which belongs to a necessary step in the formation of CNTs. In this work, aromatization catalysts, H-beta zeolite, HZSM-5 zeolite and organically modified montmorillonite (OMMT) were chosen to investigate their effects on the formation of multi-walled carbon nanotubes (MWCNTs) via pyrolysis method when polypropylene and 1-hexene as carbon source and Ni2O3 as the charring catalyst. The results demonstrated that the combination of those aromatization catalysts with nickel catalyst can effectively improve the formation of MWCNTs.

α-Fe2O3 samples with nanocube and nanorod morphologies were synthesized by a simple hydrothermal route.The samples were characterized by powder X-ray diffraction (XRD),field emission scanning electron microscopy (FE-SEM),high-resolution transmission electron microscopy (HRTEM),temperature-programmed reduction by H2 (H2-TPR),and temperature-programmed desorption of NO (NO-TPD),and tested for the selective catalytic reduction with NH3 (NH3-SCR) of NO at moderate temperatures.The α-Fe2O3 nanocubes possessed predominantly exposed {012} faces with low surface energy,while the nanorods also had some high energy {110} faces exposed.The catalytic activities of the α-Fe2O3 samples were predominantly governed by their surface structures.The nanorods showed much higher activity than the nanocubes under identical conditions,consistent with the better redox properties of the nanorods as confirmed by H2-TPR and NO-TPD measurements.Therefore,α-Fe2O3 nanorods with exposed high energy faces have much higher activity for NH3-SCR than nanocubes with exposed low energy faces under identical reaction conditions.

The commercially available ferrocene-based diphosphine ligand (Sc,SFc)-TaniaPhos was found to be highly effective in the Rh-catalyzed asymmetric hydrogenation of 3-aryl-2-(phosphonomethyl)propenates. Excellent enantioselectivity (90–98% ee) and high catalytic activity (S/C up to 1000) have been achieved, which represents the best results reported so far.

Twenty microsatellite DNA markers were developed for sea cucumber and used to investigate polymorphisms of 60 wild Apostichopus japonicus individuals collected from China. It revealed that all the markers were polymorphic. A total of 164 alleles were detected at 20 loci. The number of alleles per locus varied from 3 to 17 with an average of 8.2, and the expected heterozygosities of each locus ranged from 0.03 to 0.89 with an average of 0.64. Cross-species amplification was also conducted in Parastichopus parvimensis collected from the United States and Pathallus mollis collected from Peru. The result showed that 17 loci amplified Parastichopus parvimensis DNAs while only 4 loci could amplify Pathallus mollis DNAs. All of the polymorphic markers would be useful for future genetic breeding and the assessment of genetic variation within sea cucumbers.

TS-1 monolithic catalysts were prepared on cordierites honeycomb ceramics supports by dip-coating method in TS-1/H2O suspension. The cordierites honeycomb ceramics supports were treated with different methods, such as coated with a thin layer of sodium silicate, immersed in 0.5N hydrochloric acid. The monolithic catalysts were characterized by Scanning Electron Microscopy. The distribution of TS-1 Catalysts onto supported was observed. The immobilized stability of TS-1 monolithic catalysts was evaluated by ultrasonic cleaning and washing out experiment. TS-1 catalysts were uniformly deposited onto inner smoothed surface of cordierites honeycomb ceramics supports, which ware coated sodium silicate film. And experiment data proved that TS-1 catalysts may be firmly immobilized onto supports coated sodium silicate.

Trisiloxane surfactants can significantly enhance the biological activity of pesticides, in order to optimize of synthesis technology,in this paper,there was no gas protection,cleared trisiloxane surfactants optimization conditions by took the sample at different reaction time and measured degree of reaction degree by chemical titration method,infrared spectroscopy characterized,deteminated surface tension and controled weeds. This technology is more convenient than existent technology.The best reaction conditions:catalyst was 10mg/L,reaction temperature was 80 ,material ratio was 1:1.2, reaction time was 5 hours,the degree of their response would totally up to 93.83%.The surface tension compared with Silwet408 no significant difference to water and liquid. Different reaction degree trisiloxane surfactant could increased weed control of fomesafen differently.When added reaction degree 93% trisiloxane surfactant,dosage 1‰((v/v),enhanced observing 28.5% and fresh weight 29.5% than 252g ai/hm-2 only treated.Thus,this method could be used in production of trisiloxane surfactants.

A series of new chiral phosphine-aminophosphine ligands have been prepared via a two- or three-step transformation from commercially available and inexpensive (S)-1-phenylethylamine, and successfully used in the rhodium-catalyzed asymmetric hydrogenation of various enamides, beta-dehydroamino acid esters, and dimethyl itaconate. The results show that the ligand structure plays an important influence on both the reactivity and enantioselectivity. Ligand 2d bearing a N-H proton and two F-atoms on the 3,5-positions of the phenyl ring of the aminophosphino moiety was most effective for the hydrogenation of enamides and (Z)-beta-aryl-beta-(acylamino)acrylates, whereas ligand lb showed the highest enantioselectivities in the hydrogenation of (Z)-beta-alkyl-beta-(acylamino)acrylates and dimethyl itaconate. (C) 2010 Elsevier Ltd. All rights reserved.

From the dried roots of Euphorbia nematocypha, eight new diterpenoids, with ent-atisane (i.e., 1–5) and isopimarane (i.e., 6–8) type skeletons, together with five known compounds, were isolated. The structures of these new compounds were elucidated by spectroscopic data. Compounds 1–8 were evaluated for their cytotoxicity against a small panel of human cancer cell lines.

Two new 6,7-seco-ent-kaurane diterpenoids, isojaponins A (1) and B (2), together with 18 known ent-kaurane diterpenoids were isolated from the aerial parts of Isodon japonicus. The structures of the two new compounds were elucidated by extensive 1D- and 2D-NMR spectroscopic methods in combination with MS experiments.

A clean and efficient method for the synthesis of 2-amino-4-aryl-3-cyano-5-oxo- 4H-5,6,7,8- tetrahydrobenzopyran derivatives using hexadecyldimethylbenzyl ammonium bromide (HDMBAB) as the catalyst is described. This method provides several advantages, such as simple work-up procedure, environmentally benign, neutral conditions and high yields. In addition, water was chosen as a green solvent.

A series of substituted 5-oxo-1,4,5,6,7,8-hexahydroquinoline derivatives have been synthesized from 1,3-diaryl-2-propen-1-one and 5,5-dimethyl-1,3-cyclohexanedione in the presence of ammonium acetate by solid state reaction at 80 ° C with high yields (82-92%) without using solvent and catalyst. This method provides several advantages such as operational simplicity, neutral condition, high yields and environment friendly.

A general and practical chemical route to the synthesis of N‐sulfonylimines using montmorillonite K‐10 as the catalyst is described. This method provides several advantages such as operational simplicity, short reaction time, using of inexpensive materials, noncorrosivity, lack of pollution, and high yields.

A general and practical one‐pot synthesis of naphthopyran derivatives using hexadecyltrimethylammonium bromide (HTMAB) as catalyst (10 mol%) is described. This method provides several advantages such as neutral conditions, high yields and simple workup procedure. The catalyst is low cost, facile, active, environmentally friendly, and reusable. In addition, water is chosen as a green solvent.

The reaction of aromatic aldehyde and 1,3-cyclohexanedione in aqueous media has been catalyzed byp-dodecylbenezenesulfonic acid (DBSA) or sodium dodecyl sulfate (SDS) and yields two products: 9-aryl-1, 8-dioxooctahydroxanthene derivatives and 2,2´-arylmethylenebis(3-hydroxy- 2-cyclohexene-1-one). This method provides several advantages such as good yield, simple work-up procedure and environment friendly.

An efficient and convenient synthetic route to 4H‐pyran derivatives in water in the presence of hexadecyltrimethyl ammonium bromide (HTMAB) as catalyst is described. This method provides several advantages such as environment friendliness, high yields, and a simple workup procedure. In addition, water was chosen as a green solvent.