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In the present study, the hypoglycemic effects of glucomannan (AGM) and its enzyme-degraded products from Amorphophallus albus were investigated. Four degraded products were prepared through ultrafiltration of β-glucanase-degraded products of AGM. The hypoglycemic activities were evaluated in HFD-STZ-induced type 2 diabetes mellitus (T2DM) mice, and the diversity of gut bacteria was analyzed by 16S rRNA gene sequencing; the fecal short chain fatty acids (SCFAs) and endogenous metabolites were determined by UPLC-QTOF-MS/MS. It was found that AGM and its enzyme-degraded products, though with different molecular weights, had similar β-glycosidic bonds and monosaccharide compositions, exerted similar strength of hypoglycemic effects, and reinstated with a similar extent the disordered gut microbiota and the contents of SCFAs and endogenous metabolites. It was speculated that the hypoglycemic activity of AGM is decided by not the molecular weight but the glycosidic bonds/monosaccharide composition of AGM, which might be structurally specific to the gut bacteria, and thus certain SCFAs and endogenous metabolites that are related to the occurrence and therapy of T2DM. This study provides a scientific basis for using AGM as potential prebiotics beneficial for prevention or therapeutic treatment of T2DM.

The polar modified dendritic post-cross-linked polymer, namely HCPD was synthesized and used for adsorptive removal of Cu2+ from aqueous solution. The results showed that 5.12 mmol/g of amino and 2.25 mmol/g of carbonyl groups were uploaded on the polymer and these groups were significantly beneficial for Cu2+ removal. The maximum capacity reached 157.8 mg/g at 313 K and increased as the temperature increased. The Langmuir model characterized the equilibrium data well and a chemical interaction was involved with the enthalpy change of 49.50 kJ/mol. The pseudo-second-order kinetic model described the kinetic data well and the intra-particle diffusion model was appropriate for characterizing the kinetic adsorption. HCPD could be easily regenerated and the regenerated polymers were effectively recycled for five times without significant loss of the equilibrium capacity. Moreover, Fourier-transform infrared (FT–IR) and X-ray photoelectron spectroscopy (XPS) results revealed that the chelating coordination of the amino and carbonyl groups with Cu2+ was the main driving force for the adsorption.

By a pilot trial on investigating immunomodulatory activity and target of ginsenosides, the major bioactive components of ginseng, here we report that structural analogues in herbal medicines hit a shared target to achieve cumulative bioactivity. A ginsenoside analogues combination with definite immunomodulatory activity in vivo was designed by integrating pharmacodynamics, serum pharmacochemistry and pharmacokinetics approaches. The cumulative bioactivity of the ginsenoside analogues was validated on LPS/ATP-induced RAW264.7 macrophages. The potentially shared target NLRP3 involved in this immunomodulatory activity was predicted by systems pharmacology. The steady binding affinity between each ginsenoside and NLRP3 was defined by molecular docking and bio-layer interferometry assay. The activation of NLRP3 inflammasomes in LPS/ATP-induced RAW264.7 was significantly suppressed by the combination, but not by any individual, and the overexpression of NLRP3 counteracted the immunomodulatory activity of the combination. All these results demonstrate that the ginsenoside analogues jointly hit NLRP3 to achieve cumulative immunomodulatory activity., Zhang et al. design ginsenoside structural analogues and demonstrate that their combination shows more potent immunomodulatory activities than individual ginsenosides used alone at the same dosages. They predict that these analogues act on the joint target NLRP3 and consequently suggest that structural analogues hit a shared target to achieve cumulative bioactivity.

Porous silicate supported micro-nano zero-valent iron (PSi@ZVI) was prepared from copper slag (CS) through carbothermal reduction technology, and used as a persulfate (PS) activator for removing organic contaminants. Results showed that the properties of the activator were greatly affected by the preparation conditions. Calcination for 20 min at 1100 °C with 20% anthracite was considered the optimum preparation condition for degradation of orange G (OG). The removal rate of OG was improved by increasing the dosages of PSi@ZVI or PS and raising the reaction temperature. Moreover, PSi@ZVI exhibited excellent PS activator ability in a wide range of initial pH, good degradation capability for eosin Y, methyl orange, acid fuchsine, and methylene blue. The reusability and safety of PSi@ZVI were verified. Electron paramagnetic resonance and radical quenching tests indicated that sulfate radical (SO4 −) was the main active species in the PSi@ZVI/PS system. The X-ray diffraction results indicated that a high calcination temperature (1100 °C) was beneficial to the reduction of iron-bearing minerals to ZVI. Scanning electron microscopy and energy-dispersive spectroscopy results revealed that the formation of porous structure of PSi@ZVI and the generation of nano to micro-sized ZVI particles on the surface of the silicate holes. The X-ray photoelectron spectra showed that ZVI was first convert into Fe(II), which mainly activated PS and generated Fe(III) in the PSi@ZVI/PS system. Furthermore, the intermediates of OG were detected using gas chromatography–mass spectrometry, and the possible degradation pathway of OG was proposed. This study provides a novel approach for reuse of CS as a heterogeneous activator to effectively activate PS.

Ethnopharmacological relevance Poria cocos (Schw.) Wolf (Poria) is a well-known traditional medicinal fungus. It has been considered to possess spleen-invigorating (Jianpi) effects in traditional Chinese medicine, and is used clinically to treat spleen deficiency (Pixu) with symptoms of intestinal disorders such as diarrhea, indigestion, mucositis and weight loss. The aim of this study To investigate the protective effects of Poria and its three component fractions (Water-soluble polysaccharides, WP; alkali-soluble polysaccharides, AP; triterpene acids, TA) on cisplatin-induced intestinal injury and explore the underlying mechanisms. Materials and methods C57BL/6 mice were treated with Poria powder (PP), WP, AP and TA by oral gavage respectively for 13 days, and intraperitoneally injected with 10 mg/kg of cisplatin on day 10 to conduct a cisplatin-induced intestinal injury model. Pathological changes of ileum and colon were examined using H&E staining. The composition of gut microbiota and the alteration of host metabolites were characterized by 16S rDNA amplicon sequencing and UPLC-QTOF-MS/MS based untargeted metabolomics analysis. Results PP and WP attenuated the cisplatin-induced ileum and colon injury, and WP alleviated the weight loss and reversed the elevation of IL-2, IL-6 in serum. Both PP and WP could mitigate cisplatin-induced dysbiosis of gut microbiota, in particular PP and WP decreased the abundance of pathogenic bacteria including Proteobacteria, Cyanobacteria, Ruminococcaceae and Helicobacteraceae, while WP promoted the abundance of probiotics, such as Erysipelotrichaceae and Prevotellaceae. Moreover, WP attenuated the cisplatin-induced alteration of metabolic profiles. The levels of potential biomarkers, including xanthine, L-tyrosine, uridine, hypoxanthine, butyrylcarnitine, lysoPC (18:0), linoleic acid, (R)-3-hydroxybutyric acid, D-ribose, thiamine monophosphate, indolelactic acid and plamitic acid, showed significant correlations with intestinal flora. Conclusions PP and WP possess protective effects against cisplatin-induced intestinal injury via potentially regulating the gut microbiota and metabolic profiles.

A novel magnetic molecularly imprinted electrochemical sensor (MMIP-sensor) combined with magnetic molecularly imprinted solid-phase extraction (MMISPE) was constructed for rapid and sensitive detection of tetrabromobisphenol S (TBBPS) in water samples. The magnetic molecularly imprinted polymer based on magnetic graphene/multi-walled carbon nanotubes hybrid composite (MMIP/Gr-MWCNTs) was prepared as MMISPE sorbet to separate and enrich TBBPS from complex system. Adsorption results showed that the MMIP/Gr-MWCNTs possessed excellent selective adsorption toward TBBPS with a maximum adsorption capacity of 17.83 mg g − 1 . The magnetic imprinted sensor based on the magnetic Gr-MWCNTs composite modified electrode was prepared by electropolymerization of dopamine monomer. The high sensitivity of the MMIP-sensor was attributed to the large specific surface area and excellent electrical conductivity of the magnetic Gr-MWCNTs composites. The detection limit of the MIP-sensor toward TBBPS was calculated as 2.1 × 10 − 11 mol L − 1 (S/N = 3). Under the optimum conditions, the MISPE-MMIP-sensor combination system provided 10–12 fold preconcentration than that of MMIP-sensor alone determination. The MISPE-MMIP-sensor was successfully used for detection of TBBPS in drinking water, rain water, lake water and tap water with recoveries of 88.4–98.8%.

Screening and deciphering active natural products of herbal medicines are of great importance for modern drug discovery. In this study, a novel strategy was proposed to rapidly filter ineffective compounds and target the most potential leads. The aim is to answer the key question of what components are responsible for the holistic bioactivity of an herbal product. To support the strategy, the pharmacophore-guided knockout/knockin chromatography was established for the first time. The greatest advantage of this method is that any interesting components could be automatically fished or knocked out. The method validation shows that the herbal extract was accurately reconstructed according to the experimental design. By combining with bioactivity assays, we demonstrated that "functional compound combination (FCC)", which is the core and indispensable effective part, could be discovered from an herbal medicine and suitable as marker compounds for quality control. The applicable objects of the strategy include single herbs, herbal formulas and commercially herbal preparations. As an illustrative case study, the strategy was successfully applied to simultaneously determine active leads and the FCC in Dan-Qi formula which shows excellent free radical scavenging activity. The potential mechanisms of compounds in Dan-Qi formula reacting with three different free radicals were systematically reported for the first time. This strategy was expected to unveil the mystery of herbal medicines and inspire a natural product-based drug discovery.

A novel three-dimensional (3D) magnetic chlorogenic acid (CGA) imprinted polymer (MMIP) was prepared with novel carbon hybrid nanocomposite as the carrier, chlorogenic acid as the template molecule, and methacrylic acid as the functional monomer. The 3D MMIPs were characterized by scanning electron microscopy, Fourier transform infrared spectroscopy, thermogravimetric analysis, vibrating sample magnetometer, and UV spectrometry in detail. The results showed that the imprinted layer was attached successfully on the surface of a 3D magnetic carbon hybrid nanocomposite. The adsorption performance of the 3D MMIPs was investigated, and the results showed that the 3D MMIPs exhibited high adsorption capacity and fast adsorption rate toward CGA with a maximum adsorption capacity of 10.88 mg g(-1). The extraction conditions involving washing solvent, the pH of eluent solvent, elution volume, and desorption time were also investigated in detail. Combined with high-performance liquid chromatography, the 3D MMIPs have been applied to successfully extract CGA from Eucommia leaf extract samples.

Most amino acids contain chiral centres and exist as both D-enantiomer and L-enantiomer. The optically pure enantiomer is often more valuable than the racemate. Enzymatic resolution provides an effective strategy to obtain optically pure amino acids but often results in large amounts of unwanted isomer. In this study, optically pure L-glufosinate (L-PPT) was obtained by coupling amidase-mediated hydrolysis of N-phenylacetyl-D,L-glufosinate with racemization of N-phenylacetyl-D-glufosinate (NPDG), which exclusively exhibits effective herbicidal properties compared with its D-enantiomer. To improve the yield of L-PPT, the racemization reaction conditions were optimized, and through single-factor experiments, the optimal reaction temperature, reaction time, and mole ratio of phenylacetic acid to NPDG were determined to be 150°C, 30 minutes, and 1.5, respectively. The response surface methodology was applied to further optimize the racemization conditions, and the final yield of L-PPT reached 96.13% with optimum reaction temperature of 154°C, reaction time of 23 minutes, and phenylacetic acid/NPDG mole ratio of 1.7, respectively. Moreover, adding a small amount of acetic anhydride further raised the yield of L-PPT to 97.02%.

Introduction Triterpene acids from the dried sclerotia of Poria cocos (Schw.) Wolf (poria) were recently found to possess anti-cancer activities. Identification of more triterpene acid analogues in poria is worthwhile for high throughput screening in anti-cancer drug discovery. Objective To establish an efficient dereplication strategy for identifying triterpene acid analogues in poria based on ultra-performance liquid chromatography with electrospray ionisation quadrupole time-of-flight tandem mass spectrometry (UPLC-ESI-QTOF-MS/MS). Methodology The structural characteristics and mass spectrometric data profiles of known triterpene acids previously reported in poria were used to establish a predicted-analogue database. Then, the quasi-molecular ions of components in a poria extract were automatically compared with those in the predicted-analogue database to highlight compounds of potential interest. Tentative structural identification of the compounds of potential interest and discrimination of isomers were achieved by assessing ion fragmentation patterns and chromatographic behaviour prediction based on structure-retention relationship. Results A total of 62 triterpene acids were unequivocally or tentatively characterised from poria, among which 17 triterpene acids were tentatively identified for the first time in poria. Conclusion This study provided more structure information of triterpene acids in poria for future high throughput screening of anti-cancer candidates. It is suggested that this semi-automated approach in which MS data are automatically compared to a predictive database may also be applicable for efficient screening of other herbal medicines for structural analogues of proven bioactives.

In traditional Chinese medicine practice, crude herbs are often subjected to traditional processing (Paozhi in Chinese) for a special medicinal purpose. Bran-frying is one of processing methods for Paeoniae Radix Alba (PRA). Previous studies found that paeoniflorin and paeoniflorin sulfonate, a principle bioactive compound and its sulfur-fumigation induced characteristic sulfur-containing derivative, could be used together with sulfur dioxide residue as chemical markers for the quality control of sulfur-fumigated PRA crude material. In this paper, the feasibility of these three markers used for the quality control of bran-fried sulfur-fumigated PRA was further investigated. First, homemade samples of sulfur-fumigated PRA with different sulfur-fumigation duration (0.5-6 h) were bran-fried, and stored for 12 months. Second, the contents of sulfur dioxide residue, paeoniflorin and paeoniflorin sulfonate were dynamically quantified respectively. Third, the variation of the marker contents and their correlation during bran-frying and storage was evaluated. A validation was conducted using commercial bran-fried PRA samples. The results showed that bran-frying caused an averaged reduction of 20% in the content of sulfur dioxide residue, and during the first two months of storage the content of sulfur dioxide residue was decreased by up to 27%, then the content was tending towards stability for the subsequent ten months of storage (RSD = 3.92%). Meanwhile, paeoniflorin and paeoniflorin sulfonate were relatively stable, the contents of which were not affected by bran-frying processing and 12 months of storage. The correlations between the contents of sulfur dioxide residue and paeoniflorin/paeoniflorin sulfonate were obviously influenced by storage duration. Since sulfur dioxide residue is a safety marker, while paeoniflorin and paeoniflorin sulfonate can reflect the inner quality and the impact extent of sulfur-fumigation on the quality of bran-fried PRA respectively, these three chemicals might be used together as markers for the quality control, and consequently to ensure the safety and efficacy of bran-fried PRA.

A novel magnetic imprinted electrochemical sensor was developed based on magnetic multi-walled carbon nanotubes (MWCNTs) for sensitive determination of kanamycin in complicated matrixes. The magnetic molecularly imprinted polymers (MMIPs) were prepared based on MWCNT decorated Fe3O4 nanoparticles using kanamycin as the template molecule and methacrylic acid (MAA) as the functional monomer. The performance of the imprinted sensor was investigated using cyclic voltammetry (CV) and differential pulse voltammetry (DPV) in detail. The sensitivity of the magnetic imprinted electrochemical sensor was improved attributing to the large specific surface area and excellent electrical conductivity of the Fe3O4 nanoparticles and multi-walled carbon nanotubes (MWCNTs). Under the optimum conditions, the response currents of the magnetic imprinted electrochemical sensor exhibited a linear relationship toward the negative logarithm of kanamycin concentrations ranged from 1.0 × 10− 10 mol L− 1 to 1.0 × 10− 6 mol L− 1 with a detection limit of 2.3 × 10− 11 mol L− 1 (signal to noise ratio is 3). The magnetic imprinted electrochemical sensor was applied to detect trace kanamycin in real samples successfully with the recoveries of 92.5–105.3%.

Objective: To establish a rapid, accurate and reliable analytical method for the simultaneous determination of four major anthraquinones in Polygoni Multiflori Radix (PMR) using single reference standard. Methods: The four components including emodin-8-O-β-D- (EMG), physcion-8-O-β-D-glucoside, emodin and physcion were separated on an ODS C18 column within 13 min and detected at 280 nm. Emodin was selected as the reference standard, and the response factor for each analyte with respect to emodin were calculated. Robustness were also tested including different columns, equipments, temperatures, detection wavelengths, and other chromatographic conditions which might influence stability of response factors. Results: The method was validated in terms of linearity (r2 > 0.9995), LOQs (0.820–3.05 ng/mL), LODs (0.180–0.920 ng/mL), precision, accuracy (95.8–103.6%, RSD Conclusion: This work provided a single standard to determine multi-components method for quantitation of four anthraquinones in PMR, which could be applied in the quality control of this herbal drug.

Background: Soluble epoxide hydrolase (sEH) has been demonstrated to be a key enzyme involved in the pathologic development of several cardiovascular diseases and inflammation, and inhibition of sEH is therefore very helpful or crucial for the treatment of ischemia-reperfusion injury, cardiac hypertrophy, hypertension and inflammation. Danshen, the dried root of Salvia miltiorrhiza (Fam. Labiatae ), has been used for the treatment of cardiovascular and cerebrovascular diseases in China and other countries for hundreds of years. Recent studies indicated that Danshen and its preparations also have potential for the management of inflammation. However, little information is available about the possibility of Danshen and its components on sEH inhibition. Purpose and methods: Danshen extracts and its constituents were tested for sEH inhibition using its physiological substrate, 8,9-EET, based on a LC–MS/MS assay in this study. Results: Among the tested 15 compounds, tanshinone IIA and cryptotanshinone were found to be the potent ( K i = 0.87 μM) and medium ( K i = 6.7 μM) mixed-type inhibitors of sEH, respectively. Salvianolic acid C ( K i = 8.6 μM) was proved to be a moderate noncompetitive sEH inhibitor. In consistent with the inhibition results of the pure compounds, the 75% ethanol extract of Danshen (EE, IC 50 = 86.5 μg/ml) which contained more tanshinone IIA and cryptotanshinone exhibited more potent inhibition on sEH than the water extract (WE, IC 50 > 200 μg/ml) or 1 M NaHCO 3 (BE, IC 50 > 200 μg/ml) extract. Conclusion: These data indicated that using the ethanol fraction of Danshen and increasing the amounts of tanshinone IIA, cryptotanshinone and salvianolic acid C, especially the contents of tanshinone IIA in Danshen extract or preparations to enhance the inhibitory effects on sEH might be efficient ways to improve its cardiovascular protective and anti-inflammatory effects, and that herbal medicines could be an untapped reservoir for sEH-inhibition agents and developing sEH inhibitors from the cardiovascular protective and anti-inflammatory herbs is a promising approach.

A series of reactive pour point depressants (PPD) with anhydride group were prepared, and their action mechanism had been investigated by Fourier transform infrared spectroscopy (FTIR), differential scanning calorimeter (DSC) and cross-polarized light microscope. The results showed that the prepared pour point depressants had obvious pour point depressing effect on crude oil. Its action mechanism was concluded that PPD could react with the resin and asphaltene in the crude oil to generate a new macromolecule when crude oil was treated with PPD-3 at 90 °C. The new macromolecule further formed a new agglomerate structure by association with the asphaltene and resin in crude oil, which worked as a new nucleator to provide nucleation sites for wax crystal instead of the original asphaltene–resin agglomerate structure, and then improved the flowability of crude oil.

Generally, gas-water relative permeability curves of tight gas reservoirs are obtained from unsteady experiment under room temperature and normal pressure, which greatly differs from the curves under high temperature and high pressure. In this research, the relative permeability curves of three cores were firstly measured using conventional standard method by displacing formation water with nitrogen under room temperature and normal pressure. Then the relative permeability curves of the same cores were measured by displacing formation water with natural gas on one self-developed full-diameter seepage flow equipment (200 °C, 200 MPa) under reservoir conditions (160 °C, 116 MPa) after several processing of the cores. Difference between the relative permeability curves obtained by the two methods shows that, under high temperature and high pressure, there exists a larger two-phase seepage zone and lower irreducible water saturation. At the same gas saturation, gas relative permeability under high temperature and high pressure is higher than that under room temperature and normal pressure, which means, under reservoir situation, the two-phase flow ability of gas and water is stronger and the irreducible water saturation is lower in tight gas reservoirs. The gas-water viscosity ratio, gas-water density ratio and interfacial tension are lower under this situation, which leads to higher sweep efficiency. Key words: high temperature, high pressure, tight gas reservoir, unsteady state, gas-water relative permeability, full-diameter core

We developed a SMEDDS to enhance the oral delivery of resveratrol by using high performance liquid chromatography, a pseudo ternary phase diagram and a central composite design (CCD). We found that the optimal formulation of 12.69% greoil gtcc, 62.29% Cremophor EL, and 25.02% Labrasol. We characterized the particle size and zeta potential of the final SMEDDS.

Our group was the first one reporting that autophagy could be triggered by airborne fine particulate matter (PM) with a mean diameter of less than 2.5 μm (PM2.5) in human lung epithelial A549 cells, which could potentially lead to cell death. In the present study, we further explored the potential interactions between autophagy and apoptosis because it was well documented that PM2.5 could induce apoptosis in A549 cells. Much to our surprise, we found that PM2.5-exposure caused oxidative stress, resulting in activation of multiple cell death pathways in A549 cells, that is, the tumor necrosis factor-alpha (TNF-α)-induced pathway as evidenced by TNF-α secretion and activation of caspase-8 and -3, the intrinsic apoptosis pathway as evidenced by increased expression of pro-apoptotic protein Bax, decreased expression of anti-apoptotic protein Bcl-2, disruption of mitochondrial membrane potential, and activation of caspase-9 and -3, and autophagy as evidenced by an increased number of double-membrane vesicles, accompanied by increases of conversion and punctuation of microtubule-associated proteins light chain 3 (LC3) and expression of Beclin 1. It appears that reactive oxygen species (ROS) function as signaling molecules for all the three pathways because pretreatment with N-acetylcysteine, a scavenger of ROS, almost completely abolished TNF-α secretion and significantly reduced the number of apoptotic and autophagic cells. In another aspect, inhibiting autophagy with 3-methyladenine, a specific autophagy inhibitor, enhanced PM2.5-induced apoptosis and cytotoxicity. Intriguingly, neutralization of TNF-α with an anti-TNF-α special antibody not only abolished activation of caspase-8, but also drastically reduced LC3-II conversion. Thus, the present study has provided novel insights into the mechanism of cytotoxicity and even pathogenesis of diseases associated with PM2.5 exposure.

S, Sr-codoped TiO2 were prepared by sol-gel mothod, using titanium (IV) n-butoxide, strontium nitrate and thiourea as precursors. And the samples were characterized by X-ray diffraction (XRD), Fourier infrared spectroscopy (FTIR), scanning electron microscopy (SEM). The results showed that the S, Sr-codoped TiO2 were single-phase anatase structure, and the particle growth and crystal phase transformation can be restrained by doping. The photocatalytic activity and reusability of the catalysts under UV light (365nm) was investigated with methyl orange as the model compound. The results showed that S, Sr-codoped TiO2 had the highest photocatalytic activity among all as-prepared samples. The kinetic study showed that this photocatalytic process coincided with the Langmuir-Hinshelwood (L-H) pseudo first order reaction model.

Ginger (Zingiberis Rhizoma), a commonly-consumed food supplement, is often sulphur-fumigated during post-harvest handling, but it remains unknown if sulphur fumigation induces chemical transformations in ginger. In this study, the effects of sulphur fumigation on ginger chemicals were investigated by ultra-high performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry (UHPLC-QTOF-MS/MS)-based metabolomics. The results showed that sulphur fumigation significantly altered the holistic chemical profile of ginger by triggering chemical transformations of certain original components. 6-Gingesulphonic acid, previously reported as a naturally-occurring component in ginger, was revealed to be a sulphur fumigation-induced artificial derivative, which was deduced to be generated by electrophilic addition of 6-shogaol to sulphurous acid. Using UHPLC-QTOF-MS/MS extracting ion analysis with 6-gingesulphonic acid as a characteristic chemical marker, all the commercial ginger samples inspected were determined to be sulphur-fumigated. The research outcomes provide a chemical basis for further comprehensive safety and efficacy evaluations of sulphur-fumigated ginger.

The three-step upright cup method was employed to determine the total moisture transfer resistance and the two air layer resistances on both sides of the membrane. The effective moisture diffusion coefficient in air layer between the membrane and water surface was determined by the regressive method, and the effective moisture diffusion coefficient of membrane was calculated. Experiments were conducted on a non-porous hydrophilic thermoplastic polyester elastomer membrane. The moisture transfer process through the membrane was modeled by using the solution-diffusion model. The effects of membrane microstructure on membrane permeation were analyzed based on the solution-diffusion model and experimental data. The results show that the effective diffusion coefficient can be used to evaluate the mass transfer process through the non-porous hydrophilic thermoplastic polyester elastomer membrane.

Sulfur fumigation can induce chemical transformation of bioactive components, consequently the alteration of bioactivities or even toxicities of medicinal herbs. Inspecting Chinese patent medicines (CPM) contained sulfur-fumigated constituent herbs is crucial for ensuring the safety and efficacy of CPM. Paeonifiorin sulfonate is a sulfur-fumigation induced compound of Moutan Cortex (MC), one of the main constituent herbs of a commonly used CPM Liu-Wei-Di-Huang-Wan (LWDHW). Herein, we investigated the approach of paeonifiorin sulfonate as a characteristic marker for specifically inspecting LWDHW potentially contained sulfur-fumigated MC (SFMC). First, mimic LWDHW samples contained SFMC (SFMC-LWDHW) and non-fumigated MC (NFMC-LWDHW) were prepared respectively. Second, an LC-MS method was developed and validated to qualitatively and quantitatively determine paeonifiorin sulfonate in the mimic LWDHW samples. Third, the established method was applied to analyze the commercial LWDHW samples. The results showed that paeoniflorin sulfonate could only be detectable in SFMC-LWDHW, but not in NFMC-LWDHW samples. The CPM matrix could enhance the response of paeoniflorin sulfonate in mass spectrometry analysis. In addition, the LOQ, linearity, precision, accuracy and stability were also demonstrated to be acceptable for quantifying paeoniflorin sulfonate in LWDHW. Commercial samples analysis indicated that paeoniflorin sulfonate were detectable in 9 of 10 commercial LWDHW samples, with the content varied between 105.53μg/g and 438.61μg/g. All the results suggested that paeoniflorin sulfonate could be used as a characteristic and reliable chemical marker for specifically inspecting commercial LWDHW contained SFMC. This study also provides a new strategy for the quality control of other CPMs potentially produced from sulfur-fumigated constituent herbs.

Biological therapies can be beneficial in cancer patients. The present study aims to examine the inhibitory mechanism of curcumin on cancer cells in patients with colorectal cancer. The results showed that curcumin administration increased body weight, decreased serum TNF-alpha levels, increased apoptotic tumor cells, enhanced expression of p53 molecule in tumor tissue, and modulated tumor cell apoptotic pathway. We conclude that the curcumin treatment improves the general health of patients with colorectal cancer via the mechanism of increased p53 molecule expression in tumor cells and consequently speeds up tumor cell apoptosis.

A series of novel azobicyclo[3.3.0]octane derivatives were synthesized and evaluated as dipeptidyl peptidase 4 (DPP-4) inhibitors. The effort resulted in the discovery of inhibitor 2a, which exhibited excellent efficacies in an oral glucose tolerance test. Introduction of methyl group (2j) could prolong the inhibition of serum DPP-4 activity.

An efficient stereoselective synthesis of the rigid aza-bicyclo[3.2.0]heptane scaffold has been developed to provide 2-cyano pyrrolidine alpha-amino amide 1 as DPP-4 inhibitor.

Tillage systems can influence C sequestration by changing aggregate formation and C distribution within the aggregate. This study was undertaken to explore the impact of no-tillage without straw (NT-S) and with straw (NT+S), and moldboard plow without straw (MP-S) and with straw (MP+S), on soil aggregation and aggregate-associated C after six years of double rice planting in a Hydragric Anthrosol in Guangxi, southwest of China. Soil samples of 0.00-0.05, 0.05-0.20 and 0.20-0.30 m layers were wet-sieved and divided into four aggregate-size classes, >2 mm, 2.00-0.25 mm, 0.25-0.053 and 2 mm aggregate fraction and reduced the proportion of 0.25 mm macroaggregate fraction also significantly increased in the 0.00-0.5 m layer in NT system. However, those within the 2.00-0.25 mm aggregate fraction were significantly reduced in the 0.05-0.200 m layer under NT system. Straw incorporation increased not only the SOC stock in bulk soil, but also the proportion of macroaggregate, aggregate associated with SOC and humic and fulvic acids concentration within the aggregate. The effect of straw on C sequestration might be dependent on the location of straw incorporation. In conclusion, the NT system increased the total SOC accumulation and humic and fulvic acids within macroaggregates, thus contributing to C sequestration in the 0.00-0.05 m layer.

Superjunction devices are reported to provide better high-voltage operation characteristics than conventional abrupt junction devices in silicon power applications. In this study, the superjunction reduced surface field (SJ-RESURF) lateral double diffused metal oxide semiconductor field effect transistor (LDMOSFET) is fabricated on a bulk silicon wafer to improve the operating characteristics of high-voltage devices. By introducing the p-type strips in the drift region, higher doping concentration of the drift region can be adopted to reduce the conduction resistance. The SJ-RESURF LDMOSFET with a specific on-resistance of 3.53 Ωmm2, a breakdown voltage of 335 V and a drift length of 30 µm, is demonstrated; its turn on-resistance is 25% better than that of the conventional structure. The turn-on resistance, breakdown behavior, device geometry, temperature, and charge balance mechanics of the SJ-RESURF LDMOSFET are examined herein.

A novel imprinted electrochemical sensor based on graphene/carbon nanotubes three-dimensional (3D) nanocomposites modified carbon electrode was developed for the determination of tetrabromobisphenol A. The imprinted film was prepared by one-step electrodeposition technique with pyrrole as the functional monomer and tetrabromobisphenol A as the template molecule. The imprinted sensor was used for the determination of tetrabromobisphenol A with differential pulse voltammetry. A linear relationship between the response currents and the negative logarithm of tetrabromobisphenol A concentrations was obtained in the concentrations range of 1.0×10 −11 –1.0×10 −8 mol L −1 with a detection limit of 3.7×10 −12 mol L −1 (S/N=3). The proposed imprinted sensor showed excellent selectivity towards tetrabromobisphenol A. With good reproducibility and stability, the imprinted electrochemical sensor was used to detect tetrabromobisphenol A in fish samples successfully with the recoveries of 93.3–107.7%.

A novel molecularly imprinted polymer based on magnetic phenyl-modified multi-walled carbon nanotubes was synthesized using curcumin as the template molecule, methacrylic acid as the functional monomer and ethylene glycol dimethacrylate as the cross-linker. The phenyl groups contained in the magnetic imprinted polymers acted as the assisting functional monomer. The magnetic imprinted polymers were characterized by scanning electron microscopy, Fourier-transform infrared spectroscopy and vibrating sample magnetometry. Adsorption studies demonstrated that the magnetic imprinted polymers possessed excellent selectivity toward curcumin with a maximum capacity of 16.80 mg/g. Combining magnetic extraction and high-performance liquid chromatography technology, the magnetic imprinted polymer based on magnetic phenyl-modified multi-walled carbon nanotubes was applied for the rapid separation and enrichment of curcumin from ginger powder and kiwi fruit root successfully.

In this paper, a highly selective sample clean-up procedure combining magnetic dummy molecular imprinting with solid-phase extraction was developed for rapid separation and determination of 4-nonylphenol (NP) in the environmental water samples. The magnetic dummy molecularly imprinted polymers (mag-DMIPs) based on multi-walled carbon nanotubes were successfully synthesized with a surface molecular imprinting technique using 4-tert-octylphenol as the dummy template and tetraethylorthosilicate as the cross-linker. The maximum adsorption capacity of the mag-DMIPs for NP was 52.4 mg g−1 and it took about 20 min to achieve the adsorption equilibrium. The mag-DMIPs exhibited the specific selective adsorption toward NP. Coupled with high performance liquid chromatography analysis, the mag-DMIPs were used to extract solid-phase and detect NP in real water samples successfully with the recoveries of 88.6–98.1%.

Exposure to higher levels of air pollution particulate matter (PM) with an aerodynamic diameter of less than 2.5 μm (PM2.5) links with an increased risk of cardiovascular and respiratory deaths and hospital admission as well as lung cancer. Although the mechanism underlying the correlation between PM2.5 exposure and adverse effects has not fully elucidated, PM2.5-induced oxidative stress has been considered as an important molecular mechanism of PM2.5-mediated toxicity. In this work, human lung epithelial A549 cells were used to further investigate the biological effects of PM2.5 on autophagy. The cell viability showed both time- and concentration-dependent decrease when exposure to PM2.5, which can be attributed to increase of the levels of extracellular lactate dehydrogenase (LDH) release and intracellular reactive oxygen species (ROS) generation in A549 cells. Moreover, PM2.5-induced oxidative damage in A549 cells was observed through the alteration of superoxide dismutase (SOD) and catalase (CAT) activities compared to the unexposed control cells. PM2.5-induced autophagy was indicated by an increase in microtubule-associated protein light chain-3 (LC3) puncta, and accumulation of LC3 in both time- and concentration-dependent manner. PM2.5-induced mRNA expression of autophagy-related protein Atg5 and Beclin1 was also observed compared with those of the unexposed control cells. These results suggest the possibility that PM2.5-induced oxidative stress probably plays a key role in autophagy in A549 cells, which may contribute to PM2.5-induced impairment of pulmonary function.

Bismuth tungstate (Bi2WO6) was synthesized by low-temperature combustion method (LCM) and characterized by diffuse reflectance spectroscope (DRS), X-ray diffraction (XRD), scanning electron microscope (SEM) and Zeta potential. The effects of solution pH and acidity regulator types on the photocatalytic degradation of RhB by LCM-Bi2WO6 were investigated. Results showed that LCM-Bi2WO6 was an orthorhombic crystal and its wavelength of maximum absorption, forbid bandwidth, lattice size and isoelectric point were 455 nm, 2.72 eV, 14.7 nm and 3.43, 536 无 机 材 料 学 报 第 30 卷 respectively. Stronger adsorption and photodegradation of RhB (25 mg/L, pH=4) using LCM-Bi2WO6 as photocatalyst was observed, compared with using TiO2 or Bi2WO6 prepared by hydrothermal method as photocatalyst. Adsorption and photodegradation of RhB by LCM-Bi2WO6 satisfied the pseudo-second-order kinetic equations and first order kinetic equations, respectively. Equilibrated adsorption capacity (7.48-21.93 mg/g) and photodegradation rate constants (0.0197-0.1181 min) of RhB by LCM-Bi2WO6 were positively related to solution pH. Photocatalytic degradation of RhB by LCM-Bi2WO6 was mainly triggered by free hydroxyl groups (•OH). Blue shifts of RhB ultraviolet-visible spectrum indicated its degradation through ethyl removal and conjugated groups break pathway. Weaker adsorption (qe=6.03 mg/g) and photodegradation (kv=0.115 min) of RhB by LCM-Bi2WO6 using H2SO4 as acidity regulator were observed compared with using HCl (qe=21.93 mg/g, kv=0.115 min) as acidity regulator, because of SO4 strong adsorption to LCM-Bi2WO6.

In respect of trench gate power devices, it is difficult to achieve satisfactory gate oxide leakage current, breakdown voltage and reliability characteristics. Trench etching process induced silicon surface damage, convex corner and contamination, which will degrade the silicon dioxide quality. It is convinced that post etching treatment including sacrificial oxidation and chemical dry ashing can improve the gate oxide quality significantly. In this article, we study the treatment of a trench capacitor with sacrificial oxidation and classify the effect of each parameter in the oxidation process. The benefit of N/sub 2/O annealing after gate oxidation will also be discussed. The evaluations of I-V and C-V characteristics are the main considerations of the gate oxide quality in this research.

In this paper a novel composite imprinted material based on poly(methyl methacrylate) (PMMA) coated magnetic multi-walled carbon nanotubes was successfully synthesized using erythromycin as the template and methacrylic acid as the functional monomer. The magnetic carbon nanotube molecularly imprinted polymers (mag-MWCNTs-MIPs) were characterized by transmission electron microscopy (TEM), scanning electron microscopy (SEM), Fourier transform-infrared spectroscopy (FT-IR), X-ray diffraction (XRD) and vibrating sample magnetometery (VSM) in detail. The results showed that a magnetic imprinted layer was coated steadily on the surface of the multi-walled carbon nanotubes. Experiments of adsorption dynamics, static adsorption and selective recognition were conducted to evaluate the adsorption performance. The results showed that the mag-MWCNTs-MIPs displayed rapid dynamic adsorption toward erythromycin, which only needed 30 min to achieve adsorption equilibrium with a maximum adsorption capacity of 31.07 mg g−1. The mag-MWCNTs-MIPs were applied, coupled with high performance liquid chromatography (HPLC), to quickly enrich and detect erythromycin from fish tissue samples with recoveries of 82.7–88.5%. The mag-MWCNTs-MIPs can not only be collected and separated quickly and easily by an external magnet, but also have outstanding mechanical properties and specific recognition toward erythromycin.

A magnetic field enhanced photoelectron ionization (MEPEI) source combined with single photon ionization (SPI) for membrane inlet time-of-flight mass spectrometry was used for on-line detection of ether gasoline additive. Methyl tert-butyl ether (MTBE), ethyl tert-butyl ether (ETBE), methyl tert-amyl ether (TAME) and isopropyl ether (DIPE) were selected as the typical pollutants. A membrane inlet was used to transfer the analytes from liquid into gas phase in an on-line manner by pervaporization without sample pretreatment. Less sample fragments were in SPI, and molecular ions could be used to quick preliminarily qualitative analysis; high energy electrons and fragmentations produced by MEPEI can be used to accurate qualitative isomers and overcame the problem of resolution of overlapping peaks in complex matrix when using direct injection. Under the optimal conditions such as membrane temperature 60 degrees C, membrane thicknesses 50 mu m and membrane areas 160 cm(2), the single sample analysis time was less than 100 s, and the limits of detection for MTBE, ETBE, TAME and DIPE were 5.5, 4.8, 3.3 and 4.3 mu g/L, respectively. The instrument has been successfully applied to rapid analysis of MTBE in simulated water by gasoline.

In this study, traditional bipolar-complementary metal oxide semiconductor (CMOS)-double diffused metal oxide semiconductor (DMOS) (BCD) technology, which is designed for only lateral bipolar (Bipolar, 12 V BVCEO and 25 V BVCBO), complementary metal oxide semiconductor (CMOS, 1.2 V threshold voltage) and double diffused metal oxide semiconductor (DMOS, 40 V breakdown voltage) transistors on the bulk silicon wafer, has been successfully utilized directly in silicon on insulator lateral double diffused metal oxide semiconductor (SOI LDMOS) for the first time without changing any trial parameters. To simultaneously display the characteristics of high-power, high-speed and high-frequency, the results of output characteristics, switch and microwave performance must be moderate instead of optimum. In addition, according to the experimental results, it is proved that Bulk-BCD technology simultaneously enables high-speed, high-frequency and high-blocking-voltage applications–such as those in high-voltage integrated circuit switches (ns-range) and RF power amplifiers (MHz range to GHz range)–using a SOI wafer.