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A novel polymer poly (6-O-MMAGlc) has been synthesized via free radical polymerization of monomer methyl 6-O-methacryloyl-α-D-glucoside (6-O-MMAGlc) and characterized. The influence of poly(6-O-MMAGlc) on the formation of hen egg white lysozyme (HEWL) amyloid fibril was detailly investigated, indicating that the polymer could effectively inhibit the formation of HEWL amyloid fibril. The formation kinetics of HEWL amyloid fibril with the presence of poly(6-O-MMAGlc) was measured by Thioflavin T (ThT) fluorescence method, demonstrating that poly(6-O-MMAGlc) could significantly inhibit the amyloid fibril formation of HEWL in a dose-dependent manner. The inhibitory result was furtherly illustrated by congo red (CR) binding assay, 8-anilino-1-naphthalenesulfonic acid (ANS) fluorescence assay, circular dichroism (CD) spectroscopy and transmission electron microscope (TEM).

Aluminum alloy 6061(Al6061) is one kind of precipitation hardening alloy, and its precipitate generation highly influences the mechanical properties and finished surface quality in diamond cutting. To accurately estimate the surface roughness in diamond turning of Al6061, an improved surface roughness prediction model is proposed in this study with the full consideration of the minimum undeformed chip thickness, the materials plastic side flow, elastic recovery and precipitation effect. Pre-heating treatments and diamond turning experiment are conducted on Al6061 samples to build the relationship between pre-heating conditions, precipitation generation and surface roughness in single point diamond turning (SPDT). The experimental results show that precipitation effects are found on both the deformed chips and the fresh generated surface. The effect of pre-heating conditions on precipitates generation agrees well with its effect on surface roughness of Al6061 in SPDT. Compared with the previously proposed models, the developed model considering the precipitation effect of Al6061 remarkably improves the prediction accuracy by 26 %.

Iron-based porphyrinic metal–organic frameworks (PMOFs) are desirable for biomimetic applications, due to the low toxicity and high abundance of Fe as well as the rich biomimetic functions of metalloporphyrins. Besides, the uniform dispersion of porphyrin centers in PMOFs can effectively protect them from self-dimerization. Nevertheless, it remains a big challenge to synthesize iron-based PMOFs. In this study, a series of Fe–oxo chain-based PMOFs incorporating different metals in porphyrinic centers (namely M-PMOF-3(Fe), M = Fe, Co, Ni, Cu) are synthesized directly from the reaction of metalloporphyrin and iron salts with an improved modulating strategy using a pair of monocarboxylic acids and water as the three-component modulator. The prepared materials of M-PMOF-3(Fe) possess high stability to resist a broad pH range (0–11) and even 2 M HCl in aqueous solutions for 2 days, and their frameworks can be maintained up to 350 °C. Catalytic tests show that M-PMOF-3(Fe) are effective in the aerobic oxidation of C–H bonds using oxygen from the air as the oxidant.

Much of the efficient efforts have been largely devoted to enhancing the CO2 binding affinity in MOFs. In this paper, three isoreticular triazolate frameworks with the formula LIFM-1(TAZ).solvents, LIFM-1(MTAZ).solvents and LIFM-1(AmTAZ).solvents (TAZ = 1,2,4-triazole; MTAZ = 3-methyl-1H-1,2,4-triazole; AmTAZ = 3-amino-1H-1,2,4-triazole) have been prepared by using divalent zinc ions with the ligands of TAZ and its amino and methyl substituted derivatives for comparison of their sorption properties. High thermal stability and phase purity of the three MOFs were verified by thermogravimetric analysis and powder X-ray diffraction, respectively. Single component adsorption isotherms of N2, CO2 and H2 were also measured experimentally. Virial method shows that the porous frameworks of LIFM-1(AmTAZ) display high selectivity of CO2 over N2.

Two rarely phenolic acid-substituted alloses (1, 2) and one new glucoside (3), as well as nine known compounds (4-12) were isolated from rhizomes of Cibotium barometz (L.) J. Sm. Structures of 1-3 were established by extensively spectroscopic analyses (NMR, MS, etc.) and acid hydrolysis. All compounds were evaluated for the hepatoprotective activities against APAP-induced HepG2 cell damage. Compounds 1, 4-7, 10 exhibited significant hepatoprotective activities, even more strongly than positive control, bicycol. In addition, compounds 1 and 9 could reduce PC12 cell death induced by serum deprivation.

It is of significant importance to capture and separate organic pollutants from water sources to combat the growing environmental problems. Advanced sorbent materials with rapid, high-capacity and selective sorption performances are desirable. Herein, a coordination framework (LIFM-WZ-4) containing micro-channels with a large percentage (70%) of “naked” nitrogens is reported, affording donor–acceptor (D–A) interaction abilities with specific selectivity for electron-deficient CO2 gases or cationic dyes. Especially, although with a neutral network, exclusively selective, fast and large adsorption capacities for cationic dyes from aqueous solutions were achieved, with a record high value of 1492.0 mg g−1 for MB+ among the materials reported to date. The underlying adsorption mechanism was probed from both kinetic and thermodynamic considerations, revealing a pseudo-second-order kinetic model and a D–A inducing chemisorption process accounting for the unique selectivity. The saturated sorbent can then be readily recovered by dye release in CH3CN. This easy recyclability provides potential for practical applications in water sanitation and dye separation.

The effect of framework (pore) disorder on gas sorption of azole-based isoreticular Cu(II) MOFs with rtl (rutile) topology and characteristic 1D tubular pore channels is investigated for the first time., Metal–organic frameworks with highly ordered porosity have been studied extensively. In this paper, the effect of framework (pore) disorder on the gas sorption of azole-based isoreticular Cu(II) MOFs with rtl topology and characteristic 1D tubular pore channels is investigated for the first time. In contrast to other isoreticular rtl metal–organic frameworks, the Cu(II) metal–organic framework based on 5-(1H-imidazol-1-yl)isophthalate acid has a crystallographically identifiable disordered framework without open N-donor sites. The framework provides a unique example for investigating the effect of pore disorder on gas sorption that can be systematically evaluated. It exhibits remarkable temperature-dependent hysteretic CO2 sorption up to room temperature, and shows selectivity of CO2 over H2, CH4 and N2 at ambient temperature. The unique property of the framework is its disordered structure featuring distorted 1D tubular channels and DMF-guest-remediated defects. The results imply that structural disorder (defects) may play an important role in the modification of the performance of the material.

Two new furoquinoline alkaloids, named 1'-oxo-isoplatydesmine (1) and demethoxyacrophylline (2), as well as 11 known alkaloids (3-13) were isolated from the root bark of Dictamnus dasycarpus Turcz. The structures of 1 and 2 were established by detailed spectroscopic elucidation, such as 1 D & 2 D NMR and HRMS, etc. The unexpected autoracemization of 1 was discussed based on the stereochemistry of reported dihydrofuroquinolines. Compounds 3–5 exhibited moderate inhibitory activities against Bacillus subtilis, Candida albicans, and Pseudomonas aeruginosa with MICs 32–64 μg/ml, revealing the active principles of D. dasycarpus for treating skin diseases in its traditional usage.

Acetaminophen (N‐acetyl‐para‐aminophenol [APAP]) overdose is the most common cause of drug‐induced liver injury in the Western world and has limited therapeutic options. As an important dietary component intake, fructose is mainly metabolized in liver, but its impact on APAP‐induced liver injury is not well established. We aimed to examine whether fructose supplementation could protect against APAP‐induced hepatotoxicity and to determine potential fructose‐sensitive intracellular mediators. We found that both high‐fructose diet feeding before APAP injection and fructose gavage after APAP injection reduced APAP‐induced liver injury with a concomitant induction of the hepatic carbohydrate‐response element‐binding protein α (ChREBPα)–fibroblast growth factor 21 (FGF21) pathway. In contrast, Chrebpα liver‐specific‐knockout (Chrebpα‐LKO) mice failed to respond to fructose following APAP overdose, suggesting that ChREBPα is the essential intracellular mediator of fructose‐induced hepatoprotective action. Primary mouse hepatocytes with deletion of Fgf21 also failed to show fructose protection against APAP hepatotoxicity. Furthermore, overexpression of FGF21 in the liver was sufficient to reverse liver toxicity in APAP‐injected Chrebpα‐LKO mice. Conclusion: Fructose protects against APAP‐induced hepatotoxicity likely through its ability to activate the hepatocyte ChREBPα–FGF21 axis.

The potential application of curcumin was heavily limited in biomedicine because of its poor solubility in pure water. To circumvent the detracting feature, two novel water-soluble amino acid modified curcumin derivatives (MLC and DLC) have been synthesized through the condensation reaction between curcumin and Nα-Fmoc-Ne-Boc-l-lysine. Benefiting from the enhanced solubility of 3.32×10-2g/mL for MLC and 4.66×10-2g/mL for DLC, the inhibition effects of the as-prepared derivatives on the amyloid fibrillation of lysozyme (HEWL) were investigated detaily in water solution. The obtained results showed that the amyloid fibrillation of HEWL was inhibited to a great extent when the concentrations of MLC and DLC reach to 20.139mM and 49.622mM, respectively. The fluorescence quenching upon the addition of curcumin to HEWL provide a support for static and dynamic recombination quenching process. The binding driving force was assigned to classical hydrophobic interaction between curcumin derivatives and HEWL. In addition, UV-Vis absorption and circular dichroism (CD) spectra confirmed the change of the conformation of HEWL.

The facile preparation of hyperbranched glycopolymers was performed without protecting group chemistry, where the methyl-6-O-methacryloyl-α-D-glucoside (6-O-MMAGlc) monomer was adopted as an AB3*-type inimer. The polymerization was initiated by the hydroxy/cerium(IV) redox process and could be named the self-condensing vinyl copolymerization/redox (SCVP/Redox) process. The oxygen radical (C–O˙), rather than the carbon radical (˙C–OH), was generated by the redox reaction of Ce(IV) with –OH groups on the pyranose in 6-O-MMAGlc, which was confirmed by NMR data. The formation of the branching point and linear chain growth were defined to give the degree of branching (DB). A linear increase of the DB was observed as the concentration of Ce(IV) increased, implying facile control of the DB. More interestingly, the hyperbranched glycopolymers on the amyloid fibrillation of hen egg-white lysozyme (HEWL) exhibited a greater inhibition activity than that of the linear analogue. This substantial study would provide more room to enrich the family of glycopolymers and extend their potential application in biomedicine and biomaterials.

A novel ratiometric fluorescent probe 1, consisting of Boranil derivative as the fluorophore and picolinate as the recognition site for Cu2+, was designed and synthesized. 1 was found to display ratiometric response while interacting with Cu2+ by undergoing a Cu2+-promoted hydrolysis of the picolinate moiety for the release of its precursor, 2. We observed that 1 not only showed quick response time (within 10 min), high sensitivity (detection limit of 0.52 μM), and high selectivity for Cu2+ over other metal ions, but also allowed us to detect Cu2+ in a convenient way of observing fluorescence color change under a 365 nm UV lamp using naked eyes. Our study introduced the first ratiometric fluorescent probe for Cu2+ based on Boranil derivative.

Five previously undescribed hemiterpene glycosides, cibotiumbarosides E-I, and two known hemiterpene glucosides, were isolated from the rhizome of Cibotium barometz (L.) J. Sm. The structures of cibotiumbarosides E-I were established by 1D and 2D NMR spectroscopic analyses and HRMS. The absolute configuration of the aglycone of cibotiumbaroside E was assigned by calculated ECD with the TDDFT method. Cibotiumbarosides F and I both exhibited remarkable hepatoprotective activity against APAP-induced acute liver damage in vitro, which were more effective than the positive control, bicyclol. On the other hand, seven hemiterpene glycosides were all inactive in assays of cytotoxicity, neuroprotection, antidiabetes and anti-inflammation.

The air-dried twigs of Litsea cubeba, a traditional Chinese medicinal tree, afforded 10 new aromatic glycosides (1–10) and 26 known analogues. Their structures were assigned by extensive 1D and 2D NMR experiments, and the absolute configurations were resolved by chemical methods, electronic circular dichroism, specific rotation, and X-ray crystallographic analysis. Compound 4 is the first example of a naturally occurring homoneolignan glucoside. Compounds 4, 6–8, and the known neolignan glucosides (11, 12, and 14) at respective 10 μM concentrations were found to reduce acetaminophen-induced HepG2 cell injury with 30.5–46.0% inhibitions. Furthermore, compounds 12 and 15 demonstrated moderate inhibitory activities against HDAC1, with IC50 values of 3.6 and 4.6 μM, respectively.

C20H28BCl3F4Ru2, triclinic, P1̄ (no. 2), a = 7.7061(15) Å, b = 12.654(3) Å, c = 13.993(3) Å, α = 68.25(3)°, β = 78.71(3)°, γ = 88.89(3)°, V = 1240.8(5) Å3, Z = 2, R gt(F) = 0.0686, wR ref(F 2) = 0.2017, T = 293(2) K.

Hepatic fibrosis is characterized by abnormal accumulation of extracellular matrix (ECM). Hepatic stellate cells (HSCs) are the primary cells that produce ECM in response to hepatic injury, and transforming growth factor-beta (TGF-β) has been regarded as the central stimulus responsible for HSC-mediated ECM production. In the present study, we attempted to identify a critical factor in HSC activation and the underlying mechanism. By analyzing online microarray expression profiles, we found that the expression of high-affinity cationic amino acid transporter 1 (CAT1) was upregulated in hepatic fibrosis models and activated HSCs. We isolated and identified mouse HSCs (MHSCs) and found that in these cells, CAT1 was most highly upregulated by TGF-β1 stimulation in both time- and dose-dependent manners. In vitro, CAT1 overexpression further enhanced, while CAT1 silencing inhibited, the effect of TGF-β1 in promoting MHSC activation. In vivo, CAT1 silencing significantly improved the hepatic fibrosis induced by both CCl4 and non-alcoholic fatty liver disease (NAFLD). In summary, CAT1 was significantly upregulated in TGF-β1-activated MHSCs and mice with hepatic fibrosis. CAT1 silencing inhibited TGF-β1-induced MHSC activation in vitro and fibrogenic changes in vivo. CAT1 is a promising target for hepatic fibrosis treatment that requites further investigation in human cells and clinical practice.

Curcumin is the physiologically and pharmacologically active component of turmeric (Curcuma longa L.) with attractive fluorescent property. However, the applications in live cell imaging field are restricted mainly due to the water-insolubility and cytotoxicity. To overcome this problem, curcumin-incorporated glycopolymers are synthesized by free radical copolymerization in this study. The glycopolymers are well-characterized by infrared spectroscopy (IR), nuclear magnetic resonance (NMR), gel permeation chromatography (GPC), UV-Vis absorption spectroscopy and photoluminescence spectroscopy. Furthermore, obtained glycopolymers are assayed by MTT assay and cell imaging for supporting the potential bio application. The MTT result indicates that the introduction of carbohydrate units can reduce the cytotoxicity of curcumin unit. The live cell imaging investigations reveal that the curcuminincorporated glycopolymers are good candidates for cell imaging and may find broad applications in biological areas such as biological diagnosis, imaging, and detection.

Two novel Boc-L-isoleucine-functionalized curcumin derivatives have been synthesized and characterized, which exhibited enhanced solubility in water compared with the natural curcumin. The solubility could reach 2.12mg/mL for the monosubstituted compound and 3.05mg/mL for the disubstituted compound, respectively. Their anti-amyloidogenic capacity on the model protein, hen egg white lysozyme (HEWL), was examined in aqueous solution. ThT fluorescence assay showed that the operation concentration was only 0.5mM when the inhibition ratio was above 70%. Meanwhile, the inhibitory capacity of monosubstituted curcumin derivative on the formation of HEWL amyloid fibrils was found to be superior to that of disubstituted derivative, suggesting that the phenolic hydroxyl group might contribute to the anti-amyloidogenic activity. Interaction study showed that both curcumin derivatives could bind with HEWL near tryptophan residues and form new ground-state complex before HEWL self-assemblies into amyloid fibrils and thus inhibits the formation of amyloid fibrils. Both of the two cucumin derivatives have displayed low cytotoxicity with HeLa cell.

Gene therapy has shown promise in antitumor strategies for advanced cancer. However, efficient and safe delivery of potent therapeutic gene expressing in specific tumor tissues remains elusive, especially when there exist stromal obstacles. Here we report a non-viral gene delivery approach targeting pancreatic stellate cells (PSCs) as the transfection host in the fibroblast-enriched tumor microenvironment of pancreatic cancer. Plasmid DNA (pDNA) encapsulated in branched polyethylenemine (BPEI) was found to selectively transfect PSCs rather than pancreatic cancer cells and other fibroblast cell lines. Mechanism investigations reveal that the highly expressed fibroblast growth factor receptors (FGFRs) in PSCs facilitated the cellular uptake of polyplexes in PSCs. This delivery platform carrying gene encoding of TNF-related apoptosis-inducing ligand (TRAIL) displayed effective by-stander effect and tumor cell-selective cytotoxicity. More importantly, the therapeutic efficacy was proved in a PSC-enriched orthotopic pancreatic tumor model. Thus, this gene delivery strategy smartly converts PSCs as the microenvironment obstacle for drug delivery into the producer and reservoir of selective tumor-killing proteins.

Alum-processing is a traditional method to attenuate the toxicity of Pinelliae Rhizoma (tubers of Pinellia ternate, PT). The present study aimed at investigating the chemical and cytotoxic changes during alum processing. Metabolomic profiles of raw and alum-processed PT were studied based on ultra-performance liquid chromatography coupled with Orbitrap mass spectrometry. More than 80 chemicals in positive MS mode and 40 chemicals in negative MS mode, such as organic acids, amino acids, glucosides and nucleosides, were identified after multivariate statistical analysis, including principal component analysis and orthogonal partial least-square discriminant analysis. Almost all of the identified chemical markers were significantly decreased ~10- to 100-fold after alum processing. Meanwhile, the correlations between the chemical markers were assimilated to a positive coefficient from disorderly distribution during the processing. Raw PT extracts could inhibit the proliferation of human carcinoma cells (HCT-116, HepG2, and A549) at the rate of 40.5, 24.8 and 31.6% more strongly than processed PT. It was concluded that the alum processing of PT could decrease the number of actively water-soluble principles at the same time as decreasing toxicity. Given the water-insoluble property of toxic calcium oxalate raphides in PT, we suggest that a more scientific processing method should be sought.

The removal of sulfapyridine (SPY) by ferrate(VI) in aqueous solutions under a broad range of reaction conditions, including ferrate(VI) dosage, solution pH, natural organic matter and coexisting inorganic ions, was systematically investigated and the oxidation pathway of SPY by ferrate(VI) was deeply explored. Results showed that 500 µg/L of SPY was efficiently decomposed (86%) within 1 min by 5 mg/L ferrate(VI) at pH 5.6. The increment in ferrate(VI) dosage was surely favorable for SPY removal. The best SPY degradation was achieved at pH 5.6, under or above which the removal decreased. The introduction of inorganic ions in solutions retarded SPY removal. Ten oxidation intermediates were identified and the cleavages of C-S and S-N bonds might be the primary ways of SPY oxidation by ferrate(VI).

Two new 2-(quinonylcarboxamino)benzoates, named aconicarmiquinamides A (1) and B (2), were isolated from an aqueous extract of the lateral roots of Aconitum carmichaelii. Their structures were determined by spectroscopic data analysis, and confirmed by comparison with synthetic methyl 3,6-bis(diethylamino)benzoqunonylcarboxylate (3).

Two new coumarins, 7-(4-hydroxyphenyl)-6H-[1, 3]dioxolo[4,5-g]chromen-6-one (1) and 7-(2-hydroxy-3,4-dimethoxyphenyl)-6H-[1,3]dioxolo[4,5-g]chromen-6-one (2), together with five known coumarins (3–7), were isolated from the roots and stems of flue-cured tobacco (a variety of Nicotiana tabacum L.). Their structures were elucidated by spectroscopic methods, including extensive 1D and 2D NMR techniques. Compounds 1 and 2 were tested for their anti-tobacco mosaic virus (anti-TMV) activity, and they show potential anti-TMV activity with inhibition rates of 14.5 and 31.2%, respectively.

The aim of this study was to investigate the role of miRNA-146a in modulating the function of vascular smooth muscle cells in a rat model of coronary heart disease. Vascular smooth muscle cells were isolated and cultured from the rat coronary heart disease model and normal rats (controls). miRNA-146a levels were measured in vascular smooth muscle cells obtained from rats with coronary heart disease and control rats. The proliferation, growth, apoptosis, and activation of the NF-κB pathway in the vascular smooth muscle cells were detected using the MTT assay and flow cytometry, respectively. The role of the NF-κB pathway in modulating the apoptosis of vascular smooth muscle cells was investigated by measuring the reactivity of the cells to an NF-κB pathway inhibitor (TPCA-1). Vascular smooth muscle cells from the disease model exhibited higher levels of miRNA-146a than that by the normal controls (P = 0.0024). The vascular smooth muscle cells obtained from rats with coronary heart disease showed decreased proliferation and growth and increased apoptosis. miRNA-146a overexpression elevated the rate of cell apoptosis. The NF-κB pathway was activated in vascular smooth muscle cells obtained from rats with coronary heart disease. Inhibition of the NF- κB pathway significantly decreased the rate of vascular smooth muscle cell apoptosis in coronary heart disease rats (P = 0.0038). In conclusion, miRNA- 146a was found to induce vascular smooth muscle cell apoptosis in rats with coronary heart disease via the activation of the NF-κB signal pathway.

A novel thermosensitive and water-soluble fluorescent polymer PNIPAM-Curcumin (P2) containing curcumin unit was synthesized via one-pot method. The chemical structure and optical properties of compounds and polymer were characterized and tested. As the results turned out that P2 displayed excellent water solubility, thermosensitivity and exhibited strong fluorescence emission band in water. Moreover, P2 was further investigated by MTT assay and lives cell imaging with HeLa cells. P2 did not have cytotoxicity in concentration of 200 µg · mL−1 within 48 h and the intracellular fluorescence intensity enhanced with the concentration of P2 varying from 0 to 500 µg · mL−1. According to the experimental results, as a fluorescence probe, P2 synthesized by us not only possesses nice water solubility but also has the advantage of no cytotoxicity, and it can easily enter the cells, which indicates it's a characteristic of high sensitivity and responsiveness. Therefore, P2 will have immense potential to be applied in biomedical fields.

Investigation of an organic extract of the stems of Garcinia bracteata led to the isolation of two new flavones, named bracflavones A (1) and B (2). Their structures were elucidated by spectroscopic evidence. The compounds feature an isopropoxy group at C-3 compared with related known flavonoids isolated from the genus Garcinia. Compounds 1 and 2 were tested for their cytotoxicity. The results revealed that compound 1 showed high cytotoxicity against A549 and PC3 cell lines, and compound 2 showed high cytotoxicity against NB4, A549, SH-SY5Y, PC3, and MCF7 cell lines.

A porous imidazolium polymeric network was synthesized via alkylation of tetrakis-[4-(1H-imidazole-1-yl)phenyl]methane with 1,4-bis(bromomethyl)benzene. Its complexation with palladium yielded a Pd-NHC porous polymeric network, namely Pd-pNHC. Pd-pNHC showed selective uptake of CO2 over N2 due to its polar surface. Pd-pNHC has a BET specific surface area of 308 m2 g−1 and a micropore volume of 0.190 cm3 g−1. Pd-pNHC showed ability to absorb both hydrophilic and aromatic guests (MeOH, EtOH and benzene). Pd(II) catalytically active centers within the porous polymeric network were readily accessible to substrates as demonstrated in Suzuki–Miyaura coupling reactions. High yields were achieved in the coupling reactions of various arylbromides under mild conditions. Additionally, Pd-pNHC catalyzed the reactions in a heterogeneous way and the catalyst could be used for at least ten times without loss of activity.

A simple one-step purification process was provided to extract KGM from KF by phase separation. The results showed that appropriate temperature control was a key factor and the products were inodorous, colourless and of high purity at the optimal temperature 68 °C. In this purification, soluble sugar and starch of extracted KGM were nearly clearly reduced and up to 95%, 80% (T68) of protein and ash were removed, respectively as compared with KF. Odour and transparency were improved 4 ranks and 30%, respectively. Besides, the η app reached 42.30 Pa s and increased by 93.55% as compared, which could stay at a steady level for a week. Furthermore, morphology of extracted KGM displayed regular lamellar and wrinkling distribution for removed impurities. The temperature-controlled method not only enriches the knowledge of KGM purification but also has the potential to broaden the application of KGM.

A BPh2-chelated heterochrysene derivative has been synthesized and characterized. Single crystal analysis of its analogous BF2 complex shows that all carbon and nitrogen atoms are almost in a plane, while the boron atoms twist out of this plane with a torsion angle of 28.796° measured between plane OBN and plane C1–C4–C4′. The BPh2 and BF2 compounds emit strong yellow and green light in methylene chloride with high fluorescence quantum yields, respectively. Thermogravimetric analysis results indicate that the thermal stability of both compounds is high. In addition, a photoswitching device was fabricated based on a thin film of the BF2 complex spin-coated onto single-walled carbon nanotubes, which produces a steady and reproducible photocurrent response.

Crayfish carapace powder is a low cost natural absorbent effective for the removal of heavy metals. Its adsorption capacity was far superior to its extracts—namely, chitin and chitosan. To understand the mechanism of heavy metals removed by this material, various techniques were implemented to characterize the samples. Scanning electron microscopy and X-ray diffraction analysis showed there was metal carbonate crystal formed on the surface of carapace granules after adsorbing heavy metal ions. The ion exchange between Ca2+ and M2+, chelation between M2+ and chitin, protein, chemical precipitation, and physical adsorption may be the external mechanism of adsorption.

Konjac glucomannan (KGM), mainly contained in konjac flour (KF), has been widely applied in food industry. However, commercial KF is usually light-colored with low KGM content, fish-like smell and low viscosity. In this paper, a one-step procedure, azeotropy-assisted acidic ethanol, was explored to elevate the overall quality of KF. Composition, transparency, color and odor evaluation, rheological properties and morphology of all the disposed KF were measured to evaluate the quality as compared with commercial KF. KF with 90% (w/w) KGM content could be easily obtained by pH regulation. At the high pH level (4.5–5.5), the quality of disposed KF was greatly improved, included by purity, transparency, and odor evaluation. Both the rheological properties and morphology observation verified the elevated effect. But the quality of KF was inclined to be poor at low pH level (2.5–4.0) due to KGM hydrolysis. The obtained white-colored Y4.5 with light fish smell tended to possess the highest viscosity and stability. The results illustrated washing by acidic ethanol at azeotropy point was feasible to effectively improve the quality of KF. The method has not only broadened KF potential application in food field, but also enriched the knowledge of its quality elevation.

The novel hyperbranced polymers containing reductive groups were successfully prepared and characterized using redox/reversible addition fragmentation chain transfer (RAFT)/self-condensing vinyl polymerization (SCVP) method. Several redox initiating chemicals such as Cu(III)/-CONH2, Ce(IV)/-CONH2 and Ce(IV)/-OH were chosen to increase the free radical generating rate, and the chain transfer agent (CTA) was used to reduce the molecular chain propagating rate, in order to obtain polymers with high degree of branching. Detailed analyses based on the molecular weight, α value and the degree of branching of polymers (DB) obtained from 1H-NMR spectra and multi detector size exclusion chromatography (MDSEC) suggested the acquiring of hyperbranced polyacrylamides with Cu(III)/-CONH2 and Ce(IV)/-CONH2 as initiator in the presence of the CTA. Meanwhile, the as-prepared poly(N-hydroxymethyl acrylamide) (PNHAM) with higher DB value (0.48) proved that using Ce(IV)/-OH as the initiator could increase the free radical generating rate and diminish the gap between the propagating rate and the initiation rate during the reaction procedure. In addition, the effect of oxidant concentration on the Mark-Houwink index (α) value and the DB was also studied.

In this paper, an approach to improve several konjac flour (KF) qualities by dimethyl sulfoxide (DMSO) addition using various concentrations at different temperature levels was proposed. Also, various properties of native and refined KF, including transparency, chemical composition and rheological properties have been investigated. The results showed that the KF refined by 75% DMSO achieved 27.7% improvement in transparency, 99.7% removal of starch, 99.4% removal of soluble sugar, and 98.2% removal of protein as well as more satisfactory viscosity stability. In addition, the morphology structure of refined KF showed a significant difference compared with the native one as observed using the SEM, which is promising for further industrial application. Furthermore, the rheological properties of both native and refined konjac sols were studied and the results showed that DMSO refinement is an effective and alternative approach to improve the qualities of KF in many aspects.

C10H7FN2O5, monoclinic, P21/n (no. 14), a = 8.5781(17) Å, b = 5.3121(11) Å, c = 23.578(5) Å, β = 96.68(3)°, V = 1067.1(4) Å3, Z = 4, R gt(F) = 0.0375, wR ref(F 2) = 0.1138, T = 293(2) K.

A novel indigo derivative ( 1 ) was synthesized and fully characterized. Its structure, confirmed by X-ray crystallography, showed that compound 1 is a planar molecule. Interestingly, compound 1 only has response to fluoride ions among six different anions (F − , Cl − , Br − , I − , AcO − , and HSO 4 − ) in an anhydrous methylene chloride solution and this response can be detected by the ‘naked eyes’.

Nine new homosecoiridoid alkaloids, named lonijaposides O-W (1-9), along with 19 known compounds, were isolated from an aqueous extract of the flower buds of Lonicera japonica. Their structures and absolute configurations were determined by spectroscopic data analysis and chemical methods. Lonijaposides O-W have structural features that involve amino acid units sharing the N atom with a pyridinium (1-5) or nicotinic acid (6-9) moiety. The absolute configurations of the amino acid units were determined by oxidation of each pyridinium ring moiety with potassium ferricyanide, hydrolysis of the oxidation product, and Marfey's analysis of the hydrolysate. This procedure was validated by oxidizing and hydrolyzing synthetic model compounds. The phenylalanine units in compounds 4, 5, and 9 have the d-configuration, and the other amino acid units in 1-3 and 6-8 possess the l-configuration. Compounds 1, 4, 6, and 9 and the known compounds 3,4-di-O-caffeoylquinic acid, 3,5-di-O-caffeoylquinic acid, and 5'-O-methyladenosine exhibited antiviral activity against the influenza virus A/Hanfang/359/95 (H3N2) with IC50 values of 3.4-11.6 μM, and 4 inhibited Coxsackie virus B3 replication with an IC50 value of 12.3 μM.

In this paper, we have developed a simple method to prepare transparent composite fluorescent films by using poly(acrylic acid) co-polymer as a matrix and QDs–polystyrene fluorescent microspheres as light-emitting materials. The strategies include encapsulating fluorescent hydrophobic QDs into polystyrene microspheres with a miniemulsion polymerization process and fabricating composite fluorescent films with a coating method. The obtained light-emitting films were transparent under visible region and showed bright red, green, and blue lights under the irradiation of UV light. The PL intensity of the composite films shows linear increase when the concentration of QDs–polystyrene microspheres is increased within a certain range. Moreover, a white light-emitting film can be obtained by combination of red, green, and blue QDs–polystyrene microspheres with a correct proportion.

This paper describes a robust ligand exchange approach for preparing biocompatible CdSe/ZnS quantum dots (QDs) to make bioprobe for effective cell imaging. In this method, polymaleic anhydride (PMA) ligand are first used to replace original hydrophobic ligand (oleic acid) and form a protection shell with multiple hydrophilic groups to coat and protect CdSe/ZnS QDs. The as-prepared aqueous QDs exhibit small particle size, good colloidal stability in aqueous solutions with a wide range of pH, salt concentrations and under thermal treatment, which are necessary for biological applications. The use of this new class of aqueous QDs for effective cell imaging shows strong fluorescence signal to human embryonic stem cell, which demonstrate that PMA coated QDs are fully satisfied with the requirements of preparing high quality biological probe.

Six new glycosides (1-6) have been isolated from the flower buds of Lonicera japonica. Their structures including the absolute configurations were determined by spectroscopic and chemical methods as ( - )-2-hydroxy-5-methoxybenzoic acid 2-O-β-d-(6-O-benzoyl)-glucopyranoside (1), ( - )-4-hydroxy-3,5-dimethoxybenzoic acid 4-O-β-d-(6-O-benzoyl)-glucopyranoside (2), ( - )-(E)-3,5-dimethoxyphenylpropenoic acid 4-O-β-d-(6-O-benzoyl)-glucopyranoside (3), ( - )-(7S,8R)-(4-hydroxyphenylglycerol 9-O-β-d-[6-O-(E)-4-hydroxy-3,5-dimethoxyphenylpropenoyl]-glucopyranoside (4), ( - )-(7S,8R)-(4-hydroxy-3-methoxyphenylglycerol 9-O-β-d-[6-O-(E)-4-hydroxy-3,5-dimethoxyphenylpropenoyl]-glucopyranoside (5), and ( - )-4-hydroxy-3-methoxyphenol β-d-{6-O-[4-O-(7S,8R)-(4-hydroxy-3-methoxyphenylglycerol-8-yl)-3-methoxybenzoyl]}-glucopyranoside (6), respectively.

The geometric structures, relative stabilities, growth patterns, and electronic properties of pure and Rb 2 -substituted Au n +2 ( n = 1–10) clusters are investigated by using the density functional theory within generalized gradient approximation in conjunction with a valence electron basis set. The stable geometries with different spin multiplicities are determined. The results show that doping gold clusters with two Rb atoms dramatically affects the ground-state geometries of the pure gold clusters, the doped Rb atoms prefer locating on the surface and mirror symmetry positions, and the Au-capped Rb 2 Au n –1 clusters are the dominant growth pattern. The ground-state structures of Rb 2 Au n ( n ⩾ 3) clusters tend to be considered as three dimensional configurations with a two dimensional (or only slightly tilted) gold subunits motif. The energetic and electronic properties of the Rb 2 Au n and Au n +2 ( n = 1–10) clusters are strongly dependent on sizes and structures. The average atomic binding energies show that the doped Rb atoms enhance the stabilities of host clusters for the larger clusters ( n > 5). Dramatic odd–even alternative behaviors are found in the fragmentation energies, the second-finite difference of energies, the HOMO–LUMO gaps, VIPs, and chemical hardness for both Rb 2 Au n and Au n +2 ( n = 1–10) clusters. In addition, it is found that Rb 2 Au 6 isomer is the most stable of the Rb 2 Au n ( n = 1–10) clusters.

This paper presents a theoretical and experimental investigation into the effect of the workpiece material on surface roughness in the ultra-precision milling process. The influences of material swelling and tool-tip vibration on surface generation in ultra-precision raster milling are studied. A new method is proposed to characterize material-induced surface roughness on the raster-milled surface. A new parameter is defined to characterize the extent of surface roughness profile distortion induced by the materials being cut. An experiment is conducted to compare the proposed method with surface roughness parameters and power spectrum density analysis method by machining three different workpiece materials. The results show that the presence of elastic recovery improves the surface finish in ultra-precision raster milling and that, among the three materials being cut in the experiment, aluminum bronze has the greatest influence on surface finish due to its highest elastic recovery rate and hardness. The results also show that, in the case of faster feed rates, the proposed method more efficiently characterizes material-induced surface roughness.

Two new phenylpropanoids(1 and 2), together with thirteen known compounds(3-15), have been isolated from the root of Paeonia lactiflora by using various chromatographic techniques. Their structures were identified by spectroscopic data analysis(MS,IR,1D and 2D NMR)as(+)-(7R,8R)-1-guaiacyl-1,2-propanediolacetonide(1),(-)-(7R,8S)-1-guaiacyl-1,2-propanediolacetonide(2),O-senecioyllomatin(3),O-angeloyllomatin(4),(+)-cis-3'-senecioyloxy-4'-angeloyloxy-3',4'-dihydroseselin(5),columbianadin(6), benzyl 2,5-dihydroxybenzoate(7),3,6-dimethyl-5-hydroxyBenzo-furan(8),(S)-evofolin-A(9),2,3-dihydroxy-4-methoxyacetophenone(10), 2,5-dihydroxy-4-methoxyacetophenone(11), 2,5-dihydroxy-4-methyl acetophenone(12),ethyl 4-hydroxybenzoate(13), vanillic acid(14),and 4-hydroxy-3-methoxybenzaldehyde(15).Compounds 1 and 2 were new compounds,and compounds 3-9 were obtained from the genus Paeonia for the first time.

Published online: December 28, 2015 (DOI: 10.4238/2015.December.28.19). Corrected after publication: June 24, 2016 (DOI: 10.4238/gmr.150267961). There is a change in the corresponding author, who should be Y.F. Liu.

Curcumin is a potential natural anticancer drug with low oral bioavailability because of poor water solubility. The aqueous solubility of curcumin is enhanced by means of modification with the carbohydrate units. Polymerization of the curcumin-containing monomer with carbohydrate-containing monomer gives the water-soluble glycopolymer bearing curcumin pendant residues. The obtained copolymers (P1 and P2) having desirable water solubility were well-characterized by infrared spectroscopy (IR), nuclear magnetic resonance (NMR), gel permeation chromatography (GPC), UV–Vis absorption spectroscopy, and photoluminescence spectroscopy. The copolymer P2 with a molar ratio of 1:6 (curcumin/carbohydrate) calculated from the proton NMR results exhibits a similar anticancer activity compared to original curcumin, which may serve as a potential chemotherapeutic agent in the field of anticancer medicine. The prepared glycopolymer (P2) bearing curcumin residues exhibit a similar anticancer activity to original curcumin.

This article presents theoretical and experimental investigations into the effect of the workpiece material on surface roughness in ultraprecision raster milling (UPRM). The influence of material elastic recovery on chip thickness and surface generation in UPRM is studied. A holistic surface roughness prediction model is developed by considering the influences of cutting parameters, tool geometry and the material elastic recovery on surface generation. The experimental results show that the proposed surface roughness prediction model makes a more precise prediction by adding the elastic recovery rate as a material factor, and the presence of elastic recovery improves the surface finishing of the raster milled surface. The material effect on surface roughness decreases with the increasing of feed rate. The precipitates in the machining of aluminum alloy 6061 result in the generation of imperfection on the raster milled surface. The machining of aluminum bronze has the greatest influence on surface roughnes...

Eight new 9,10-anthraquinones (1–8) including three acetonide derivatives of 3-hydroxy-2-hydroxymethyl-9,10-anthraquinones (6–8) were isolated from an ethanol extract of the roots of Knoxia valerianoides. On the basis of chemical transformation reactions of the co-occurring 14 and 15 combined with HPLC–DAD–ESI–MS analysis of the extracts, the previously and newly isolated 2-methoxymethyl- and 2-ethoxymethyl-9,10-anthraquinones (4, 5, and 9–13), as well as the 3-hydroxy-2-hydroxymethyl-9,10-anthraquinone acetonide derivatives (6–8), were shown to be solvolytic artifacts. In the in vitro assays, compound 4 was active to protect hepatocyte (WB-F344) damage.