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Polysaccharides have hypoglycemic activity and pea protein has high nutritional value. The purified pea glycoprotein PGP2 has been shown to inhibit the activity of α-glucosidase and α-amylase in previous studies. To study the mechanism of PGP2-induced blood glucose lowering in vivo, this paper established a diabetic mouse model by intraperitoneal injection of STZ and high-fat diet, and evaluated the blood-glucose-lowering activity of the pea component PGP2 at different doses. The results showed that intragastric administration of PGP2 could effectively reduce diabetic weight loss and polyphagia symptoms, reduce fasting blood glucose levels in mice, and improve oral glucose tolerance levels in mice. PGP2 could promote insulin secretion and had a protective effect on mouse organs. After intragastric administration of PGP2 in mice, the serum levels of total cholesterol, triglycerides and low-density lipoprotein decreased. PGP2 up-regulated the gene expression of insulin receptor substrates IRS-1 and IRS-2 in liver tissues, thereby reducing insulin resistance. Based on the above experimental results, PGP2 had good hypoglycemic activity and was expected to be developed as a natural medicine for the treatment of type II diabetes.

Natural biological macromolecules with putative functions of gut microbiota regulation possess the advantage of improving metabolic syndrome (MS). In this research, we aimed to determine the effects of Flammulina velutipes polysaccharide (FVP) (Expt. 1) and fecal microbiota transplantation (FMT) (Expt. 2) on MS-related disorders, gut microbiota structure changes and their underlying mechanisms in a murine model fed with high-fat diet (HFD). In Expt. 1, six-week-old male C57BL/6J mice were fed with a control diet (10% calories from fat) or a high fat diet (45% calories from fat), administered with saline or FVP (0.4 mg per g b.w.) by gavage over a 12-week period. In Expt. 2, mice were fed with a HFD, administered with fecal supernatants from healthy and FVP-fed donor mice for 12 weeks simultaneously. The body mass, blood lipid levels and blood glucose homeostasis of mice were analyzed, and total RNA from mouse liver and adipose tissue were extracted by TRIzol and the lipid metabolism-related gene expressions were calculated by qRT-PCR. Gut microbiota changes were evaluated by high-throughput sequencing. Results indicated that FVP and FMT supplementations showed an attenuation effect on mouse obesity, hyperlipidemia and insulin resistance. Up-regulated expressions of Ampkα1 and Ppara were found both in FVP and FMT treatment groups. Different changes were found in the gut microbiota caused by FVP and FMT, respectively. PICRUSt analysis indicated that compared with FVP supplementation, FMT showed a significant effect on regulating lipid metabolism in HFD-fed mice. The findings from this study indicated that oral administrations of FVP or FMT could significantly attenuate MS-related obesity, hyperlipidemia and insulin resistance in HFD-fed mice, and the beneficial effects may be mediated through lipid metabolism and gut microbiota regulation in different ways. These results improve the understanding of the functional activity of FVP as prebiotics.

Besides the activation of CO2 by Lewis basic groups, the synergistic effects of Lewis acid sites (or hydrogen bond donor) together with halogen nucleophilic anions to activate epoxide ring opening were also important steps to develop an efficient catalyst for the cycloaddition reaction of CO2 and epoxides. Herein, an aminoethylimidazole IL-modified MOF catalyst with multiple catalytic active sites (denoted as MIL-101-NHIM-NH2) was synthesized through an aldimine condensation post-synthesis method. Through thorough characterizations, such as FT-IR, XRD, SEM-EDS mappings, N2 adsorption and desorption, XPS, elemental analysis and TG measurement, the results showed that the surface of MIL-101-NHIM-NH2 was successfully grafted with the ionic liquid. Owing to the synergistic effects of multiple active sites containing Cr, –NH2 and Br− in the MIL-101-NHIM-NH2 catalyst, MIL-101-NHIM-NH2 could efficiently catalyze the cycloaddition reaction of CO2 and epoxide without additional solvent and cocatalyst; 93.5% of propylene carbonate was obtained at 120 °C, 2 MPa and 4 h. Moreover, MIL-101-NHIM-NH2 also showed better recycling stability within five catalytic runs and easy separation in the CO2 cycloaddition reaction.

Edible mushrooms are rich sources of bioactive components. In this study, a polyphenol-rich extract, designated as PPEP, was isolated from an edible mushroom, Pleurotus eryngii. Using ultra high performance liquid chromatograph combined with triple time-of-flight mass spectrometry (UPLC-TOF/MS/MS), gallic acid monohydrate, 3-(3,4-dihydroxyphenyl)-propionic acid, methyl gallate, syringic acid, ellagic acid and catechin were identified in PPEP. This phenolic-rich extract PPEP exhibited anti-inflammatory effect in lipopolysaccharide-stimulated RAW264.7 macrophages by inhibiting the overproduction of pro-inflammatory mediators including nitric oxide (NO) and reactive oxygen species (ROS). It was demonstrated that the anti-inflammatory effects of PPEP were associated with the inhibition of iNOS expression, suppression of p-IκB protein expression and inhibition of NF-κB and IκB mRNA expression. Next, the inhibitory effect of PPEP against human colon cancer cells was also determined. PPEP suppressed cell proliferation of human colon cancer HCT116 cells in a dose- and time-dependent fashion, while it showed no inhibitory effect on normal human colonic myofibroblasts CCD-18Co cells at the same tested concentrations (0-200 μg mL-1). Moreover, PPEP induced cell cycle arrest and led to extensive cellular apoptosis in human colon cancer cells, which was associated with the downregulation of cell cycle-related signaling protein, e.g. cyclin B and cyclin E, and the upregulation of apoptosis-related signaling protein caspase-3 and cleaved caspase-3. Overall, our results provided a basis for using PPEP as a promising preventive agent against inflammatory disease and colon cancer.

Magnetic Fe3O4@Au nanoparticles (NPs) were fabricated using a specific strategy for use as a surface-enhanced Raman scattering (SERS) substrate. The Raman enhancement of Fe3O4@Au NPs could be verified by the detection of rhodamine and crystal violet. The resonator plasma of gold nanoparticles could significantly improve the SERS activity of Fe3O4 magnetic nanoparticles. The results showed that the fabricated Fe3O4@Au NPs have superior SERS sensitivity for rhodamine and crystal violet with a detection limit of 10−7 M. Moreover, the magnetic properties of Fe3O4 are conducive for easily separating Fe3O4@Au NPs from solution. Due to the convenience of operating and high efficiency technique for separating the product, the Fe3O4@Au NPs could be further developed for other applications.

Cetyltrimethyl ammonium bromide and benzylideneacetone are used as electrolyte additives respectively for inhibiting hydrogen evolution on electrochemically active carbon and prolonging the cycle life of valve-regulated lead-acid batteries working under high-rate partial-state-of-charge conditions. It has been found that the addition of cetyltrimethyl ammonium bromide or benzylideneacetone in H2SO4 electrolyte can effectively increase the overpotential of hydrogen evolution and decrease the evolution rate of hydrogen on electrochemically active carbon. An appropriate addition amount of cetyltrimethyl ammonium bromide or benzylideneacetone in the H2SO4 electrolyte of batteries can remarkably slow down the evolution rate of hydrogen on the negative plates, decrease the cut-off charging voltage, and increase the cut-off discharging voltage. Furthermore, the presence of cetyltrimethyl ammonium bromide or benzylideneacetone prolongs the cycle life of valve-regulated lead-acid batteries under high-rate partial-state-of-charge conditions. In comparison with cetyltrimethyl ammonium bromide at the concentration of 240 mg L−1, benzylideneacetone at the concentration of 20 mg L−1 shows better performances in terms of the improved cycle life of the batteries.

Circadian rhythms may influence the pharmacokinetics of drugs. This study aimed to investigate the pharmacokinetic characteristics of gefitinib at different dosing times and the underlying mechanisms. The Balb/c nude mice were housed under a constant 12 h light/dark cycle (lights period 7:00 to 19:00) with food and water available ad libitum. The tumor-bearing nude mice model was established and all the mice were randomly divided into six groups and gavaged with gefitinib. The plasma and liver tissues were obtained for pharmacokinetics analysis and used to examine the mRNA expression of metabolic enzymes and its upstream signal. AUC(0–24 h) and MRT(0–24 h) of 1 h and 17 h after light onset (HALO) gefitinib groups were higher. Clearance (CL) in 1 and 17 HALO gefitinib groups were lower and the highest was found in 9 and 13 HALO gefitinib groups. The mRNA expressions of Cyp3a11, Cyp3a13, pregnenolone X receptor (PXR), constitutive androstane receptor (CAR) and brain and muscle ARNT-like-1 (Bmal1) were higher during the late light phase and the early dark phase, while the mRNA expressions of period 1 (Per 1) and period 2 (Per 2) were lower in the same time. These results show that the pharmacokinetic characteristics of gefitinib have significant circadian rhythms, which may be correlated with rhythmic expressions of metabolic enzymes and their upstream signal. This study may provide experimental evidences for clinical pharmacological research.

A highly ordered mesoporous silica material (SBA-15) functionalized with 5-(4-carboxy-phenylazo)-8-hydroxyquinoline (CPA-8-HQL) for use as a fluorescence chemosensor for Pb2+ detection has been reported in this study. XRD, TEM, FT-IR, UV-vis diffuse reflectance spectra and TGA were used to characterize the grafting process. The results proved that CPA-8-HQL was successfully anchored into the channel of SBA-15 and that the primary ordered mesoporous structure of SBA-15 was well preserved. A fluorescence spectrophotometer was utilized to investigate the sensing properties, and a highly fluorescent enhancement at 429 nm was observed in the presence of Pb2+. Measurements of the sensitivity parameters demonstrated that the obtained organic/inorganic hybrid possessed excellent sensitivity and selectivity to Pb2+ in aqueous media. The lowest limit of detection was 4.90 × 10−7 mol L−1 for Pb2+.

Three new supramolecular architectures based on polyoxovanadates H6V10O28·2HMTA·8H2O(1), [Ni(enMe)3]2(VIV8VV7O36Cl)·2H3O (2) and [Co(en)3]2(VIV8VV7O36Cl)·2H3O (3) (HMTA = hexamethylenetetramine, enMe = 1,2′-propanediamine and en = ethylenediamine) have been prepared and characterized by elemental analyses, IR spectra, XPS spectra and single crystal X-ray diffraction structure analyses. Compound 1 displays a 3-D (4,8)-connected supramolecular host network, which is constructed of octamer water clusters and HMTA molecules, with 1-D channels occupied by the template [H6V10O28] units. Compound 2 possesses a 2-D (3,6)-connected supramolecular layered structure formed by water molecules and [V15O36]3− units showing honeycomb cavities occupied by the transition metal complexes (TMCs). Compound 3 exhibits a 3-D (4,6)-connected supramolecular host network built by the [V15O36]3− units and the lattice water molecules with TMCs cations as the template. By a careful inspection of the structures of 1–3, it is believed that the steric hindrances of organonitrogen ligands are important for the formation of different supramolecular networks. Compound 1 exhibits intensive photoluminescence and compound 3 displays antiferromagnetic interactions.

Four inorganic–organic hybrid materials based on poly(oxomolybdophosphate) cluster building blocks have been obtained by hydrothermal methods. 1 shows a 2-D sheet structure, 2 and 3 possess 1-D chain structures and 4 is the discrete cluster. Crystal structural analysis reveals that the dimensionality and organization of those compounds can be tuned by the pH value of the reaction system. In addition, the fluorescence emissions are analysed of compounds 1, 2 and 4 containing Cd atoms with d10 electronic configuration red-shift along with the increase in the dimensions of those compounds.

The dispersion capacity of MoO3 on the surface of muscovite powder was studied by X-ray photoelectron spectroscopy (XPS) and X-ray diffraction (XRD) techniques. The results indicated that MoO3 can disperse onto the surface of a support as a sub-monolayer. The dispersion capacity was 5.88 mg MoO3 (g muscovite)−1, or 3.24 Mo atoms nm−2. The diffusing process of MoO3 on muscovite wafer was investigated by means of Synchrotron Radiation excited Total-reflection X-Ray Fluorescence spectroscopy (SR-TXRF). A stripe of MoO3 on the muscovite wafer was used as the diffusion source. After thermal treatment in air or dry N2, MoO3 diffuses onto the surface of muscovite and forms a sub-monolayer. Sublimation of MoO3 was also detected during the diffusion process. The diffusion rate in two heating atmospheres differed significantly. The diffusion rate of MoO3 on muscovite in dry N2 was greater than that in air. A possible explanation of the phenomena is that surface diffusion onto the muscovite surface plays a more important role in the process than transportation via gas phase during the diffusion of MoO3.

Electrodeposited Au–Pt alloy nanoparticles supported on ITO-glass substrates have been used as a model catalyst to study the electro-oxidation of methanol (0.5 M) in a KOH (0.5 M) electrolyte. Using cyclic voltammetry, we show that the Au–Pt alloy nanoparticles exhibit a significantly higher catalytic activity than the Pt nanoparticles, while the Au nanoparticles show no catalytic affinity toward electro-oxidation of methanol. The Au–Pt alloy nanoparticles are also found to be catalytically more reactive than bimetallic Au-core Pt-shell and Pt-core Au-shell nanoparticles. We further show that these Au–Pt alloy nanoparticles working in alkaline solution could act as an amperometric sensor for the determination of alcohol concentration. The exceptional performance of this nanoalloy sensor, including its short response time (2 s), relatively large linear range (1–11 mM), low detection limit (0.1 mM), high sensitivity (0.043 mA cm−2 mM−1) and long-term stability (over 90 days), are also characterized. The present nanoalloy sensor also has the lowest working potential (0.25 V), making it less prone to an interference effect.

Conducting polymer poly(3,4-ethylenedioxythiophene):polystyrenesulfonate (PEDOT:PSS) is gaining technological importance for the fabrication of organic and organic–inorganic heterostructure devices. The conductivity of PEDOT:PSS can be improved by the addition of co-solvents. Here, we show that the simple addition of a suitable wt% of a co-solvent, either ethylene glycol (EG) or dimethyl sulfoxide (DMSO), in PEDOT:PSS can significantly enhance the performance of hybrid solar cells. We provide a morphological model to explain the influence of the co-solvents in PEDOT:PSS, in which the co-solvent modifies the internal crystalline ordering of individual PEDOT nanocrystals that increases the crystal size and forms closely packed nanocrystals, and it also facilitates rearrangement of PSS that reduces its surface chain networks to enhance the polymer conductivity and hybrid solar cell properties. A hybrid solar cell made of EG 7 wt% modified PEDOT:PSS on planar Si exhibits an exceptionally high power conversion efficiency exceeding 12% for the first time.

The protein N-terminal sequence is essential for protein identification and confirmation of the removal of N-terminal methionine or signal peptides. Without special labeling, it is difficult to distinguish the protein N-terminus from lots of peptides derived by enzymatic digestion by mass spectrometry (MS). Here, a robust method based on specific d0/d3-acetylation of the protein N-terminal amino group and selective monitoring of the doublet acetylated peptide was introduced. After the protein was guanidinated, it was acetylated by a 1:1 mixture of acetic anhydride-d0 and acetic anhydride-d6, the derivatized protein was trypsin-digested, and monitored by matrix-assisted laser desorption/ionization (MALDI) MS. Only the amino group of the protein N-terminal peptide would be tagged by one unique d0/d3-acetyl group, which appeared as a pair of characteristic isotopic peaks with a mass difference of 3 Da in the profile of peptide mass fingerprinting (PMF), whilst other internal peptides did not have such a characteristic isotopic pattern. In the next step, the recognized N-terminal peptide could be selected as a precursor ion for tandem mass spectrometric (MS/MS) analysis. Four proteins were successfully tested by this method and all N-terminal peptides were specially assigned. The results indicate the potential usage of this method in protein N-terminal identification.