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Iron difluoride (FeF2) is considered a high-capacity cathode material for lithium-ion batteries. However, its specific capacity and stability are limited by the poor electrochemical kinetics of conversion reactions. Herein, the conversion reaction is confined in a localized nanosized space by encapsulating FeF2 nanoparticles in polymer gelatin. The FeF2 nanocrystal-coated polyvinylidene fluoride-based layer (defined as FeF2@100%G-40%P) was synthesized by glucose-assisted in-situ gelatinization to construct an artificial cathode solid electrolyte interphase via a solvothermal process. Thanks to the improved kinetics of the localized conversion reaction, the obtained FeF2@100%G-40%P electrodes show good cyclic stability (313 mA h g−1 after 150 cycles at 100 mA g−1, corresponding to a retention of 80%) and a high rate performance (186.6 mA h g−1 at 500 mA g−1).

Based on hydrophilic interaction liquid chromatography (HILIC) liquid chromatography-mass spectrometry (LC-MS), untargeted differential metabolomics analysis was performed on the pear wine samples before and after browning to determine the key compounds that affect the browning of Dangshan pear wine. A total of 196 significantly differential metabolites were found, 22 of which might be related to the browning of Dangshan pear wine. d-(+)-glucose, l-phenylalanine, l-norleucine, methionine, d-(+)-proline, aloin, and rutin were the key differential metabolites in pear wine before and after browning. The Maillard reaction of d-(+)-glucose, l-norleucine, methionine, and the oxidation of aloin played critical roles in the browning of Dangshan pear wine. The reaction of aloin and glucose to form 5-hydroxyaloin A, 7-hydroxyaloin B, and elgonica-dimer A was one of the important metabolic pathways in which the phenolic compounds formed anthraquinone during the browning process of Dangshan pear wine.

Metal organic frameworks (MOFs) have exhibited potential for application as heterogeneous catalytic materials because they consist of empty space, which can be used for encapsulation. Encapsulation of H3PW12O40 (HPW) in MOFs, such as the fabrication of MIL-101, by direct synthesis method or impregnation has drawn significant interest. However, few researches have used MOFs as catalysts for acetalization. This study evaluates the use of HPW encapsulated in MIL-101(Cr) to make it a catalyst in the acetalization of vanillin propylene glycol. Samples fabricated using various techniques (encapsulation and impregnation) were characterized by SEM, TEM, N2 adsorption–desorption, XRD, and FT-IR. The synthesis conditions of HPW@MIL-101 and their effects on vanillin conversion were examined. The reaction kinetics was also investigated under optimal conditions. Vanillin conversion showed that introducing HPW directly into MIL-101(Cr) during synthesis induced a 14% increase, compared with impregnation. The results indicated that HPW@MIL-101(Cr) is an effective method for vanillin propylene glycol acetal production and is reusable.

Ethyl carbamate (EC) is a potential carcinogen to humans that is mainly produced through the spontaneous reaction between urea and ethanol during Chinese rice wine brewing. We metabolically engineered a strain by over-expressing the DUR3 gene in a previously modified strain using an improved CRISPR/Cas9 system to further decrease the EC level. Homologous recombination of the DUR3 over-expression cassette was performed at the HO locus by individual transformation of the constructed plasmid CRISPR-DUR3-gBlock-HO, generating the engineered strain N85DUR1,2/DUR3-c. Consequently, the DUR3 expression level was significantly enhanced in the modified strain, resulting in increased utilization of urea. The brewing test showed that N85DUR1,2/DUR3-c reduced urea and EC concentrations by 92.0% and 58.5%, respectively, compared with those of the original N85 strain. Moreover, the engineered strain showed good genetic stability in reducing urea content during the repeated brewing experiments. Importantly, the genetic manipulation had a negligible effect on the growth and fermentation characteristics of the yeast strain. Therefore, the constructed strain is potentially suitable for application to reduce urea and EC contents during production of Chinese rice wine. KEY POINTS: • An efficient CRISPR vector was constructed and applied for DUR3 over-expression. • Multi-modification of urea cycle had synergistic effect on reducing EC level. • Fermentation performance of engineered strain was similar with the parental strain. • No residual heterologous genes were left in the genome after genetic manipulation. • An efficient CRISPR vector was constructed and applied for DUR3 over-expression. • Multi-modification of urea cycle had synergistic effect on reducing EC level. • Fermentation performance of engineered strain was similar with the parental strain. • No residual heterologous genes were left in the genome after genetic manipulation.

A special levan-type exopolysaccharide (EPS) from Bacillus amyloliquefaciens JN4 with antiadhesive activity against enterotoxigenic Escherichia coli (ETEC) was purified and identified. Chemical analysis indicated that EPS-JN4 with a low molecular weight of 8 kDa is composed of fructose and glucose with a molar ratio of 46.1:1. Structural analysis clarified that EPS-JN4 contains a main chain of β-(2,6)-linked Fruf residues and intensive branches of a single 2-linked Fruf at every six residues. Furthermore, the superior antiadhesive activity of EPS-JN4 against ETEC showed its potential usage as an antiadhesive agent for diarrhea prevention. EPS-JN4 is a specific type of levan family, for its small molecular size and intensive branches. The results expand the knowledge on structural types of levan and illustrate its potential as an antiadhesive agent for diarrhea prevention, which will be conducive to elucidate the relation between structure and function.

To investigate the effect of the raw material composition on the nano-adhesive characteristics of styrene-butadiene-styrene (SBS) copolymer-modified bitumen, force-distance curves were obtained to examine the nano-adhesive forces of SBS-modified bitumen samples prepared using different virgin bitumen types, SBS modifiers, an extraction oil, and a stabilizer using atomic force microscopy (AFM). The influence of the composition of the raw materials, such as the virgin bitumen, SBS modifier, extracting oil, and stabilizing agent contents, on the cohesive characteristics were discussed for SBS-modified bitumen. The results show that force-distance curves obtained using AFM can be used to gain insight into nano-adhesive forces of SBS-modified bitumen samples. The force-spectrum technique using AFM can be used to obtain the nano-adhesive forces of the SBS-modified bitumen samples. Neat bitumen has good compatibility with a SBS modifier, which is suitable for forming SBS-modified bitumen with an increased nano-adhesive force. The nano-adhesive force of the branched-shaped SBS-modified bitumen was larger than that of linear-shaped SBS-modified bitumen. The nano-adhesive force of SBS-modified bitumen increased as the SBS modifier and stabilizer contents increased. The nano-adhesive force of the SBS-modified bitumen decreased when the extraction oil content increased.

Boron carbide (B4C) is an important type of neutron radiation shielding material with relatively high efficiency due to the high content of 10B element. Incorporation of B4C particles into polymer to prepare high-performance neutron radiation shielding material has become more and more important for the safe operation of nuclear power in the defense industry and nuclear power plant. The polyimide/B4C composite films with different micro-sized B4C contents were successfully prepared by in-situ polymerization. Silane coupling agent KH550 was employed to functionalize B4C particles to improve the dispersion of B4C particles in the polyimide matrix with strengthened interfacial interaction. As shown that the micro-sized B4C functional particles can be well dispersed in the BPDA/ODA polyimide matrix. With the B4C content increase, thermal stability of the polyimide/B4C composite films can be significantly improved, even mechanical properties partly declined. Meanwhile, the polyimide/B4C composite films exhibit good thermal neutron radiation shielding properties. The neutron permeability I/I0 changes exponentially with the change of B4C content. When the B4C content is increased to 30 wt%, the polyimide/B4C composite films show optimum properties combination with thermal decomposition temperature (Td10) of 622 °C, neutron permeability (I/I0) of 0.24 (800 μm in thickness), and tensile strength of 406 MPa. The composite thus shows great potential for use in applications which require materials with high thermal stability and neutron radiation shielding ability, such as fusion reactor system and nuclear waste disposal.

To optimize the expression of type A ferulic acid esterase (FaeA) from Aspergillus niger in Pichia pastoris X-33 using codon optimization. Recombinant FaeA was purified from the fermentation broth, with the maximum specific activity of 48.4 ± 0.1 U mg−1. Adding it during mashing process for beer brewing raised the filtration rate by 14.5% while the turbidity and viscosity declined by 22 and 6.9%, respectively. Addition of FaeA increased the concentrations of free ferulic acid (FA) and arabinoxylan (AX) in the wort, while the polymeric arabinoxylans content declined significantly. Recombinant FaeA was capable to prevent the oxidative gelation of PAX formation by breaking the cross-linking of FA among AX chains and improve the filtration performance of wort.

It is a challenge to simultaneously treat the combined pollutants of chromium(VI) (Cr(VI)) and organics (such as phenol) in wastewater. Here, a stable and efficient redox system based on FeS2 sulfidated zero valent iron (FeS2/Fe0) and persulfate (PS) was developed to synchronously remove Cr(VI) and phenol. 100% of phenol (10 mg/L) was oxidized in 10 min and Cr(VI) (20 mg/L) was completely reduced to Cr(III) in 90 min in the FeS2/Fe0+PS system with a pH range of 3.0–9.0, respectively. phenol was selectively oxidized without re-oxidizing Cr(III) in such system. The surface-bound Fe2+ was the major reactive species to synchronously reduce Cr(VI) and oxidize phenol. The mechanisms were elucidated that the phenol degradation was accelerated by the generated Cr(III) complexing with its products, and that SO42−, whose production speed was accelerated by the PS activation to oxidize phenol and FeS2, was conductive to corrode Fe0 to regenerate the surface-bound Fe2+ for reducing Cr(VI) and oxidizing phenol. It is potential to develop a high-performance and large-scaled FeS2/Fe0-based redox platform to remediate the complex pollution of Cr(VI) and organics.

Single-drug therapy for cancer is greatly hampered by its poor water-solubility, difficulties in controlling and predicting the drug release that limited to the clinical application. In order to overcome these limitations, a novel self-assembled nanoparticle platform based on pectin-eight-arm-polyethylene glycol (8arm-PEG-COOH)-dihydroartemisinin (DHA) conjugate was first presented. Pet-8arm-PEG10K-DHA conjugate was synthesized by introducing hydrophobic drugs DHA to hydrophilic polymer Then, another anticancer drug hydroxycamptothecin (HCPT) was encapsulated into the self-assembled nanoparticles (PPDH NPs). The obtained nanoparticles possessed appropriate size (~ 84 nm), drug-loaded efficiency (~ 9.13 wt% DHA), encapsulation efficiency (~ 12.03 wt% HCPT), good stability and pH-dependent. The time-dependent cytotoxic of the PPDH NPs was only 4% 4T1 cell survived after 72 h. PPDH nanoparticle exhibited a higher cytotoxicity, longer blood retention time of free drug (8.0-fold DHA, 7.4-fold HCPT) and more ef...

Copper (Cu) wire is a good alternative to expensive gold (Au) wire for wire bonding interconnects in many semiconductor and microelectronic applications. However, Cu wire does pose some challenges, like it is harder than Au wire and it easily oxidize in air especially with moisture. Cu oxide layer is not a passivation layer and it will continue to grow. The Cu oxide will hinder the adhesion between wire and pad and lead, causing non-stick-on-pad (NSOP) and non-stick-on-lead (NSOL). Therefore, the shelf life and floor life of Cu wire is much shorter than that of Au wire, and special package and storage techniques are needed for Cu wire. Normally, Cu wire floor life is about 7 days, which means the wire can last for 7 days in clean room after opening the vacuum package.In this work, a batch of Cu wires were found to be severely oxidized in a production clean room, where they were open and hung on the wire bonder after 2-3 days. Surface analysis was conducted on the problematic wire. Time-of-Flight Secondary Ion Mass Spectrometry (TOF-SIMS) and X-ray Fluorescence Spectrometer (XPS) are employed to identify the corrosion products on the Cu wire. The results show that the corrosion products are CuCl and CuO. It is suspected that the chloride (Cl) may come from the Cl-contained floor detergent. Simulation test was conducted to verify the contamination source in the production clean room, and the simulation results match well with the actual results. It is suggested that the assembly houses should use Cl-free detergent in the production room to prevent potential Cl contamination.

During the mashing process for brewing beer, incomplete degradation of arabinoxylan in barley malt may cause an intense filterability problem. The present study cloned a putative arabinofuranosidase (AnAbf), one of the debranching enzymes, from Aspergillus niger, to explore its application for improving filterability. Recombinant AnAbf (rAnAbf) showed activity towards both synthetic and natural substrates, such as 4-nitrophenyl α- l -arabinofuranoside (pNPαAraf) and malt water extractable arabinoxylan (WEAX), which was maximized at a temperature of 50 °C and pH of 5.5. Metal ions did not increase the activity of rAnAbf, indicating a difference in its C-terminal domain from that of type II GH43 family members. rAnAbf also exhibited a synergistic effect with β-xylanase against WEAX. The filtration rate of the wort increased by 12.8% after supplementing with rAnAbf during the initial stage of mashing. A slight decrease in viscosity and an unexpected increase in turbidity were observed.

This study developed a multiple-parameter equilibration-based kilning technology optimization method with a Box–Behnken factorial design and response surface methodology, assessing 10 kinds of indexes from multiple perspectives, including malt stale flavour, malty aroma and sensory evaluation, simultaneously. The results indicated that lipoxygenase (LOX) activity, nonenal potential and sensory score had a tendency to decline, while 4-hydroxy-2,5-dimethyl-3 (2H)-furanone, thiobarbituric acid (TBZ) and stale aldehydes increased with the rise in kilning temperature, the extension of kilning time and withering time. The corresponding second-order mathematical models were established for predicting each parameter. Among them, p-values of a model equation of LOX activity, nonenal potential, 4-hydroxy-2,5-dimethyl-3(2H)-furanone, TBZ, methional and furfural were all 0.9, which indicated that these equations had higher significance and that data in excess of 90% could be explained. Subsequently, the numerical optimization of kilning technology was carried out for balancing these positive or negative parameters and the optimum kilning temperature, kilning time and withering time were found to be 86.35 °C, 3.19 h and 14.00 h, respectively. Compared with the values of the original response, the values of the 10 parameters were optimized from 2.2 to 65.2%. This method offers an ability to monitor malt characteristics to obtain higher quality malt. Further, the method will help maltsters and brewers to comprehensively understand malt with different cultivar genetics and growing environments. Copyright © 2016 The Institute of Brewing & Distilling

Ethyl carbamate is a potential carcinogenic compound derived from the spontaneous reaction of ethanol with urea and citrulline in Chinese rice wine. The strain Lactobacillus brevis 2-34 isolated from Chinese rice wine fermentation liquor showed high citrulline re-uptake capacity in both single and co-culture systems. The present study therefore supplemented this strain with starter inoculations in Chinese rice wine fermentation, with the aim to decrease citrulline and subsequent ethyl carbamate content. The final Chinese rice wine liquor contained less citrulline and ethyl carbamate, as well as several harmful higher alcohols, and more esters which contributed to flavors. Gene sequencing showed the presence of the dcuC and transporter genes, for which the encoded proteins may be responsible for citrulline transportation. This study showed a possible way to control citrulline and ethyl carbamate in Chinese rice wine and also showed some aspects of the citrulline transport mechanism.

Aluminum (Al) has been used as an interconnection material for the last 40 years. As the ultra-largescale integrated devices become more and more smaller, there are demands for the semiconductor gate performance to be improved through the use of a higher drive current and a lower junction capacitance. One attempt is to replace the conventional Al interconnection with copper (Cu), as Cu has lower electrical resistivity and enhanced electromigration resistance. Thermosonic wire bonding has been extensively developed and applied in bonding technique. It uses both heat and ultrasonic energy to obtain a solid-state diffusion between the bonded ball and pad. For the traditional Al bond pad, it naturally forms a passivation layer, alumina (Al 2 O 3 ), on the surface. The Al 2 O 3 prevents the continual oxidation of Al pad, and this brittle Al 2 O 3 layer is broken by the ultrasonic energy during the thermosonic bonding. However, for the Cu pad, it is well known that it readily oxidizes at air atmosphere, especially with moisture, as Cu oxide is not a passivation layer and it will continually grow, which block the subsequent solid diffusion during wire bond process. Therefore, it is necessary to study the behavior of Cu pad IMC. In this paper, gold (Au) wire was thermosonic bonded to Cu pad. The IMC (intermetallic compound) coverage was characterized. HTS (high temperature storage) study was conducted and a comprehensive study on the interfacial behavior of thermally aged Au-Cu was conducted using transmission electron microscopy. It was found that Au-Cu IMC grew slower than that of Au-Al and Cu-Al, and the thickness of Au-Cu is 100-250nm after HTS 150°C, 1000 hours.

A core-shell Cu-benzene-1,3,5-tricarboxylic acid (Cu-BTC)@TiO2 was successfully synthesized for photocatalysis-assisted adsorptive desulfurization to improve adsorptive desulfurization (ADS) performance. Under ultraviolet (UV) light irradiation, the TiO2 shell on the surface of Cu-BTC achieved photocatalytic oxidation of thiophenic S-compounds, and the Cu-BTC core adsorbed the oxidation products (sulfoxides and sulfones). The photocatalyst and adsorbent were combined using a distinct core-shell structure. The morphology and structure of the fabricated Cu-BTC@TiO2 microspheres were verified by scanning electron microscopy, high-resolution transmission electron microscopy, energy-dispersive x-ray spectroscopy, X-ray powder diffraction, nitrogen adsorption-desorption and X-ray photoelectron spectroscopy analyses. A potential formation mechanism of Cu-BTC@TiO2 is proposed based on complementary experiments. The sulfur removal efficiency of the microspheres was evaluated by selective adsorption of benzothiophene (BT) and dibenzothiophene (DBT) from a model fuel with a sulfur concentration of 1000 ppmw. Within a reaction time of 20 min, the BT and DBT conversion reached 86% and 95%, respectively, and achieved ADS capacities of 63.76 and 59.39 mg/g, respectively. The BT conversion and DBT conversion obtained using Cu-BTC@TiO2 was 6.5 and 4.6 times higher, respectively, than that obtained using Cu-BTC. A desulfurization mechanism was proposed, the interaction between thiophenic sulfur compounds and Cu-BTC@TiO2 microspheres was discussed, and the kinetic behavior was analyzed.

Most of the fermented alcoholic beverages, particularly Chinese rice wine, contain the potentially human carcinogenic compound ethyl carbamate (EC). As a major EC precursor in Chinese rice wine, urea in fermentations can be transported into the yeast cell by urea permease and finally metabolized by urea carboxylase and allophanate hydrolase in vivo. To eliminate EC in Chinese rice wines, the present study constructed high urea uptake yeast strains N1-D, N2-D and N-D, by introducing a strong promoter (PGK1p) into the urea permease gene (DUR3) of the industrial Chinese rice wine yeast N85, and by the restoration of the URA3 gene at the same time. With these self-cloned, high urea uptake strains, the urea and EC in the terminal Chinese rice wine samples were reduced to different extents. With two copies of overexpressed DUR3, the N-D strain could reduce the urea and the EC by 53.4 and 26.1%, respectively. No difference in fermentation characteristics was found between the engineered strains and the parental industrial yeast strain N85. These results could help to optimize the genetic manipulation strategy for EC elimination in Chinese rice wine production. Copyright © 2015 The Institute of Brewing & Distilling

Premature yeast flocculation (PYF) is a universal phenomenon and has caused serious problems in the brewing industry. For brewing quality control, it is of great value to investigate the PYF factors that induce this destructive phenomenon. In the present study, two barley malts (PYF+ and PYF−), made from the same barley cultivar by one maltster in China, were selected for PYF factor investigations. The results showed that considerably higher amounts of the bound ferulic acid (FA), rather than arabinoxylan (AX), existed in the PYF+ wort compared with the PYF− wort. To better understand the role of these polysaccharides in PYF+ and PYF− wort, they were fractional precipitated with graded ethanol concentrations. The AX and FA contents in each fraction, as well as the molecular weight profiles and monosaccharide composition, were determined. Furthermore, the PYF−inducing activities of each fraction were measured using a small-scale fermentation. It was found that the 40% ethanol-precipitated fraction of both the PYF+ and PYF− wort, and the 60% fraction from the PYF+ wort, could induce the severe PYF phenomenon when added to the PYF− wort. These fractions were proposed to contain PYF factors of suitable molecular weight and a sufficient amount of the polysaccharides. In addition, it was found that the bound FA in arabinoxylan behaved as an important PYF factor in barley malt. The results of this work may contribute to the further study of the PYF mechanism. Copyright © 2015 The Institute of Brewing & Distilling

The application of non-toxic carriers to increase drug loading, multi-drug delivery, and extremely small size of nano-drugs to construct a tremendous transmission system is the goal for all researchers to be pursued. The proposal of natural pectin nano-platform for delivery of multiple drugs is critical for biomedical research, especially a particle size of below 100nm with high yield. Here we design a new core-shell structure pectin-eight-arm polyethylene glycol-ursolic acid/hydrooxycampothecin nanoparticle (Pec-8PUH NPs) through a special self-assembly method for stabilizing and dispersing particles, improving water-solubility, and achieving drug controlled release. The obtained Pec-8PUH NPs possessed appropriate size (~91nm), drug-loaded efficiency and encapsulation efficiency through the regulation of eight-arm polyethylene glycol. In addition, Pec-8PUH NPs could enhance cell cytotoxicity, shorten blood retention time (7.3-fold UA, 7.2-fold HCPT) and more effective cellular uptake than free drugs, which exhibited an obvious synergistic effect of UA and HCPT by the co-delivery. 4T1 tumor-bearing mice also showed a higher survival rate than free UA and free HCPT. The result further shows that this novel drug delivery system has a promising potential for anti-cancer combination therapy.

TEMJEDX analysis techniques are widely used in failure analysis. Based on TEM results, one can know the structures of the sample e.g. in anomalous or crystalline, as well as the thickness of the thin film layer. Typically, TEM/EDX results can only provide the elemental information of the sample. In this paper, we discussed a standardless EDX analysis method to identify the chemical state composition for an unknown sample. Generally, it is to use the atomic percentage Wia' (excluding Pt from the sample preparation), which can be easily achieved by a certain data processing, to identify the chemical state composition. For example, in this paper, we studied the layers composition on Cu substrate, which was consisting of CuO and CuiO.

The effects of different dissolved oxygen concentrations (DOC) on the browning degree, amino acids, total phenols, reducing sugars, polyphenoloxidase (PPO), peroxidase (POD), phenylalanine ammonia-lyase (PAL) of pear wine, and the relationship between various quality indicators and browning degree were investigated. Dynamic model fitting analysis of the changes of physiochemical indicators of pear wine in the storage process were performed. The importance of the physiochemical indicators effect on the browning of pear wine during the storage process was analyzed by OPLS (orthogonal partial least squares discriminant analysis), and the effect of dissolved oxygen on the browning of pear wine was systematically revealed. The results showed that dissolved oxygen, total phenols and amino acids had the greatest influence on the browning degree of pear wine. It provided a theoretical basis for revealing the browning mechanism and inhibiting the browning of pear wine.

The malting process is the controlled germination, followed by drying, of the barley grain. For brewing beer, the malting process is modified according to the features of the barley variety being malted. In China, there are two schedules routinely used for malting the widely grown Dan'er cultivar, processes I and II. The quality of malt produced with process II is considered to be superior to that from process I for Dan'er by maltsters and brewers. In the present study, comparative proteomic analysis was performed between Dan'er malts produced by malting processes I and II. The data showed that enzymes and proteins responsible for cell wall polysaccharide degradation and starch and protein hydrolysis were more abundant in malt produced by process II, leading to improved quality, especially for the commercially important filterability, saccharification time, and diastatic power (DP) quality traits. In addition, to verify the proteomic results, the activities of several key enzymes (α-amylase, β-amylase, and limit dextrinase) were compared between the two malts. This enabled the influence of malting process on malt quality to be determined and suggested malting process schedule changes to optimize the malting process for the Dan'er cultivar, especially for improving filterability, which is often deemed as suboptimal by maltsters and brewers.

Saccharomyces cerevisiae metabolizes arginine to ornithine and urea during wine fermentations. In the fermentation of Chinese rice wine, yeast strains of S. cerevisiae do not fully metabolize urea, which will be secreted into the spirits and spontaneously reacts with ethanol to form ethyl carbamate, a potential carcinogenic agent for humans. To block the pathway of urea production, we genetically engineered two haploid strains to reduce the arginase (encoded by CAR1) activity, which were isolated from a diploid industrial Chinese rice wine strain. Finally the engineered haploids with opposite mating type were mated back to diploid strains, obtaining a heterozygous deletion strain (CAR1/car1) and a homozygous defect strain (car1/car1). These strains were compared to the parental industrial yeast strain in Chinese rice wine fermentations and spirit production. The strain with the homozygous CAR1 deletion showed significant reductions of urea and EC in the final spirits in comparison to the parental strain, with the concentration reductions by 86.9% and 50.5% respectively. In addition, EC accumulation was in a much lower tempo during rice wine storage. Moreover, the growth behavior and fermentation characteristics of the engineered diploid strain were similar to the parental strain.

Ethyl carbamate is a well-known carcinogen and widely occurs in Chinese rice wine. To provide more clues to minimise ethyl carbamate accumulation, the levels of possible precursors of ethyl carbamate in Chinese rice wine were investigated by HPLC. Studies of the possible precursors of ethyl carbamate in Chinese raw rice wine with various additives and treatments indicated that significant amounts of urea can account for ethyl carbamate formation. It was also recognised that citrulline is another important precursor that significantly affects ethyl carbamate production during the boiling procedure used in the Chinese rice wine manufacturing process. Besides urea and citrulline, arginine was also found to be an indirect ethyl carbamate precursor due to its ability to form urea and citrulline by microorganism metabolism.

Three-dimensional (3D) flower-like Co–Al layered double hydroxide (Co–Al-LDH) architectures composed of atomically thin nanosheets were successfully synthesized via a hydrothermal method in a mixed solvent of water and butyl alcohol. Owing to the unique hierarchical structure and modification by butyl alcohol, the electrochemical stability and the charge/mass transport of the Co–Al-LDHs was improved. When used in supercapacitors, the obtained Co–Al-LDHs deliver a high specific capacitance of 838 F g−1 at a current density of 1 A g−1 and excellent rate performance (753 F g−1 at 30 A g−1 and 677 F g−1 at 100 A g−1), as well as excellent cycling stability with 95% retention of the initial capacitance even after 20,000 cycles at a current density of 5 A g−1. This work provides a promising alternative strategy to enhance the electrochemical properties of supercapacitors. Electronic supplementary material The online version of this article (doi:10.1007/s40820-016-0121-5) contains supplementary material, which is available to authorized users.

Sus scrofa lysozyme (SSL), an important component of the pig immune system, is a potential candidate to replace antibiotics in feed. However, there is little antimicrobial activity of natural SSL against gram-negative bacteria, which limits its application. In this study, a unique peptide (A-W-V-A-W-K) with antimicrobial activity against gram-negative bacteria was discovered and purified from trypsin hydrolysate of natural SSL. This unique peptide was fused to natural SSL and the recombinant fused SSL exhibited improved activity against gram-negative bacteria. The N-terminal fusion likely increased the membrane penetrability and induced programmed bacterial cell death. The recombinant fused SSL also showed higher activity against some gram-positive bacteria with O-acetylation. By N-terminal fusion of the sextuple peptide, the anti-microbial activity, either to gram-positive or negative bacteria, of the recombinant SSL was higher than the fusion of only one copy of the peptide. This study provides a general, feasible, and highly useful strategy to enhance the antimicrobial activity of lysozyme.

Urea and ethanol are the main precursors of ethyl carbamate (EC) in Chinese rice wine. During fermentation, urea is generated from arginine by arginase in Saccharomyces cerevisiae, and subsequently cleaved by urea amidolyase or directly transported out of the cell into the fermentation liquor, where it reacts with ethanol to form EC. To reduce the amount of EC in Chinese rice wine, we metabolically engineered two yeast strains, N85(DUR1,2) and N85(DUR1,2)-c, from the wild-type Chinese rice wine yeast strain N85. Both new strains were capable of constitutively expressing DUR1,2 (encodes urea amidolyase) and thus enhancing urea degradation. The use of N85(DUR1,2) and N85(DUR1,2)-c reduced the concentration of EC in Chinese rice wine fermented on a small-scale by 49.1% and 55.3%, respectively, relative to fermentation with the parental strain. All of the engineered strains showed good genetic stability and minimized the production of urea during fermentation, with no exogenous genes introduced during genetic manipulation, and were therefore suitable for commercialization to increase the safety of Chinese rice wine.

As a major component of non-starch polysaccharide in barley, arabinoxylan (AX) plays an important role in quality traits of malt and the final beer product. The Chinese barley malt has encountered filterability problems for a long time. The main reason caused by barley cultivar has been accepted in the malting and brewing industries. In our previous proteomic study, the peroxidase (POD) BP1 was found to be in quite high abundant in the filterability defect Chinese barley malt. Therefore, the present study tried to verify its negative effect on filterability, by surveying its activity in different malt samples and detecting effects of POD on AX gelation and filterability. The results showed that the activity of POD, as well as the content of AX bounded ferulic acid, were both negatively correlated with filterability, while the feruloyl esterase activity was positively correlated with it. In addition, AX gelation catalyzed by POD caused worse filterability, and the natural inhibitor of POD, vitamin C, could blocked the cross linking catalyzed by POD and thus improve the filterability. These results all suggested the great negative effect of POD on malt filterability.

A series of novel 1-substituted-2-aminobenzimidazole derivatives were synthesized. The structures of the synthesized compounds were confirmed by 1 H-NMR spectra and by elemental analysis. Acute toxicities of these compounds were detected on mice via toxicity (logLD 50 ). QSAR analysis of these chemicals was studied on the relationship between acute toxicity and the octanol/water partition coefficient (Log P ). The products were identified by the results of elemental analysis and 1 H-NMR spectra. The toxicity (logLD 50 ) of 2-aminobenzimidazole 1-substituents were correlated well with the partition coefficient Log P , r = 0.9243. The bioactivity (toxicity) of 2-aminobenzimidazoles can be predicted by the molecular structural parameter such as Log P .

Dan'er is a widely grown malt barley cultivar in China, but its filterability defects have severely impeded its application in beer brewing. Previous investigations have suggested that we should identify the malt filterability correlated proteins, one of which was postulated to be arabinoxylan arabinofuranohydrolase I (AXAH-I). To verify this hypothesis, we purified AXAH-I from Dan'er malt, characterised its enzyme performance, and investigated its influence on filterability by adding different amounts of purified enzyme to the mash. With 6 mU g(-1) malt AXAH-I supplemented, the wort separation rate increased by 31.8%, viscosity decreased by 3.6%, and the endosperm reserve contents declined concomitantly. Unexpectedly, the wort turbidity increased with increasing AXAH-I. We also tried to optimise the use of currently available commercial enzyme products for filterability improvement in beer brewing, by supplementing them with purified AXAH-I and β-amylase. AXAH-I could be a functional component for novel commercial enzyme products in the beer industry.