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AbstractWith the industrialization and development of modern science, the application of enzymes as green and environmentally friendly biocatalysts in industry has been increased widely. Among them, lipase (EC. 3.1.1.3) is a very prominent biocatalyst, which has the ability to catalyze the hydrolysis and synthesis of ester compounds. Many lipases have been isolated from various sources, such as animals, plants and microorganisms, among which microbial lipase is the enzyme with the most diverse enzymatic properties and great industrial application potential. It therefore has promising applications in many industries, such as food and beverages, waste treatment, biofuels, leather, textiles, detergent formulations, ester synthesis, pharmaceuticals and medicine. Although many microbial lipases have been isolated and characterized, only some of them have been commercially exploited. In order to cope with the growing industrial demands and overcome these shortcomings to replace traditional chemical catalysts, the preparation of new lipases with thermal/acid-base stability, regioselectivity, organic solvent tolerance, high activity and yield, and reusability through excavation and modification has become a hot research topic. [ABSTRACT FROM AUTHOR]

This study aimed to investigate the effect of mutating the consensus pentapeptide on the enzymatic properties and structural characteristics of Bacillus licheniformis lipase. Site-directed mutagenesis was used to construct mutants and then expressed in Escherichia coli BL21. After purification and enzyme activity analysis, only A75C and A75G retained activity. Compared to the wild-type lipase and A75G, the A75C showed higher thermostability at 40°C and better alkali resistance in pH 9.0–10.0 after incubation for 1 h. The kinetic parameters, structural characteristics and surface hydrophobicity of the lipases were determined. The results indicated that the secondary structure was hardly changed, while mutants exhibited higher activity, thermostability and hydrophobicity. Finally, the reasons for the increased enzyme activity were conducted through molecular dynamics simulation. The strategy of mutating the first residue of the lipase consensus pentapeptide may provide new insights into the enzyme engineering for industrial applications. [ABSTRACT FROM AUTHOR]

A novel lipase, SCNL, was isolated from Staphylococcus caprae NCU S6 strain in the study. The lipase was purified to homogeneity with a yield of 6.13% and specific activity of 502.76 U/mg, and its molecular weight was determined to be approximately 87 kDa. SCNL maintained above 80% of its initial activity at a wide range of temperatures (20–50 °C) and pH values (6–11), with an optimal temperature at 40 °C and optimal pH at 9.0 with p-nitrophenyl palmitate as a substrate. SCNL exhibited a higher residual activity than the other staphylococcal lipases in the presence of common enzyme inhibitors and commercial detergents. The lipase activity was enhanced by organic solvents (isooctane, glycerol, DMSO and methanol) and metal ions (Na+, Ba2+, Ca2+, and Mn2+). The Km and Vmax values of SCNL were 0.695 mM and 262.66 s−1 mM−1, respectively. The enzyme showed a preference for p-NP stearate, tributyrin and canola oil. These biochemical features of SCNL suggested that it may be an excellent novel lipase candidate for industrial and biotechnological applications. [ABSTRACT FROM AUTHOR]

• A novel structural lipid was produced from CCSKO, PBST and PSO. • EIE had significantly lower SMP and SFC values than NIE. • The crystal forms of lipids were changed after enzymatic interesterification. • EIE showed improved rheological behavior than NIE. The study aimed to investigate the effect of enzymatic interesterification on the lipid composition, physicochemical properties and rheological behavior of Cinnamomum camphora seed kernel oil (CCSKO), Pangasius bocourti stearin (PBST) and perilla seed oil (PSO) blends. The results showed that the interesterification process significantly changed the TAG profile of the blends. Lipid products from the enzymatic interesterification (EIE) had significantly lower slide melting point and solid fat content than the non-interesterification (NIE) lipid products. Interesterification process changed the crystal polymorphic forms from β > β′ of NIE to β < β′ of EIE. The crystal morphology of EIE was smaller and more diffuse compared to the NIE. Moreover, EIE showed improved rheological behavior, which was more suitable for food margarine preparation. The findings have provided a theoretical basis for the potential application of Lipozyme TL IM modified lipid products in the food industry. [ABSTRACT FROM AUTHOR]

The study aimed to investigate the effects of processing methods on oil yield, chemical composition, physicochemical properties, antioxidant activity and volatile compounds of Cinnamomum camphora seed kernel oil (CCSKO). The processing methods used were hot pressing (HP), cold pressing (CP), solvent extraction (SE), aqueous extraction (AE), sub-critical fluid extraction (SCFE) and supercritical fluid extraction (SFE). The results showed that the extraction efficiencies from different processing methods ranged from 44.48% to 97.93%, with the highest efficiency from SCFE. All CCSKO samples were found to be rich in medium-chain saturated fatty acids (> 96%), and capric acid-capric acid-lauric acid accounting for the largest proportion of triacylglycerols (77.54%−78.74%). However, the total polyphenol content, δ-tocopherol content and antioxidant activity of AE, α-tocopherol and γ-tocopherol content of CP, and squalene content of SCFE were all significantly higher than those of the other samples. Additionally, the thermal behaviors and spectral profiles of all samples were similar. Furthermore, there were significant differences in the volatile compounds of CCSKO with different processing methods (p < 0.05). Linalool, 2-nonanol, and ethyl caprate were determined to be the key aroma compounds of CCSKO. Overall, the results provide a theoretical reference for further processing of CCSKO. • Six processing methods for Cinnamomum camphora seed kernel oil (CCSKO) were explored. • CCSKO obtained by aqueous extraction showed the highest antioxidant activity. • Processing methods had a significant effect on the volatile compounds of CCSKO. • Linalool, 2-nonanol and ethyl caprate were the key odor contributors of CCSKO. [ABSTRACT FROM AUTHOR]

Aflatoxin B 1 (AFB 1) contamination in peanut oil is a serious food safety concern. Classical edible oil refining process is an effective approach to remove AFB 1. However, the transformation pathway, structure, and distribution of the transformation product of AFB 1 in edible oil refining have not yet been reported in detail. In this work, we demonstrated that the degumming and deacidification were the critical phases for AFB 1 removal from crude oil, in which 4.77% and 7.32% of AFB 1 were transferred into the colloidal impurities and soap stock, and 87.91% of AFB 1 was transformed to other compound. UPLC-Q-TOF MS and NMR analysis revealed that the AFB 1 transformation product in peanut oil refining resulted from the hydrolysis of the lactone ring of AFB 1. The lactone ring opened AFB 1 (named OP-AFB 1) in the soap stock can be converted into the original AFB 1 under acidic conditions. Thus, the OP-AFB 1 in soap stock was further detoxified via the Fenton treatment. [Display omitted] • The transformation pathway, structure, and distribution of the AFB 1 transformation product during peanut oil refining were described. • The Fenton reaction was used to further detoxify AFB 1 transformation product. • The AFB 1 elimination in edible oil refining provides a powerful theoretical basis for the safety of refined edible oil. [ABSTRACT FROM AUTHOR]

Nitrogen and oxygen codoped carbon nanosheets derived from pre-functionalized polymer were prepared using a facile direct pyrolysis method. The carbon microstructures are tunable with micro- and mesopore size distribution and a large specific surface area (1628.9–2146.1 m 2  g −1 ). Furthermore, a significant morphology change, from carbon granules to carbon nanosheets, occurred at an annealing temperature of 1273 K. The unique carbon sheet morphology guaranteed a good specific capacitance of 246.4 F g −1 at 0.5 A g −1 in 1 M H 2 SO 4 aqueous solution and an excellent rate capability with a retention of 87.9% at 5 A g −1 as coin cell. The outstanding capacitance attributes to the combination of pseudocapacitance due to the N,O dual-doping and unique nanosheet morphology. Moreover, its outstanding cycling performance with 95% retention over 10,000 cycles at 10 A g −1 and an acceptable energy density of 8.6 Wh kg −1 at 0.2 A g −1 make the N,O-codoped carbon nanosheet potent and promising electrode material for high performance supercapacitors. [ABSTRACT FROM AUTHOR]

Methicillin-resistant Staphylococcus aureus (MRSA) is a drug-resistant pathogen generally derived from pork and other animal foods. This study investigated the antibacterial mechanism of monocaprin against MRSA and its preservation effect on pork. The results showed that monocaprin had a strong anti-MRSA activity with visible cell surface damage and a minimum inhibitory concentration of 0.16 mg/mL. The transcriptomic and metabolomic analyses showed that 255 genes, 45 metabolites in positive ion mode, and 50 in negative ion mode were significantly changed after monocaprin treatment (0.08 mg/mL). The integrative analysis of omics suggested that monocaprin led to osmotic imbalance, amino acid metabolism inhibition, energy metabolism disorder and aerobic respiration obstruction of MRSA. Sublethally damaged MRSA required increased specific protein synthesis and pyrimidine metabolism, enhanced glycolysis, activation of anaerobic respiration, and promotion of biofilm formation for survival under monocaprin stress. Moreover, monocaprin obviously restrained the growth of MRSA in pork, delayed the spoilage of pork during storage at 4 °C for 8 days, and had no adverse effects on its sensory properties. Overall, these results revealed the anti-MRSA mechanism of monocaprin and suggested that monocaprin can be used to control MRSA in pork. • Monocaprin exhibited a strong antibacterial activity against MRSA. • Monocaprin induced changes in transcriptional and metabolic levels of MRSA. • Monocaprin led to osmotic imbalance and nutrients metabolism disorder. • Injured cells required increased protein synthesis and pyrimidine metabolism for survival. • Monocaprin effectively inhibited MRSA in pork during storage at 4 °C for 8 days. [ABSTRACT FROM AUTHOR]

Currently, less favorable C=O hydrogenation and weak concerted acid catalysis cause unsatisfactory catalytic performance in the upgrading of biomass‐derived furfurals (i.e., furfural, 5‐methyl furfural, and 5‐hydroxymethyl furfural) to ketones (i.e., cyclopentanone, 2,5‐hexanedione, and 1‐hydroxyl‐2,5‐hexanedione). A series of partially oxidized MAX phase (i.e., Ti3AlC2, Ti2AlC, Ti3SiC2) supporting Pd catalysts were fabricated, which showed high catalytic activity; Pd/Ti3AlC2 in particular displayed high performance for conversion of furfurals into targeted ketones. Detailed studies of the catalytic mechanism confirm that in situ hydrogen spillover generates Frustrated Lewis H+−H− pairs, which not only act as the hydrogenation sites for selective C=O hydrogenation but also provide acid sites for ring opening. The close intimate hydrogenation and acid sites promote bifunctional catalytic reactions, substantially reducing the reported minimum reaction temperature of various furfurals by at least 30–60 °C. [ABSTRACT FROM AUTHOR]

Currently, less favorable C=O hydrogenation and weak concerted acid catalysis cause unsatisfactory catalytic performance in the upgrading of biomass‐derived furfurals (i.e., furfural, 5‐methyl furfural, and 5‐hydroxymethyl furfural) to ketones (i.e., cyclopentanone, 2,5‐hexanedione, and 1‐hydroxyl‐2,5‐hexanedione). A series of partially oxidized MAX phase (i.e., Ti3AlC2, Ti2AlC, Ti3SiC2) supporting Pd catalysts were fabricated, which showed high catalytic activity; Pd/Ti3AlC2 in particular displayed high performance for conversion of furfurals into targeted ketones. Detailed studies of the catalytic mechanism confirm that in situ hydrogen spillover generates Frustrated Lewis H+−H− pairs, which not only act as the hydrogenation sites for selective C=O hydrogenation but also provide acid sites for ring opening. The close intimate hydrogenation and acid sites promote bifunctional catalytic reactions, substantially reducing the reported minimum reaction temperature of various furfurals by at least 30–60 °C. [ABSTRACT FROM AUTHOR]

Graphene quantum dots (GQDs) are promising for bioimaging applications due to their unique optical properties and good biocompatibility. However, the facile synthesis of GQDs with long-wavelength emission and high quantum yield (QY) under long-wavelength excitation is still a challenge. Herein, dual-emissive GQDs were synthesized via a facile one-pot solvothermal method using 2,7-dihydroxynaphthalene (2,7-DHN) and piperazine anhydrous (PA) as the raw materials. The obtained GQDs exhibited a green-emission band (core state emission) and a red-emission band (surface state emission), which originated from the inner π-conjugated structure and various surface functional groups, respectively. The π-conjugated structure mainly comes from the aromatic rings in 2,7-DHN, and the N–H of PA acts as the main nitrogen source, which is beneficial for the QY. The obtained GQDs showed obvious concentration-dependent optical properties. Importantly, they are able to generate red emission with a high absolute QY of 54.9% in ethanol and 24.9% in water, among the best values of reported GQDs. In addition, the prepared GQDs have good water-solubility, low cytotoxicity, and superior stability against photobleaching. Based on the above advantages, the as-prepared GQDs were successfully applied for labeling HeLa cells in vitro. Therefore, our prepared GQDs demonstrated that they can be an efficient biomarker for fluorescent bioimaging. [ABSTRACT FROM AUTHOR]

Electrochemical reduction of carbon dioxide (CO2) to ethanol is a promising strategy for global warming mitigation and resource utilization. However, due to the intricacy of C─C coupling and multiple proton–electron transfers, CO2‐to‐ethanol conversion remains a great challenge with low activity and selectivity. Herein, it is reported a P‐doped graphene aerogel as a self‐supporting electrocatalyst for CO2 reduction to ethanol. High ethanol Faradaic efficiency (FE) of 48.7% and long stability of 70 h are achieved at −0.8 VRHE. Meanwhile, an outstanding ethanol yield of 14.62 µmol h−1 cm−2 can be obtained, outperforming most reported electrocatalysts. In situ Raman spectra indicate the important role of adsorbed *CO intermediates in CO2‐to‐ethanol conversion. Furthermore, the possible active sites and optimal pathway for ethanol formation are revealed by density functional theory calculations. The graphene zigzag edges with P doping enhance the adsorption of *CO intermediate and increase the coverage of *CO on the catalyst surface, which facilitates the *CO dimerization and boosts the EtOH formation. In addition, the hierarchical pore structure of P‐doped graphene aerogels exposes abundant active sites and facilitates mass/charge transfer. This work provides inventive insight into designing metal‐free catalysts for liquid products from CO2 electroreduction. [ABSTRACT FROM AUTHOR]

One pot synthesis of 2,5‐dimethylfuran (2,5‐DMF) from saccharides under mild conditions is of importance for the production of biofuel and fine chemicals. However, the synthesis requires a multitude of active sites and suffers from slow kinetics due to poor diffusion in most composite catalysts. Herein, a metal‐acid functionalized 2D metal‐organic framework (MOF; Pd/NUS‐SO3H), as an ultrathin nanosheet of 3–4 nm with Lewis acid, Brønsted acid, and metal active sites, was prepared based on the diazo method for acid modification and subsequent metal loading. This new composite catalyst gives substantially higher yields of DMF than all reported catalysts for different saccharides (fructose, glucose, cellobiose, sucrose, and inulins). Characterization suggests that a cascade of reactions including polysaccharide hydrolysis, isomerization, dehydration, and hydrodeoxygenation takes place with rapid molecular interactions. [ABSTRACT FROM AUTHOR]

One pot synthesis of 2,5‐dimethylfuran (2,5‐DMF) from saccharides under mild conditions is of importance for the production of biofuel and fine chemicals. However, the synthesis requires a multitude of active sites and suffers from slow kinetics due to poor diffusion in most composite catalysts. Herein, a metal‐acid functionalized 2D metal‐organic framework (MOF; Pd/NUS‐SO3H), as an ultrathin nanosheet of 3–4 nm with Lewis acid, Brønsted acid, and metal active sites, was prepared based on the diazo method for acid modification and subsequent metal loading. This new composite catalyst gives substantially higher yields of DMF than all reported catalysts for different saccharides (fructose, glucose, cellobiose, sucrose, and inulins). Characterization suggests that a cascade of reactions including polysaccharide hydrolysis, isomerization, dehydration, and hydrodeoxygenation takes place with rapid molecular interactions. [ABSTRACT FROM AUTHOR]

Cinnamomum camphora seed kernel oil (CCSKO) was found to reduce body fat deposition and improve blood lipid in both healthy and obese rats. The study was aimed to investigate the antioxidative stress and anti-inflammatory effects of CCSKO in high-fat-diet-induced obese rats. The obese rats were treated with CCSKO, lard, and soybean oil, respectively, for 12 wk. The level of total antioxidant capacity (T-AOC), activities of superoxide dismutase (SOD), glutathione peroxidase, and catalase, and levels of malondialdehyde (MDA), tumor necrosis factor (TNF)-α, peroxisome proliferator-activated receptor (PPAR)-γ, interleukin (IL)-6, and P65 were compared among CCSKO, lard, and soybean oil groups. Our results showed that the level of T-AOC and activities of SOD and catalase were significantly increased and the level of MDA was significantly decreased in CCSKO group. In addition, CCSKO treatment reduced the activities of serum glutamic oxaloacetic transaminase and glutamate-pyruvate transaminase, and levels of serum TNF-α, IL-6, and P65 through raising the level of PPAR-γ. In conclusion, CCSKO has, for the first time, been found to ameliorate oxidative stress and inflammation in high-fat-diet-induced obese rats. [ABSTRACT FROM AUTHOR]

Developing a one-pot method for tandem hydrogenolysis–hydrogenation of biomass-derived furan-based alcohols to methyltetrahydrofurans is challenging but crucial for synthesizing sustainable biofuels and chemicals. Herein, we report the efficient hydrogenolysis–hydrogenation of furan alcohol to 2-methyltetrahydrofuran using a phosphate-supported synergistic palladium single atom and nanoparticle at an ambient temperature. Comprehensive characterizations and theoretical calculations reveal that in situ H 2 heterolysis at the palladium single atom–AlPO 4 interface generates frustrated Lewis H+–H− pairs, which selectively cleaves the C–OH bond in furan alcohol to form 2-methylfuran, and H atoms on the palladium nanoparticle surface promotes the subsequent C C hydrogenation of 2-methylfuran to 2-methyltetrahydrofuran. Additionally, the catalyst shows generality for various furan and heterocyclic alcohols. Furthermore, the catalyst exhibits excellent activity in the hydrogenation–hydrogenolysis–hydrogenation of furan aldehydes to methyltetrahydrofurans. The results provide a highly efficient reaction for synthesizing methyltetrahydrofurans at ambient temperature, which has excellent potential for industrial applications. [Display omitted] • Phosphate-supported synergistic palladium single atom and nanoparticle was fabricated. • Methyltetrahydrofurans was selectively obtained from tandem hydrogenolysis–hydrogenation of furan alcohols. • In situ H 2 heterolysis-generated H−–Pd–P–O-H+ site over palladium single atom provides the C–OH hydrogenolysis site. • Palladium nanoparticle promotes the subsequent C C hydrogenation. • The catalyst shows generality for various furan and heterocyclic alcohols. [ABSTRACT FROM AUTHOR]

• For the first time, Co-metal was used for synthesis of carbon nanopearl chains. • A brand-new carbon nanostructure composed of nanospheres and nanofibers. • Growth based on liquid carbon droplets and Rayleigh's instability. Carbon nanopearl chains (CNPCs) consisted of carbon nanospheres and carbon nanofibers were prepared by chemical vapor deposition (CVD) method using benzene as the carbon source and Co particles on Si-substrate as the catalyst. The characterized results confirmed that the carbon nanospheres with a diameter between 80 nm and 300 nm have solid structure and wavy graphite layered surface, while the carbon nanofibers (diameter: 16 nm) showed amorphous structure and excellent flexibility. Therefore, these synthesized CNPCs can be potentially applied as the reinforcing matrix. Moreover, the growth mechanism of CNPCs has also been proposed by investigating the effects of Co catalyst, thiophene promoter and gas-flow during the growth process. [ABSTRACT FROM AUTHOR]

• Protein isolate (PI) and purified polyphenol extract (PPE) were prepared from Cinnamomum camphora seed kernel. • Preheat treatment decreased the sulfhydryl group content and particle size of PI. • Preheat-treated PI exhibited more compact structure and higher thermal stability. • PPE modification changed the structure and conformation of PI. • PPE modification improved the antioxidant activity and thermal stability of PI. In this study, protein isolate (PI) and purified polyphenol extract (PPE) were prepared from Cinnamomum camphora seed kernel (CCSK). The effects of preheat treatment (50–90 °C) combined with polyphenol grafting (5 % PPE, w/w) on the structural, emulsifying and rheological properties of PI were investigated. Results demonstrated the preheat treatments at 80 and 90 °C significantly increased the extent of protein aggregation of PI. Fluorescence spectra and thermal behavior analysis revealed that preheat-treated PI exhibited more compact structure and higher thermal stability. Moreover, the emulsifying stability and apparent viscosity of PI were enhanced after preheat treatments at 50, 60 and 70 °C. After modification by PPE, the secondary structural changes of preheat-treated PI were confirmed by FTIR. PPE modification improved the thermal stability and antioxidant activities of preheat-treated PI. These results provide a novel way to combine the advantages of preheat treatment and polyphenol grafting in developing a novel protein ingredient. [ABSTRACT FROM AUTHOR]

Facilely tailored electrocatalyst with high-efficiency and durability for carbon dioxide (CO2) to carbon monoxide (CO) conversion is appealing but remains challenging. Herein, small nickel nanoparticles (about 19.4 nm) confined in nitrogen-doped carbon (Ni NPs@N–C) with narrow size distribution are successfully constructed via a facile one-step calcination strategy of Ni containing MOF compounds. By virtue of the protective N-doped graphitized carbon shell and the uniformly distributed fine Ni nanoparticles in a narrow range from 13 to 21 nm, the as-obtained Ni NPs@N–C can exclusively convert CO2 into CO with excellent Faradaic efficiency (FE) of 96.8% at − 1.0 V (vs. RHE), as well as the superior long-term catalytic stability over 24 h. Moreover, a high current density of more than 200 mA cm−2 with a stable CO FE of 92% can be achieved in a flow cell configuration. This work paves a new way for the facile and potentially scale preparation of small metal nanoparticles for efficient CO2- to-CO conversion. [ABSTRACT FROM AUTHOR]

Amyloid-like fibrils derived from plant proteins has provided a strategy to improve plant protein physicochemical performance and has substantial untapped potential for application in stabilizing oil-in-water (O/W) emulsions. This study aimed to explore the structural modifications of lentil protein fibrils (LPF) and their emulsifying properties facilitated by EGCG, with the proposal of potential underlying mechanism. The structure and morphology of LPF-EGCG complexes were characterized by particle size, Fourier transform infrared (FTIR) spectroscopy, fluorescence spectroscopy, surface hydrophobicity, contact angle, and transmission electron microscope (TEM). Results showed that the binding of LPF to EGCG was driven by hydrogen bonding and hydrophobic interaction. Both interactions play a pivotal role in the cross-linking of LPF and the transformation of the elongated fibrillar morphology of LPF into fibrillar aggregates networks, and even large-sized non-amyloid fibril aggregates, with particle size increasing from 564 nm to 3221 nm. Droplet size and confocal laser scanning microscopy (CLSM) results showed that the O/W emulsions containing 30% and 50% (w/w) oil stabilized by LPF-EGCG complex (EGCG-to-protein ratio, EGCG/P = 0.04) exhibited smallest and uniform droplet sizes (9.25 μm and 11.50 μm, respectively). The reason was that an appropriate concentration of EGCG can fine-tune the hydrophobic/hydrophilic balance and network structures of LPF, thus enhancing the stability of emulsions. Moreover, emulsions containing 30% (w/w) oil stabilized by LPF-EGCG complexes (EGCG/P > 0.02) exhibited rheological behavior similar to emulsions containing 50% oil stabilized by LPF alone, indicating potential applications in the production of fat reduced emulsion with desirable textures. These findings provide a new perspective on the structural remodeling of plant-based protein fibrils mediated by phenolic compounds, expanding their application in the production of fat-reduced emulsion-based food products. [Display omitted] • The binding of LPF to EGCG was driven by hydrophobic interaction and hydrogen bonding. • EGCG induced exposure of hydrophobic groups of LPF in a concentration-dependent manner. • EGCG remodeled LPF from fibrils aggregates into large non-amyloid fibril aggregates. • EGCG significantly improved the stability and texture of emulsions stabilized by LPF. [ABSTRACT FROM AUTHOR]

[Display omitted] • 1 wt%Pd/NiMoO 4 with different Pd dispersity were synthesized. • Hydrogen spillover process adjusts hydrogenation sites and acidic sites. • 56.3–84.1% yields of cyclopentanones were obtained over Pd/NiMoO 4 -Cl. • 65.4–85.2% yields of cyclopentanols were generated over Pd/NiMoO 4 -AC. • Adsorption configurations of reactants determine the reaction route. Upgrading bioderived furfurals (furfural, 5-hydroxymethylfurfural) to cyclopentanones (cyclopentanone, 3-hydroxymethylcyclopentanone) and cyclopentanols (cyclopentanol, 3-hydroxymethylcyclopentanol) is a representative bifunctional catalytic process in biomass conversion. Here, a class of Pd/NiMoO 4 catalysts (Pd/NiMoO 4 -Cl, Pd/NiMoO 4 -AC) with low Pd loading (1.0 wt%) and different Pd dispersion are synthesized. The hydrogenation active sites and acidic sites of catalysts were adjusted by a water-mediated hydrogen spillover process. 56.3–85.3% yields of cyclopentanones and 65.4–85.2% yields of cyclopentanols were obtained by hydrogenative ring-rearrangement route of furfurals over Pd/NiMoO 4 -Cl and Pd/NiMoO 4 -AC, respectively. Over-hydrogenated byproducts (tetrahydrofurfuryl alcohol, 2,5-bis(hydroxymethyl)tetrahydrofuran) with a yield above 54% were generated by a full hydrogenation route over Pd/C. The difference in catalytic performance is results from alteration of the adsorption configurations of reactants and the transformation of Lewis acid sites to Brønsted acid sites by hydrogen spillover. This work presents an effective strategy for governing reaction routes and enhancing bifunctional catalysis with a hydrogen spillover mechanism. [ABSTRACT FROM AUTHOR]

The study aimed to investigate the bioaccessibility and the stability of purified ethanol extracts (PEE) from Cudrania cochinchinensis roots, and the changes in antioxidant activity and enzyme inhibition activity and cytotoxicity by in vitro digestion. No compounds were lost during the gastrointestinal digestion (GID) process, 15 compounds were tentatively identified using UPLC-TOF-MS/MS technology, including five phenolic and ten flavonoid compounds. After the gastric digestion (GD), the bioaccessibility of phenolic and flavonoid compounds was 55.66% and 52.44%, respectively. After the intestinal digestion (ID), the bioaccessibility of phenolic and flavonoid compounds reduced to 39.70% and 33.36%, respectively. The gastrointestinal digestion (GID) decreased the bioaccessibility of phenolic compounds. All compounds were affected throughout the gastrointestinal digestion (GID), among which the more affected compounds were 4-hydroxybenzoic acid, eriodictyol-7-O-glucoside, resveratrol and 3,6,3',4'-tetrahydroxyflavone (compared with the peak intensity of the undigested PEE). Furthermore, there was a reduction in the antioxidant activity, inhibition activity against α-glucosidase and tyrosinase, and cytotoxicity toward HepG2 cells of the PEE after GID. There was a significantly positive correlation between the bioactivity and the total phenolic/flavonoid contents. The results showed that in vitro digestion had significant effects on the phenolic content and bioactivity. Although phenolic contents were decreased during GID, C. cochinchinensis roots is still a good source of bioactive compounds for the development of functional foods with health benefits. [ABSTRACT FROM AUTHOR]

Developing a highly selective catalyst to upgrade furfurals (5‐hydroxymethyl furfural and furfural) to cyclopentanones (3‐hydroxymethyl cyclopentanone and cyclopentanone) and tetrahydrofuran alcohols (2,5‐bishydroxymethyl tetrahydrofuran and tetrahydrofuran alcohol) is highly significant for biobased fine chemical synthesis. Here, a series of La2B2O7 (B=Ti, Zr, Ce) metal oxides, featuring the same chemical formula but different topological structures are fabricated. After Pd loading, the Lewis acidity and metal‐support interaction are well governed by the support type, which further affects the hydrogenation and acid‐catalyzed ability. A greater than 82 % yield of cyclopentanones is obtained via a hydrogenative ring rearrangement route over Pd/La2Ti2O7. However, Pd/La2Ce2O7 shows high catalytic efficiency for tetrahydrofuran alcohols with an approximately 80 % yield via a complete hydrogenation route. Additionally, the catalyst exhibits outstanding recycling performance and structural stability. This study presents an interesting design strategy for the selective preparation of cyclopentanones and tetrahydrofuran alcohols through the regulation of the adsorption mechanism. [ABSTRACT FROM AUTHOR]

We report the synthesis of a novel type of carbon-based nanostructure, which is composed of a string of carbon nanopearl chains (CNPCs) with a connection structure of carbon nanofibers using a chemical vapor deposition method. Regularly spaced, nanometer-sized balls of graphitic carbon are found on the amorphous nanofibers. The nanopearls have nanometer-sized spheres, bodies in diameter varying from tens of nanometers to hundreds of nanometers, with solid interiors. The chain connections have a length ranging from several nanometers up to micrometers between two nanopearls. The nanopearls connect each other by the nanofibers, thus forming a chain. The CNPCs have potential for use as reinforcing matrix to produce strong and tough carbon-based nanocomposites. [ABSTRACT FROM AUTHOR]

Enzymatic degradation has become the most promising approach to degrading organic ester compounds. In this study, Bacillus licheniformis NCU CS-5 was isolated from the spoilage of Cinnamomum camphora seed kernel, and its extracellular lipase was purified, with a specific activity of 192.98 U/mg. The lipase was found to be a trimeric protein as it showed a single band of 27 kDa in SDS-PAGE and 81 kDa in Native-PAGE. It was active in a wide range of temperatures (5–55 °C) and pH values (6.0–9.0), and the optimal temperature and pH value were 40 °C and 8.0, respectively. The enzyme was active in the presence of various organic solvents, metal ions, inhibitors and surfactants. Both crude and purified lipase retained more than 80% activity after 5 h in the presence of commercial detergents, suggesting its great application potential in detergent industry. The highest activity was found to be towards medium- and long-chain fatty acids (C 6 -C 18). Peptide mass spectrometric analysis of the purified lipase showed similarity to the lipase family of B. licheniformis. Furthermore, it degraded more than 90% 2,4-D butyl ester to its hydrolysate 2,4-D within 24 h, indicating that the novel lipase may be applied to degrade organic ester pesticides. • A lipase-producing strain B. licheniformis NCU CS-5 was firstly isolated. • A novel alkaline, cold adaptive and organic solvent tolerant lipase was purified. • The lipase preferred triacylglycerols with medium- and long-chain fatty acids. • The lipase was stable in commercial detergents at 5 °C and 25 °C. • The lipase efficiently degraded 2,4-D butyl ester. [ABSTRACT FROM AUTHOR]

Efficient synthesis of large-scale vertically aligned nitrogen-doped carbon nanotube arrays (VA-NCNTs) has always been a challenge. In this study, we proposed a facile way to obtain mass VA-NCNTs between vermiculite layers by horizonal chemical vapor deposition (CVD). Vermiculite with layered compound as the catalyst substrate, Fe and Mo as the active metal phase is evenly distributed between the vermiculite layers, melamine is pyrolyzed as a single source for both carbon and nitrogen to synthesize nitrogen-doped carbon nanotube (CNT) array materials with relatively uniform length and diameter at an optimum temperature of 800 °C. We explored the effect of temperature on synthesis of VA-NCNTs, the results indicated that the VA-NCNTs are sensitive to temperature changes during the CVD synthesis process, the arrangement, diameter, nitrogen content, and the type of nitrogen function of CNTs could be modified. This work contributes to the study of how the growth temperature affecting the morphology of the as-prepared CNTs, and provides a potential method for the controllable mass production of oriented NCNTs. [ABSTRACT FROM AUTHOR]

The interaction mechanism of a kind of natural drug helicid with typical digestive enzyme trypsin was investigated using multi-spectroscopic techniques and molecular modeling method. The fluorescence quenching experiments showed that helicid quenched trypsin fluorescence via a combined quenching mechanism of both dynamic and static quenching processes because of the formation of the helicid–trypsin complex. Thermodynamic analyses suggested that the binding of helicid to trypsin was entropy-driven, and that hydrophobic interactions are the main force to stabilize the complex. Förster energy transfer theory applied demonstrated that energy transfer occurred within the complex. Ultraviolet-visible spectroscopy, synchronous fluorescence spectroscopy, three-dimension fluorescence spectroscopy together with circular dichroism spectroscopy indicated that the conformation of trypsin changed induced by helicid with the loosening of the polypeptide backbone of trypsin and its partial β-sheet and random coil structures being transformed into an α-helix structure and that helicid was closer to tryptophan residues than to tyrosine residues within the complex. Molecular simulation results explained the above experimental results very well and further implied that besides hydrophobic interactions, hydrogen bonds also helped stabilize the helicid–trypsin complex. This study is helpful to the understanding of the biochemical process of helicid in the human body and could provide useful information for the studies on the structure–bioactivity relationship of natural compounds, as well as the design and optimization of the drugs for the treatments of trypsin overactivity-related diseases. [ABSTRACT FROM AUTHOR]

Developing a powerful bifunctional catalyst for tandem reactions is essential to the future carbon neutrality by reducing the energy consumption in chemical industries. Herein, mesoporous zeolite-encapsulated palladium (Pd) nanoparticles (Pd@meso-ZSM-5) synthesized via emulsification-demulsification followed by a dry-gel transformation method were demonstrated to have a remarkable catalytic performance for a one-pot multiple tandem reaction of cyclic ketones (cyclopentanone, cyclohexanone) to bicyclic alkanes (bicyclopentane, bicyclohexane). Compared with supported catalysts (Pd/meso-ZSM-5) and microporous zeolite-encapsulated catalysts (Pd@ZSM-5) with a primary product of monocyclic alkane (cyclopentane, cyclohexane), Pd@meso-ZSM-5 shows much higher catalytic efficiency for the bicyclic alkanes synthesis, which was previously unattainable in the conventional two-step synthesis route. Controlled experiments and detailed characterizations show that mesoporosity provides sufficient space for the generation and diffusion of large molecular intermediates, and the intimate acid-Pd interface promotes the conversion of intermediates. This work proposes a design strategy for a mesoporous zeolite-encapsulated metal catalyst, which efficiently provides cooperative acid-hydrogenation catalysis. [Display omitted] • Mesoporous zeolite-encapsulated Pd nanoparticle was fabricated. • Bicyclic alkanes were obtained from cyclic ketones by one-pot tandem reaction. • Mesoporosity ensures sufficient space for intermediate generation. • Intimate acid-Pd interface promotes intermediate conversion. • The catalyst shows excellent recycling stability. [ABSTRACT FROM AUTHOR]

In this study, the antibacterial activity of monocaprin against Gram-negative foodborne pathogens and its underlying mechanism against E. coli were investigated. It was found that monocaprin exerted excellent antibacterial effects on E. coli , Vibrio parahaemolyticus and Shigella dysenteriae with the minimum inhibitory concentration/minimum bactericidal concentration values of 1.25 mM, 0.625 mM and 0.625 mM, respectively. The results of growth curve and time-kill assay showed that monocaprin could not only delay the growth of E. coli , but quickly inactivate the cells within 15 min. The effects of monocaprin on membrane integrity, inner and outer membrane permeability, proton motive force, and its interaction with model membranes and cell morphology were investigated to explore the antibacterial mechanism of monocaprin. The results indicated that monocaprin rapidly inactivated E. coli by penetrating its outer membrane, then destroying the phospholipid bilayer structure of the inner membrane, as well as dissipating the proton motive force, resulting in increases of the permeability of the outer and inner membranes and leakage of intracellular substances. Besides, monocaprin significantly reduced the viability of E. coli in apple and carrot juices at 4 °C and 25 °C without changing their sensory properties. • Monocaprin effectively inhibited E. coli , V. parahaemolyticus and S. dysenteriae. • Monocaprin rapidly inactivated of E. coli within 15 min by targeting cell membrane. • Monocaprin destroyed cytoplasmic membrane and dissipated the proton motive force. • Monocaprin increased the inner and outer membrane permeability of E. coli. • Monocaprin may be useful as a potent preservative for preventing E. coli in apple and carrot juices. [ABSTRACT FROM AUTHOR]

Developing efficient, selective, and stable single-atom electrocatalysts for CO 2 reduction reaction (CO 2 RR) is attractive but still remains a challenging, especially for scalable production with low-cost. Among the non-precious metal single-atom electrocatalysts, Cu single-atom electrocatalysts are rarely explored for the efficient CO 2 -to-CO conversion. Herein, we reported a facile and scalable strategy to prepare the Cu single-atom catalyst (Cu SAs/NC) with exceptional CO production performances. Atomically dispersed Cu–N 4 moieties are unambiguously verified by HAADF-STEM and XANES measurements. The as-prepared Cu SAs/NC catalyst delivers a high CO faradaic efficiency of 92% at −0.7 V RHE as well as the excellent durability over 30 h successive electrolysis. It should be noted that this is one of the rare examples of efficient CO production on Cu single-atom electrocatalyst. Besides, the 20-g + samples can be readily fabricated in one batch and exhibit the almost identical CO 2 RR performances. Furthermore, the combined experimental and theoretical calculation results identify the genuine active Cu–N 4 sites are responsible for the high selectivity and efficiency of CO production. This work provides a novel strategy for scalable single-atom electrocatalysts in stable quality and offers new insights into the efficient CO 2 -to-CO conversion on Cu single-atom electrocatalyst. Gram-quantities of earth-abundant Cu single-atom anchored on N-doped porous carbons were synthesized via a facile and scalable method. The as-prepared catalyst exhibits exceptional CO 2 electroreduction to CO performance. The atomically dispersed Cu–N 4 structures are responsible for the highly efficient, selective and stable CO production. Image 1 • Scalable and low-cost production method to prepare Cu single-atom catalysis. • A rare example of Cu–N–C catalyst for efficient CO2-to-CO conversion. • High CO faradaic efficiency of 92% at −0.7 V RHE and stability over 30 h. • Mechanisms of high CO selectivity and activity on Cu–N4 sites. [ABSTRACT FROM AUTHOR]

The objective of this study was to investigate the antioxidant and enzyme inhibitory activity, and characterize the bioactive constituents of the phenolic extract of Potentilla discolor Bge. Dry material of Potentilla discolor Bge. was extracted with 80% ethanol solution to obtain the crude phenolic extract (CPE) with the total phenolic content (TPC) of 20.40 ± 0.69 mg of gallic acid equivalents per gram of dry material (mg GAE/g DM). After purified with AB-8 macroporous resin, TPC of the purified phenolic extract (PPE) (353.65 ± 5.50 mg GAE/g DM) was much higher than that of the CPE. PPE exhibited stronger 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity and 2,2′-azino-bis 3-ethylbenzothiazoline-6-sulfonic acid (ABTS) radical scavenging activity than CPE and 2,6-Di-tert-butyl-4-methylphenol (BHT), with the IC50 values of 0.030 ± 0.002 mg/mL and 0.059 ± 0.002 mg/mL, respectively. The total antioxidant activities of PPE and BHT were similar, and were higher than CPE. PPE was found to significantly inhibit α-amylase and α-glucosidase with IC50 values of 0.966 ± 0.072 and 2.431 ± 0.088 mg/mL, respectively. Finally, using UPLC-TOF–MS/MS technology, 35 compounds were tentatively identified, including 12 phenolic acids, 23 flavonoids and their derivatives, 29 of which have been discovered for the first time in Potentilla discolor Bge. These results suggested that PPE had the potential to be used as an antioxidant and anti-diabetic component in functional foods. [ABSTRACT FROM AUTHOR]

Drug‐induced liver injury (DILI) is one of the common adverse effects of drug therapy, which is closely associated with oxidative stress, apoptosis, and inflammation response. Medium‐chain fatty acids (MCFA) were reported to relieve inflammation and attenuate oxidative stress. However, little has been known about the hepatoprotective effects of MCFA in DILI. In the present study, acetaminophen (AP) and rifampicin (RFP) were used to establish DILI models in LO2 cells, and the cytoprotective effects of MCFA on hepatocellular injury were investigated. Results showed that the optimal condition for the DILI model was treatment with 10 mM AP or 600 µM RFP for 24 hr. LCFA treatment markedly reduced the cell viability and increased the activities of alanine aminotransferase, aspartate aminotransferase, and lactate dehydrogenase. Meanwhile, LCFA treatment aggravated cell apoptosis, mitochondrial dysfunction, and oxidative stress. The mRNA and protein expression levels of inflammatory cytokines (IL‐1β and TNF‐α) were significantly elevated by LCFA. In contrast, MCFA treatment did not significantly affect cell viability, apoptosis, oxidative, stress and inflammation, and it did not produce the detrimental effects on DILI models. Therefore, we proposed that MCFA may be more safe and suitable than LCFA as nutrition support or the selection of daily dietary oil and fat for the patients with DILI. [ABSTRACT FROM AUTHOR]

Developing highly efficient heterogeneous catalysts for cycloaddition of CO2 and epoxides to produce cyclic carbonates is promising but challenging. In this work, a novel three-dimensional metal organic framework (MOF) with cylinder pore systems and unsaturated Zn sites has been demonstrated as potent candidate in CO2 fixation at mild and solvent-free conditions. The Zn(atz)(bdc)0.5, where atz = aminotriazole and H2bdc = terephthalic, exhibits microporous nature that can regulate the catalytic interaction of active centers and substrates. The structure stability has been systematically investigated and proven to be sufficient for practical application. Furthermore, the cooperative effects of porosity, CO2 binding affinity, activation centers, and synergism with co-catalyst have been deeply investigated. Moreover, high propylene epoxide conversion (97%) and selectivity (> 99%) have been achieved at mild conditions (60 °C and 1 MPa) with excellent cycle stability. Owing to the well-defined pore system, an obvious substrates selectivity has been clearly observed. A possible catalytic mechanism has been proposed and verified by DFT calculations. Furthermore, the prepared Zn-MOF can also be used as an efficient heterogeneous catalyst for the reaction of epoxides with alcohols to produce β-alkoxy alcohol. [ABSTRACT FROM AUTHOR]

The major challenge in the synthesis of high-density biofuels is to identify the bio-based source for C–C cyclic compounds and C–C coupling reactions with a suitable selectivity. Herein, we selectively synthesize 1,2,4-benzenetriol (BTO) with a yield of 51.4% from cellulose-derived 5-hydromethylfurfural via a ring-rearrangement reaction. The cellulose-derived route is a more meaningful route for the C–C cyclic compounds compared to the traditional hemicellulose- and lignin-derived routes. Furthermore, BTO is very easily dimerized via a C–C oxidative coupling reaction, showing a yield of 94.4% and selectivity of nearly 100% under environmentally friendly reaction conditions. After hydrodeoxygenation, bicyclohexane is obtained with a yield of 87.4%. This work not only provides a promising route to produce C–C cyclic fine compounds based on a cellulose-derived route, but also shows a highly efficient synthesis route for high-density biofuels via the C–C oxidative coupling reaction. [ABSTRACT FROM AUTHOR]

Herein, novel green synthetic routes to 4-hydroxy-2-cyclopentenone (HCP) and 2-cyclopentenone (CPE) from biomass-derived furfuryl alcohol via double-metal cyanide catalysis are proposed. For the synthesis of HCP, in comparison to conventional solid acids (i.e., Amberlyst-15), MOFs with coordinatively unsaturated metal ions as pure Lewis acid sites exhibit advantageous catalytic selectivity in the reaction under an N2 atmosphere in a bi-phasic water/n-hexane solvent system. FeZn and FeZn-P result in an HCP yield of 77.4% and 88.2%, respectively. For the CPE synthesis, the reaction conditions are the same as those for HCP, except a mono-phasic water solvent system and H2 atmosphere were employed. In addition to the acid-catalyzed rearrangement reaction, FeZn-DMC exhibits catalytic hydrogenation capability via heterolytic cleavage of the H–H bond over Zn–N frustrated Lewis pairs, and a CPE yield of 61.5% is obtained. The DFT simulation indicates that the acid sites and catalytic acid sites are ascribed to the tri-coordinatively unsaturated Zn2+ site (Zn(N)3) on the catalyst surface. Moreover, the DMC catalyst shows excellent stability and recycling performance. This work not only provides an efficient and green catalytic system for CPE and HCP preparation but also demonstrates the interesting bifunctional catalysis of both acid and hydrogenation catalysis over DMC. [ABSTRACT FROM AUTHOR]

High-energy-density and flexible supercapacitors have shown numerous application potential in modern portable electronics. However, the relatively low specific capacity, poor rate retentions, and limited durability have hindered their implement. Herein, a novel hierarchical dual-hollow electrode, composed of a hollow Ni 2 CoS 4 sphere and outer hollow Ni 2 CoS 4 nanotubes (Ni 2 CoS 4 HS-HTs), is elaborately constructed. The Ni 2 CoS 4 HS-HT-5 exhibits a high specific capacity of 817.5 C g−1 at a current density of 1 A g−1 with remarkable rate retention of 75.3% at 50 A g−1. In an all-solid-state asymmetric supercapacitor of Ni 2 CoS 4 HS-HT-5//CAC, a high capacitance of 1511.5 mF cm−2 at 5 mA cm−2 is obtained with an exceptional energy density of 13.6 mWh cm−3 at a power density of 92.6 mW cm−3. In addition, the capacity retention reaches 96% over 2000 cycles at 20 mA cm−3, implying the outstanding durability. The flexibility and mechanical stability are demonstrated by the intact electrochemical performances under different bending angles. As a proof-of-concept, two Ni 2 CoS 4 HS-HT-5//CACs in series could successfully illuminate 31 LED indicators for more than 8 mins. These fascinating electrochemical performances benefit from the novel electrode structure and depict great potential for modern energy storage applications. [ABSTRACT FROM AUTHOR]

The composites consisting of nitrogen-doped carbon nanotubes (N-CNTs) and nitrogen-doped carbon nanofibers (N-CNFs) were fabricated using a mixture of nickel foam (template) and imidazole (solid precursor) in a facile one-step chemical vapor deposition (CVD) process. The morphology and microstructure of the N-doped carbon nanotubes/N-doped carbon nanofibers hierarchical composites (N-CNTs/N-CNFs) were determined by scanning electron microscopy, transmission electron microscopy, X-ray diffraction, Raman spectra, and X-ray photoelectron spectroscopy. The results indicated that the sample manifests regular hierarchical composites, great graphitization, and nitrogen doping. Furthermore, a probable growth mechanism is presented to analyze the composites. [ABSTRACT FROM AUTHOR]

• Pure Lewis DMC-based bifunctional catalysts with controllable acidities were synthesized. • Pd/FeZn showed moderate acidity, Pd/FeNi and Pd/FeCo have weak acidity. • Furanic aldehydes were efficiently converted to cyclopentanones compounds over Pd/FeZn. • High yield of furanic alcohols is obtained from furanic aldehydes over Pd/FeNi and Pd/FeCo. The hydrogenative ring-rearrangement of biomass-derived furanic aldehydes (furfural or 5-hydroxymethyl furfural) to cyclopentanone compounds (cyclopentanone or 3-hydroxymethyl cyclopentanone) is of great significance for high-value chemicals. The Brønsted acid in metal-support bifunctional catalysts causes a serious carbon loss, and the weak Lewis acid is difficult to induce hydrolysis reaction steps. Here, a double-metal cyanide (DMC) catalyst with pure moderate Lewis acid sites was investigated for solving the above problems. The crystal structure and the Lewis acidity of the catalyst are controlled by different kinds of metals, and the surface properties are changed by a complexing effect. Pd clusters of 8 nm are uniformly dispersed on the surface after impregnation on the double-metal cyanide. For the reaction of furanic aldehydes, the Pd/FeZn-DMC catalyst with a moderate Lewis acidity shows a high efficiency for the synthesis of cyclopentanone compounds, whereas the Pd/FeNi-DMC and Pd/FeCo-DMC catalysts with a weak Lewis acidity result in a yield above 90.2% of furanic alcohols (furfuryl alcohol or 2,5-bis(hydroxymethyl)furan). The catalytic activity of Pd/FeZn-DMC is controlled by the surface area based on the accessibility of the Lewis acid sites, and the highest yields of 96.6% and 87.5% are obtained for cyclopentanone and 3-hydroxymethyl cyclopentanone, respectively. Furthermore, the catalyst is resistant to leaching and performs stably after 6 runs. This study not only provides a promising route for efficient production of cyclopentanone compounds but also shows the excellent advantage of DMC-based bifunctional catalysis in biomass conversion reactions. [ABSTRACT FROM AUTHOR]

Schematic of the CVD process used for N-doped carbon microspheres synthesis in the presence of melamine as both the nitrogen and carbon precursor. • Integration of sphere-like carbon and nitrogen doping into a single entity. • Melamine as both carbon precursor and N-dopant. • Ferrocene as both catalyst and carbon precursors. • Water-assisted chemical vapor deposition. N-doped carbon hollow microspheres (NCMs) have been prepared by a facile water-assisted chemical vapor deposition (CVD) process using melamine as both the carbon precursor and N-dopant and ferrocene as both the catalyst and carbon precursor. It is shown that the size of the NCMs can be tuned just by changing the annealing temperature of the CVD furnace. The atomic percentage of nitrogen doping in NCMs could be achieved to 7.85% without sacrificing the hollow spherical structure. Probable growth mechanism of NCMs was proposed in this paper. The work reported here may pave a way for designing novel various atom-doped carbon microspheres. [ABSTRACT FROM AUTHOR]

N-doped well-aligned thin multiwall carbon nanotubes (CNTs) have been prepared by a facile water-assisted chemical vapor deposition (CVD) process using melamine as both the carbon precursor and N-dopant and ferrocene as both the catalyst and carbon precursor. It is shown that the synthetic temperature has strong effects on the growth of carbonaceous structure. Carbon films started to grow at reaction temperature of 700 °C, and the optimal temperature for the synthesis of aligned CNTs, based on the experiment results, was found to be 900 °C. The lengths of the CNTs can be tuned by changing the annealing time of the pyrolysis process, it could reach as long as 40.2 μm. The atomic percentage of nitrogen doping in aligned CNTs could be achieved to 1.71%. It was found that there were many joints and defects in the as-prepared CNTs which may offer more nucleation sites on the chemically inert CNT surface for various specialized applications such as supercapacitor. [ABSTRACT FROM AUTHOR]

Salmonella spp., one of the most frequently reported bacteria, causes foodborne illness and economic losses. Due to the threat of increasing antibiotic resistant foodborne pathogens, application of bacteriophages as novel antibacterial agents in food matrices has become an emerging strategy. In this study, a novel Salmonella phage PS3-1 with high lytic activity against Salmonella Typhimurium was identified from previously isolated phages. PS3-1 belonged to the class Caudoviricetes with a broad host range, and had relatively short latent period (15 min), large burst size (92 PFU/cell), high pH stability (pH 3.0–11.0) and thermal tolerance (4–60 °C). Genome sequencing analysis showed that PS3-1 genome consisted of 107,110 bp DNA, without antibiotic resistance and virulence related genes. The results of growth curve and time-kill assay showed that PS3-1 not only inhibited the growth of S. Typhimurium , but also effectively decreased the viable cell counts (0.30–4.72 log) after 24-h incubation at 7, 25 and 37 °C (P < 0.05). Moreover, >1.28 log of established biofilm cells were effectively removed after 24-h treatment with PS3-1. Besides, PS3-1 significantly reduced the viability of S. Typhimurium in milk, lettuce, raw pork meat and ready-to-eat steamed-chicken breast at different temperatures (P < 0.05). These results demonstrated that PS3-1 may be an excellent antibacterial agent for controlling S. Typhimurium in food industry. • Siphoviridae phage PS3-1 showed a rapid and strong lytic activity against Salmonella. • PS3-1 showed great pH tolerance and thermal stability. • PS3-1 significantly removed the S. Typhimurium biofilms with a maximum reduction of 1.52 log at 7 °C. • PS3-1 effectively reduced S. Typhimurium counts in milk, lettuce, raw pork meat and RTE steamed-chicken breast. [ABSTRACT FROM AUTHOR]

Benefiting from the ultrahigh specific surface area, tunable pore size, and abundant surface functionality, biomass derived carbons (BC) are thriving as promising conductive matrices to host sulfur for Li S battery cathodes. Unfortunately, pristine BC still suffers from awful cycling performance rooted in their limited physical/chemical adsorption ability towards polysulfide. Herein, we proposed to construct Nickel Aluminum Layered Double Hydroxides (NiAl-LDH) fences coated on H 3 PO 4 activated BC (PAB) as an efficient sulfur host. The decorated NiAl-LDH fences could efficiently reinforce both chemical adsorption and physical confinement effects on polysulfides, and render as an electrocatalyst to significantly boost the redox reaction kinetics. Furthermore, the DFT simulation has been employed to illustrate enhanced interaction forces towards polysulfides. As a result, the prepared NiAl@PAB/S cell exhibits an improved performance of 1216.3 mAh g−1 initially at 0.2C (1C = 1672 mAh g−1), excellent cycling stability during 300 cycles at 1 C (0.13% decay rate per cycle), and superior rate capability up to 3 C (614.2 mAh g−1). This work provides a cost-efficient and effective method to significantly improve the overall performance of porous-carbon-based Li S battery cathode. [ABSTRACT FROM AUTHOR]

• A sulfonated biochar is prepared by sulfonation method of 4-chlorobenzenesulfonic acid. • The sulfonated biochar have a strong hydrophobic network and acid density. • The catalyst is highly active for the esterification reactions. • The catalyst is active and selective for alkylation reactions. • The catalyst is stable for five runs. Catalytic esterification of fatty acid with methanol, alkylation of 4-ethylphenol with benzyl alcohol as well as 2-methylfuran with cyclopentanone are of great significant for the production of biofuels. However, the in-situ produced water decreases the acidity of catalyst and induces side reaction, leading to an unsatisfactory catalytic activity and selectivity. Herein, a novel biochar-based hydrophobic benzenesulfonic acid is prepared for the first time by one-pot sulfonation method of biochar with 4-chlorobenzenesulfonic acid. It has a large specific surface area of 100-400 m2/g, a hydrophobicity with H 2 O contact angle higher than 110° and a high concentration of sulfonic acid over 1.0 mmol/g. In the esterification reaction of fatty acid with methanol for synthesis of biodiesel, it shows a higher conversion of 96.0% than sulfonic acid resin amberlyst-15 (86.7%) and traditional sulfonated biochar-SO 3 H (28.0%). In the alkylation reaction of 4-ethylphenol with phenylmethanol/2-methylfuran with cyclopentanone for high-density bicyclic/monocyclic biofuel, its catalytic efficiency with target product yields are 69.4% and 70.5% respectively, which are also higher than that of amberlyst-15 (74.3%, 49.4%) and biochar-SO 3 H (14.7%, 13.0%). Furthermore, the catalyst is more stable than biochar-SO 3 H. The preparation of hydrophobic biochar-based sulfonic acid catalysts not only opens a new way for high-value utilization of biochar, but also provides a novel efficient catalyst in many acid-catalyzed transformation reactions that the product H 2 O causes deleterious effects. [ABSTRACT FROM AUTHOR]

Abstract In this study exopolysaccharide (EPS) of Enterococcus faecium WEFA23 from healthy infant's feces was yielded as high as 130 mg/L by fermentation. By purification the EPS was further fractioned into A23-1, A23-2, A23-3 and A23-4 on HiTrap Q HP and Superdex G-200 column. As the major purified fractions, A23-2 and A23-4 were analyzed for the preliminary structures and investigated for the biological properties in vitro. The molecular weight of A23-2 and A23-4 was 2.50 × 104 Da and 3.23 × 104 Da, respectively. A23-2 was composed of mannose, glucose and galactose with a ratio of 1.38:1.00:1.42, while A23-4 consisted of only mannose. The antioxidant ability of A23-2 was significantly higher than that of A23-4, as proved by scavenging test of DPPH radical, hydroxyl radical and superoxide radical. Both A23-2 and A23-4 exhibited strong inhibition against the adhesion of L. monocytogenes CMCC54007 on HT-29 cells no matter for the styles of competition, displacement and exclusion. Notably, for exclusion they had a maximal inhibition rate of 89.85 ± 0.46% and 90.81 ± 2.29%, respectively, at 200 μg/mL. Highlights • Novel exopolysaccharide from Enterococcus faecium WEFA23 was isolated and purified which includes four fractions, i.e. A23-1, A23-2, A23-3 and A23-4. • A23-2 was heteropolysaccharide composed of mannose, glucose and galactose, while A23-4 was homopolysaccharide consisted of mannose. • Both A23-2 and A23-4 exhibited free radicals scavenging capacities in vitro, and A23-2 showed higher antioxidant activity than A23-4. • A23-2 and A23-4 exhibited strong inhibition on adhesion of L. monocytogenes CMCC54007 to HT-29 cells. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Pd/Fe-MIL-100 shows higher activity of and selectivity than Cr-MIL-101 and Fe-MIL-101. • Pd-based catalysts is more active and selective than Ru, Pt and Au. • The catalysts are highly efficient for both furfural and 5-hydromethylfurfural. • The catalysts are stable and recyclable. Abstract Hydrogenative ring-rearrangement reaction of biomass-derived furanic aldehydes to cyclopentanone compounds catalyzed by metal/support bifunctional catalysts suffers a low selectivity of target product and serious carbon loss because of the Brønsted acid catalysis. Herein, a series of pure Lewis acid sites MIL-MOFs (Fe-MIL-100, Fe-MIL-101 and Cr-MIL-101) with different crystal topology structures and metals are synthesized. Then the nanoparticles of Ru, Pt, Pd and Au are uniformly dispersed on the internal surface of the MOF support. The hydrogenation rate catalyzed by the noble metals/Fe-MIL-100 is three times faster than those obtained with Fe-MIL-101 and Cr-MIL-101-based catalysts due to the higher dispersion of nanoparticles on the former to make it more accessible to reactants. Meanwhile, both of the noble metals on Fe-MIL-100 and Fe-MIL-101 have a higher selectivity of cyclopentanone compounds than that on Cr-MIL-101, since the Fe ions in the MOF host with a higher oxophilicity will promote the adsorption and hydrolysis of the intermediate furanic alcohols (furfural alcohol or 2,5-bis(hydroxymethyl)furan). Furthermore, the noble metals/MIL-MOFs catalyst can maintain a good activity and stability after recycling for five runs. The current work will present an efficient catalytic reaction system for the hydrogenative ring-rearrangement of furfural and 5-hydroxymethyl furfural to synthesize cyclopentanone compounds. [ABSTRACT FROM AUTHOR]

Graphical abstract Sulfonic acid functionalized biochar with hydrophobic network and high-concentration sulfonic acid is obtained by diazonium reduction method. Highlights • A sulfonated biochar was prepared by diazo reduction grafting of amino-arenesulfonic acid. • The novel sulfonated biochar have a strong hydrophobic network and high acidity. • The hydrophobicity and acidity is increased with the length of arene. • The catalyst was active and stable for the esterification and transesterification reactions. • The catalyst was active and selective for alkylation of 2-methylfuran with cyclopentanone. Abstract Sulfonic acid functional strong acidic catalysts are largely used in various chemical reactions. However, in many reactions with water as product, the catalytic activity and selectivity are unsatisfactory, because hydrophilic acid sites of SO 3 H would suffer from acidity decreasing and some hydrolysis side reactions would occur via water adsorption. Herein, a novel hydrophobic arenesulfonic acid functionalized biochar was successfully prepared for the first time by one-pot diazo reduction method of biochar with amino-arenesulfonic acid (such as, 4-aminbenzenesulfonic acid, 4-amino-1-naphthalenesulfonic acid, 8-amino-1-naphthalenesulfonic acid, 4-amino-3-hydroxy-1-naphthalenesulphonic acid). It has a large specific surface area of 200–400 m2/g, a hydrophobic network with water contact angle higher than 120° and a higher concentration of sulfonic acid over 1.0 mmol/g. Moreover, the hydrophobicity-oleophilicity and acidity are increased with the arene length and grafting amount of arenesulfonic acid. In the esterification reaction of fatty acid with methanol as well as the transesterification reaction of glycerol trioleate with methanol for the production of biodiesel, the sulfonated biochar shows a higher conversion of 96.7% for esterification and 86.3% for transesterification compared with amberlyst-15 (86.7%, 39.9%) and traditional sulfonation biochar-SO 3 H (27.4%, 32.6%). In the alkylation reaction of 2-methylfuran with cyclopentanone for the production of high-density biofuel, its catalytic efficiency with target product yield of 76.1% is higher than that of amberlyst-15 (50.2%) and traditional sulfonation biochar-SO 3 H (13.2%), because of its hydrophobicity and strong acidity. Furthermore, the catalyst is stable and shows an excellent cycle performance after 6 runs. The successful preparation of hydrophobic biochar-based acidic catalysts not only provides a new way for high-value utilization of biochar, but also eliminates the negative effect of water on many catalytic reactions. [ABSTRACT FROM AUTHOR]

We report here the one-step water-assisted CVD growth of metal oxide nanosheets/carbon nanotubes (CNTs) composites. The cross-linked composites were characterized by scanning electron microscopy, transmission electron microscopy, and Raman spectroscopy. The results showed that helical CNTs were obtained when the CVD growth process was prolonged to 1 h, and the typical fish-bone-type CNTs can be observed by HRTEM. Moreover, a related growth mechanism is proposed to explain the growth of such novel nanocomposites. [ABSTRACT FROM AUTHOR]

Graphic abstract This work presents a facile and efficient one-pot melting-assisted and solvent-free method to prepare low-cost N-rich polymer SFRH. Furthermore, the polymer derived N-enriched porous carbon could be used for highly selective mixed-gas separation, CO 2 storage and PSA. Highlight • Facile one-pot and solvent-free method to preparation. • N-doped porous carbons. • Outstanding gas mixture selectivity. • Excellent pressure/vacuum swing adsorption (P/VSA) working capacity. • 10-fold scaled up production. Abstract A facile one-pot melting-assisted and solvent-free method was successfully developed for the first time for preparing nitrogen-containing polymers. Followed by activation at temperatures ranging from 600 to 800 °C led to the formation of N-rich microporous carbons possessing narrow pore size distribution (ca. 0.5–3 nm), high specific surface area (ca. 1021.4–3657.0 m2 g−1), large pore volume (ca. 0.43–2.00 cm3 g−1) and high nitrogen content (ca. up to 5.11 wt%). Particularly, the porous carbons exhibited outstanding CO 2 adsorption capacity of 2.65 and 7.38 mmol g−1 at 273 K and 0.15 and 1 bar, respectively; meanwhile, it also exhibited extremely large CO 2 storage capacity of 22.06 mmol g−1 at 298 K and 20 bar. Moreover, the outstanding CO 2 /N 2 , CO 2 /CH 4 and CH 4 /N 2 selectivity up to 36.5, 6.9 and 5.1 at 298 K and 1 bar were achieved. The determinant factors on CO 2 capture at 0.15, 1 and 20 bar were carefully investigated. Furthermore, this method could be 10-fold scaled up to produce almost identical high-performance carbons. For real-world applications, pressure/vacuum swing adsorption (P/VSA) working capacity, gas-mixture transit breakthrough experiment, and recycle feasibility are evaluated. Thus, these novel materials are promising candidates for CO 2 capture from dilute gas mixtures. [ABSTRACT FROM AUTHOR]

Graphical abstract A novel bifunctional nanocomposites of LDHs@PAB exhibited effective and simultaneous removal for Cr(VI) and MO. Highlights • Acicular nanoflakes of Ni/Al LDH successfully decorated biomass-based porous carbons. • Ni/Al@PAB can simultaneously remove Cr(VI) and MO from the binary system. • The synergistic effect of PAB and Ni/Al LDH endows simultaneous and efficient removal. Abstract Layered double hydroxides (LDHs) are currently attracting intense research interests as pollutant adsorbent due to its low cost, non-toxicity, structure amenability and anion exchange capability. Herein, 3-dimensional (3D) flower-like Ni/Al LDH were prepared to decorate H 3 PO 4 activated biomass-derived porous carbons (PAB) via a facile and green hydrothermal method. The as-synthesized nanocomposites (Ni/Al@PAB) displayed favorable removal performance towards both Cr(VI) and methyl orange (MO) from aqueous solution due to the inherited excellent Cr(VI) removal ability from PAB and MO removal ability from Ni/Al LDH. In single-component removal system, the maximum adsorption capacity of 271.5 and 412.8 mg/g for Cr(VI) and MO were achieved on Ni/Al@PAB, respectively. Remarkably, the removal capacity of Cr(VI) and MO both increased in the Cr(VI) MO binary system due to the synergistic effect including, (i) additional adsorption sites of N-containing groups from MO, (ii) electrostatic interactions by the reduced Cr(III), and (iii) mutual thermal compensation in the binary system. This work paved the way for designing novel LDHs-decorated porous carbon adsorbents and revealed that the acicular Ni/Al LDH decorated PAB could be applied as efficient and simultaneous adsorbent for coexisting toxic pollutants situations. [ABSTRACT FROM AUTHOR]

It is notably challenging to fabricate controllable heteroatom-doped porous carbons for both highly effective mixed-gas separation and supercapacitor electrodes. In this work, novel algae-derived nitrogen-containing porous carbons were prepared as bifunctional materials. The pore structure of obtained carbons could be easily tailored by altering activation temperature or porogen/biomass ratio. The as-prepared porous carbon has a very high specific surface area of 1538.7 m 2  g −1 and a large pore volume of 0.99 cm 3  g −1 with a high N content of 2.77 wt%. As a solid-state adsorbent, the algae-derived carbon has an excellent CO 2 adsorption capacity of 5.7 and 3.9 mmol g −1 at 273 and 298 K, respectively. The extraordinarily high CO 2 /N 2 , CO 2 /CH 4 , and CH 4 /N 2 selectivity are demonstrated by the ideal adsorption solution theory (IAST) calculation and dynamic adsorption breakthrough experiments. As an electroactive material, the porous carbon exhibits outstanding capacitive performance in 6 M KOH aqueous electrolyte, with the specific capacitance of 287.7 and 190.0 F g −1 at 0.2 A g −1 in a three- and two-electrode system, respectively. Furthermore, the obtained carbon shows outstanding rate capability of 79.3% at 10 A g −1 and unprecedented cycling stability with 98% capacitance retention at 10 A g −1 after 8000 cycles as coin cell. This report introduces a biomass-derived and low-cost pathway to design porous carbon materials for efficient solid adsorbents and supercapacitive electrode materials. [ABSTRACT FROM AUTHOR]