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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]

[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]

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]

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]

• 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]

The amino- and phosphorus-codoped (N,P-codoped) porous carbons derived from oil-tea shells were facilely fabricated through a combination of phosphoric acid (H 3 PO 4 ) activation and amino (polyethylenimine, PEI) modification method. The as-synthesized carbon adsorbents were systematically characterized and evaluated for Cr(VI) removal in aqueous solutions. The relationship between adsorbent properties and adsorption behaviors was illustrated. Moreover, the influences of contact time, initial Cr(VI) concentration, pH, coexisting anions and temperature were also investigated. The adsorption behavior of Cr(VI) could be perfectly described by the pseudo-second-order kinetic model and Sips adsorption model. The maximum adsorption capacity of Cr(VI) on the carbon adsorbents synthesized in this work was 355.0 mg/g, and this excellent Cr(VI) capacity could be sustained with other coexisting anions. In addition to high surface area and suitable pore size distribution, the high Cr(VI) removal capacity is induced by rich heteroatoms incorporation and the Cr(VI) removal mechanism was clearly illustrated. Furthermore, the continuous column breakthrough experiment on obtained N,P-codoped carbon was conducted and well fitted by the Thomas model. This work revealed that PEI modification and P-containing groups could significantly enhance Cr(VI) adsorption capacity and make these N,P-codoped biomass-derived carbons potent adsorbents in practical water treatment applications. [ABSTRACT FROM AUTHOR]

Highlights: [•] Antibacterial activity and mechanism of ε-PL against E. coli O157:H7 was investigated. [•] Critical inhibitory factors toward the growth of E. coli O157:H7 by ε-PL was analyzed. [•] Cell membrane integrity and cell morphology of E. coli O157:H7 was affected by ε-PL. [•] A positive correlation between reactive oxygen species levels and ε-PL concentration in E. coli O157:H7 cells. [•] ε-PL induced the expression of different genes related to oxidative/redox stress, SOS response, virulence. [ABSTRACT FROM AUTHOR]

Phytate, an anti-nutritional factor in Cinnamomum camphora seed kernel protein isolate (CPI), chelated with minerals and proteins to form complexes that reduced their bioavailability. The study aimed to evaluate the effects of phytase treatment on the structural and functional properties and in vitro digestibility of CPI. The results showed that the degree of phytate degradation was improved with the increase in phytase treatment time. Most of the original secondary structures were retained in the treated CPI samples. The removal of phytate increased the Zeta potential of CPI, and the protein isoelectric point was increased. Low phytate CPI samples showed higher thermal stability and higher Ca2+ content. In terms of functional properties, foaming capacity was positively correlated with phytate content, whereas foam stability, emulsifying activity index and emulsion stability index were negatively correlated with phytate content. The reduction of phytate content had a positive effect on in vitro gastrointestinal digestion, and the bioavailability of CPI was significantly improved. These results have demonstrated that phytase treatment retained most of the original structure, and improved functional properties and digestibility of the protein isolate from Cinnamomum camphora seed kernel. • The decrease in phytate content changed the ζ-potential of CPI samples. • Most of the secondary structure of the protein was retained after phytase treatment. • Phytase treatment improved functional properties of CPI samples. • The decrease in phytate content improved in vitro digestibility and the availability of protein. [ABSTRACT FROM AUTHOR]

In this study, protein isolate (PI) and protein-phenolic complex (PPC) were prepared from Cinnamomum camphora seed kernel (CCSK). The effects of naturally present phenolic compounds on the structural characteristics, functional properties and antioxidant activities of CCSK protein before and after hydrolysis by Alcalase were evaluated. The formation of PPC was confirmed by the ultraviolet–visible and intrinsic fluorescence spectra. The resultant PPC hydrolysates (PPHs) had higher degree of hydrolysis values than PI hydrolysates (PHs). Fourier transform infrared spectroscopy analysis showed that PHs and PPHs had more disordered structure, with the increase of random coil content. PI and PPC had similar solubility curves in the pH range of 2.0–9.0. However, hydrolysis led to a decrease in the solubility of PHs and PPHs at pH 2.0 and 3.0, and the solubility of PPHs was higher than that of PHs at pH 6.0 and 7.0. In addition, PPC exhibited better emulsifying properties and stronger antioxidant activities than those of PI before and after hydrolysis. These results indicated that PPC and PPHs obtained from CCSK may have great application potential in food industry as functional ingredients. • Protein products PI and PPC were prepared from Cinnamomum camphora seed kernel. • Protein hydrolysates PHs and PPHs were obtained by hydrolysis with Alcalase. • PPHs had higher degree of hydrolysis values than PHs. • Hydrolysis increased the random coil contents of PHs and PPHs. • PPHs showed better emulsifying properties and antioxidant activities than PHs. [ABSTRACT FROM AUTHOR]