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The problem of drug resistance of food borne pathogens is becoming more and more serious. Although traditional antimicrobial agents have good therapeutic effects on a variety of food borne pathogens, more effective antimicrobial agents are still needed to combat the development of drug-resistant food borne pathogens. Plant-based natural essential oils (EOs) are widely used because of their remarkable antimicrobial activity. A potential strategy to address food borne pathogens drug resistance is to use a combination of EOs and antimicrobial agents. Because EOs have multi-target inhibitory effects on microorganisms, combining them with drugs can enhance the activity of the drugs and avoid the emergence of food borne pathogens drug resistance. This paper introduces the main factors affecting the antibacterial activity of EOs and describes methods for evaluating their synergistic antibacterial effects. The possible mechanisms of action of EOs and the synergistic inhibitory effects on pathogens of EOs in combination with antimicrobial agents is described. In summary, the combined use of EOs and existing antimicrobial agents is a promising potential new antibacterial therapy. [ABSTRACT FROM AUTHOR]

In this paper, the influence of the number of ground motions on fragility analysis of 5 MW wind turbines under the excitation of aerodynamic and seismic loads is investigated to acquire the sufficient number of records for reasonable fragility estimation. Two scenarios, parked and normal operation, were simulated with the number of actual recorded ground motions ranging from 2 to 48. The fragility function parameters are estimated by utilizing the method of multiple stripe analysis (MSA), and the relationship between the number of ground motions and estimated parameters for each scenario is discussed. In addition, the influence of the number of ground motions on the range of estimated parameters with a 95% confidence interval is also discussed. The simulation results show that there are significant differences between the two scenarios in terms of fragility analysis for 5 MW wind turbines with the interaction of wind and seismic loads, and the lesser number of earthquakes is needed for a normal operation scenario compared to the parked scenario when obtaining the same accuracy fragility estimation. Furthermore, the appropriate number of ground motions to accurately estimate the fragility parameters of 5 MW wind turbines for the two scenarios is presented herein, which is almost unaffected by different wind spectra. [ABSTRACT FROM AUTHOR]

A novel laccase mimic enzyme Cu–Mn with excellent photothermal properties was firstly prepared via a combination of hydrothermal and in situ synthesis. Cu–Mn nanozymes could catalyze the typical laccase substrate 2,4-dichlorophenol (2,4-DP) to generate the red quinone imine. Further, loading the MnO 2 nanosheets with photothermal properties, Cu–Mn nanozymes possessed not only excellent laccase catalytic activity, but also high photothermal conversion efficiency. The presence of glutathione S-transferase (GST) recovered the glutathione (GSH)-induced weakness of the laccase activity and photothermal properties of Cu–Mn. Hence, a GST enzyme-regulated dual-mode sensing strategy was established based on Cu–Mn nanozymes. The detection limits of GST monitoring based on colorimetric and photothermal methods were 0.092 and 0.087 U/L with response times of 20 min and 8 min, respectively. Furthermore, the proposed method enabled the measuring of GST levels in human serum and was successfully employed in the primary evaluation of hepatitis patients. Another attraction, the impressive photothermal behavior also endowed the Cu–Mn nanozymes with promising antimicrobial properties, which exhibited significant antimicrobial effects against Escherichia coli (E.coli) and Staphylococcus aureus (S.aureus). Unsurprisingly, multifunctional Cu–Mn nanozymes certainly explore new paths in biochemical analysis and antimicrobial applications. [Display omitted] [ABSTRACT FROM AUTHOR]

Knowledge of protein properties is vital for quality assessment in meat systems. This study applied Raman spectroscopy to investigate the relationship between protein oxidation/denaturation and conformational changes in beef during repeated freeze–thaw (RFT). A lower α‐helix and higher β‐sheet content was observed after RFT. The I850 cm−1/I830 cm−1 intensity ratio of tyrosine indicates that tyrosine residues were exposed to the polar environment during RFT. Further, RFT led to increased carbonyl content and surface hydrophobicity, with decreased total sulphydryl content, Ca2+‐ATPase activity and enthalpy of myosin (ΔH1). Subsequently, correlation analysis showed that carbonyl content, Ca2+‐ATPase activity and ΔH1 in beef protein have good correlations with secondary protein structure data, especially ΔH1, which has a strong negative correlation (r = −0.906) with the β‐sheet/α‐helix ratio. Therefore, protein secondary conformation information during RFT has the potential to be used as a parameter for studying the thermal properties of myosin. [ABSTRACT FROM AUTHOR]

[Display omitted] • A strategy for storing electrolytes at the cathode is first proposed. • The prepared PAZ electrode possesses extremely high conductivity. • The assembled battery has an ultrahigh operating voltage window of 2.4 V. • The energy storage mechanism of Zn2+ and polyanion doping and dedoping is proposed. • The strategy enables the operation of batteries with low electrolyte content. To realize green and sustainable energy storage systems, it is urgent to propose emerging strategies to construct and understand the relationship between electrode materials and electrolytes. Based on the strategy of storing the electrolyte in an organic cathode, we prepare a Zn2+-doped polyaniline (PAZ) nano-organic cathode with a re-doping method, which possesses high crystallinity in the (0 1 0) plane and high conductivity compared with conventional H+-doped polyaniline (PA). The resultant Zn//PAZ battery exhibits outstanding electrochemical performance for 3000 cycles at an ultra-high voltage of 2.4 V, attributed to the enhancement of electrolyte concentration and reduction of free water stemming from the dedoping of PAZ. A hybrid charge storage mechanism including Zn2+ and multi-anions insertion/extraction is also demonstrated for the Zn//PAZ batteries during the charge/discharge process. To further expand the practical applications of the strategy, we manufacture an electrolyte-free Zn//PAZ battery, which achieves acceptable performance for 400 cycles. This research provides insight into the relationship between the electrolyte and re-doped polyaniline organic cathode and opens a new avenue for emerging Zinc batteries. [ABSTRACT FROM AUTHOR]

Consumers' pursuit to a healthy lifestyle has promoted people to develop new technologies that can prolong the shelf life of food without the use of preservatives. Compared with other types of preservation, edible microcapsules containing essential oils (EOs) are becoming more and more popular especially the starch microcapsules containing essential oil (EOs-starch microcapsules) because of their environmentally friendly, healthier characteristics and the ability to carry active ingredients. In addition, the EOs-starch microcapsules can also reduce the flavor influence and prolong the action time of essential oil on food through its slow release effect, which can promote the use of EOs in food. Understanding the different collocation of edible starch microcapsules and EOs and the related antibacterial mechanism will be more effective and targeted to promote the application of EOs in the real food system. The review focus on the contribution of EOs-starch microcapsules to prolong the shelf life of food products, (1) binding characteristics of EOs-starch microcapsules were analyzed, (2) systematically summarizing the main materials and methods for preparing the EOs-microcapsules, (3) specifically addressing the action mechanisms of EOs-starch microcapsules on microorganism, (4) discussing the applications of EOs-starch microcapsules in specific food. [ABSTRACT FROM AUTHOR]

In order to reduce the costs and improve the overall performance of building systems, the static optimized design with variable rigidity of piled raft foundations has been widely used in recent years. Variable rigidity design of piled raft foundations that support midrise buildings in high-risk seismic zones can alter the dynamic characteristics of the soil-pile-structure system during an earthquake due to soil-pile-structure interaction. To investigate these aspects, a nuclear power plant sitting on multilayered soil is simulated numerically. The paper describes a numerical modeling technique for the simulation of complex seismic soil-pile-structure interaction phenomena. It was observed that the total shear force on top of the piles and the rocking of the raft are reduced after optimization, whereas the displacement of the superstructure is nearly unaffected. The findings of this study can help engineers select a correct pile arrangement when considering the seismic performance of a building sitting on soft soil. [ABSTRACT FROM AUTHOR]

Bayberries are important sources of phytochemicals. In this paper, the active substances of bayberry extract (BE) were investigated, and based on this, the inhibitory effects of BE on the six tested food-borne pathogens were futher evaluated. Finally, the main antibacterial components in the extracts were identified by UV-Vis absorption spectroscopy, UPLC-UV spectrum and UPLC-ESI-MS. The results showed that the content of total phenolic was the greatest, and BE has a good inhibitory effect on the growth curve of six foodborne pathogens, and average inhibition zone diameter (IZD) reached 19.5 mm. Furthermore, the four main antimicrobial components, cyanidin 3-O-glucoside, flavonoid deoxy hexacoside, quercetin 3-O-glucoside, and quercetin deoxidized hexacoside, were identified from the BE. Practical applications: Bayberries are important sources of phytochemicals such as phenolic acids, anthocyanins, and flavonol glycosides. Recent findings from our laboratory revealed the BE had a significant bacteriostatic effect. Therefore, this paper investigated the antibacterial activity of BE to 6 common foodborne pathogens, and on this basis further confirmed the effective active components of BE. This study provides an important reference for BE application in food, pharmaceutical and chemical fields. [ABSTRACT FROM AUTHOR]

In recent years, with the continuous improvement of people's living standard, the importance of healthy lifestyles is becoming more and more recognized. Therefore, food safety has attracted much attention. This has prompted people to study new technologies that can guarantee food safety without the use of preservatives. Compared with other types of food preservatives, essential oils (EOs) are gotten more attention, because they meet the current development trend of food additives about "green", "safety" and "health". Therefore, this paper focuses on the research of effective contribution of EOs to inhibit the growth of foodborne pathogens, systematically summarized the commonly used EOs and their main extraction methods and chemical components and, the antibacterial mechanism of EOs on food borne pathogens, systematically analysis the specific application case of EOs in food discussed. Hoping to provide some reference and help to the relevant researchers. [ABSTRACT FROM AUTHOR]

For achieving more functionalities of perovskite manganese oxides film, an epitaxial La 0.8 Sr 0.2 MnO 3 (LSMO) film was deposited on a flexible substrate (mica) by pulsed laser deposition. The film shows a paramagnetic-ferromagnetic (PM-FM) phase transition at 134 K together with metal-insulator transition (MIT) at 149 K. The measurement of hysteresis loop indicates that the easy-magnetization axis lied in film plane. The transport behavior can be fitted well with the small polaron model, giving out the activation energy E hop = 176.9 meV. Different from the common anisotropic magnetoresistance (AMR) in manganite film, an isotropic magnetoresistance (IMR) effect was observed in LSMO film and the relatively small thickness of LSMO film (∼ 50 nm) is a major reason for it. After the cyclic flexural bending for 1.0 × 104 times, we found the magnetic properties of LSMO film were improved. Micromagnetic detection shows that the activation energy for polaron hopping (E a = 144.7 meV) remarkably decreases by the cyclic flexural bending process. We suggested that the inhomogeneous/incompact part located at the zone of neighbouring domains become uniform and tight after circulating bending, which facilitates the rotation of domains and the polarons hopping so that the magnetic and electronic performance are enhanced. • A flexible pervoskite manganite film has been fabricated by PLD. • The film shows an exchanged polaron interactions in transport behavior. • An isotropic magnetoresistance effect was observed in film. • The magnetization and electronic transport property have been promoted after the cycling bending. [ABSTRACT FROM AUTHOR]

Compared with other types of packaging, edible coatings are becoming more and more popular because of their more environmentally friendly properties and active ingredients carrying ability. The edible coating can reduce the influence of essential oils (EOs) on the flavor of the product and also can prolong the action time of EOs through the slow-release effect, which effectively promote the application of EOs in food. Understanding the different combinations of edible coatings and EOs as well as their antimicrobial effects on different microorganisms will be more powerful and targeted to promote the application of EOs in real food systems. The review focus on the contribution of the combination of EOs and edible coatings (EO-edible coatings) to prolong the shelf life of food products, (1) specifically addressing the main materials used in the preparation of EO-edible coatings and the application of EO-edible coatings in the product, (2) systematically summarizing the main production method of EO-edible coatings, (3) discussing the antiseptic activity of EO-edible coatings on different microorganisms in food. [ABSTRACT FROM AUTHOR]

• The electronic phase separation has been observed in La 0.8 Sr 0.2 MnO 3. • The state of magnetic skyrmion exists in the temperature region of 290 K–306 K. • A large DM interaction exists in the interface of LaMnO 3 /SrMnO 3. Magnetic skyrmions, being one of the most promising candidates for the next generation memory-type application due to their nanometer-size and efficient current-driven dynamics, are mainly found and studied in alloy helimagnets in which the spin-orbit coupling induced by Dzyaloshinskii-Moriya interaction (DMI) enables noncollinear spin alignment and skyrmion formation. In this paper, we report a possible finding of skyrmions crystal near room-temperature in centrosymmetric structures perovskite manganite La 0.8 Sr 0.2 MnO 3 (LSMO). Based on the measurements of isothermal magnetization around the Curie temperature (∼298 K), an unusual magnetic behavior of a discontinuous magnetization was observed and existed only at moderate magnetic field region together with a narrow temperature range from 306 to 290 K. Apart from this range, all curves return to conventional magnetic behavior of continuous change with external magnetic field. This characteristic has been frequently observed in some reported helimagnets (such as FeGe, MnSi), implying the possible existence of skyrmions crystal in LSMO. To further unveil the physical origin and underlying mechanisms, we performed the first-principles calculation for LSMO compound and a large DMI (Δ E DMI = 13.46 meV, d 1 = 1.68 meV) was found to exists at the interface of LaMnO 3 / SrMnO 3 layers. This result not only supports our experimental findings in the present composition but also is consistent with the formation mechanism of magnetic skyrmions. [ABSTRACT FROM AUTHOR]

[Display omitted] • A novel metal–organic coordination polymer with dual-redox centra was synthesized. • Assembled device shows electrochromic and energy-storage performance simultaneously. • Good cycling durability was revealed due to the synergistic effect of Fe2+ and TPA. Indicative electrochromic supercapacitors have garnered great attention in intelligent power supplies and smart windows, due to their ability to indicate the energy states through optical color changes. Herein, a networked metal–organic coordination polymer bearing dual-redox centra (CONASH) was successfully prepared by coordination interaction of Fe salts with triphenylamine(TPA)-functionalized phenanthroline ligands through the liquid–liquid interface self-assembly strategy. The resultant uniform CONASH film exhibits improved electrochromic and energy-storage performance, attributed to the synergistic effects between the dual-redox centra of Fe ion and TPA moiety. Furthermore, a sandwich-structured electrochromic energy-storage device was fabricated by combining CONASH cathodic film, gel electrolyte, and V 2 O 5 anodic material. The resultant device illustrates a proper optical contrast of 54%, a fast response speed of 5.5 s/4.8 s, a capacitance of 8.12 mF/cm2, excellent rate performance, and good cycling durability (73% retention of capacitance and 95% retention of optical contrast after 6000 charging/discharging cycles). The design principles proposed in this study not only provide new insights for the preparation of high-performance electrochromic supercapacitors materials but also demonstrate the potential applications of CONASH for energy recovery and reuse. [ABSTRACT FROM AUTHOR]

[Display omitted] • A dual-ligand laccase mimic enzyme (Cu-BH) with excellent fluorescence properties is successfully constructed. • The substrate for laccase mimic enzymes is extended from traditional phenolic to amines inspired by natural laccase. • Cu-BH exhibits both favorable catalytic activity stability and fluorescence signal stability. • A multi-modal sensing strategy based on Cu-BH/OPD with boosted catalytic activity and fluorescence signal amplification is adopted for kanamycin analysis. • The visualization of kanamycin analysis is achieved by RGB reading from a smartphone. A copper-based dual-ligand biomimetic enzyme (Cu-BH) inspired by natural laccase was constructed, which had promising laccase-like activity and excellent fluorescence properties. More remarkably, Cu-BH can oxidize not only traditional phenolic substrates, but also catecholamines and amine substrates. As expected, OPD could be catalyzed by Cu-BH to produce the yellow fluorescent product DAP with absorbance and emission peaks at 426 nm and 566 nm, respectively. The generated DAP could quench the Cu-BH fluorescence at 440 nm by fluorescence internal filtration effect (IFE), thus constructing a ratiometric fluorescence signal(F 566 /F 440). Kanamycin further promoted the catalytic activity of Cu-BH by accelerating electron transfer, resulting in a gradual increase in absorbance at 426 nm and fluorescence signal amplification at 566 nm. Based on this, a sensitive dual-mode sensing strategy was established to analyze kanamycin with the LOD of 0.033 and 0.26 nM, which was successfully applied to the monitoring of kanamycin in tap water, milk and honey. The visualization analysis was also achieved by RGB reading from a smartphone. In conclusion, this novel biomimetic enzyme (Cu-BH) had provided a new application path in bioanalysis and environmental monitoring. [ABSTRACT FROM AUTHOR]

[Display omitted] • An electrochromic capacitive window (ECW) was assembled rationally. • ECW exhibits good two-band optical modulation in both Vis and NIR regions. • The indoor brightness and temperature can be regulated readily by ECW. • Power supply to the electronics by ECW, realizing energy recovery and reuse. Electrochromic capacitive windows (ECW) combining energy storage and electrochromism have attracted considerable interest because of their unique energy-saving and energy-recovery features. Therefore, it is highly desirable to explore an electrode material with excellent electrochromic and energy storage properties simultaneously. Herein, we synthesize an electroactive polyamide containing pentaaniline segments (EPA) in the main chain via oxidative coupling polymerization, which showcases electrochemical optical modulation and high capacitance synchronously. Attributed to non-acidic electrolyte and rational matching with V 2 O 5 ion-storage material, the as-fabricated ECW exhibits good dual-band optical modulation performance with high optical contrast of 56.57% at 650 nm (Visible region) and 53.29% at 1250 nm (NIR region), fast optical switching response (<5 s), as well as effective regulation of indoor temperature. The resultant ECW also possesses practical energy storage properties, along with a wide voltage window of 2 V, a large capacitance of 47.26 mF/cm2, and outstanding electrochemical cycling durability. In its coloring state, the energy stored in ECW could be utilized to drive small-scale electronic equipment, indicating its energy recovery and reuse feature. In conclusion, the ECW in this work functions as a color-switching smart window and a rechargeable supercapacitor, which exhibits great promise for development in green buildings. [ABSTRACT FROM AUTHOR]

BACKGROUND Aroma scalping is a very common problem and can affect the sensory quality of packaged food. To study the aroma scalping characteristics of polyethylene terephthalate laminated steel (PET‐LS), the sorption kinetics of six common aroma compounds (2‐pentanone, 2‐heptanone, hexanal, citral, butyl acetate, isopentyl acetate) in foods were assessed for drawn–redrawn cans made with PET‐LS. RESULTS: Storage temperature and initial concentration were proved as important factors to affect compound sorption and diffusion for flavors. The correlation between logarithm of equilibrium absorption ln M∞ and reciprocal of absolute temperature 1/T showed good linear relationship (R2 = 0.9380–0.9998) at 4 °C, 20 °C and 50 °C, and the M∞ obtained by the experiment was very close to the predicted value at 37 °C. At low initial concentration (below 500 µL L−1), the absorption capacity and initial concentration showed a slow linear growth trend, whereas there was a rapid change at high initial concentration. The values of diffusion coefficient D were on the order of 10−11–10−12 m2 day−1, which were lower than reported for other polymer materials (linear low‐density polyethylene, polybutylene succinate, polylactic acid). CONCLUSION: The equilibrium absorption amount of each flavor component was dependent on the temperature under the same concentration (500 µL L−1). The Fickian diffusion model was used for fitting the experimental kinetics values satisfactorily (R2 = 0.9158–0.9885). © 2019 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Abstract Electronic phase separation (EPS) plays a key role in elucidating the effects of complexity on emergent behavior for correlated electronic materials. In this work, we thoroughly studied a robust EPS existed in perovskite manganite La 0.825 Sr 0.175 MnO 3. Results show that a typical paramagnetic-ferromagnetic (PM-FM) phase transition and a metallic-insulating phase transition occur at 285.4 and 295 K, respectively. Electron paramagnetic resonance (EPR) spectroscopy confirms that there are a double peaks rather than a single peak structures in the temperature region of 290 K ≤ T ≤ 315 K, indicating that an obvious EPS state generates in this compound. Based on the variation of EPR intensities, we found that the FM composition continues to increase with the decrease of temperature in the whole EPS region. Moreover, it causes a percolative-like metallic-insulting transition when the percolative threshold approach ∼22.63 % which is nearly equivalent to 25.34 % obtained by calculating the ratio of spontaneous magnetization against theoretical saturated magnetization. Detailed phase diagram shows that the EPS state not only occupies most of PM region but also a state of multiphase coexistence is also found. [ABSTRACT FROM AUTHOR]

Abstract: Oil oxidation is considered to involve the formation of free radicals. In this study, several major fatty acids in peanut oil have been investigated, and it showed that free radicals were mainly generated from the unsaturated fatty acids oleic acid and linoleic acid. Through a fitting analysis of the types of free radicals, they were identified as alkyl peroxy radicals (DMPO-•OOL), alkoxyl radicals (DMPO-•OL), alkyl radicals (DMPO-•L), and unknown radicals (DMPO-•X). In a comparison of two different heating temperatures, at 90 °C the electron spin resonance (ESR) spectrum was dominated by alkoxyl radicals (DMPO-•OL) and an unknown radical (hyperfine splitting constants of α N = 14.73 G and α H = 2.12 G, as befits a comprehensive carbon-centered radical). At 120 °C, the ESR spectrum was dominated by alkyl radicals (DMPO-•L). This study has indicated that ESR provides a powerful method for evaluating free radical generation in the oxidation of peanut oil. Highlights • Electron spin resonance (ESR) provided a powerful method to evaluate the free radicals in oxidation process of peanut oil. • Changes of free radicals from unsaturated fatty acids oleic acid and linoleic acid were studied. • Electron spin resonance (ESR) has potential to evaluate the oxidative stability of peanut oil. [ABSTRACT FROM AUTHOR]

Highlights • Core-shell nanomaterials are synthesized in this study. • It owned sensitive, fast, convenient, nondestructive and with good SERS effect. • It was excellent in rapid detection of pigments in food. Abstract With the widespread application of synthetic pigments in the food industry, food safety incidents caused by illegal addition of pigments have become more frequent. In this study, we synthesized core–shell nanomaterials for use in sensitive, fast, convenient, nondestructive detection and having good surface-enhanced Raman scattering (SERS) effect. The optimal synthetic conditions were selected to study semi-quantitative detection. Calculations for acid orange II and brilliant blue were done using density functional theory, and the characteristic peaks and vibration conditions for each pigment were identified. Acid orange II and brilliant blue in the food samples yellow croaker, braised pork, red pepper, green dumpling, and red wine were detected by SERS screening. Results were compared with those obtained by standard high-performance liquid chromatography method in order to verify the SERS method. The core–shell nanoparticles showed good performance in the rapid detection of pigments in food. [ABSTRACT FROM AUTHOR]

• Physical traits of frozen/thawed (F/T) beef were first predicted using Raman. • Raman is capable of predicting the thawing loss of F/T beef by CARS-PLS. • Raman based UVE-PLS is capable of predicting colour and water content of F/T beef. • T 21 water is contribute to the exudate loss during freeze–thaw. Freeze-thaw accelerated the colour deterioration of beef with the increase of colour b* and the decrease of colour a* values (P < 0.05). The maximum exudate loss reached 22 % after the seventh freeze–thaw. A strong correlation between the transversal relaxation time T 21 and thawing loss may mean that T 21 water contributed to the exudate loss during freeze–thaw. Afterwards, competitive adaptive reweighted sampling-partial least square (CARS-PLS) has the best prediction in thawing loss of frozen/thawed beef with correlation coefficients of prediction (R p) of 0.971, and root mean square error of prediction (RMSEP) of 1.436. Besides, Uninformative variable elimination-partial least squares (UVE-PLS) showed good prediction effects on colour values (R p = 0.932 – 0.994) and water content (R p = 0.928, RMSEP = 0.582) of frozen/thawed beef. Therefore, this work demonstrated that Raman spectroscopy coupled with multivariate calibration has a good ability for non-destructive prediction in colour and water-related properties of frozen/thawed beef. [ABSTRACT FROM AUTHOR]

In this study, we investigated the structural, magnetic phase transition, and magnetocaloric properties of bilayer perovskite manganite La 1.38 Sr 1.62 Mn 2 O 7 based on X-ray diffraction, electron paramagnetic resonance, and temperature-/magnetic field-dependent magnetization measurements. The structural characterization results showed the prepared sample had a tetragonal structure with the space group I 4/ mmm . The Curie temperature was determined as 114 K in the magnetization studies and a second-order paramagnetic-ferromagnetic transition was confirmed by the Arrott plot, which showed that the slopes were positive for all the curves. According to the variation in the electron paramagnetic resonance spectrum, we detected obvious electronic phase separation across a broad temperature range from 220 to 80 K in this magnetic material, thereby indicating that the paramagnetic and ferromagnetic phases coexist above as well as below the Curie temperature. Based on a plot of the isothermal magnetization versus the magnetic applied field, we deduced the maximum magnetic entropy change, which only reached 1.89 J/kg.K under an applied magnetic field of 7.0 T. These theoretical investigations indicated that in addition to the magnetoelastic couplings and electron interaction, electronic phase separation and anisotropic exchange interactions also affect the magnetic entropy changes in this bilayer manganite. [ABSTRACT FROM AUTHOR]

In this study, electron spin resonance (ESR) and Raman spectroscopy were applied to characterize lipid oxidation of beef during repeated freeze–thaw (RFT). Besides the conventional indexes including peroxide values (PV), thiobarbituric acid-reactive substances (TBARS) and acid values (AV) were evaluated, the radical and molecular structure changes were also measured by ESR and Raman spectroscopy. The results showed that PV, TBARS and AV were increased (P < 0.05) after RFT. This suggested that lipid oxidation was occurred during RFT. With the increase of radical signal intensity, lower oxidation stability was presented by ESR. Raman intensity of ν (C C) stretching region (1655 cm −1 ) was decreased during RFT. Furthermore, lower Raman intensity ratio of I 1655 /I 1442 , I 1655 /I 1745 that determine total unsaturation was also observed. Significant correlations (p < 0.01) were obtained among conventional methods, ESR and Raman spectroscopy. Our result has proved that ESR and Raman spectroscopy showed great potential in characterizing lipid oxidation process of beef during RFT. [ABSTRACT FROM AUTHOR]

Fermented soy sauce was identified by determining underivatized amino acids through the proposed capillary electrophoresis-ultraviolet method coupled with sweeping technology for the first time, based on the coordination interaction between amino acids and Cu2+. The essential amino acids pattern was used to the evaluate quality of soy sauce of different grades, the results showed that the quality of special grade soy sauce was higher than that of others. The sample S13 had the highest quality according to the analysis of the 12 kinds of soy sauce by principal component analysis. According to the method of Taste Activity Value, glutamic acids, lysine, alanine, and aspartic acid were considered to be the main taste amino acids in soy sauce. [ABSTRACT FROM AUTHOR]

Herein, a polyacrylic acid sol-gel method was presented to synthesize rare earth doped calcium phosphate nanocrystals (RE-CaP) as cell bioimaging agent. The effects of calcination temperature, calcination time and PAA concentration on phase composition, morphology, size and luminescence were discussed. In addition, the hemolysis, cytotoxicity, cell uptake and cell imaging of resulting RE-CaP nanocrystals were investigated. Results show that the increases in calcination temperature and time promote the transformation of product from impure crystalline phase (CaCO 3 , CaO) to pure CaP phase. The rise of calcination temperature results in significant enhancement of luminescence intensity. PAA concentration does not influence the crystalline phase composition and its increase leads to a little increase in luminescence intensity. In addition, the co-doping of Gd 3+ improves the luminescence intensity of Eu 3+ emissions. This method achieves the doping of Eu 3+ ions in the crystallographic Ca 2+ I and Ca 2+ II sites of HAP with a preferable occupation at Ca 2+ II site. The resulting RE-CaP nanocrystals (PAA: 0.6 mg/mL, Eu/Gd = 2:1.5, 600 °C, 3 h) show good biocompatibility and can be easily uptaken by cancer cells. The internalized nanocrystals show stable and strong red luminescence under visible wavelengths excitation. In summary, PAA sol-gel method can be used to synthesize biocompatible RE-CaP luminescent nanomaterials for cell bioimaging. [ABSTRACT FROM AUTHOR]

Attributed to their obvious color transition, good electrochemical reversibility, and high theoretical capacitance, polyaniline-based electrochromic supercapacitors have recently garnered significant attention in wearable devices, intelligent power supplies, and smart windows. However, its limited processability as well as poor electrochemical endurability have severely hampered polyaniline's practical application in this regard. Herein, a new electroactive polyimide containing pentaaniline in the main chain has been facilely designed and synthesized using oxidative coupling polymerization followed by thermal imidization. Rational matched with vanadium pentoxide ion-storage counter electrode, a quasi-solid-state electrochromic supercapacitor device (QSES) is manufactured with desirable simultaneous optical change and energy storage performance of high optical contrast of 68%, fast switching speed of 1.29/1.58 s, good open circuit memory (1.28% decay after power off for 3600 s), wide voltage window of 2 V, large capacitance of 41.53 mF/cm2, and outstanding cycling durability (85% capacitance and 96% optical modulation retention after 10000 cycles at 0.2 mA/cm2). This study provides a feasible approach of molecular designing for achieving processable electroactive polymer and shows the promising potential of the resultant electrochromic supercapacitor in smart power supply devices with energy level indication functionality. A new electroactive polyimide containing pentaaniline segment in the main chain was designed via oxidative coupling polymerization and thermal imidization. Coupled with V 2 O 5 ion-storage material, the assembled electrochromic supercapacitor affords a high optical contrast of 68%, fast switching speed of 1.29/1.58 s, good open circuit memory (1.28% decay after power off for 3600 s), a wide voltage window of 2 V, a substantial capacitance of 41.53 mF/cm2, and superior cycling durability (85% capacitance and 96% light modulation retention after 10,000 cycles at 0.2 mA/cm2). [Display omitted] • An electroactive polyimide bearing pentaaniline segment (ESPI) was synthesized. • ESPI's precursor exhibited good solubility and favorable processibility. • An electrochromic supercapacitor was assembled based on ESPI and V 2 O 5 (QSES). • QSES showed energy visualization behavior with superior cycling durability. [ABSTRACT FROM AUTHOR]

In this study, a novel hybrid molecularly imprinted polymer (MIP) with a surface-enhanced Raman spectroscopy (SERS) sensor was proposed for the detection of chloramphenicol in milk. The MIP was prepared by precipitation polymerization, and the template molecule was extracted by ultrasonic wave. The polymer was placed in a sodium citrate reduction reaction to prepare the chloramphenicol-MIP-Au substrate. The optimal detection conditions were carried out in a mixed solution of methanol and water (1:9). The sensor can be used to detect chloramphenicol in milk samples with a detection limit of 0.1 µg/ml. The chloramphenicol-MIP-Au substrate served not only as an enrichment medium but also as an enhancement substrate base for SERS detection. Experimental results showed that the MIP hybrid as a SERS platform owned potential for simplifying the detection step and highly selective detection of chloramphenicol in milk. Copyright © 2016 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

In this work, 2-methylimidazole (MI) was doped into the Bpy-Cu nanozyme as a second ligand to form a novel laccase-mimicking enzyme (MI-Bpy-Cu). By comparison, MI-Bpy-Cu nanozyme was identified to have excellent laccase-mimicking activity, high stability and catalytic kinetic properties. It may be that the incorporation of 2-methylimidazole helped the nanozymes to build a structure closer to natural laccase and accelerate the electron transfer rate, thereby achieving the purpose of enhancing the activity. Furthermore, we observed that MI-Bpy-Cu nanozymes could oxidize the colorless (+)-Catechin to generate a yellow radical product, and a novel colorimetric sensing strategy for (+)-Catechin was successfully developed. The method had excellent selectivity and anti-interference properties, and also had good application in the analysis of (+)-Catechin in dairy products. [Display omitted] • The 2-methylimidazole was first incorporated as a second ligand to enhance the activity of laccase-mimicking enzymes. • The nanozyme was modified close to the natural laccase composition. • The colorimetric method was successfully established for the analysis of (+)-Catechin in dairy products. • The method has high selectivity and interference resistance. [ABSTRACT FROM AUTHOR]

Despite the rapid advancement of electrochromic capacitive energy storage, there are still challenges in simultaneously improving electrochemical kinetics and cycling stability. Here we synthesize a new conjugated polymer bearing twisted EDOT-triphenylamine (TPA) dual-redox centers through facile electropolymerization. Benefiting from the multiple electroactive segments, the resultant polymer electrode reveals remarkable multicolor electrochromism (from yellow to green and blue) and concurrently good capacitive energy storage (high capacitance of 39 mF cm−2). The twisted alignment of the TPA structure facilitates ions diffusion and electrochemical reaction kinetics. Coupled with vanadium pentoxide ion-storage material, an assembled asymmetric electrochromic supercapacitor device (AESD) displays a high optical contrast of 71.37%, a wide voltage window of 2 V, the desirable energy density of 20.2 μWh cm−2, and outstanding cycling durability (87% capacitance after 6000 cycles at 0.2 mA cm−2). This method and knowledge offered by density functional theory (DFT) provide another path toward improving electrochromic and capacitive performance in a synergetic manner. A new conjugated polymer bearing dual-redox centers of EDOT and triphenylamine is prepared through facile electropolymerization. Coupled with V 2 O 5 nanowires ion-storage material, an asymmetric electrochromic supercapacitor device is assembled, affording a high optical contrast of 71.37%, a wide voltage window of 2 V, high energy density of 20.2 μWh cm−2, and outstanding cycling durability (87% capacitance after 6000 cycles). [Display omitted] • A conjugated polymer bearing dual-redox centers of EDOT and TPA is synthesized. • Porous morphology stemmed from twisted TPA enhances the charge storage kinetics. • Rational matching with V 2 O 5 material enlarges the voltage window to 2 V. • The electrochromic and energy storage performance are simultaneously improved. [ABSTRACT FROM AUTHOR]

Spin pumping induced inverse spin Hall effect (SP-ISHE) measurement is a widely used technique for searching of materials with strong charge-to-spin conversion efficiency. However, it is actually still not easy to obtain reliable quantitative ISHE voltage (V ISHE) in most of the current widely used SP-ISHE experiment setups. In order to solve this problem, we proposed a SP-ISHE measurement approach employing an air-substrate micro-strip waveguide device, that has been proved to be better than widely used coplanar waveguide (CPW), from both the viewpoints of convenience for sample wiring and reliability for achieved V ISHE. [ABSTRACT FROM AUTHOR]

An ultrasound-induced albumin gelation method was utilized to prepare nanostructured hydroxyapatite (HAP). After ultrasound irradiation, hybrid colloids of bovine serum albumin (BSA) and amorphous calcium phosphate (ACaP) were formed, where the nanosized ACaP was homogenously distributed in the fibril-like BSA matrix. The freeze-dried BSA/ACaP sponge showed an oriented pore structure and the ACaP nanoparticles were transformed into nanostructured HAP after calcinations at 400–600 °C. With the aid of BSA/ACaP sponge, HAP nanocrystals were aggregated into rod-like nanostructures, which were merged into large rod-like HAP crystals at 700 °C. This study demonstrates that ultrasound-induced albumin gelation method can be successfully used to fabricate nanostructured HAP. [ABSTRACT FROM AUTHOR]

BACKGROUND The aim of this research was to understand the migration of bisphenols from can coatings into foods in the Chinese market. RESULTS The migration of bisphenols was studied in commercial cans from the Chinese market filled with four types of food simulant (FS), which were heated at 121 °C for 30 min and stored at 40 °C for 30 days. Only bisphenol A (BPA) and bisphenol A diglycidyl ether (BADGE) were found in the can coatings, and SimC (10% (v/v) ethanol/water) was the most suitable FS for their release. The levels of these bisphenols in 24 kinds of canned beer from Chinese markets were also investigated. The average concentrations of BPA and BADGE were 2.85 ± 0.79 and 0.38 ± 0.19 µg · L−1 respectively, which were both lower than the EU limits, and their respective daily intakes were estimated at 0.015 and 0.0020 µg · kg−1 body weight · day−1. Besides, increasing storage temperature and time accelerated the release of bisphenols into FSs. CONCLUSION The present results provide some guidance to reduce the migration of bisphenols during the transport and storage of canned foods. © 2014 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

A novel logic gate for protamine and trypsin was developed based on a nanozyme with laccase-like activity. It is found for the first time that the nanomaterial (Bpy-Cu) made from 4,4′-bipyridine (Bpy) and Cu2+ has significant laccase-like activity, which could oxidize the typical laccase substrate (2,4-dichlorophenol) and the oxidation product was coupled with 4-aminoantipyrine to form a red dye product. It is also observed that heparin (Hep) can bond to the surface of Bpy-Cu, and obviously enhanced the laccase-like activity of Bpy-Cu by showing a stronger colorimetric reaction. In addition, because of the strong interaction between heparin and protamine, the addition of protamine to the complex of Bpy-Cu/Hep caused the decrease of surface charges as well as the laccase-like activity. Furthermore, protamine could be hydrolyzed by trypsin, and the inhibited laccase-like activity of Bpy-Cu/Hep complex by protamine could be recovered by trypsin. According to the above results, a novel sensing strategy for protamine and trypsin, and an IMPLICATION logic gate was developed. This work provided a new sensing pathway for biological molecules on the basis of the controlled regulation the laccase-like activity of nanozymes. • Laccase-like activity of Bpy-Cu was first investigated. • Heparin enhanced laccase-like activity of Bpy-Cu was observed. • Protamine and trypsin were detected with satisfactory results. • An "IMPLICATION" logic gate based on Bpy-Cu was constructed successfully. [ABSTRACT FROM AUTHOR]

Highlights: [•] IR, Raman and SERS methods have been studied on azodicarbonamide, biurea, and semicarbazide hydrochloride. [•] The molecular structure and assignment of these three molecules have been studied by DFT calculations. [•] The limit of detection of this method being as low as 10μg/mL (less than the standard regulation). [ABSTRACT FROM AUTHOR]

Abstract: A novel surface-enhanced Raman scattering (SERS) sensor made up of a graphene and silver nanocomposite was developed for detecting prohibited colorants in food. This SERS platform exhibited an excellent enrichment effect between the colorant molecules and the graphene and an ability to enhance the Raman spectra of the silver nanoparticles. Detection of different concentrations of each prohibited colorant was carried out by SERS measurements on this novel substrate. In addition, from the SERS spectra of a mixture of four kinds of prohibited colorants, it was possible to easily distinguish each colorant by its characteristic peaks. A control experiment was also performed to compare the SERS spectra obtained using the graphene/silver nanocomposite substrate with spectra obtained using Ag alone as a substrate. The results showed that the SERS nanocomposite was better for detecting prohibited colorants. The proposed method has advantages in terms of providing a simple and rapid method for the sensitive analysis of prohibited additive colorants in food. [Copyright &y& Elsevier]

Abstract: Ponceau 4R is used as a coloring agent in many different products, such as food, drinks, medicines, cosmetics and tobacco. However, ponceau 4R also shows carcinogenic, teratogenic and mutagenic behavior in high doses. In this work, standard Raman, theoretical Raman and surface-enhanced Raman scattering (SERS) spectra have been used to investigate ponceau 4R. More specifically, density functional theory (DFT) calculations have been used to calculate the optimized Raman spectrum of ponceau 4R at the B3LYP/6-31G(d) level. This has provided a better understanding of the optimized geometry and vibrational frequencies of this dye. In addition, the experimental spectrum of ponceau 4R has been compared with the theoretical spectrum; good agreement was obtained. Finally, it has shown that using SERS the detection limit of the ponceau 4R solution can be as low as 5μg/mL. This has been achieved by SERS measurements of ponceau 4R on a substrate of gold nanoparticles. The SERS peaks at 1030, 1236, 1356 and 1502cm−1 were chosen as index for semi-quantitative analysis, showing that the SERS technique provided a useful ultrasensitive method for the detection of ponceau 4R. [Copyright &y& Elsevier]

Nitrofurans are a group of widely used veterinary antibiotics which have been forbidden in many countries. Surface-enhanced Raman spectroscopy (SERS) coupled with gold nanoparticles was used in this study for the rapid detection and characterization of nitrofuran antibiotics (including furadantin, furaltadone, and their mixture). Density functional theory calculations were conducted with Gaussian 03 at the B3LYP level using the 6-31G(d) basis set to analyze the assignment of vibrations. The SERS measurement of nitrofuran antibiotics has been investigated by active SERS substrate of gold nanoparticles with average size around 50 nm. The SERS qualitative analysis has been studied for furadantin and furaltadone by their characteristic SERS peaks. The peaks at 1,420 and 1,456 cm could be used to discriminate between the two compounds in a mixture. The SERS peaks at 1,008 and 1,162 cm were used as the index of quantitative analysis for furadantin and furaltadone, respectively. Under optimal conditions, the limit of detection could reach the level of 5 ppm. The results showed that the SERS method with gold nanoparticles is capable of identifying and characterizing furaltadone and furadantin, which is valuable to be further applied on the detection of antibiotic residues in food samples. [ABSTRACT FROM AUTHOR]

Methamidophos (MAP) is a highly efficient and broad-spectrum organophosphate pesticide. In this study, a rapid method for detecting MAP in vegetables using surface enhanced Raman scattering (SERS) spectroscopy has been established. Density functional theory calculations were performed with Gaussian 03 at RB3LYP level and with the 6-311G (d) basis set. SERS, normal and theoretical Raman spectroscopy were compared to investigate the mechanism of Raman scattering enhancement. The SERS signal of MAP was improved in alkaline conditions with optimum scattering efficiency at pH of 13.46. Furthermore, MAP detection in vegetables by SERS method had a good linear relationship between 0.01 and 1,000 μg/mL. The concentration of MAP in vegetables was detected and chosen for recovery test with three levels: 4, 8, and 15 μg/mL. The results of three level tests were 86.7-96.6 % and their relative standard deviations were between 1.2 and 2.5 %, which shows the good repeatability of this method. [ABSTRACT FROM AUTHOR]

Abstract: Pefloxacin mesylate, a broad-spectrum antibacterial fluoroquinolone, has been widely used in clinical practice. Therefore, it is very important to detect the concentration of Pefloxacin mesylate. In this research, the near-infrared spectroscopy (NIRS) has been applied to quantitatively analyze on 108 injection samples, which was divided into a calibration set containing 89 samples and a prediction set containing 19 samples randomly. In order to get a satisfying result, partial least square (PLS) regression and principal components regression (PCR) have been utilized to establish quantitative models. Also, the process of establishing the models, parameters of the models, and prediction results were discussed in detail. In the PLS regression, the values of the coefficient of determination (R 2) and root mean square error of cross-validation (RMSECV) of PLS regression are 0.9263 and 0.00119, respectively. For comparison, though applying PCR method to get the values of R 2 and RMSECV we obtained are 0.9685 and 0.00108, respectively. And the values of the standard error of prediction set (SEP) of PLS and PCR models are 0.001480 and 0.001140. The result of the prediction set suggests that these two quantitative analysis models have excellent generalization ability and prediction precision. However, for this PFLX injection samples, the PCR quantitative analysis model achieved more accurate results than the PLS model. The experimental results showed that NIRS together with PCR method provide rapid and accurate quantitative analysis of PFLX injection samples. Moreover, this study supplied technical support for the further analysis of other injection samples in pharmaceuticals. [Copyright &y& Elsevier]

The elegant electroswitchable color/emission properties of electrochromic/electrofluorochromic dual-functional materials motivates the exploration of their new applications. In this work, a new poly (urea-urethane) was synthesized via nucleophilic copolymerization of electroactive oligoaniline derivative, solid-emissive tetraphenylethylene groups, and alkyl isocyanate. The resultant poly (urea-urethane) exhibited good electroactivity and desirable aggregation-induced emission properties. High-performance electrochromic/electrofluorochromic behavior had been disclosed with a high optical contrast ratio of ΔT = 50.4%, a moderate fluorescence on/off ratio of 10.5, and high coloration efficiency of 503 cm2/C at 768 nm. A reflective/emissive dual-mode display device had also been manufactured based on the resultant poly (urea-urethane) and charge-balancing V 2 O 5 , exhibiting a reversible color change and tunable fluorescence conversion upon the electric stimulus. Furthermore, this polymer showed an interesting color/fluorescence response to H 2 O 2 , due to the linkage mechanism between its redox states and optical properties. The spray-coated poly (urea-urethane) test strips were employed in visualized dual-determination of H 2 O 2 with gradual color change from gray to dark green, along with an obvious fluorescence change from light blue to dark, which displays easy operation and rapid detection. This work reports the synthesis of an electrochromic/electrofluorochromic poly (urea-urethane) bearing AIE-active groups and electroactive oligoaniline segments, which shows great potentials in reflective/emissive dual-mode display and colorimetric/fluorometric dual-determination of H 2 O 2. [Display omitted] • A new poly (urea-urethane) (PUU) bearing AIE and oligoaniline groups was synthesized. •PUU displays electrochromic/electrofluorochromic dual-functional performance. •A reflective/emissive dual-mode display device was fabricated based on PUU and V 2 O 5. •Spray-coated PUU test strips were employed in visualized dual-determination of H 2 O 2. [ABSTRACT FROM AUTHOR]

BACKGROUND RESULTS CONCLUSION Mycotoxin contamination of food has been gaining increasing attention. Hidden mycotoxins that interact with biological macromolecules in food could make the detection of mycotoxins less accurate, potentially leading to the underestimation of the total exposure risk. Interactions of the mycotoxins alternariol (AOH) and alternariol monomethyl ether (AME) with high‐molecular glutenin were explored in this study.The recovery rates of AOH and AME (1, 2, and 10 μg kg−1) in three types of grains (rice, corn, and wheat) were relatively low. Molecular dynamics (MD) simulations indicated that AOH and AME bound to glutenin spontaneously. Hydrogen bonds and π‐π stacking were the primary interaction forces at the binding sites. Alternariol with one additional hydroxyl group exhibited stronger binding affinity to glutenin than AME when analyzing average local ionization energy. The average interaction energy between AOH and glutenin was −80.68 KJ mol−1, whereas that of AME was −67.11 KJ mol−1.This study revealed the mechanisms of the interactions between AOH (or AME) and high‐molecular glutenin using MD and molecular docking. This could be useful in the development of effective methods to detect pollution levels. These results could also play an important role in the evaluation of the toxicological properties of bound altertoxins. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Fusarium solani (CICC 2603) is one of the main postharvest spoilage strains of many fruits and vegetables. This research was to investigate the synergistic antifungal mechanism of thymol and salicylic acid (S TSA) on F. solani. Morphological observation showed that the cell structure and morphology changed seriously after S TSA treatment. Determination of F. solani stained cells with propidium iodide (PI) indicated that S TSA damaged the integrity of cell membrane, and the contribution of salicylic acid was greater than that of thymol. Meanwhile, the increase in the absorbance of 260 nm and 280 nm demonstrated that S TSA caused the leakage of cell contents severely, and the contribution of thymol was greater than that of salicylic acid. In addition, the decrease of ergosterol biosynthesis showed that S TSA interfered with membrane function of F. solani. Mitochondrial membrane potential (MMP) and enzymes activities of tricarboxylic acid (TCA) cycle experiments demonstrated that the mitochondrial function was seriously injured in F. solani. These results showed that S TSA inhibited the activity of F. solani more effectively than thymol or salicylic acid alone, by disrupting integrity and function of the cell membrane, causing leakage of the cell contents, meanwhile inhibiting function of the mitochondria, ultimately resulting in cell death. • The combination of thymol and salicylic acid (S TSA) had synergistic inhibition effect on F. solani. • S TSA treatment induced the disruption of cell membrane integrity and permeability. • S TSA treatment severely damage the morphology and function of mitochondria. • Thymol and salicylic acid played different role in synergistic antifungal effect. [ABSTRACT FROM AUTHOR]

The removal of pesticide residues from fruits reduces the risk of pesticide exposure in humans. In this study, carbosulfan and trichlorfon residues removed from apple using ozone-microbubble treatment (OMBT), tap water, hypochlorous acid-water, ozone-water, and microbubble-water. The pesticide removal rates by OMBT ranged between 98% and 100%. In addition, OMBT had little effects on apple surface color. In addition, this work evaluated the interaction between apple matrix and pesticide molecules, including the binding sites and adsorption energy, and proposed a possible adsorption mechanism. OMBT is an effective technique for removing pesticide residues from fruits. The removal effect of pesticides may be related to the matrix components on the surface of fruits. • OMBT was evaluated in pesticide removal. • The surface matrix of apple was studied. • The properties of pesticide molecules were analyzed. • The possible adsorption mechanism was proposed. [ABSTRACT FROM AUTHOR]

Traditional packaging has reached its limits in ensuring food quality and prolonging shelf life. In this study, we developed antifungal sachets containing essential oils (EOs) in microcapsules (ASEOs-CM) and evaluated their application potential in bread preservation. The results showed that the release of EOs from ASEOs-CM at 25 °C followed first-order kinetics. In addition, EOs-containing ASEOs-CM had strong inhibitory effects on microorganisms in vitro and effectively inhibited the growth of molds and yeasts on sliced bread. In the experimental group, the contents of eugenol and citral EOs on bread increased during storage. Breads in three different packages (LDPE, PP and HDPE) had a total shelf life of 13, 13, and 15 d, respectively, while control breads had a shelf life of 5 d. Sachets did not affect the sensory properties of bread. Therefore, the use of ASEOs-CM was an effective, safe, and sustainable preservation method for breads. • The sachets of compound essential oil containing microcapsules were developed. • The sachets has good antifungal activity. • The sachets has no effect on the sensory characteristics of bread. • The sachets can be used to extend the shelf life of baked products. [ABSTRACT FROM AUTHOR]

Hexanal is an essential oil component which has quorum sensing (QS) inhibitor effect on vegetable spoilage bacteria such as Erwinia carotovora (E. carotovora) and Pseudomonas fluorescens (P. fluorescens). However, the QS inhibitory (QSI) effect of hexanal on Autoinducer‐2 (AI‐2), biofilm formation, and enzyme activity is not well understood. Our results showed that the contents of AI‐2 produced by E. carotovora were higher than P. fluorescens, and the 4,5‐Dihydroxy‐2,3‐pentanedione (DPD) concentrations were significantly (p <.05) inhibited by hexanal. Adding DPD exogenously could form more biofilm when inhibited by 1/2 of minimum inhibitory concentration (MIC) of hexanal, which showed that QSI effect of hexanal on biofilm was due to its inhibition on AI‐2. There was no significant increase in enzyme activity, which suggested that enzyme inhibition by hexanal may not due to AI‐2. Understanding the relationship between QSI effect of hexanal on AI‐2, biofilm formation, and enzyme activity can improve to suppress decomposition of vegetables after harvest. Practical applications: Hexanal is an EO component which has shown good QSI effect on biofilm formation and exoenzyme activities of P. fluorescens and E. carotovora. However, the reason for the QSI effect of hexanal was still unclear. In this study, hexanal as a QS inhibitor on these two vegetable spoilage bacteria was studied from the perspective of AI‐2 signal molecule. Understanding the QS inhibition of hexanal on AI‐2 signal molecule of spoilage bacteria and its relationship with biofilm formation and enzyme activity was necessary for the application of more EO components as QS inhibitor to suppress corruption of vegetables after harvest. [ABSTRACT FROM AUTHOR]

• The combination of eugenol and citral (S EC) can inhibit energy metabolism of Penicillium roqueforti. • The S EC can damage the cell membrane of mycelia. • The S EC affect the composition of cell membrane fatty acids. • The S EC can inhibit the expression of succinate dehydrogenase, isocitrate dehydrogenase and fumarate hydratase related genes. Agriculture products spoilage caused by mold not only causes huge economic losses, but also poses a safety hazard to human health. Although essential oils (EOs) are widely used for agriculture products antisepsis, little is known about the synergistic antifungal mechanisms of their major components. In this paper, the synergistic mechanism of eugenol and citral (S EC) on Penicillium roqueforti was studied. The results showed that S EC caused irreversible damage to the cell membrane of P. roqueforti , resulting in significant changes in membrane protein conformation and fatty acid content, among which citral had a greater effect on fatty acid content than eugenol. Through the analysis of mitochondrial morphology and membrane potential, it was found that S EC treatment resulted in serious collapse of mitochondria and significant increase of membrane potential. In this process, the contribution rate of eugenol was higher than that of citral. Further analysis of the tricarboxylic acid cycle (TCA) pathway showed that S EC could inhibit the activity of key enzymes and the production of energy charge in the TCA pathway, resulting in significant down-regulation of gene expression of three key molecules (succinate dehydrogenase, isocitrate dehydrogenase and fumarate hydratase). In conclusion, these results indicated that S EC could kill P. roqueforti through the tricarboxylic acid cycle. [ABSTRACT FROM AUTHOR]

• The combination of eugenol and citral (S EC) has synergistic inhibitory effect on A. niger. • S EC could damage the morphology of A. niger cells significantly. • S EC treatment could significantly induce lipid peroxidation and increase membrane permeability. • The antimicrobial sachets containing S EC could significantly prolong the shelf life of bread. Consumers' preferences for cleaner label products require the food industry to replace synthetic preservatives with natural substitutes. Therefore, the synergistic inhibitory effect of eugenol and citral (S EC) on Aspergillus niger was explored. On this basis, the antimicrobial sachet containing S EC was developed and its application potential in bread preservation was evaluated. The content of reactive oxygen species (ROS) and malondialdehyde (MDA) showed that S EC could significantly induce lipid peroxidation in cell membranes, in which citral played a leading role. The permeation experiments of SEM, TEM, propyl iodide and fluorescein diacetate showed that S EC could destroy the integrity of the cell membrane. Eugenol contributed more than citral. The OD 260 and the relative conductivity of the S EC group increased by 5.2 and 4.1 times, respectively, after 8 h. Finally, the shelf life experiment of bread showed that the antimicrobial sachets containing S EC could significantly prolong the shelf life of bread without producing unpleasant odour. [ABSTRACT FROM AUTHOR]

The synergistic effects of different essential oils can not only reduce their dosage and cost, but also improve their biological activity. The aim of this study was to evaluate the synergistic antifungal effect of eugenol and citral (S EC) on Penicillium roqueforti. Determination of reactive oxygen species (ROS) and malondialdehyde content indicated that S EC could induce membrane lipid peroxidation, and the contribution of citral was greater than that of eugenol. In addition, downregulation of the gene encoding an NADPH oxidase subunit indicated that the ROS burst induced by S EC was mediated by NADPH oxidase. Scanning electron microscope (SEM) and transmission electron microscope (TEM), propidium iodide treatment, DNA gel electrophoresis and cell leakage experiments showed that S EC destroyed the integrity of the cell membrane and internal structures, and degraded the cell contents, and the contribution of eugenol was greater than that of citral. These results showed that S EC inhibited the activity of P. roqueforti more effectively than eugenol or citral alone, by inducing membrane lipid peroxidation and promoting the ability of eugenol to destroy the cell membrane. The combined agents eventually caused leakage of the cell contents, and ultimately cell death. •The combination of eugenol and citral (S EC) had synergistic inhibition effect against P. roqueforti. •S EC treatment could significantly induce lipid peroxidation. •S EC treatment resulted in damaged the morphology of cells. •S EC treatment resulted in loss of plasma membrane integrity. [ABSTRACT FROM AUTHOR]

• Electron spin resonance (ESR) spectroscopy has been evaluated on the oxidative stability of oils. • Induction Periods (IP) have been determined by Boltzmann equation fitting. • ESR method can predict the oxidative stabilities provided by the Rancimatt method. Evaluation on the oxidative stability of oils, based on the tendency of free radicals production, can be operated by using electron spin resonance (ESR) spectroscopy. Induction Periods (IP) can be determined by Boltzmann equation fitting under accelerated conditions (heated). The IPs were compared with IPs of Rancimat method, and high linear correlation was found between these two methods (r = 0.996 and 0.985 separately), suggesting that ESR method can predict the oxidative stabilities provided by the Rancimatt method. This study indicated that ESR provided a sensitive method to evaluate the oxidative stability of edible oils. [ABSTRACT FROM AUTHOR]

To control the spoilage of bread products and reduce the costs associated with preventing their spoilage, the synergistic antifungal effects of natural agents against the main bread spoilage fungi Penicillium roqueforti and Aspergillus niger were studied. After screening 66 groups antifungals using the checkerboard method, only one combination, i.e., that of eugenol and citral (S EC), showed synergistic effects against both the fungi. Their average minimal inhibitory concentrations (MICs) decreased significantly when they were present as a combination, i.e., by 3.40-fold, compared to the case when each agent was used separately. S EC inhibited the spore germination of both the fungi by more than 95% at 2 × MIC. At the same time, their mycelial growth was almost completely inhibited. The morphology of the mycelia was further observed by SEM. Serious wrinkles and deformations were found on the surface of the mycelia at 2 × MIC. Finally, the shelf life tests showed that treatment with S EC significantly prolonged the molding time of bread. These results showed that S EC may serve as a spoilage control measure and reduce the costs associated with preventing bread spoilage. • The combination of citral and eugenol (S EC) had a synergistic effect on both mold. • S EC effectively inhibited spore germination and mycelial growth. • S EC could significantly prolong the shelf life of bread. [ABSTRACT FROM AUTHOR]

The accurate determination of the Curie temperature (T C) is particularly important in describing the magnetic behavior close to the paramagnetic-ferromagnetic (PM-FM) phase transition. In this paper, we studied the magnetic phase transition and accurately predicted the Curie point of perovskite manganite La 0.825 Sr 0.175 MnO 3. We find the compound shows a second-order PM-FM transition and has a large magnetic entropy change (MEC) in vicinity of phase transition region. Based on the scaling law and the correlation between magnetic field and MEC, the precise and magnetic-independent Curie temperature was determined to be 281.7 K, obviously lower than 285.4 K decided from the magnetization versus temperature. The reliability of new Curie temperature can be well confirmed by the modified Arrott plot together with the critical exponents. Our results not only open up a new pathway for precise definition of Curie point but also facilitate the efficient exploitation of spontaneous magnetic bubbles in perovskite manganite. • The accurate Curie temperature of La 0.825 Sr 0.175 MnO 3 was determined by the scaling method. • The PM-FM phase transition of La 0.825 Sr 0.175 MnO 3 was confirmed to be second-order phase transition. • The reliability of Curie temperature was proved by the modified Arrott plot and critical exponents. [ABSTRACT FROM AUTHOR]