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Pseudomonas fragi (P. fragi) is usually detected in low-temperature meat products, and seriously threatens food safety and human health. Therefore, the study investigated the antibacterial mechanism of linalool against P. fragi from membrane damage and metabolic disruption. Results from field-emission transmission electron microscopy (FETEM) and atomic force microscopy (AFM) showed that linalool damage membrane integrity increases surface shrinkage and roughness. According to Fourier transform infrared (FTIR) spectra results, the components in the membrane underwent significant changes, including nucleic acid leakage, carbohydrate production, protein denaturation and modification, and fatty acid content reduction. The data obtained from amino acid metabolomics indicated that linalool caused excessive synthesis and metabolism of specific amino acids, particularly tryptophan metabolism and arginine biosynthesis. The reduced activities of glucose 6-phosphate dehydrogenase (G6PDH), malate dehydrogenase (MDH), and phosphofructokinase (PFK) suggested that linalool impair the respiratory chain and energy metabolism. Meanwhile, genes encoding the above enzymes were differentially expressed, with pfkB overexpression and zwf and mqo downregulation. Furthermore, molecular docking revealed that linalool can interact with the amino acid residues of G6DPH, MDH and PFK through hydrogen bonds. Therefore, it is hypothesized that the mechanism of linalool against P. fragi may involve cell membrane damage (structure and morphology), disturbance of energy metabolism (TCA cycle, EMP and HMP pathway) and amino acid metabolism (cysteine, glutamic acid and citrulline). These findings contribute to the development of linalool as a promising antibacterial agent in response to the food security challenge.

Direct barrier discharge (DBD) plasma is a potential antibacterial strategy for controlling Fusarium oxysporum (F. oxysporum) in the food industry. The aim of this study was to investigate the inhibitory effect and mechanism of action of DBD plasma on F. oxysporum. The result of the antibacterial effect curve shows that DBD plasma has a good inactivation effect on F. oxysporum. The DBD plasma treatment severely disrupted the cell membrane structure and resulted in the leakage of intracellular components. In addition, flow cytometry was used to observe intracellular reactive oxygen species (ROS) levels and mitochondrial membrane potential, and it was found that, after plasma treatment, intracellular ROS accumulation and mitochondrial damage were accompanied by a decrease in antioxidant enzyme activity. The results of free fatty acid metabolism indicate that the saturated fatty acid content increased and unsaturated fatty acid content decreased. Overall, the DBD plasma treatment led to the oxidation of unsaturated fatty acids, which altered the cell membrane fatty acid content, thereby inducing cell membrane damage. Meanwhile, DBD plasma-induced ROS penetrated the cell membrane and accumulated intracellularly, leading to the collapse of the antioxidant system and ultimately causing cell death. This study reveals the bactericidal effect and mechanism of the DBD treatment on F. oxysporum, which provides a possible strategy for the control of F. oxysporum.

The collapsible loess will rapidly soften and lose its bearing capacity when soaked in water. Under a mild condition (20 °C), the biomimetic inorganic agent, diammonium phosphate (DAP), reacts with calcite in the collapsible loess, producing a stronger bonding material, hydroxyapatite (HAP), to modify and stabilize the soil. Uniaxial compression, permeability tests, and morphological analysis using X-ray diffraction and scanning electron microscopy equipped with an energy X-ray dispersive system were used to assess the effectiveness of DAP stabilization on the collapsible loess. The results indicated that HAP improved the inter-particle bonding within the loess, filled the pores within particles, reduced the permeability, and consequently mitigated the collapsibility of the loess. The compressive strength of the DAP-treated loess increased as DAP concentration increased. Following 28 days of curing, the compressive strength of the loess treated with a 3.0 mol/L DAP solution was six times greater than that of the untreated group. DAP’s reinforcement effect on the loess was superior to that of cement. The compressive strength of the DAP-treated loess was about double that of the cement-treated loess and the permeability coefficient was reduced by more than 50% at equivalent solid content. Furthermore, DAP generated 82% fewer carbon emissions compared to Portland cement. Considering eco-friendly and sustainable development, DAP offers a more competitive alternative for modification and stabilization of loess.

In satellite networks, existing congestion resolution methods do not consider the predictability and stability of paths, leading to frequent path switches and high maintenance costs. In this regard, we propose a novel congestion resolution approach, named MOLM, which introduces a continuous neighbor set during path updates. This set includes nodes capable of establishing sustainable connections with the predecessors and successors of congested nodes. Combined with a multi-objective simulated annealing framework, MOLM iteratively derives an optimal selection from this set to replace congested nodes. Additionally, we employ a Fast Reroute mechanism based on backup paths (FRR-BP) to address node failures. The simulation results indicate that the optimal node endows the new path with optimal path stability and path latency.

With the vigorous development of the Internet of Things, 5G technology, and artificial intelligence, flexible wearable sensors have received great attention. As a simple and low-cost power supply in wearable sensors, the triboelectric nanogenerator (TENG) has a wide range of applications in the field of flexible electronics. However, most polymers are thermally poor conductors (less than 0.1 W/(m·K)), resulting in insufficient heat dissipation performance and limiting the development of TENG. In this study, a high-performance non-woven fabric TENG with strong thermal conductivity (0.26 W/m·K) was achieved by introducing ZrB2 into the polyurethane (PU) matrix. The excellent output performance with an open circuit voltage (Voc) of 347.6 V, a short circuit current (Isc) of 3.61 μA, and an accumulated charge of 142.4 nC endows it with good sensitivity. The electrospun PU/ZrB2 composites exhibit excellent sensing performance to detect body movements in situ, such as pressing, clapping, running, and walking. Moreover, the generated power can light up 224 LED bulbs as a demonstration of self-powering ability.

It has been reported that in an oxidative environment, the flavonoid 2R,3R-dihydroquercetin (2R,3R-DHQ) oxidizes into a product that rearranges to form quercetin. As quercetin is a very potent antioxidant, much better than 2R,3R-DHQ, this would be an intriguing form of targeting the antioxidant quercetin. The aim of the present study is to further elaborate on this targeting. We can confirm the previous observation that 2R,3R-DHQ is oxidized by horseradish peroxidase (HRP), with H2O2 as the oxidant. However, HPLC analysis revealed that no quercetin was formed, but instead an unstable oxidation product. The inclusion of glutathione (GSH) during the oxidation process resulted in the formation of a 2R,3R-DHQ-GSH adduct, as was identified using HPLC with IT-TOF/MS detection. GSH adducts appeared on the B-ring of the 2R,3R-DHQ quinone, indicating that during oxidation, the B-ring is oxidized from a catechol to form a quinone group. Ascorbate could reduce the quinone back to 2R,3R-DHQ. No 2S,3R-DHQ was detected after the reduction by ascorbate, indicating that a possible epimerization of 2R,3R-DHQ quinone to 2S,3R-DHQ quinone does not occur. The fact that no epimerization of the oxidized product of 2R,3R-DHQ is observed, and that GSH adducts the oxidized product of 2R,3R-DHQ on the B-ring, led us to conclude that the redox-modulating activity of 2R,3R-DHQ quinone resides in its B-ring. This could be confirmed by chemical calculation. Apparently, the administration of 2R,3R-DHQ in an oxidative environment does not result in ‘biotargeting’ quercetin.

Extracellular vesicles (EVs) play critical roles in intercellular communication by transporting bioactive cargo to recipient cells. EVs have been implicated in a range of physiological and pathological processes, including tumor progression, metastasis, immune modulation, and drug resistance. The objective of this review is to present a thorough overview of recent studies focusing on EVs in hepatocellular carcinoma (HCC), with an emphasis on their potential utility as diagnostic biomarkers as well as therapeutic agents. Initially, we explore the utility of EVs as diagnostic biomarkers for HCC, followed by a discussion of their potential as carriers of therapeutic payloads. Additionally, we delve into the emerging field of therapeutic EVs for modulating tumor immune responses. Through this review, our ultimate aim is to provide a comprehensive understanding of the opportunities and challenges in the clinical translation of EV research in the domain of HCC.

Mango juice (MJ) was co-inoculated with Lactobacillus plantarum + Rhodotorula glutinis or Metschnikowia pulcherrima (LP + RG or LP + MP, respectively) and Lactobacillus casei + Rhodotorula glutinis or Metschnikowia pulcherrima (LC + RG or LC + MP, respectively) to evaluate their effect on the physicochemical characteristics, antioxidant capacity, and aroma compounds of MJ after 72 h of fermentation at 28 °C. Results indicated that among the fermented MJ, that which was fermented with LC + RG yielded the highest content of total acid (15.05 g/L). The pH values of MJ fermented with LC + MP, LC + RG, LP + RG, and LP + MP were 3.36, 3.33, 3.26, and 3.19, respectively, and were lower than that of CK (4.79). The juice fermented with LP + MP culture had the lowest sugar content (73.52 g/L), and those fermented with LP + RG and LP + MP had higher total phenol contents and stronger DPPH radical scavenging activity, ABTS radical scavenging activity, iron-reducing antioxidant capacity, and copper reducing antioxidant capacity than the others. Carotenoids in MJ had varying degrees of degradation after mixed fermentation by using all four combinations. Volatile compounds revealed that the co-fermentation of LP + RG produced increased norisoprenoid aroma compounds. The mixed co-inoculation method is a strategy to contemplate for MJ fermentation, but the modalities of inoculation need further investigation. Success depends on the suitable combination of non-Saccharomyces and lactic acid bacteria and consideration of strain variation.

In this paper, we report the preparation of a gas diffusion layer (GDL) with different gradient pore size structures. The pore structure of microporous layers (MPL) was controlled by the amount of pore-making agent sodium bicarbonate (NaHCO3). We investigated the effects of the two-stage MPL and the different pore size structures in the two-stage MPL on the performance of proton exchange membrane fuel cells (PEMFC). The conductivity and water contact angle tests showed that the GDL had outstanding conductivity and good hydrophobicity. The results of the pore size distribution test indicated that introducing a pore-making agent altered the pore size distribution of the GDL and increased the capillary pressure difference within the GDL. Specifically, there was an increase in pore size within the 7–20 μm and 20–50 μm ranges, which improved the stability of water and gas transmission within the fuel cell. The maximum power density of the GDL03 was increased by 37.1% at 40% humidity, 38.9% at 60% humidity, and 36.5% at 100% humidity when compared to the commercial GDL29BC in a hydrogen-air environment. The design of gradient MPL ensured that the pore size between carbon paper and MPL changed from an initially abrupt state to a smooth transition state, which significantly improved the water and gas management capabilities of PEMFC.

The areca nut is one of the most important cash crops in the tropics and has substantial economic value. However, the research information about the edible quality of different areca nuts is still insufficient. This study compared the composition, texture characteristics and flavor release behaviors of four different areca nuts (AN1, AN2, AN3 and AN4) and two commercially dried areca nuts (CAN1 and CAN2). Results showed that AN1 had higher soluble fiber and lower lignin, which was the basis of its lower hardness. Meanwhile, the total soluble solid (TSS) of AN1 was the highest, which indicated that AN1 had a moister and more succulent mouthfeel. After the drying process, the lignification degree of AN1 was the lowest. Through textural analyses, the hardness of AN1 was relatively low compared to the other dried areca nuts. AN1, CAN1 and CAN2 had higher alkaline pectin content and viscosity, and better flavor retention, which indicated better edible quality. The present study revealed the differences of various areca nuts and provided vital information to further advance the study of areca nuts.

The development of functional edible films is promising for the food industry, and improving the water barrier of edible films has been a research challenge in recent years. In this study, curcumin (Cur) was added to zein (Z) and shellac (S) to prepare an edible composite film with a strong water barrier and antioxidant properties. The addition of curcumin significantly reduced the water vapor permeability (WVP), water solubility (WS), and elongation at break (EB), and it clearly improved the tensile strength (TS), water contact angle (WCA), and optical properties of the composite film. The ZS–Cur films were characterized by SEM, FT-IR, XRD, DSC, and TGA; the results indicated that hydrogen bonds were formed among the curcumin, zein, and shellac, which changed the microstructure and improved the thermal stability of the film. A test of curcumin release behavior showed controlled release of curcumin from the film matrix. ZS–Cur films displayed remarkable pH responsiveness, strong antioxidant properties, and inhibitory effects on E. coli. Therefore, the insoluble active food packaging prepared in this study provides a new strategy for the development of functional edible films and also provides a possibility for the application of edible films to extend the shelf life of fresh food.

Linalool showed a broad-spectrum antibacterial effect, but few studies have elucidated the antibacterial mechanism of linalool on Pseudomonas fragi (P. fragi) to date. The present study aimed to uncover the antimicrobial activity and potential mechanism of linalool against P. fragi by determining key enzyme activities and metabolites combined with a high-throughput method and metabolomic pathway analysis. As a result, linalool had excellent inhibitory activity against P. fragi with MIC of 1.5 mL/L. In addition, the presence of linalool significantly altered the intracellular metabolic profile and a total of 346 differential metabolites were identified, of which 201 were up-regulated and 145 were down-regulated. The highlight pathways included beta-alanine metabolism, pantothenic acid and CoA metabolism, alanine, aspartate and glutamate metabolism, nicotinate and nicotinamide metabolism. Overall, linalool could cause metabolic disorders in cells, and the main metabolic pathways involved energy metabolism, amino acid metabolism and nucleic acid metabolism. In particular, the results of intracellular ATP content and related enzymatic activities (ATPase, SDH, and GOT) also highlighted that energy limitation and amino acid disturbance occurred intracellularly. Together, these findings provided new insights into the mechanism by which linalool inhibited P. fragi and theoretical guidance for its development as a natural preservative.

Pseudomonas fragi is the dominant spoilage bacterium that causes the deterioration of chilled meat. Our previous study showed that linalool has potent antibacterial activity against P. fragi, but its antibacterial mechanism is unclear. To explore the antibacterial mechanism of linalool against P. fragi, this study used RNA-seq technology to perform transcriptome analysis of P. fragi samples with or without linalool treatment (1.5 mL/L) for 2 h. The results showed that linalool treatment disrupted the extracellular lipopolysaccharide synthesis pathway in P. fragi and activated fatty acid metabolism and ribosomal function to compensate for cell membrane damage. The energy metabolism of P. fragi was severely disturbed by linalool, and multiple ATP synthases and ATP transportases were overexpressed in the cells but could not guarantee the consumption of ATP. The simultaneous overexpression of multiple ribosomal functional proteins and transporters may also place an additional burden on cells and cause them to collapse.

In this study, a system was designed that can encapsulate and deliver gallic acid (GA), which was composed of polysaccharide polymers based on sodium alginate (SA), carboxymethyl chitosan (CCT), and cellulose nanofibers (CN) and was assisted by porous starch. The compositions were characterized by rheology and zeta potentials, and the results showed that the materials used in this study could effectively guarantee the stability of the system. The morphology and chemical structure of the beads were characterized by SEM and FT-IR, the results indicated that the addition of CCT could effectively reduce the cracks and pores on the surface of the beads, which was beneficial to the encapsulation and delivery of GA. Moreover, the results of the swelling rate, release tests, and antioxidant tests also proved the effectiveness of the system. The pH response effect of SA/CN/CCT (SCC) beads and the protection of GA were superior, and the release rate of GA in simulated gastric fluid (SGF) was only 6.95%, while SA and SA/CN (SCN) beads reached 57.94% and 78.49%, respectively. In conclusion, the interpenetrating network polymers constructed by SA, CCT, and CN, which, combined with porous starch as a coating layer, can achieve the embedding and the delivery of GA.

Coconut (Cocos nucifera L.) is one of the most critical economic crops in the tropics and sub-tropics. Although coconut protein has attracted more and more attention due to its nutritional potential, the lack of proteomic information has limited its practical application. The present study aimed to investigate the coconut meat proteome by shotgun proteomics and protein-based bioinformatic analysis. A grand total of 1686 proteins were identified by searching the National Center for Biotechnology Information (NCBI) protein database and self-constructed C. nucifera transcriptome repository. Among them, 17 and 9 proteins were identified as antioxidant proteins and globulins, respectively. Network analysis of the globulins referred to the sub-works of Cupin and Oleosin, and the antioxidant proteins were related to the sub-networks of glutathione metabolism and peroxisome. The bioactive peptides acquired by in-silico digestion of the targeted proteins have the potential to be applied as antioxidants and emulsifiers for both healthcare and food stabilization.

In the food industry, coconut milk has a unique flavor and rich nutritional value. However, the poor emulsifying properties of coconut proteins restrict its development. In this study, the effect of ultrasound combined with preheating on coconut globulin and coconut milk was evaluated by physicochemical properties and structural characteristics. The results showed that ultrasound and 90 °C preheating gave coconut protein better emulsifying and thermal properties, demonstrated by higher solubility (45.2% to 53.5%), fewer free sulfhydryl groups (33.24 to 28.05 μmol/g) and higher surface hydrophobicity (7658.6 to 10,815.1). Additionally, Fourier transform infrared spectroscopy and scanning electron microscopy showed obvious changes in the secondary structure. Furthermore, the change in the physicochemical properties of the protein brought a higher zeta potential (−11 to −23 mV), decreased the thermal aggregation rate (148.5% to 13.4%) and increased the viscosity (126.9 to 1103.0 m·Pa·s) of the coconut milk, which indicates that ultrasound combined with preheating treatment provided coconut milk with better thermal stability. In conclusion, ultrasound combined with preheating will have a better influence on modifying coconut globulin and increasing the thermal stability of coconut milk. This study provides evidence that ultrasound and other modification technologies can be combined to solve the problems encountered in the processing of coconut protein products.

The current research aimed to solve the environmental pollution of mature coconut water by Lipomyces starkeyi and provide a study of its high value utilization. The innovation firstly investigated the rheological properties and interface behavior of a crude exopolysaccharide and provided a technical support for its application in food. A response surface methodology was performed to ameliorate the fermentation factors of the new exopolysaccharide with mature coconut water as a substrate, and the consequences suggested that the maximum yield was 7.76 g/L under optimal conditions. Rotary shear measurements were used to study the influence of four variables on the viscosity of the exopolysaccharide solution. The results illustrated that the exopolysaccharide solution demonstrated a shear-thinning behavior and satisfactory thermal stability within the test range. The viscosity of the exopolysaccharide solution was significantly affected by ionic strength and pH; it reached the peak viscosity when the concentration of NaCl was 0.1 mol/L and the pH was neutral. The adsorption behavior of the exopolysaccharide at the medium chain triglyceride–water interface was investigated by a quartz crystal microbalance with a dissipation detector. The results demonstrated that the exopolysaccharide might form a multilayer adsorption layer, and the thickness of the adsorption layer was at its maximum at a concentration of 1.0%, while the interfacial film was the most rigid at a concentration of 0.4%. Overall, these results suggest that the exopolysaccharide produced by Lipomyces starkeyi is an excellent biomaterial for usage in drink, makeup and drug fabrications as a thickening and stabilizing agent.

With the rapid development of the internet of things, there are more and more end devices, such as wearable devices, USVs and intelligent automobiles, connected to the internet. These devices tend to require large amounts of computing resources with stringent latency requirements, which inevitably increases the burden on edge server nodes. Therefore, in order to alleviate the problem that the computing capacity of edge server nodes is limited and cannot meet the computing service requirements of a large number of end devices in the internet of things scenario, we combined the characteristics of rich computing resources of cloud servers and low transmission delay of edge servers to build a hybrid computing task-offloading architecture of cloud-edge-end collaboration. Then, we study offloading based on this architecture for complex dependent tasks generated on end devices. We introduce a two-dimensional offloading decision factor to model latency and energy consumption, and formalize the model as a multi-objective optimization problem with the optimization objective of minimizing the average latency and average energy consumption of the task’s computation offloading. Based on this, we propose a multi-objective offloading (SPMOO) algorithm based on an improved strength Pareto evolutionary algorithm (SPEA2) for solving the problem. A large number of experimental results show that the algorithm proposed in this paper has good performance.

In IoT (Internet of Things) edge computing, task offloading can lead to additional transmission delays and transmission energy consumption. To reduce the cost of resources required for task offloading and improve the utilization of server resources, in this paper, we model the task offloading problem as a joint decision making problem for cost minimization, which integrates the processing latency, processing energy consumption, and the task throw rate of latency-sensitive tasks. The Online Predictive Offloading (OPO) algorithm based on Deep Reinforcement Learning (DRL) and Long Short-Term Memory (LSTM) networks is proposed to solve the above task offloading decision problem. In the training phase of the model, this algorithm predicts the load of the edge server in real-time with the LSTM algorithm, which effectively improves the convergence accuracy and convergence speed of the DRL algorithm in the offloading process. In the testing phase, the LSTM network is used to predict the characteristics of the next task, and then the computational resources are allocated for the task in advance by the DRL decision model, thus further reducing the response delay of the task and enhancing the offloading performance of the system. The experimental evaluation shows that this algorithm can effectively reduce the average latency by 6.25%, the offloading cost by 25.6%, and the task throw rate by 31.7%.

Pseudomonas lundensis is the main bacterium responsible for meat spoilage and its control is of great significance. 3-Carene, a natural monoterpene, has been proved to possess antimicrobial activities. This study aimed to investigate the antibacterial activity and mechanism of 3-carene against the meat spoilage bacterium P. lundensis, and explore its application on pork. After 3-carene treatment, cellular structural changes were observed. Cell walls and membranes were destroyed, resulting in the leakage of alkaline phosphatase and cellular contents. The decreased activity of Ca2+-Mg2+-ATPase and Na+-K+-ATPase showed the imbalance of intracellular ions. Subsequently, adenosine triphosphate (ATP) content and oxidative respiratory metabolism characteristics indicated that 3-carene inhibited the metabolism of the tricarboxylic acid cycle in P. lundensis. The results of binding 3-carene with the vital proteins (MurA, OmpW, and AtpD) related to the formation of the cell wall, the composition of the cell membrane, and the synthesis of ATP further suggested that 3-carene possibly affected the normal function of those proteins. In addition, the growth of P. lundensis and increase in pH were inhibited in pork during the 5 days of cold storage after the samples were pre-treated with 3-carene. These results show the anti-P. lundensis activity and mechanism of 3-carene, and its potential use in meat preservation under refrigerated conditions.

An emulsifier with a targeted antioxidant effect was prepared using the inclusion complexes of octenyl succinic anhydride (OSA)-modified cassava amylose (CA) and quercetin (Q). The designed emulsifier, a carbohydrate polymer-flavonoid complex, exhibited both amphiphilic and antioxidant properties. To investigate the physical and oxidation stabilities of the prepared emulsion, three types of emulsions were prepared: primary emulsions stabilized by enzyme-modified starch, secondary emulsions stabilized by OSA-CA, and tertiary emulsions stabilized by Q-encapsulated complexes (OSA-CA/Q). The structural characteristics of CA, OSA-CA, and OSA-CA/Q were investigated by scanning electron microscopy, Fourier transform infrared spectrometry, and small-angle X-ray scattering analysis. The stabilities of the emulsions were evaluated based on their particle size distribution, zeta potential, creaming stability, and peroxide value. The results showed that the secondary and tertiary emulsions exhibited a relatively narrower particle size distribution than the primary emulsions, but the particle size distribution of the tertiary emulsions was the narrowest (10.42 μm). Moreover, the secondary and tertiary emulsions had lower delamination indices than the primary emulsions after 7 days of storage. The results obtained from the antioxidant experiments indicated that OSA-CA/Q exhibited good oxidation stability for application in emulsion systems.

The effect of the dosage of sulphur-containing tailings (STs) and curing temperature on the properties of M32.5 cement mortar was studied in this work. An experimental study was conducted to evaluate the effects of STs with different substitution ratios (0, 10%, 20%, 30%, 40%) on the compressive strength experiment, fluidity, expansion ratio, and pore structure of M32.5 cement mortar. The results showed that the addition of STs reduced the fluidity of mortar, and the fluidity decreased with the increase of the STs dosage. The compressive strength of mortars increased at a lower substitution rate (0~20%) but decreased at a higher substitution rate (>20%). Ettringite peaks and new sulfate peaks were found by X-ray diffraction (XRD) analysis. Scanning electron microscope (SEM) observation of the microstructure showed that a large number of hydrated products, such as ettringite, formed and filled in the interstitial space, which was conducive to the development of strength. The optimal STs replacement ratio of river sand was 10%. Then, the performance of mortar at curing temperatures of 23 ± 1, 40, 60, and 80 °C was further investigated under the optimal STs replacement ratio. Under high-temperature curing conditions, the early strength of M32.5 cement mortar with STs increased greatly, but the late strength decreased gradually with the increase in curing temperature. The early strength development of the mortar mainly depended on the high speed of hydration reaction, and the late strength variation was mainly affected by hydration products and the pore size distribution. After comprehensive consideration, the optimal curing temperature of M32.5 cement mortar with STs was 40 °C.

The present study aimed to evaluate the rheological and interfacial behaviors of a novel microbial exopolysaccharide fermented by L. starkeyi (LSEP). The structure of LSEP was measured by LC-MS, 1H and 13C NMR spectra, and FT-IR. Results showed that the monosaccharide composition of LSEP was D-mannose (8.53%), D-glucose (79.25%), D-galactose (7.15%), and L-arabinose (5.07%); there existed the anomeric proton of α-configuration and the anomeric carbon of α- and β-configuration; there appeared the characteristic absorption peak of the phosphate ester bond. The molecular weight of LSEP was 401.8 kDa. The water holding capacity (WHC, 2.10 g/g) and oil holding capacity (OHC, 12.89 g/g) were also evaluated. The results of rheological properties showed that the aqueous solution of LSEP was a non-Newtonian fluid, exhibiting the shear-thinning characteristics. The adsorption of LSEP can reduce the interfacial tension (11.64 mN/m) well and form an elastic interface layer at the MCT–water interface. Such functional properties make LSEP a good candidate for use as thickener, gelling agent, and emulsifier to form long-term emulsions for food, pharmaceutical, and cosmetic products.

The contribution of rheological properties and viscoelasticity of the interfacial adsorbed layer to the emulsification mechanism of enzymatic modified sugar beet pectin (SBP) was studied. The component content of each enzymatic modified pectin was lower than that of untreated SBP. Protein and ferulic acid decreased from 5.52% and 1.08% to 0.54% and 0.13%, respectively, resulting in a decrease in thermal stability, apparent viscosity, and molecular weight (Mw). The dynamic interfacial rheological properties showed that the interfacial pressure and modulus (E) decreased significantly with the decrease of functional groups (especially proteins), which also led to the bimodal distribution of particle size. These results indicated that the superior emulsification property of SBP is mainly determined by proteins, followed by ferulic acid, and the existence of other functional groups also promotes the emulsification property of SBP.

The demand for reduced chemical preservative usage is currently growing, and natural preservatives are being developed to protect seafood. With its excellent antibacterial properties, linalool has been utilized widely in industries. However, its antibacterial mechanisms remain poorly studied. Here, untargeted metabolomics was applied to explore the mechanism of Shewanella putrefaciens cells treated with linalool. Results showed that linalool exhibited remarkable antibacterial activity against S. putrefaciens, with 1.5 µL/mL minimum inhibitory concentration (MIC). The growth of S. putrefaciens was suppressed completely at 1/2 MIC and 1 MIC levels. Linalool treatment reduced the membrane potential (MP); caused the leakage of alkaline phosphatase (AKP); and released the DNA, RNA, and proteins of S. putrefaciens, thus destroying the cell structure and expelling the cytoplasmic content. A total of 170 differential metabolites (DMs) were screened using metabolomics analysis, among which 81 species were upregulated and 89 species were downregulated after linalool treatment. These DMs are closely related to the tricarboxylic acid (TCA) cycle, glycolysis, amino acid metabolism, pantothenate and CoA biosynthesis, aminoacyl-tRNA biosynthesis, and glycerophospholipid metabolism. In addition, linalool substantially affected the activity of key enzymes, such as succinate dehydrogenase (SDH), pyruvate kinase (PK), ATPase, and respiratory chain dehydrogenase. The results provided some insights into the antibacterial mechanism of linalool against S. putrefaciens and are important for the development and application of linalool in seafood preservation.

Alkali activated slag (AAS) mortar is becoming an increasingly popular green building material because of its excellent engineering properties and low CO2 emissions, promising to replace ordinary Portland cement (OPC) mortar. However, AAS’s high shrinkage and short setting time are the important reasons to limit its wide application in engineering. This paper was conducted to investigate the effect of internal curing(IC) by super absorbent polymer (SAP) on the autogenous shrinkage of AAS mortars. For this, an experimental study was carried out to evaluate the effect of SAP dosage on the setting time, autogenous shrinkage, compressive strength, microstructure, and pore structure. The SAP were incorporated at different dosage of 0, 0.05, 0.1, 0.2, 0.3, 0.4, and 0.5 percent by weight of slag. The workability, physical (porosity), mechanical, and shrinkage properties of the mortars were evaluated, and a complementary study on microstructure was made. The results indicated that the setting time increased with an increase of SAP dosage due to the additional activator released by SAP. Autogenous shrinkage decreased with an increase of SAP dosage, and was mitigated completely when the dosage of SAP ≥ 0.2% wt of slag. Although IC by means of SAP reduced the compressive strength, this reduction (23% at 56 days for 0.2% SAP) was acceptable given the important role that it played on mitigating autogenous shrinkage. In the research, the 0.2% SAP dosage was the optimal content. The results can provide data and basis for practical application of AAS mortar.

Dendrobium officinale, a precious herbal medicine, has been used for a long time in Chinese history. The metabolites of D. officinale, regarded as its effective components to fight diseases, are significantly affected by cultivation substrates. In this study, ultra-performance liquid chromatography mass spectrometry (UPLC-MS/MS) was conducted to analyze D. officinale stems cultured in three different substrates: pine bark (PB), coconut coir (CC), and a pine bark: coconut coir 1:1 mix (PC). A total of 529 metabolites were identified. Multivariate statistical analysis methods were employed to analyze the difference in the content of metabolites extracted from different groups. By the criteria of variable importance in projection (VIP) value ≥1 and absolute log2 (fold change) ≥1, there were a total of 68, 51, and 57 metabolites, with significant differences in content across groups being filtrated out between PB and PC, PB and CC, and PC and CC, respectively. The comparisons among the three groups revealed that flavonoids were the metabolites that fluctuated most. The results suggested the D. officinale stems from the PB group possessed a higher flavonoid content. Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis indicated that the significantly regulated metabolites were mainly connected with flavonoid biosynthesis. A comprehensive profile of the metabolic differentiation of D. officinale planted in different substrates was provided, which supports the selection of an optimum cultivation substrate for a higher biomass yield of D. officinale.

Characteristic aromas are usually key labels for food products. In this study, the volatile profiles and marker substances of coconut jam during concentration were characterized via sensory evaluation combined with headspace solid phase microextraction-gas chromatography-tandem mass spectrometry (HSPME/GC-MS). A total of 33 aroma compounds were detected by HSPME/GC-MS. Principal component analysis revealed the concentration process of coconut jam can be divided into three stages. In the first stage, esters and alcohols were the two main contributors to the aroma of the coconut jam. Next, a caramel smell was gradually formed during the second stage, which was mainly derived from aldehydes, ketones and alcohols. The concentration of aldehydes increased gradually at this stage, which may be the result of a combination of the Maillard reaction and the caramelization reaction. In the final sterilization stage, the ‘odor intensity’ of caramel reached the maximum level and a variety of aroma compounds were produced, thereby forming a unique flavor for the coconut jam. Finally, furfural fit a logistic model with a regression coefficient (r2) of 0.97034. Therefore, furfural can be used as a marker substance for monitoring the concentration of coconut jam.

Vitamin E (VE) and β-cyclodextrin (β-CD) can form an inclusion complex; however, the inclusion rate is low because of the weak interaction between VE and β-CD. The results of a molecular docking study showed that the oxygen atom in the five-membered ring of octenyl succinic anhydride (OSA) formed a strong hydrogen bond interaction (1.89 Å) with the hydrogen atom in the hydroxyl group of C-6. Therefore, β-CD was modified using OSA to produce octenyl succinic-β-cyclodextrin (OCD). The inclusion complexes were then prepared using OCD with VE. The properties of the inclusion complex were investigated by Fourier-transform infrared spectroscopy (FT-IR), 13C CP/MAS NMR, scanning electron microscopy (SEM), and atomic force microscopy (AFM). The results demonstrated that VE had been embedded into the cavity of OCD. Furthermore, the emulsifying properties (particle size distribution, ζ-potential, and creaming index) of the OCD/VE inclusion-complex-stabilized emulsion were compared with that stabilized by β-CD, OCD, and an OCD/VE physical mixture. The results showed that the introduction of the OS group and VE could improve the physical stability of the emulsion. In addition, the OCD/VE inclusion complex showed the strongest ability to protect the oil in the emulsion from oxidation. OCD/VE inclusion complex was able to improve the physical and oxidative stability of the emulsion, which is of great significance to the food industry.

Tender coconut water tastes sweet and is enjoyed by consumers, but its commercial development is restricted by an extremely short shelf life, which cannot be explained by existing research. UPLC-MS/MS-based metabolomics methods were used to identify and statistically analyze metabolites in coconut water under refrigerated storage. A multivariate statistical analysis method was used to analyze the UPLC-MS/MS datasets from 35 tender coconut water samples stored for 0−6 weeks. In addition, we identified other differentially expressed metabolites by selecting p-values and fold changes. Hierarchical cluster analysis and association analysis were performed with the differentially expressed metabolites. Metabolic pathways were analyzed using the KEGG database and the MetPA module of MetaboAnalyst. A total of 72 differentially expressed metabolites were identified in all groups. The OPLS-DA score chart showed that all samples were well grouped. Thirty-one metabolic pathways were enriched in the week 0−1 samples. The results showed that after a tender coconut is peeled, the maximum storage time at 4 °C is 1 week. Analysis of metabolic pathways related to coconut water storage using the KEGG and MetPA databases revealed that amino acid metabolism is one of the main causes of coconut water quality deterioration.

3-Carene is an antimicrobial monoterpene that occurs naturally in a variety of plants and has an ambiguous antibacterial mechanism against food-borne germs. The antibacterial effects and action mechanism of 3-carene against Gram-positive Brochothrix thermosphacta ACCC 03870 and Gram-negative Pseudomonas fluorescens ATCC 13525 were studied. Scanning electron microscopy (SEM) examination and leakage of alkaline phosphatase (AKP) verified that 3-carene caused more obvious damage to the morphology and wall structure of B. thermosphacta than P. fluorescens. The release of potassium ions and proteins, the reduction in membrane potential (MP), and fluorescein diacetate (FDA) staining further confirmed that the loss of the barrier function of the cell membrane and the leakage of cytoplasmic contents were due to the 3-carene treatment. Furthermore, the disorder of succinate dehydrogenase (SDH), malate dehydrogenase (MDH), pyruvate kinase (PK), and ATP content indicated that 3-carene could lead to metabolic dysfunction and inhibit energy synthesis. In addition, the results from the fluorescence analysis revealed that 3-carene could probably bind to bacterial DNA and affect the conformation and structure of genomic DNA. These results revealed that 3-carene had strong antibacterial activity against B. thermosphacta and P. fluorescens via membrane damage, bacterial metabolic perturbations, and genomic DNA structure disruption, interfering in cellular functions and even causing cell death.

The aim of this work was to compare the composition and physicochemical properties (SEM, XRD, solubility, swelling power, paste clarity, retrogradation, freeze−thaw stability, thermal property, and pasting property) of three Chinese yam (Dioscorea opposita Thunb.) starches (CYYS-1, CYYS-2, and CYYS-3) in Yunlong town, Haikou, Hainan Province, China. Our results show that all the CYYS gave a typical C-type X-ray diffraction pattern. The swelling power of CYYS varied from 10.79% to 30.34%, whereas solubility index was in the range of 7.84−4.55%. The freeze−thaw stability of each CYYS showed a contrary tendency with its amylose content. In addition, CYYS-3 showed the highest To (81.1 °C), Tp (84.8 °C), Tc (91.2 °C), and ΔH (14.1 J/g). The pasting temperature of CYYS-1 increased significantly with sucrose addition. NaCl could inhibit the swelling power of CYYS. There were significant decreases in pasting temperature and pasting time of CYYS when pH decreased.

Concentrated coconut milk (CCM), a raw material from coconut products, is extremely unstable because of its high oil content (>30%). In this study, three model emulsions—primary emulsions stabilized by coconut proteins only, secondary emulsions stabilized by the conjugation of sugar beet pectin (SBP) and coconut protein, and laccase-treated secondary emulsions—were prepared to investigate the effects of different factors (coconut proteins, coconut proteins + SBP, laccase-treated emulsions) on the stability of model emulsions and the application of this method to real CCM. The stability of the emulsions was evaluated based on their interfacial tension, zeta potential, particle size distribution, rheological properties, and the assembly formation of SBP and coconut protein at the oil–water interface. Results showed that addition of SBP or laccase can increase the viscosity and reduce the interfacial tension of the emulsion, and the effect was concentration dependent. Zeta potential of the emulsion decreased with the increase of protein (from −16 to −32 mV) and addition of SBP (from −32 to −46 mV), and it was reduced when laccase was added (from −9.5 to −6.0 mV). The secondary emulsion exhibited the narrowest particle size distribution (from 0.1 to 20 μm); however, laccase-catalyzed secondary emulsions showed the best storage stability and no layering when the laccase content reached 10 U/100 g. Confocal laser scanning microscopy (CLSM) revealed that protein was adsorbed on the oil–water interface and SBP distributed in the continuous phase could undergo oxidative crosslinking by laccase. These results show that the stability of the concentrated emulsion can be effectively improved by adding SBP and laccase.

Tomato juice was fermented by Lactobacillus plantarum and Lactobacillus casei to produce an innovative high-bioactivity probiotic beverage. The levels of lycopene, total carotenoids, ascorbic acid, total phenolic and volatile compounds, 1,1-diphenyl-2-picrylhydrazyl (DPPH), 2,2’-azinobis-3-ethylbenzotiazo-line-6-sulfonic acid (ABTS) radical scavenging capacities, ferric reducing antioxidant power (FRAP), and Escherichia coli flora, as well as the inhibition of copper-induced human low-density lipoproteins (LDL)-cholesterol oxidation assays, were measured. The results revealed that the ABTS and DPPH inhibition values, as well as the FRAP and total phenolic content, were significantly increased. LDL-cholesterol oxidation was markedly delayed after the addition of the fermented juice. The in vitro inhibitory effects of Escherichia coli flora were substantially increased after being fermented with Lactobacillus plantarum and Lactobacillus casei. The results associated with the volatile compounds indicated that fermentation with Lactobacillus plantarum and Lactobacillus casei is a meaningful strategy for modifying flavors.

The recovery of vanadium from titanium tetrachloride tail residue is a resource-efficient and environment-friendly method for treating hazardous vanadium-containing solid waste. In this study, to maximize the recovery rate of vanadium in the vanadium extraction process, the independent calcination and leaching factors were optimized using response surface methodology, in terms of calcination temperature (750–950 °C), calcination time (60–180 min), leaching liquid–solid ratio (5–25 mL/g), and leaching time (30–150 min). The results revealed that the calcination temperature was the most effective parameter for vanadium recovery, while the liquid–solid ratio was the least effective factor. Additionally, the optimal conditions were identified as a calcination temperature of 937 °C, a calcination time of 150 min, a leaching solid-to-liquid ratio of 17.4 mL/g, and a leaching time of 150 min. The maximum predicted recovery rate of vanadium by the model regression equation reached 93.1% and showed high credibility consistent with the experimental recovery rate of 93%.

The hydrophobicity of a support plays a critical role in the catalytic efficiency of immobilized lipases. 3-aminopropyltriethoxysilane (APTES)-modified silica clay (A-SC) was coupled with silane coupling agents of different alkyl chains (methyl triethoxysilane, vinyl triethoxysilane, octyl triethoxysilane, and dodecyl triethoxysilane) to prepare a series of hydrophobic support for lipase immobilization. The lipases were immobilized onto the support by conducting glutaraldehyde cross-linking processes. The results showed that the activity of the immobilized biocatalyst increased with hydrophobicity. The hydrolytic activity of Lip-Glu-C12-SC (contact angle 119.8°) can reach 5900 U/g, which was about three times that of Lip-Glu-A-SC (contact angle 46.5°). The immobilized lipase was applied as a biocatalyst for biodiesel production. The results showed that the catalytic yield of biodiesel with highly hydrophobic Lip-Glu-C12-SC could be as high as 96%, which is about 30% higher than that of Lip-Glu-A-SC. After being recycled five times, the immobilized lipase still maintained good catalytic activity and stability. This study provides a good strategy to improve the efficiency of immobilized lipases, showing great potential for future industrial application on biodiesel production.

Magnetic nanoparticles (MNp) Fe3O4 were prepared by chemical coprecipitation, and introduced onto collagen fibers to form magnetic collagen support (MNp-Col) for enzyme immobilization. Candida rugosa lipase has been successfully immobilized on MNp-Col supports by a covalent bond cross-linking agent, glutaraldehyde. The characteristics of MNp-Col and the immobilized lipase were investigated. The immobilized lipase displayed sound magnetic separation abilities in both aqueous and organic media. The activity of the immobilized lipase reached 2390 U/g under optimal conditions. The MNp-Col immobilized lipase shows broadened temperature and pH ranges for hydrolysis of olive oil emulsion. For synthesis of butyrate esters in an n-hexane medium, the yield changes through use of different alcohols, among which, butyric butyrate showed the highest yield. The prepared magnetic collagen fiber provides separation support for enzyme immobilization and has the potential to be used in other biotechnology fields.