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BACKGROUND: 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. RESULTS: 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. CONCLUSION: 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.
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The surface of food processing equipment is easily affected by biofilm-forming bacteria, leading to cross-contamination and food safety hazards. The critical issue is how to endow the surface of contact materials with antibacterial and antibiofilm abilities. A sustainable, stable, and antibiofilm coating was prepared by phase transition of glutenin. The disulfide bonds in glutenin were reduced by tris(2-carboxyethyl)phosphine, triggering the phase transition of glutenin. Hydrophobic interactions and intermolecular disulfide bonds may be the primary forces. Furthermore, the phase-transited products formed a nanoscale coating on the surface of stainless steel and glass under their own adhesion force and gravity. The coating exhibited good stability in harsh environments. More importantly, after 3 h of direct contact, the colony of Escherichia coli and Staphylococcus aureus decreased by one logarithm. The amount of biofilm was observed to be significantly decreased through optical microscopy and scanning electron microscopy. This article provides a foundational module for developing novel coatings.
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Antibacterianos , Biopelículas , Escherichia coli , Staphylococcus aureus , Antibacterianos/farmacología , Antibacterianos/química , Adhesión Bacteriana/efectos de los fármacos , Biopelículas/efectos de los fármacos , Biopelículas/crecimiento & desarrollo , Materiales Biocompatibles Revestidos/química , Materiales Biocompatibles Revestidos/farmacología , Escherichia coli/efectos de los fármacos , Interacciones Hidrofóbicas e Hidrofílicas , Transición de Fase , Acero Inoxidable/química , Staphylococcus aureus/efectos de los fármacos , Propiedades de SuperficieRESUMEN
Matrix effects limit the application of surface-enhanced Raman scattering (SERS) technology in the field of food safety. This study elucidated it from the perspective of protein corona by employing a model system for melamine SERS detection in milk. Compared with the melamine standard solution, higher detection limits (1 mg/L and 10 mg/L) are observed in milk matrix. The melamine signal exhibits an 80% reduction in whey protein solution, suggesting that protein has a significant impact on SERS signals. The changes in particle size, zeta potential and UV-vis spectra indicate the AuNPs interact with whey protein. Forming protein corona inhibits the melamine-induced AuNPs aggregation, reducing the number of 'hot spot' and the adsorption of melamine on AuNPs (from 0.28 mg/L to 0.07 mg/L), which may be responsible for signal loss. The found matrix effect from protein corona provides new insights for developing strategies about reducing matrix effect in SERS application.
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Contaminación de Alimentos , Oro , Leche , Corona de Proteínas , Espectrometría Raman , Triazinas , Triazinas/química , Triazinas/análisis , Espectrometría Raman/métodos , Animales , Leche/química , Contaminación de Alimentos/análisis , Corona de Proteínas/química , Corona de Proteínas/análisis , Oro/química , Nanopartículas del Metal/química , BovinosRESUMEN
Previous research on pesticides in green tea mainly focused on detection technology but lacked insights into pesticide use during cultivation. To address this gap, a survey was conducted among Rizhao green tea farmers. The survey results showed that most tea farmers were approximately 60 years old and managed small, scattered tea gardens (< 0.067 ha). Notably, tea farmers who had received agricultural training executed more standardized pesticide application practices. Matrine and thiazinone are the most used pesticides. A total of 16 types of pesticides were detected in the tested green tea samples, with 65% of the samples containing residues of at least one pesticide. Notably, higher levels of residues were observed for bifenthrin, cyfluthrin, and acetamiprid. The presence of pesticide residues varied significantly between seasons and regions. The risk assessment results indicated that the hazard quotient (HQ) values for all 16 pesticides detected in green tea were < 1, suggesting that these residue levels do not pose a significant public health concern.
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Residuos de Plaguicidas , Plaguicidas , Té , Té/química , Medición de Riesgo , Plaguicidas/análisis , Residuos de Plaguicidas/análisis , Monitoreo del Ambiente , Humanos , Agricultores , Agricultura , Camellia sinensis/química , Piretrinas/análisis , China , Exposición Profesional/análisisRESUMEN
The distribution fate of chlorothalonil (CHT) in the environment (soil and water) and fruits is controlled by the capacity of cuticles to adsorb and desorb CHT, which directly affects the safety of both the environment and fruits. Batch experiments were conducted to reveal the adsorption-desorption behaviors of CHT in the cuticles of apple and red jujube. The adsorption kinetics showed that both physisorption and chemisorption occurred during the adsorption process. Furthermore, the isothermal adsorption of CHT in the fruit cuticles followed the Freundlich model. The thermodynamic parameters (ΔG ≤ -26.16 kJ/mol, ΔH ≥ 31.05 kJ/mol, ΔS ≥ 0.20 kJ/(mol K) showed that the whole CHT adsorption process was spontaneous, and the hydrophobic interaction was predominant. The CHT adsorption capacity of the apple cuticle was higher than that of the red jujube cuticle, potentially due to the significantly higher alkanes content of apples than that of red jujubes. An appropriate ionic strength (0.01 moL/L) could induce a higher adsorption capacity. In addition, the desorption kinetics were shown to conform to a Quasi-first-order model, meaning that not all the adsorbed CHT could be easily desorbed. The desorption ratios in apple and red jujube cuticles were 41.38% and 35.64%, respectively. The results of Fourier-transformed infrared spectroscopy and X-ray photoelectron spectroscopy further confirmed that CHT could be adsorbed and retained in the fruit cuticles. Investigating the adsorption-desorption behavior of CHT in the apple and red jujube cuticles allowed to determine the ratio of its final distribution in the fruits and environment, providing a theoretical basis to evaluate the risk of residue pesticide.
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Frutas , Malus , Nitrilos , Ziziphus , Adsorción , Ziziphus/química , Malus/química , Nitrilos/química , Frutas/química , Cinética , Fungicidas Industriales/químicaRESUMEN
Dry-aged beef has been long favored by people due to its unique flavor and taste. However, the inner relationship between its overall quality formation and microbial changes during dry aging has not yet received much attention and research. To deeply reveal the forming mechanism of the unique flavor and taste of dry-aged beef, correlations between its three main quality indicators, i.e., texture, free amino acids (FAAs), volatile flavor compounds (VFCs), and microbial succession were analyzed in this study. The results showed that Staphylococcus spp. and Macrococcus spp. were key strains that influenced the total quality of dry-aged beef and strongly correlated with chewiness, hardness, and sweet FAAs (Ala), providing beef with unique palatability and taste. Additionally, among VFCs, Staphylococcus spp. and Macrococcus spp. showed a strong correlation with octanal and heptanal, and meanwhile, those highly correlated with nonanal, pentanol, and oct-1-en-3-ol were Debaryomyces spp., Psychrobacter spp., and Brochothrix spp., respectively, providing beef with a unique flavor. Staphylococcus spp. was proposed to be the dominant genus for dry-aged beef. This study provides valuable reference for the understanding of the role of microorganisms involved in dry aging.
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Based on the fact that not all chemical substances possess good Raman signals, this article focuses on the Raman silent region signals of pesticides with cyano group. Under the optimized conditions of methanol-water (1:1, v/v) as the solvent, irradiation at 302 nm light source for 20 min, and the use of 0.5 mol/L KI as the aggregating agent, Surface-enhanced Raman spectroscopy (SERS) method for azoxystrobin detection was developed by the Raman silent region signal of 2230 cm-1, and verified by detecting the spiked grapes with different concentrations of azoxystrobin. Other four pesticides with cyano group also could be identified at the peak of 2180 cm-1, 2205 cm-1, 2125 cm-1, and 2130 cm-1 for acetamiprid, phoxim, thiacloprid and cymoxanil, respectively. When azoxystrobin or acetamiprid was mixed respectively with chlorpyrifos without cyano group, their SERS signals in the Raman silent region of chlorpyrifos were not interfered, while mixed with cymoxanil in different ratios (1:4, 1:1 and 4:1), respectively, each two pesticides with cyano group could be distinguished by the changes in the Raman silent region. In further, four pesticides with or without cyano group were mixed together in 1:1:1:1 (acetamiprid, cymoxanil, azoxystrobin chlorpyrifos), and each pesticide still could be identified even at 0.5 mg/L. The results showed that the SERS method combined with UV irradiation may provide a new way to monitor the pesticides with C≡N performance in the Raman silent region without interference from the food matrix.
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Plaguicidas , Espectrometría Raman , Estrobilurinas , Espectrometría Raman/métodos , Plaguicidas/análisis , Estrobilurinas/análisis , Pirimidinas/análisis , Pirimidinas/química , Vitis/química , Metacrilatos/química , Metacrilatos/análisis , Neonicotinoides/análisisRESUMEN
A fluorescent immunosorbent assay incorporating signal amplification away from the surface of spherical nucleic acid (SNA) was developed for the detection of chloramphenicol (CAP). Through the conjugation of antibodies and poly-adenine (polyA) DNA onto the surface of gold nanoparticles (AuNPs), the fabrication of the nano-immunoprobe was achieved in a more straightforward and cost-effective manner. Moreover, a strategy utilizing the hybridization chain reaction (HCR) in the amplification step was devised, with particular attention given to the enzyme inhibition associated with SNA. The results demonstrated good performance on CAP detection with a linear range of 0.01-5 ng/L with a detection limit of 0.005 ng/L. The significance of this work mainly lies in the polyA-SNA-based immunoprobe and the thoughtful design to prevent enzyme inhibition.
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Cloranfenicol , Oro , Nanopartículas del Metal , Cloranfenicol/análisis , Oro/química , Nanopartículas del Metal/química , Poli A/química , Inmunoensayo/métodos , Límite de DetecciónRESUMEN
Echinacea purpurea polysaccharide (EPP) exhibit various pharmacological activities, including immunomodulatory, anti-inflammatory, and anti-tumor effects. In this study, we investigated the potential mechanism of EPP intervention in hepatocellular carcinoma (HCC). The results demonstrated that EPP effectively mitigated liver injury caused by HCC, inhibited the proliferation of HCC, and induced apoptosis. Following EPP intervention, there was a significant increase in propionic acid and butyric acid-producing gut microbiota such as Coprococcus, Clostridium and Roseburia, leading to enhanced expression of intestinal tight junction proteins and the repair of the intestinal barrier. This controls lipopolysaccharide (LPS) leakage, which in turn inhibits the TLR4/NF-κB pathway and reduces the expression of inflammatory factors such as IL-6, as well as migration factors like MMP-2. Metabolomics revealed the downregulation of pyrimidine metabolism and nucleotide metabolism, along with the upregulation of butyrate metabolism in tumor cells. This study demonstrated that EPP effectively regulated LPS leakage by modulating gut microbes, and this modulation influenced the TLR4/NF-κB pathway, ultimately disrupting tumor cell survival induced by HCC in mice.
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Carcinoma Hepatocelular , Echinacea , Microbioma Gastrointestinal , Neoplasias Hepáticas , Animales , Ratones , FN-kappa B/metabolismo , Carcinoma Hepatocelular/tratamiento farmacológico , Carcinoma Hepatocelular/metabolismo , Receptor Toll-Like 4/metabolismo , Lipopolisacáridos/metabolismo , Neoplasias Hepáticas/tratamiento farmacológico , Neoplasias Hepáticas/metabolismo , Polisacáridos/farmacología , Polisacáridos/uso terapéuticoRESUMEN
The effect of tannic acid (TA) binding on the thermal degradation of boscalid was studied in this work. The results revealed that TA binding has a significant impact on boscalid degradation. The degradation rate constant of bound boscalid was reduced, and its corresponding half-life was significantly prolonged compared to the free state. Four identical degradation products were detected in both states through UHPLC-Q-TOF-MS, indicating that degradation products were not affected by TA binding. Based on DFT and MS analysis, the degradation pathways of boscalid included hydroxyl substitution of chlorine atoms and cleavage of CN and CC bonds. The toxicity of B2 and B3 exceeded that of boscalid. In summary, the binding of TA and boscalid significantly affected the thermal degradation rate of boscalid while preserving the types of degradation products. This study contributed to a fundamental understanding of the degradation process of bound pesticide residues in complex food matrices.
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Compuestos de Bifenilo , Niacinamida , Niacinamida/análogos & derivados , Polifenoles , Compuestos de Bifenilo/química , Niacinamida/químicaRESUMEN
Carbofuran and acetamiprid pose the highest residual risk among pesticides found in wolfberries. This study aimed to degrade these pesticides in wolfberries using a multi-array dielectric barrier discharge plasma (DBD), evaluate the impact on safety and quality and explore their degradation mechanism. The results showed that DBD treatment achieved 90.6% and 80.9% degradation rates for carbofuran and acetamiprid, respectively, following a first-order kinetic reaction. The 120 s treatment successfully reduced pesticide contamination to levels below maximum residue limits. Treatment up to 180 s did not adversely affect the quality of wolfberries. QTOF/MS identification and degradation pathway analysis revealed that DBD broke down the furan ring and carbamate group of carbofuran, while replacing the chlorine atom and oxidizing the side chain of acetamiprid, leading to degradation. The toxicological evaluation showed that the degradation products were less toxic than undegraded pesticides. Molecular dynamics simulations revealed the reactive oxygen species (ROS) facilitated the degradation of pesticides through dehydrogenation and radical addition reactions. ROS type and dosage significantly affected the breakage of chemical bonds associated with toxicity (C4-O5 and C2-Cl1). These findings deepen insights into the plasma chemical degradation of pesticides.
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Carbofurano , Lycium , Neonicotinoides , Plaguicidas , Carbofurano/toxicidad , Especies Reactivas de Oxígeno , Simulación de Dinámica Molecular , Plaguicidas/análisisRESUMEN
Aspergillus fumigatus causes life-threatening mold pneumonia in immune compromised patients, particularly in those with quantitative or qualitative defects in neutrophils. While innate immune cell crosstalk licenses neutrophil antifungal activity in the lung, the role of epithelial cells in this process is unknown. Here, we find that that surfactant protein C (SPC)-expressing lung epithelial cells integrate infection-induced IL-1 and type III interferon signaling to produce granulocyte-macrophage colony-stimulating factor (GM-CSF) preferentially at local sites of fungal infection and neutrophil influx. Using in vivo models that distinguish the role of GM-CSF during acute infection from its homeostatic function in alveolar macrophage survival and surfactant catabolism, we demonstrate that epithelial-derived GM-CSF increases the accumulation and fungicidal activity of GM-CSF-responsive neutrophils, with the latter being essential for host survival. Our findings establish SPC + epithelial cells as a central player in regulating the quality and strength of neutrophil-dependent immunity against inhaled mold pathogens. HIGHLIGHTS: GM-CSF is essential for host defense against A. fumigatus in the lung IL-1 and IFN-λ promote GM-CSF production by lung epithelial cells in parallelEpithelial cell-derived GM-CSF increases neutrophil accumulation and fungal killing capacityEpithelial cells preferentially upregulate GM-CSF in local sites of inflammation.
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Ultrasonic treatment is widely used for surface cleaning of vegetables in the processing of agricultural products. In the present study, the molecular and proteomic response of Pseudomonas fluorescens biofilm cultured on lettuce was investigated after ultrasound treatment at different intensity levels. The results show that the biofilm was efficiently removed after ultrasound treatment with intensity higher than 21.06 W/cm2. However, at an intensity of less than 18.42 W/cm2, P. fluorescens was stimulated by ultrasound leading to promoted bacterial growth, extracellular protease activity, extracellular polysaccharide secretion (EPS), and synthesis of acyl-homoserine lactones (AHLs) as quorum-sensing signaling molecules. The expression of biofilm-related genes, stress response, and dual quorum sensing system was upregulated during post-treatment ultrasound. Proteomic analysis showed that ultrasound activated proteins in the flagellar system, which led to changes in bacterial tendency; meanwhile, a large number of proteins in the dual-component system began to be regulated. ABC transporters accelerated the membrane transport of substances inside and outside the cell membrane and equalized the permeability conditions of the cell membrane. In addition, the expression of proteins related to DNA repair was upregulated, suggesting that bacteria repair damaged DNA after ultrasound exposure.
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Lactuca , Pseudomonas fluorescens , Pseudomonas fluorescens/fisiología , Proteómica , Biopelículas , Percepción de QuorumRESUMEN
Phenological models are built upon an understanding of the influence of environmental factors on plant phenology, and serve as effective tools for predicting plant phenological changes. However, the differences in phenological model predictive performance under different climate change scenarios have been rarely studied. In this study, we parameterized thirteen spring phenology models, including six one-phase models and seven two-phase models, by combining phenological observations and meteorological data. Using climatic data from two Shared Socioeconomic Pathways (SSP) scenarios, namely SSP126 (high mitigation and low emission) and SSP585 (no mitigation and high emission), we predicted spring phenology in Germany from 2021 to 2100, and compared the impacts of dormancy phases and driving factors on model predictive performance. The results showed that the average correlation coefficient between the predicted start of growing season (SOS) by the 13 models and the observed values exceeded 0.72, with the highest reaching 0.80. All models outperformed the NULL model (Mean of SOS), and the M1 model (driven by photoperiod and forcing temperature) performed the best for all the tree species. In the SSP126 scenario, the average SOS advanced initially and then gradually shifted towards a delay starting around 2070. In the SSP585 scenario, the average SOS advanced gradually at a rate of approximately 0.14 days per year. Moreover, the standard deviation of the simulated SOS by the 13 spring phenology models exhibited a significant increase at a rate of 0.04 days per year. On average, two-phase models exhibited larger standard deviations than one-phase models after approximately 2050. Models driven solely by temperature showed larger standard deviations after 2060 compared to models driven by both temperature and photoperiod. Our findings suggest investigating the release mechanisms of endodormancy phase and incorporating new insights into future phenological models to better simulate the changes in plant phenology.
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The high photostability of DNAs and RNAs is inextricably related to the photochemical and photophysical properties of their building blocks, nucleobases and nucleosides, which can dissipate the absorbed UV light energy in a harmless manner. The deactivation mechanism of the nucleosides, especially the decay pathways of cytidine (Cyd), has been a matter of intense debate. In the current study, we employ high-level electronic structure calculations combined with excited state non-adiabatic dynamic simulations to provide a clear picture of the excited state deactivation of Cyd in both gas phase and aqueous solution. In both environments, a barrierless decay path driven by the ring-puckering motion and a relaxation channel with a small energy barrier driven by the elongation motion of CîO bond are assigned to <200 fs and sub-picosecond decay time component, respectively. The presence of ribose group has a subtle effect on the dynamic behavior of Cyd in gas phase as the ribose-to-base hydrogen/proton transfer process is energetically inaccessible with a sizable energy barrier of about 1.4 eV. However, this energy barrier is significantly reduced in water, especially when an explicit water molecule is present. Therefore, we argue that the long-lived decay channel found in aqueous solution could be assigned to the Cyd-water intermolecular hydrogen/proton transfer process. The present study postulates a novel scenario toward deep understanding the intrinsic photostability of DNAs and RNAs and provides solid evidence to disclose the long history debate of cytidine excited-state decay mechanism, especially for the assignment of experimentally observed time components.
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Exercise-induced fatigue is a common physiological response to prolonged physical activity, often associated with changes in gut microbiota and metabolic responses. This study investigates the potential role of Brassica rapa L. in modulating these responses. Using an animal model subjected to chronic exercise-induced stress, we explored the effects of Brassica rapa L. on fatigue-related biomarkers, energy metabolism genes, inflammatory responses, intestinal integrity, and gut microbiota composition. Our findings revealed that Brassica rapa L. exhibits significant antioxidant activity and effectively modulates physiological responses to fatigue. It influences gene expression related to the tricarboxylic acid (TCA) cycle in muscle tissue through the AMPK/PGC-1α/TFAM signaling pathway. Furthermore, Brassica rapa L. has been found to alleviate inflammation by inhibiting lipopolysaccharide (LPS) infection and suppressing the activation of the NF-κB pathway. It also maintains intestinal integrity and controls Gram-negative bacterial growth. A correlation analysis identified several pathogenic bacteria linked with inflammation and energy metabolism, as well as beneficial probiotic bacteria associated with improved energy metabolism and reduced inflammation. These findings underscore Brassica rapa L.'s potential for managing prolonged exercise-induced fatigue, paving the way for future therapeutic applications. The results highlight its impact on gut microbiota modulation and its role in nutrition science and sports medicine.
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Brassica rapa , Animales , Inflamación/metabolismo , Antioxidantes/uso terapéutico , Fatiga , Músculos/metabolismoRESUMEN
The transit signal priority leads to the delay of private vehicles in the priority and non-priority phases. To address this problem, a bi-level programming model is proposed based on the dynamic cycle and arrival rate of private vehicles under connected environment. The upper model is built by a delay triangle, with the maximum delay reduction of private vehicles between the decreased delay and increased delay in the experimental period. The lower model is constructed based on the Stackelberg model of game theory, and the objective is to obtain the dynamic cycle. A genetic algorithm (GA) is implemented to solve the proposed model. Based on SUMO, a case study of a self-driving bus in the city of Zhengzhou is conducted to demonstrate the effectiveness of the proposed model. The results from GA and SUMO are consistent, which verifies the effectiveness of the proposed model. The delay of the private vehicles with dynamic signal priority declines by 21.32% on average compared to that without priority. Compared with active signal priority, it declines by 22.63% on average. The proposed method is compared with the method proposed by other papers, and the delay per private vehicle is small. The effectiveness of the proposed method is further illustrated. The proposed methodology is helpful for improving the operation efficiency of intersections with minimum delay.
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Microplastics (MPs) are now not only emerging as pollutants in the environment, but their current state of contamination in food is also a cause for concern. It is necessary to focus how to control, reduce, and even remove MPs. In this study, a magnetic metal-organic framework (MOF) material, Fe3O4@SiO2@MIL-53(Al), was synthesized and applied to simulate the magnetization and removal of four types of MPs. Fe3O4@SiO2@MIL-53(Al) was characterized by various means to demonstrate its successful synthesis as a core-shell nanomaterial. The conditions of the method were optimized by examining the effect of time, the mass ratio of material to MPs, temperature, and pH on the removal effect. The removal rates of four MPs were 54.10-94.17%, and the maximum adsorption capacities of Fe3O4@SiO2@MIL-53(Al) that can be adsorbed were 10511.45-44390.24 mg g-1. Notably, the material can effectively magnetize and remove MPs from liquid food containing alcohol with highest efficiency of 97.10 ± 1.21%. Potential adsorption mechanisms were analyzed using kinetic, isothermal, and thermodynamic models, and electrostatic attraction and hydrogen bonding were found to play a dominant role in the adsorption process. In addition, not only can Fe3O4@SiO2@MIL-53(Al) be reused up to five times to maintain high removal rates, but it can also be used in food systems. Therefore, Fe3O4@SiO2@MIL-53(Al) not only has the advantages of ease of use and stability, but also can efficiently and quickly magnetize and remove many common MPs in more complex matrices such as food.
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Estructuras Metalorgánicas , Contaminantes Químicos del Agua , Estructuras Metalorgánicas/química , Dióxido de Silicio , Microplásticos , Plásticos , Adsorción , Fenómenos Magnéticos , Contaminantes Químicos del Agua/análisisRESUMEN
This study established microbial growth models for fresh-cut cucumber packaged with different O2 transmission rate (OTR) films. Biaxially oriented polyamide/low-density polyethylene (BOPA/LDPE) film (â : OTR5, â £: OTR48) and polyethylene (PE) film (â ¡: OTR2058, â ¢: OTR3875) were used to construct a passive modified atmosphere packaging (MAP). Mathematic models have been established to account for dynamic variations in the O2/CO2 concentration and their impacts on Pseudomonas fluorescens growth. The coupling models included: 1) respiration models of cucumber and P. fluorescens based on Michaëlis-Menten equation, 2) coupling gas exchange models based on Fick's law that contained models of P. fluorescens growth and respiration, 3) coupling microbial growth models contained respiration and gas exchange models. Coupling model with Baranyi function successfully fitted variations of O2/CO2 concentration and P. fluorescens growth in the two packaging. In addition, quality properties of packed fresh-cut cucumber were determined. The film â £ (OTR48) as a high barrier film showed the highest inhibition of P. fluorescens growth, adequately retained its colour, firmness and total soluble solid (TSS) concentration in contrast to the PE films packaging. The constructed coupling models can be utilized for assessing the shelf life and microbial growth of fresh-cut vegetables with spoilage dominated by pseudomonads.
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Cucumis sativus , Pseudomonas fluorescens , Embalaje de Alimentos , Conservación de Alimentos , Dióxido de Carbono , Microbiología de Alimentos , AtmósferaRESUMEN
Cancer phototherapy, including photodynamic therapy (PDT) and photothermal therapy (PTT), has been extensively studied in recent years because of its noninvasive properties, high efficiency, improved selectivity, and reduced side effects. Gold nanoclusters (AuNCs) have the advantages of high biocompatibility, high biosafety, excellent photoresponse, and high tumor penetration ability. This review analyzes the use of AuNCs in tumor phototherapy in recent years from three aspects, namely, AuNCs in PDT, AuNCs in PTT, and AuNCs in combination therapy, and presents the high potential of AuNCs in cancer phototherapy. This review aims to provide readers with the unique advantages, diversified application approaches, and bright application prospects of AuNCs in phototherapy and to provide insights into strategies for applying AuNCs to tumor phototherapy.