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A cannabidiol (CBD)-loaded oil-in-water emulsion stabilized by a whey protein (WP)-maltodextrin (MD) conjugate and rosmarinic acid (RA) complex was fabricated, and its stability characteristics were investigated under various environmental conditions. The WP-MD conjugates were formed via dry-heating. The interaction between WP and MD was assessed by browning intensity, reduced amount of free amino groups, the formation of high molecular weight components in sodium dodecyl sulfate-PAGE, and changes in secondary structure of whey proteins. The WP-MD-RA noncovalent complex was prepared and confirmed by fluorescence quenching and Fourier-transform infrared spectroscopy spectra. Emulsions stabilized by WP, WP-MD, and WP-RA were used as references to evaluate the effect of WP-MD-RA as a novel emulsifier. Results showed that WP-MD-RA was an effective emulsifier to produce fine droplets for a CBD-loaded emulsion and remarkably improved the pH and salt stabilities of emulsions in comparison with WP. An emulsion prepared with WP-MD-RA showed the highest protection of CBD against UV and heat-induced degradation among all emulsions. The ternary complex kept emulsions in small particle size during storage at 4°C. Data from the current study may offer useful information for designing emulsion-based delivery systems which can protect active substance against environmental stresses.
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Cannabidiol , Animales , Cinamatos , Depsidos , Emulsionantes , Emulsiones/química , Polisacáridos , Proteína de Suero de Leche/química , Ácido RosmarínicoRESUMEN
The potential activities of phthalate esters (PAEs) that interfere with the endocrine system have been focused recently. However, information on modulating the glucocorticoid receptor (GR) of PAEs is scarce. Our aim was to evaluate the agonistic / antagonistic properties of PAEs on human GR. Luciferase reporter gene assay revealed that the tested chemicals displayed no agonistic effects but dicyclohexyl phthalate (DCHP) exerted antagonistic activity in a dose-responsive manner for GR in HeLa cells. The effects of DCHP on dexamethasone (DEX)-induced GR nuclear translocation and gene expression of glucocorticoid-responsive gene expression (G6Pase, PEPCK, FAS, GILZ and MKP-1), as well as protein expression of G6Pase and PEPCK were further examined by RT-qPCR and western blot analysis. DCHP antagonized DEX-induced GR nuclear translocation and suppressed gene expression in both mRNA and protein levels. Furthermore, the results of molecular docking and molecular dynamics simulation showed that DCHP could bind to GR and exhibited potential regulation on this target protein. Collectively, we demonstrate that DCHP may act as a GR antagonist in vitro and is considered to exert endocrine effects via human GR.
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Ácidos Ftálicos , Receptores de Glucocorticoides , Disruptores Endocrinos , Glucocorticoides/antagonistas & inhibidores , Células HeLa , Humanos , Simulación de Dinámica Molecular , Ácidos Ftálicos/química , Ácidos Ftálicos/metabolismo , Receptores de Glucocorticoides/antagonistas & inhibidores , Receptores de Glucocorticoides/metabolismoRESUMEN
This study was conducted to determine the endocrine-disrupting effects of phthalate esters (PAEs) on the glucocorticoid receptor (GR) signaling. Potential (anti)glucocorticoid activities of six typical PAEs including di (2-ethylhexyl) phthalate (DEHP), diisononyl phthalate (DINP), dibutyl phthalate (DBP), diisobutyl phthalate (DIBP), diethyl phthalate (DEP) and dimethyl phthalate (DMP) were evaluated on human GR using cell viability assessment, reporter gene expression analysis, mRNA analysis, and molecular docking and simulation. For all tested chemicals, co-treatment of DEHP and DINP with dexamethasone (DEX) exhibited a synergistic effect on GR transactivity in the reporter assays. Such co-treatment also synergistically enhanced DEX-induced upregulation of GR mediated gene (PEPCK, FAS and MKP-1) mRNA expression in HepG2 cells and A549 cells. Molecular docking and dynamics simulations showed that hydrophobic interactions may stabilize the binding between molecules and GR. In summary, DEHP and DINP may be involved in synergistic effects via human GR, which highlight the potential endocrine-disrupting activities of PAEs as contaminants.
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Dexametasona/toxicidad , Disruptores Endocrinos/toxicidad , Ácidos Ftálicos/toxicidad , Receptores de Glucocorticoides/metabolismo , Células A549 , Supervivencia Celular/efectos de los fármacos , Dexametasona/administración & dosificación , Relación Dosis-Respuesta a Droga , Sinergismo Farmacológico , Disruptores Endocrinos/administración & dosificación , Genes Reporteros , Células HeLa , Células Hep G2 , Humanos , Simulación del Acoplamiento Molecular , Simulación de Dinámica Molecular , Ácidos Ftálicos/administración & dosificación , Plásmidos , Unión Proteica , Receptores de Glucocorticoides/genética , Regulación hacia ArribaRESUMEN
Human exposure to bisphenol compounds (BPs) has been implicated in the development of several chronic diseases. Instead of exploiting the traditional methods for determination of BPs, this work confirms that the human estrogen receptor α ligand binding domain (hERα-LBD) is a powerful recognition element that can be used to monitor multi-residue of BPs in urine samples by fluorescence polarization (FP) assay. Test parameters were optimized for the best performance. Under the optimal conditions, the IC50 values of BPs are in the range of 0.04-1.61 µg mL-1 . Recovery experiments were then performed to assess the accuracy and precision of the established method. The results detected by FP assay show good agreements with that of liquid chromatography-tandem mass spectrometry method with a fit of R2 = 0.9372 and 0.9640 for BPE and BPAP, respectively. A computational methodology, ligand-based pharmacophore model, was also employed to further explore the broad-specific of tested compounds. It was found that the two hydrogen bond acceptor features and one hydrophobic aliphatic feature were essential for the corresponding cross-reactivity results from the FP assay. All these results suggest that the established method can be successfully applied to monitor the occurrence of BPs in urine.
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Compuestos de Bencidrilo/orina , Receptor alfa de Estrógeno/química , Polarización de Fluorescencia/métodos , Fenoles/orina , Cromatografía Liquida , Humanos , Espectrometría de Masas/métodos , Proteínas Recombinantes de Fusión/químicaRESUMEN
The rapid analysis of stilbene estrogens is crucially important in the environment, food and health sectors, but quantitation of lower detection limit for stilbene estrogens persists as a severe challenge. We herein described a homologous and sensitive fluorescence polarization (FP) assay based on estrogen receptor α ligand binding domain (ER-LBD) to monitor stilbene estrogens in milk. Under optimal conditions, the half maximal inhibitory concentrations (IC50) of the FP assay were 9.27 nM, 12.94 nM, and 22.38 nM for hexestrol, dienestrol and diethylstilbestrol, respectively. And the corresponding limits of detection (LOD) values were 2.94 nM, 2.89 nM, and 3.12 nM. Finally, the assay was applied to determine the stilbenes in milk samples where the mean recoveries ranged from 95.76% to 112.78% and the coefficients of variation (CV) below 12.00%. Furtherly, we have focused our study on high cross-reactivity phenomena by using two in silico approaches, including molecular docking analysis and topology analysis. Overall, docking results show that several residues in the hydrophobic pocket produce hydrophobic interactions with the tested drug molecules, which contribute to the stability of their binding. In this paper, we conclude that the FP method is suitable for the rapid detection of stilbenes in milk samples, requiring no expensive analytical equipment or time-consuming sample preparation. This work offers a practical approach that applies bioscience technology in food safety testing and improves analytical speed and laboratory efficiency.
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Dietilestilbestrol/análisis , Dietilestilbestrol/química , Leche/química , Animales , Unión Competitiva , Relación Dosis-Respuesta a Droga , Receptor alfa de Estrógeno/química , Receptor alfa de Estrógeno/metabolismo , Enlace de Hidrógeno , Concentración 50 Inhibidora , Cinética , Ligandos , Modelos Moleculares , Conformación Molecular , Unión ProteicaRESUMEN
Morchella conica Pers. (M. conica) has been used both as a medical and edible mushroom and possesses antimicrobial properties and antioxidant activities. However, the antioxidant properties of polysaccharides purified from M. conica have not been studied. The aim of this study was to investigate the in vitro antioxidant properties of a polysaccharide NMCP-2 (neutral M. conica polysaccharides-2) purified from M. conica, as determined by radical scavenging assay and H2O2-induced oxidative stress in HEK 293T cells. Results showed that NMCP-2 with an average molecular weight of 48.3 kDa possessed a much stronger chelating ability on ferrous ions and a higher ability to scavenge radical scavenging 2,2-diphenyl-1-picrylhydrazyl (DPPH) than the other purified fraction of NMCP-1 from M. conica. Moreover, 3-(4, 5-Dimethylthiazol-2-yl)-2, 5-diphenyltetra-zolium bromide (MTT) assay showed that NMCP-2 dose-dependently preserved cell viability of H2O2-induced cells. The NMCP-2 pretreated group reduced the generation of reactive oxygen species (ROS) content and increased the mitochondria membrane potential (MMP) levels. In addition, Hoechst 33342 staining revealed cells treated with NMCP-2 declined nuclear condensation. Ultrastructural observation revealed that NMCP-2 pretreatment alleviated the ruptured mitochondria when exposed to H2O2. Furthermore, western blot analysis showed that NMCP-2 prevented significant downregulation of the protein expression of Bax, cleaved caspases 3, and upregulated Bcl-2 levels. These results suggest the protective effects of NMCP-2 against H2O2-induced injury in HEK 293T cells. NMCP-2 could be used as a natural antioxidant of functional foods and natural drugs.
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Agaricales/metabolismo , Antioxidantes/farmacología , Polisacáridos Fúngicos/farmacología , Peróxido de Hidrógeno/efectos adversos , Antioxidantes/aislamiento & purificación , Caspasa 3/metabolismo , Supervivencia Celular , Relación Dosis-Respuesta a Droga , Polisacáridos Fúngicos/aislamiento & purificación , Regulación de la Expresión Génica/efectos de los fármacos , Células HEK293 , Humanos , Potencial de la Membrana Mitocondrial/efectos de los fármacos , Peso Molecular , Estrés Oxidativo/efectos de los fármacos , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Proteína X Asociada a bcl-2/metabolismoRESUMEN
Star anise essential oil (SAEO) is a plant essential oil with good antibacterial activity, but its applications are limited due to its high volatility, strong smell, and unstable physical and chemical properties. The effect of selective encapsulation of SAEO by hydroxypropyl-ß-cyclodextrin (HPCD) on its compositions, volatility stability and antibacterial activity was investigated. The GC-MS results indicated that the compositions reduced and content of the compositions of SAEO changed after encapsulation. Most of the components in SAEO were successfully encapsulated by HPCD, which can be supported by data from FTIR and ¹H NMR. According to the molecular modeling results, the three guest molecules (trans-anethole, estragole and trans-foeniculin) were all docked in the cavity of HPCD on the isoallyl (or allyl) side. The volatile stability of SAEO before and after encapsulation was evaluated by electronic nose, and the results confirmed that encapsulation significantly reduced the irritating smell of SAEO and makes the clathrate have a sustained release effect. Furthermore, in the antibacterial test, the selective encapsulation of HPCD improved the inhibition effect of SAEO on Rhizopus stolonoifer, Saccharomyces cerevisiae, and E. coli and its antibacterial stability in 24 h.
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2-Hidroxipropil-beta-Ciclodextrina/química , Antibacterianos/farmacología , Illicium/química , Aceites Volátiles/farmacología , Bacterias/efectos de los fármacos , Cromatografía de Gases y Espectrometría de Masas , Pruebas de Sensibilidad Microbiana , Modelos Moleculares , Espectroscopía de Protones por Resonancia Magnética , Espectroscopía Infrarroja por Transformada de Fourier , Termodinámica , VolatilizaciónRESUMEN
Field emission (FE) uniformity and the mechanism of emitter failure of freestanding carbon nanotube (CNT) arrays have not been well studied due to the difficulty of observing and quantifying FE performance of each emitter in CNT arrays. Herein a field emission microscopy (FEM) method based on poly(methyl methacrylate) (PMMA) thin film is proposed to study the FE uniformity and CNT emitter failure of freestanding CNT arrays. FE uniformity of freestanding CNT arrays and different levels of FE current contributions from each emitter in the arrays are recorded and visualized. FEM patterns on the PMMA thin film contain the details of the CNT emitter tip shape and whether multiple CNT emitters occur at an emission site. Observation of real-time FE performance and the CNT emitter failure process in freestanding CNT arrays are successfully achieved using a microscopic camera. High emission currents through CNT emitters causes Joule heating and light emission followed by an explosion of the CNTs. The proposed approach is capable of resolving the major challenge of building the relationship between FE performance and CNT morphologies, which can significantly facilitate the study of FE non-uniformity, the emitter failure mechanism and the development of stable and reliable FE devices in practical applications.
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Measuring the conductivity changes of sensing materials to detect a wide range of radiation energy and dosage is one of the major sensing mechanisms of radiation sensors. Carbon nanotube (CNT) filled composites are suitable for sensing radiation because of the extraordinary electrical properties of CNTs and the CNT-network formed inside the polymer matrix. Although the use of CNT-based nanocomposites as potential radiation sensing materials has been widely studied, there is still a lack of theoretical models to analyze the relationship between electrical conductivity and radiation dosages. In this article, we propose a 3D model to describe the electrical conductivity of CNT-based nanocomposites when being irradiated by ionizing radiation. The Monte Carlo method has been employed to calculate radiation intensity, CNT concentration and alignment's influence on the electrical conductivity. Our simulation shows a better agreement when CNT loading is between the percolation threshold and 3% volume fraction. Radiation experiments have been performed to verify the reliability of our model to illustrate a power function relationship between the electrical conductivity of a CNT-filled polymer and radiation intensity. In addition, the predicted alignment to obtain the best sensitivity for radiation sensing has been discussed to help with CNT-network building in the fabrication process.
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Radiation shielding in space missions is critical in order to protect astronauts, spacecraft and payloads from radiation damage. Low atomic-number materials are efficient in shielding particle-radiation, but they have relatively weak material properties compared to alloys that are widely used in space applications as structural materials. However, the issues related to weight and the secondary radiation generation make alloys not suitable for space radiation shielding. Polymers, on the other hand, can be filled with different filler materials for reinforcement of material properties, while at the same time provide sufficient radiation shielding function with lower weight and less secondary radiation generation. In this study, poly(methyl-methacrylate)/multi-walled carbon nanotube (PMMA/MWCNT) nanocomposite was fabricated. The role of MWCNTs embedded in PMMA matrix, in terms of radiation shielding effectiveness, was experimentally evaluated by comparing the proton transmission properties and secondary neutron generation of the PMMA/MWCNT nanocomposite with pure PMMA and aluminum. The results showed that the addition of MWCNTs in PMMA matrix can further reduce the secondary neutron generation of the pure polymer, while no obvious change was found in the proton transmission property. On the other hand, both the pure PMMA and the nanocomposite were 18%-19% lighter in weight than aluminum for stopping the protons with the same energy and generated up to 5% fewer secondary neutrons. Furthermore, the use of MWCNTs showed enhanced thermal stability over the pure polymer, and thus the overall reinforcement effects make MWCNT an effective filler material for applications in the space industry.
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Polysaccharides from Morchella esculenta have been proven to be functional and helpful for humans. The purpose of this study was to investigate the chemical structure and anti-proliferating and antitumor activities of a Morchella esculenta polysaccharide (MEP) extracted by pulsed electric field (PEF) in submerged fermentation. The endo-polysaccharide was separated and purified by column chromatography and Gel permeation chromatography, and analyzed by gas chromatography. The MEP with an average molecular weight of 81,835 Da consisted of xylose, glucose, mannose, rhamnose and galactose at the ratio of 5.4:5.0:6.5:7.8:72.3. Structure of MEP was further analyzed by Fourier-transform infrared spectroscopy and ¹H and (13)C liquid-state nuclear magnetic resonance spectroscopy. Apoptosis tests proved that MEP could inhibit the proliferation and growth of human colon cancer HT-29 cells in a time- and dose-dependent manner within 48 h. This study provides more information on chemical structure of anti-proliferating polysaccharides isolated from Morchella esculenta.
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Antineoplásicos/química , Ascomicetos/química , Polisacáridos Fúngicos/química , Antineoplásicos/farmacología , Ascomicetos/crecimiento & desarrollo , Fraccionamiento Químico/métodos , Técnicas Electroquímicas/métodos , Fermentación , Polisacáridos Fúngicos/farmacología , Células HT29 , HumanosRESUMEN
There is a growing trend to apply field emission (FE) electron sources in vacuum electronic devices due to their fast response, high efficiency and low energy consumption compared to thermionic emission ones. Carbon nanotubes (CNTs) have been regarded as a promising class of electron field emitters since the 1990s and have promoted the development of FE technology greatly because of their high electrical and thermal conductivity, chemical stability, high aspect ratio and small size. Recent studies have shown that FE from CNTs has the potential to replace conventional thermionic emission in many areas and that it exhibits advanced features in practical applications. Consequently, FE from nanotubes and applications thereof have attracted much attention. This paper provides a comprehensive review of both recent advances in CNT field emitters and issues related to applications of CNT based FE. FE theories and principles are introduced, and the early development of field emitters is related. CNT emitter types and their FE performance are discussed. The current situation for applications based on nanotube FE is reviewed. Although challenges remain, the tremendous progress made in CNT FE over the past ten years indicates the field's development potential.
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A low density vertically aligned carbon nanotube-based field-emission cathode with a ballast resistor and coaxial gate is designed and fabricated. The ballast resistor can overcome the non-uniformity of the local field-enhancement factor at the emitter apex. The self-aligned fabrication process of the coaxial gate can avoid the effects of emitter tip misalignment and height non-uniformity.
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Morphine is a widely used opioid analgesic. However, standard morphine dosages and administration methods exhibit a short half-life and pose a risk of respiratory depression. Sustained-release microspheres can deliver prolonged efficacy and reduce side effects. We present a new controlled-release morphine gelatine microsphere (MGM) prepared using an emulsification-crosslinking strategy. The gelatine microsphere design improves the bioavailability of morphine. And it not only increases the clinical analgesic efficacy but also the safety of clinical medication through a gradual, sustained release. Besides, we describe MGMs' preparation, release, pharmacodynamics, and pharmacokinetics. And the drug metabolism pathway. We calculate the release rate of morphine by measuring plasma morphine concentration over time and pharmacokinetic parameters. It optimized the manufacturing process of MGMs, which makes the analgesic effect have a longer duration. MGMs analgesic effect shows dose dependence. After they were administrated, MGMs were released more slowly. Peak concentration was reduced, and the relative bioavailability improved. It even reached 88.84%. Its pharmacokinetic process was consistent with the two-component first-order absorption model. MGMs deliver sustained-release and long-action pharmacokinetics. It shows design goals of improving drug bioavailability, prolonging drug residence time in vivo, and maintaining stable blood drug concentration.
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Wide applications of cannabidiol (CBD) in the food and pharmaceutical industries are limited due to its low bioavailability, sensitivity to environmental pressures and low water solubility. Zein nanoparticles were stabilized by whey protein (WP) for the delivery of cannabidiol (CBD) using a modified anti-solvent approach. Particle size, surface charge, encapsulation efficiency, and re-dispersibility of nanoparticles were influenced by the zein to WP ratio. Under optimized conditions at 1:4, zein-WP nanoparticles were fabricated with CBD (200 µg/mL) and further characterized. WP absorbed on zein surface via hydrogen bond, hydrophobic forces, and electrostatic attraction. The zein-WP nanoparticles showed excellent storage stability (4 °C, dark) and effectively protected CBD degradation against heat and UV light. In vivo pharmacokinetic study demonstrated that CBD in zein-WP nanoparticles displayed 2-times and 1.75-fold enhancement in maximum concentration (C max) and the area under curve (AUC) as compared to free-form CBD. The data indicated the feasibility of developing zein-WP based nanoparticles for the encapsulation, protection, and delivery of CBD.
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In this paper, we present two methods to improve the field emission (FE) performance of vertically aligned carbon nanotube emitters that are treated with dimethyl sulfoxide (DMSO) solution and poly(3,4-ethylene dioxythiophene):polystyrene sulfonate (PEDOT:PSS) solution, respectively, and compared their performances. Both treatments force CNTs to be bundled into clusters, but the formed structures are very different. After treatment, both methods reduced the threshold electric field due to the reduction in screening effects, whereas the PEDOT:PSS treatment significantly reduced the threshold field to far lower than that of DMSO treatment. In addition, the FE efficiency and lifetime of treated CNT emitters are significantly improved. For both treated emitters, there is only slight degradation of the emission current after 80 hours of continuous FE at around 50 µA. In addition, the uniformity of both treated CNT emitters is improved which enables more CNTs to contribute to the overall current emission. This, in turn, lowers the current emitted by individual CNTs, and thereby increases the lifetime of the emitters. Therefore, this study demonstrates that these simple treatment methods of bundling CNTs into unique cluster-structures significantly improve the lifetime of FE and make them excellent candidates for large currents and long-term FE.
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This study aims to investigate the effect of pH levels (pH 7.0 and pH 8.1) on binding ability of ß-lactoglobulin (ß-LG) with lycopene (LYC) and elucidate interaction mechanisms using multi-spectroscopy and molecular docking study. ß-LG at pH 8.1 showed a stronger binding affinity to lycopene than that at pH 7.0 according to binding constant, binding number, energy transfer efficiency, and surface hydrophobicity. Lycopene bound to protein mainly by van der Waals force in the form of static quenching mode and preferred to interact with ß-LG at the top of barrel for both pH levels. Molecular dynamic simulation revealed that ß-LG/LYC complex at pH 8.1 was more stable than at pH 7.0. ß-LG/LYC complexes formed at pH 8.1 showed significantly higher ABTS radical scavenging activity than samples at pH 7.0 (p < 0.05). Data obtained may contribute valuable information for preparing a whey protein-based delivery system for lycopene.
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Lactoglobulinas/química , Licopeno/química , Simulación del Acoplamiento Molecular , Simulación de Dinámica Molecular , Análisis Espectral , Concentración de Iones de Hidrógeno , Interacciones Hidrofóbicas e Hidrofílicas , Licopeno/metabolismoRESUMEN
BACKGROUND: Although glucocorticoids (GCs) are characterized as powerful agents to treat inflammatory afflictions, they are accompanied by metabolic side effects which limit their usage. ß-Sitosterol, as a minor component found in extraction of vegetable oil, was reported to have anti-inflammatory effects in RAW 264.7 cells. OBJECTIVE: To test whether ß-sitosterol has an effect to dissociate transrepression from transactivation as a selective novel GR binder, this work evaluated the dissociated characteristics of ß-sitosterol. METHODS: The probable binding interaction between ß-sitosterol and GR was explored by molecular docking. The GR transcriptional activity of ß-sitosterol was assessed in the reporter gene assay. The ability of ß-sitosterol to modulate the transactivation and transrepression of GR was evaluated by real-time quantitative PCR analysis. RESULTS AND DISCUSSION: In the present study, ß-sitosterol treatment cannot induce GR-mediated transactivation. ß-Sitosterol exerted a potential to inhibited the expression of GR target transrepressed gene without activating the expression of GR transactivation dependent gene. Molecular docking demonstrated that ß-Sitosterol was able to bind the ligand binding domain of GR but unable to induce GR activation. CONCLUSION: This work offers evidence that ß-sitosterol may serve as a selective GR modulator.
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Simulación del Acoplamiento Molecular , Receptores de Glucocorticoides/química , Sitoesteroles/química , Animales , Células HeLa , Células Hep G2 , Humanos , Ratones , Células RAW 264.7 , Receptores de Glucocorticoides/metabolismo , Sitoesteroles/metabolismoRESUMEN
BACKGROUND: The cisterna Intrathecal Drug Delivery system (IDDS) with morphine has proven to be effective in treating refractory cancer pain above the middle thoracic vertebrae level in some countries. However, it has not been fully investigated in others. We designed the current project to investigate the efficacy and safety of cisterna IDDS for pain relief in refractory pain above the middle thoracic vertebrae level in advanced cancer patients. METHODS: This study protocol allows for eligible cancer patients to receive the cisterna IDDS operation. Pain intensity (Visual Analogue scale, VAS), quality of life (36-Item Short-Form Health Survey, SF-36), and depression (Self-Rating Depression scale, SDS) are assessed along with side effects in the postoperative follow-up visits. Recent literature suggests a potential role for cisterna IDDS morphine delivery for refractory pain states above the middle thoracic level. CONCLUSION: The results of this study may provide further evidence that cisterna IDDS of morphine can serve as an effective and safe pain relief strategy for refractory pain above the middle thoracic vertebrae level in advanced cancer patients.
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An in-depth understanding of mass transfer during brining process is important for improving the quality and characteristics of meat products. In this study, a fitted equation of time and NaCl concentrations in the aqueous phase of beef was established to calculate the NaCl diffusion coefficient for simulation. A three-dimensional simulating model of mass transfer was developed to evaluate the NaCl diffusion in beef during brining process. And the validity of this simulating model was verified by comparing the NaCl concentrations evaluated by the numerical simulation simulated with the experimental measurements. The results indicated that the power function time variant equation can predict NaCl concentrations (R2 = 0.995) and accurately calculate the NaCl diffusion coefficient (8.46 × 10-10 m2 /s). The simulating model visually showed the NaCl diffusion in beef during brining process. Therefore, this research provided a new method for predicting the NaCl diffusion in realistic meat processing. PRACTICAL APPLICATION: This research gives a new method for predicting the NaCl diffusion in meat product. The method accurately evaluated NaCl concentrations in beef at different brining time and clearly showed NaCl diffusion in beef during brining process, which could be helpful in reducing the cost and the complexity of detecting NaCl concentrations in meat during brining process.