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1.
Int J Biol Macromol ; 266(Pt 1): 131160, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38547946

RESUMO

In present study, bilayer emulsions with different interfacial structures stabilized by casein/butyrylated dextrin nanoparticles (CDNP), chitosan (CS) and chitosan nanoparticles (CSNP) were prepared to overcome the limitations of conventional emulsions. The effects of chitosan morphology and incorporation sequences on the bilayer emulsions were examined. Bilayer emulsions prepared with CDNP as the inner layer and CS/CSNP as the outer layer were observed to have smaller droplet sizes (1.39 ± 86.74 um and 1.45 ± 7.87 um). Bilayer emulsions prepared with CDNP as the inner layer and CS as the outer layer exhibited the lowest creaming index (2.38 %) after 14 days of storage, indicating excellent stability. Furthermore, bilayer emulsion prepared with CDNP as the inner layer and CS as the outer layer also exhibited a uniform water distribution, excellent protein oxidative stability, and uniformly distributed droplets by the measurement of Low-field NMR, intrinsic tryptophan fluorescence and laser confocal laser scanning microscopy. These results indicated that the study provided a theoretical basis for the development and design of bilayer emulsions with different interfacial structures. This study also provides a new material for the preparation of delivery systems that protect biologically active compounds. Bilayer emulsions are promising for applications in traditional and manufactured food products.


Assuntos
Caseínas , Quitosana , Dextrinas , Emulsões , Nanopartículas , Quitosana/química , Caseínas/química , Emulsões/química , Nanopartículas/química , Dextrinas/química , Tamanho da Partícula
2.
Int J Mol Sci ; 25(3)2024 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-38339154

RESUMO

Increasingly globally prevalent obesity and related metabolic disorders have underscored the demand for safe and natural therapeutic approaches, given the limitations of weight loss drugs and surgeries. This study compared the phytochemical composition and antioxidant activity of five different varieties of citrus physiological premature fruit drop (CPFD). Untargeted metabolomics was employed to identify variations in metabolites among different CPFDs, and their antilipidemic effects in vitro were assessed. The results showed that Citrus aurantium L. 'Daidai' physiological premature fruit drop (DDPD) and Citrus aurantium 'Changshan-huyou' physiological premature fruit drop (HYPD) exhibited higher levels of phytochemicals and stronger antioxidant activity. There were 97 differential metabolites identified in DDPD and HYPD, including phenylpropanoids, flavonoids, alkaloids, organic acids, terpenes, and lipids. Additionally, DDPD and HYPD demonstrated potential antilipidemic effects against oleic acid (OA)-induced steatosis in HepG2 hepatocytes and 3T3-L1 adipocytes. In conclusion, our findings reveal the outstanding antioxidant activity and antilipidemic effects of CPFD, indicating its potential use as a natural antioxidant and health supplement and promoting the high-value utilization of this resource.


Assuntos
Antioxidantes , Citrus , Fenilenodiaminas , Antioxidantes/metabolismo , Citrus/metabolismo , Frutas/química , Flavonoides/farmacologia , Extratos Vegetais/química
3.
Food Microbiol ; 119: 104459, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38225037

RESUMO

Lemon essential oil (LEO) is a common natural antibacterial substance, and encapsulating LEO into nanoemulsions (NEs) can improve their stability and broaden its application. Our study aimed to investigate the bacterial inhibitory effect of LEO-NEs against Escherichia coli (E. coli). Results showed that the minimum inhibitory concentration (MIC) of LEO-NEs was 6.25 mg/mL, and the time-kill curve showed that E. coli were significantly killed by LEO-NEs after 5 h of treatment at 1MIC. Flow-cytometry analysis showed that LEO-NEs adversely affected the cell-membrane depolarisation, cell-membrane integrity, and efflux pump function of E. coli. Confocal laser scanning microscopy demonstrated that 8MIC of LEO-NEs induced changes in the cell-membrane permeability and cell-wall integrity of E. coli. Proteomic results suggested that the mode of action LEO-NEs against E. coli was to enhance bacterial chemotaxis and significantly inhibit ribosomal assembly. They may also affect butyric acid, ascorbic acid and aldehyde metabolism, and sulphur-relay system pathways. In conclusion, LEO-NEs had potential application as a natural antibacterial agent for the control of E. coli in the food industry.


Assuntos
Escherichia coli , Óleos Voláteis , Proteômica , Antibacterianos/farmacologia , Óleos Voláteis/farmacologia , Membrana Celular , Bactérias
4.
Micromachines (Basel) ; 15(1)2024 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-38258240

RESUMO

Operational amplifiers (op-amps) are widely used in circuit systems. The increasing complexity of the power supply network has led to the susceptibility of the power supply port to electromagnetic interference (EMI) in circuit systems. Therefore, it is necessary to investigate the electromagnetic susceptibility (EMS) of op-amps at the power supply port. In this paper, we assessed the effect of EMI on the operational performance of op-amps through the power supply port by a bulk current injection (BCI) method. Firstly, we conducted the continuous sine wave into the power supply port by a current injection probe and measured the change in the offset voltage under EMI. Secondly, we proposed a new method of conducted susceptibility and obtained the susceptibility threshold regularities of the op-amps at the power supply port under the interference of different waveform signals. Our study provided conclusive evidence that EMI reduced the reliability of the op-amp by affecting the offset voltage of op-amps and demonstrated that the sensitivity type of op-amps was peak-sensitive at the power supply port. This study contributed to a deep understanding of the EMS mechanism and guided the design of electromagnetic compatibility (EMC) of op-amps.

5.
Food Chem ; 404(Pt A): 134590, 2023 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-36444015

RESUMO

The pea protein isolate nanoparticles/octenyl succinic anhydride linear dextrin (PPINs/OSA-LD) composite particles were fabricated by heating at acidic condition. Heating treatment not only made OSA-LD dissolve, but also promoted the hydrophobic interactions between PPINs and OSA-LD. With the increase of OSA-LD content, the average diameter of composite particles decreased due to the avoidance of hydrophobic aggregation between PPINs during heating, and the composite particles became more compact and regular. The high internal phase emulsions (HIPEs) stabilized by composite particles exhibited smaller droplet size, higher viscosity and modulus attributing to the formation of denser interfacial layer. The results of low field nuclear magnetic resonance proved that the HIPEs stabilized by composite particles showed more uniform distribution of water and oil. This work provided a facile method to fabricate composite particles, which had excellent capacity to stabilize the HIPEs.


Assuntos
Nanopartículas , Proteínas de Ervilha , Emulsões , Dextrinas , Calefação
6.
J Agric Food Chem ; 70(30): 9421-9431, 2022 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-35862634

RESUMO

High-fat diet (HFD) is closely related to the formation of metabolic diseases. Studies have confirmed that neohesperidin dihydrochalcone (NHDC) possesses the biological activity of preventing glycolipid metabolism disorder. To explore the mechanism of its preventive activity against glucolipid metabolism disorder, HFD-treated rats were orally administered with NHDC for 12 weeks continuously. The results showed that, compared with the HFD group, the intervention of 40-80 mg/kg body weight of NHDC effectively downregulated the level of fasting blood glucose. Western blot analysis revealed that the treatment of NHDC alleviated the inhibitory effect of HFD on the expression of hepatic GLUT-4 and IRS-1. Further studies confirmed that NHDC reduced the degree of HFD-stimulated inflammation of ileum through the TLR4/MyD88/NF-κB signaling pathway. Moreover, ileum intestinal flora analysis showed that intragastric administration of NHDC reversed the change of Proteobacteria abundance and the Firmicutes/Bacteroidetes (F/B) ratio caused by HFD. At the generic level, NHDC promoted the relative abundance of Coprococcus, Bifidobacterium, Clostridium, Oscillospira, and [Eubacterium], while reducing the relative abundance of Defluviitalea and Prevotella. Taken together, these findings suggest that NHDC possesses the biological activity of improving HFD-induced glycolipid metabolism disorder.


Assuntos
Hesperidina , Doenças Metabólicas , Animais , Chalconas , Dieta Hiperlipídica/efeitos adversos , Glicolipídeos , Hesperidina/análogos & derivados , Hesperidina/farmacologia , Camundongos , Camundongos Endogâmicos C57BL , Ratos
7.
Int J Biol Macromol ; 214: 220-229, 2022 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-35714865

RESUMO

Silver nanoparticles (AgNPs) were widely used in the antibacterial field because of their excellent antibacterial properties. In this study, we used hesperidin and pectin as reductants and stabilizers, and prepared uniform and stable Hesperidin-Pectin AgNPs (HP-AgNPs) by a simple microwave-assisted process. Increasing the proportion of hesperidin, P-AgNPs, HP-AgNPs1, HP-AgNPs2 and H-AgNPs were obtained respectively. With the increase of hesperidin ratio, the mean particle size and zeta potential increased gradually. Fourier transform infrared spectroscopy (FTIR) analysis showed that Ag+ was reduced by hesperidin and pectin. Antibacterial tests showed that HP-AgNPs2 showed the MIC values of 66.7 µg/mL against E. coli. In addition, HP-AgNPs2 was selected to clarify its antibacterial mechanism against E. coli. Morphological experiments showed that HP-AgNPs2 stress caused damage to the cell wall of E. coli, as well as leakage of its contents and an increase in reactive oxygen species (ROS). On the other hand, the release of Ag+ during cell co-culture was studied and the results showed that most of the Ag+ released was taken up by E. coli. The synergistic effect of hesperidin and pectin resulted in a significant enhancement of the antibacterial properties of AgNPs. These preliminary data suggest that HP-AgNPs has good antibacterial activity and may be developed as an effective antibacterial nanomaterial.


Assuntos
Hesperidina , Nanopartículas Metálicas , Antibacterianos/química , Escherichia coli , Hesperidina/farmacologia , Nanopartículas Metálicas/química , Testes de Sensibilidade Microbiana , Pectinas/farmacologia , Prata/química , Espectroscopia de Infravermelho com Transformada de Fourier
8.
Sensors (Basel) ; 22(4)2022 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-35214283

RESUMO

Process variations during manufacturing lead to differences in the performance of the chips. In order to better utilize the performance of the chips, it is necessary to perform maximum operation frequency (Fmax) tests to place the chips into different speed bins. For most Fmax tests, significant efforts are put in place to reduce test cost and improve binning accuracy; e.g., our conference paper published in ICICM 2017 presents a novel binning sensor for low-cost and accurate speed binning. However, by promoting chips placed at the lower bins, because of conservative binning, into higher bins, the overall profit can greatly increase. Therefore, this paper, extended based on a conference paper, presents a novel and adaptive methodology for speed binning, in which the paths impacting the speed bin of a specific IC are identified and adapted by our proposed on-chip Binning Checker and Binning Adaptor. As a result, some parts at a bin margin can be promoted to higher bins. The proposed methodology can be used to optimize the Fmax yield of a digital circuit when it has redundant timing in clock tree, and it can be integrated into current Fmax tests with low extra cost. The proposed adaptive system has been implemented and validated on five benchmarks from ITC, ISCAS89, and OpenSPARCT2 core on 28 nm Altera FPGAs. Measurement results show that the number of higher bin chips is improved by 7-16%, and our cost analysis shows that the profit increase is between 1.18% and 3.04%.


Assuntos
Algoritmos , Software
9.
Molecules ; 26(15)2021 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-34361632

RESUMO

The present study focuses on the biological synthesis, characterization, and antibacterial activities of silver nanoparticles (AgNPs) using extracellular extracts of Aspergillus japonicus PJ01.The optimal conditions of the synthesis process were: 10 mL of extracellular extracts, 1 mL of AgNO3 (0.8 mol/L), 4 mL of NaOH solution (1.5 mol/L), 30 °C, and a reaction time of 1 min. The characterizations of AgNPs were tested by UV-visible spectrophotometry, zeta potential, scanning electron microscope (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), and thermogravimetric (TG) analyses. Fourier transform infrared spectroscopy (FTIR) analysis showed that Ag+ was reduced by the extracellular extracts, which consisted chiefly of soluble proteins and reducing sugars. In this work, AgNO3 concentration played an important role in the physicochemical properties and antibacterial properties of AgNPs. Under the AgNO3 concentration of 0.2 and 0.8 mol/L, the diameters of AgNPs were 3.8 ± 1.1 and 9.1 ± 2.9 nm, respectively. In addition, smaller-sized AgNPs showed higher antimicrobial properties, and the minimum inhibitory concentration (MIC) values against both E. coli and S. aureus were 0.32 mg/mL.


Assuntos
Antibacterianos , Aspergillus/metabolismo , Química Verde/métodos , Nanopartículas Metálicas/química , Prata/química , Antibacterianos/química , Antibacterianos/farmacologia
10.
Bioprocess Biosyst Eng ; 43(11): 2017-2026, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32572568

RESUMO

Herein, we reported a green biosynthesis method of copper nanoparticles (CuNPs) at microwave irradiation condition by using pectin as a stabilizer and ascorbic acid as a reducing agent. Under the optimum conditions, CuNPs1 and 2 were synthesized under microwave times 0 and 3 min, respectively. Transmission electron microscope and scanning electron microscope (SEM) tests showed that CuNPs1 and 2 had irregular polygon particles with average diameters of 61.9 ± 19.4 and 40.9 ± 13.6 nm, respectively. Zeta potentials of CuNPs1 and 2 were -45.2 and -48.7 mV, respectively. X-ray diffraction, Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), and X-ray photoelectron spectroscopy techniques were used to characterize the properties of CuNPs. Furthermore, inhibition zone tests showed that CuNPs2 exhibited higher antimicrobial activities against Escherichia coli, Staphylococcus aureus, and Aspergillus japonicus than CuNPs1. The antibacterial activities were also studied by the bacterial growth kinetics in broth media, and CuNPs2 exhibited lower minimum bactericidal concentrations than CuNPs1.


Assuntos
Anti-Infecciosos/síntese química , Cobre/química , Nanopartículas Metálicas/química , Testes de Sensibilidade Microbiana , Pectinas/química , Antibacterianos/farmacologia , Ácido Ascórbico , Aspergillus/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Química Verde , Cinética , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Tamanho da Partícula , Espectroscopia Fotoeletrônica , Espectroscopia de Infravermelho com Transformada de Fourier , Staphylococcus aureus/efeitos dos fármacos , Termogravimetria , Difração de Raios X
11.
Sensors (Basel) ; 19(9)2019 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-31035501

RESUMO

This paper presents a novel tangential electric-field sensor with an embedded integrated balun for sensing up a tangential electric field over a circuit surface in the near-field measurements covering the GPS band. The integrated balun is embedded into the sensor to transform the differential voltage induced by the electric dipole into the single output voltage. The measurement system with a high mechanical resolution for the characterizations and tests of the sensor is detailed in this paper. The frequency response of the sensor characterized by a microstrip line from 1.35 GHz to 1.85 GHz (covering the GPS band) is rather flat. The rejection to the magnetic field of the sensor is up to 20.1 dB. The applications and validations of the sensor are conducted through passive/active circuit measurements.

12.
Food Chem ; 286: 1-7, 2019 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-30827581

RESUMO

Surfactant and microwave assisted extraction (S-MAE) was used for pectin extraction from orange peel. First, we optimized the conditions of microwave assisted extraction (MAE), e.g., irradiation time, liquid-to-solid ratio (LSR), and pH on pectin yield (PY), galacturonic acid (GA) content, and degree of esterification (DE) using a Box-Behnken design. Under optimal conditions (pH 1.2, 7.0 min, and 21.5 v/w LSR), we obtained a PY of 28.0 ±â€¯0.5%, which was close to the predicted value (31.1%). Second, we analyzed the effect of surfactant on microwave extraction of pectin. Among the surfactants investigated, Tween-80 (8 g/L, w/v) increased PY by 17.0%. Compared with conventional solvent extraction, S-MAE is a novel and efficient method for pectin extraction, which generated a higher (p < 0.05) PY (32.8%), GA content (78.1%), DE (69.8%), and Mw (286.3 kDa).


Assuntos
Citrus sinensis/metabolismo , Micro-Ondas , Pectinas/química , Tensoativos/química , Cromatografia Líquida de Alta Pressão , Esterificação , Ácidos Hexurônicos/química , Concentração de Íons de Hidrogênio , Pectinas/isolamento & purificação , Espectroscopia de Infravermelho com Transformada de Fourier
13.
Food Chem ; 218: 231-236, 2017 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-27719903

RESUMO

Near-infrared spectroscopy (NIR) was used for qualitative and quantitative detection of honey adulterated with high-fructose corn syrup (HFCS) or maltose syrup (MS). Competitive adaptive reweighted sampling (CARS) was employed to select key variables. Partial least squares linear discriminant analysis (PLS-LDA) was adopted to classify the adulterated honey samples. The CARS-PLS-LDA models showed an accuracy of 86.3% (honey vs. adulterated honey with HFCS) and 96.1% (honey vs. adulterated honey with MS), respectively. PLS regression (PLSR) was used to predict the extent of adulteration in the honeys. The results showed that NIR combined with PLSR could not be used to quantify adulteration with HFCS, but could be used to quantify adulteration with MS: coefficient (Rp2) and root mean square of prediction (RMSEP) were 0.901 and 4.041 for MS-adulterated samples from different floral origins, and 0.981 and 1.786 for MS-adulterated samples from the same floral origin (Brassica spp.), respectively.


Assuntos
Contaminação de Alimentos/análise , Xarope de Milho Rico em Frutose/análise , Mel/análise , Maltose/análise , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Análise Discriminante , Xarope de Milho Rico em Frutose/química , Análise dos Mínimos Quadrados , Modelos Lineares , Maltose/química
14.
J Food Sci ; 77(4): C374-80, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22429109

RESUMO

Total of 4 pattern recognition methods for the authentication of pure camellia oil applying near infrared (NIR) spectroscopy were evaluated in this study. Total of 115 samples were collected and their authenticities were confirmed by gas chromatography (GC) in according to China Natl. Standard (GB). A preliminary study of NIR spectral data was analyzed by unsupervised methods including principal component analysis (PCA) and hierarchical cluster analysis (HCA). Total of 2 supervised classification techniques based on discriminant analysis (DA) and radical basis function neural network (RBFNN) were utilized to build calibration model and predict unknown samples. In the wavenumber range of 6000 to 5750 cm⁻¹, correct classification rate of both supervised and unsupervised solutions all can reach 98.3% when smoothing, first derivative, and autoscaling were used. The good performance showed that NIR spectroscopy with multivariate calibration models could be successfully used as a rapid, simple, and nondestructive method to discriminate pure camellia oil.


Assuntos
Camellia/química , Inspeção de Alimentos/métodos , Óleos de Plantas/química , Sementes/química , Calibragem , China , Análise por Conglomerados , Análise Discriminante , Ácidos Graxos/análise , Ionização de Chama , Modelos Químicos , Redes Neurais de Computação , Reconhecimento Automatizado de Padrão , Óleos de Plantas/normas , Análise de Componente Principal , Espectroscopia de Luz Próxima ao Infravermelho
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