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1.
Food Chem ; 369: 130912, 2022 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-34479008

RESUMO

In this paper, the effects of acylation modification on the gel behavior of ovalbumin (OVA) under heating induction have been investigated. From the obtained results, the acylated OVA hydrogels exhibited superior gelation properties than the native OVA hydrogels (NOVA-G) in terms of light transmission, gel hardness, resilience and water holding capacity. SEM revealed acylation modifications effectively promoted the formation of uniform and dense network structure of OVA hydrogels. The main intermolecular forces of the acylation-modified OVA hydrogels were hydrophobic interactions and hydrogen bonding. FTIR showed that acylation modifications caused 26.2% decrease in α-helix and 59.2% increase in ß-sheet content compared to NOVA-G. Furthermore, in-vitro release experiments showed that the release rate of curcumin from acylated OVA hydrogels was significantly delayed. Moreover, the above results have shown that acylation modifications can be considered as an effective method to improve the gelation as well as drug release properties of protein hydrogels.


Assuntos
Temperatura Alta , Hidrogéis , Acilação , Interações Hidrofóbicas e Hidrofílicas , Ovalbumina
2.
Food Chem ; 369: 130934, 2022 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-34488131

RESUMO

The egg yolk immunoglobulin (IgY) loaded chitosan-liposomes (IgY-CS-LP) were prepared and assisted by supercritical carbon dioxide (SCCO2). The effects of phospholipid type and SCCO2 pressure on particle size, zeta potential, encapsulation efficiency, structural properties and stabilities were investigated. The results showed that the liposomes prepared by egg yolk phosphatidylcholine (EPC) had better homogeneity and higher encapsulation rate than those by soybean phosphatidylcholine (SPC). With the increase in critical pressure, the particle size decreased dramatically and became more uniform. Under pressure of 20 MPa, it showed a preferable stability on IgY-CS-LP and superior encapsulation efficiency of IgY (76.85%). Besides, IgY could be wrapped in the phospholipid layer which has strong interaction with chitosan. The results suggested that chitosan liposome complex could form an effective carrier for IgY with method of SCCO2, which can solve the problem of IgY inactivation in vivo, so as to enhance human immunity and other effects.


Assuntos
Quitosana , Gema de Ovo , Animais , Dióxido de Carbono , Galinhas , Humanos , Imunoglobulinas , Lipossomos
3.
Food Chem ; 368: 130825, 2022 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-34496332

RESUMO

Protein-polysaccharide nanocomplexes system could improve the low stability of ACNs, making ACNs become a potential and stable pH indicator. In this study, intelligent colorimetric film was designed to monitor pork freshness by incorporating ACNs-loaded ovalbumin-propylene glycol alginate nanocomplexes (ACNs-loaded OVA-PGA) into polyvinyl alcohol/ glycerol (PG) matrix. The intelligent film (PG/ACNs-loaded OVA-PGA film) presented well barrier performance (lower water vapor permeability and light transmittance at 200-600 nm). Fourier transform infrared spectroscopy further confirmed the hydrogen bonds among film-forming components. Moreover, Scanning electron microscope and X-ray diffraction showed that ACNs-loaded OVA-PGA was uniformly distributed in film matrix but decreased the crystallinity of polyvinyl alcohol. PG/ACNs-loaded OVA-PGA film had distinguishable colorimetric response to pH 2.0-11.0 buffers and volatile ammonia. In the test, PG/ACNs-loaded OVA-PGA film displayed visible color alterations from purplish-red to dark-blue as pork freshness decreased, suggesting it can be used in intelligent packaging for real-time monitoring freshness of meat products.


Assuntos
Carne de Porco , Carne Vermelha , Alginatos , Animais , Antocianinas , Colorimetria , Embalagem de Alimentos , Concentração de Íons de Hidrogênio , Ovalbumina , Suínos
4.
Food Chem ; 372: 131215, 2022 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-34601420

RESUMO

In this paper, the effects of ultrasonic assisted glycosylation on the gel properties of ovalbumin (OVA) were studied. The molecular characteristics of native ovalbumin, heated ovalbumin, traditional glycosylated ovalbumin, ultrasonic ovalbumin and ultrasonic assisted glycosylated ovalbumin were compared. The lowest free amino group content and the highest browning intensity indicated that ultrasonic can facilitate the Maillard reaction. The gel hardness of ultrasonic glycosylation and the traditional heating glycosylation groups individually increased to 653.2 and 526.9 g compared with the control (344.9 g). The transformation of protein structure was confirmed by FTIR and fluorescence spectrum, which prompted negatively charged groups to reach the protein surface and form more disulfide bond in sOVA-X gel. The interaction between the water and the protein was strengthened, thereby increasing the water holding capacity. These results supplied a theoretical basis for the application of ultrasonic to improve protein properties.


Assuntos
Água , Glicosilação , Interações Hidrofóbicas e Hidrofílicas , Ovalbumina , Reologia
5.
Int J Biol Macromol ; 193(Pt B): 1078-1085, 2021 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-34800518

RESUMO

The antigen binding fragment (Fab) is pepsin-digested product from egg yolk immunoglobulin (IgY), which shows lower immunogenicity and higher antibacterial activity. However, it limited the application of Fab due to the spontaneous adsorption and aggregation at the air-liquid interface. The present work is to investigate the effect of surfactants polysorbate 20 (PS20), poloxamer 188 (P188), and polyethylene glycol (PEG) on the aggregation stability of Fab of IgY. The results confirmed the positive role of surfactants in improving Fab stability. PS20 could effectively prevent the generation of Fab aggregates (DLS and light-obscuration analysis). It could also distinctly increase the internal hydrophobicity level, fortify the surface charge by altering the molecular conformational characteristics of Fab. The results of CLSM and surface tension demonstrated that P188 and PEG were co-adsorbed with Fab at the air-liquid interface and inhibited the formation of aggregation. PS20 competitively adsorbed in the gap between Fab molecules to inhibit the formation of aggregates. These findings would give an in-depth understanding of protein aggregation behavior influenced by surfactants and provide a theoretical basis for the development of functional food based on Fab active fragments.

6.
J Agric Food Chem ; 69(31): 8747-8757, 2021 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-34337939

RESUMO

High-purity Fab fragment and immunoglobulin Y (IgY) were prepared to evaluate their anti-inflammatory activity in the lipopolysaccharide (LPS)-induced Raw 264.7 macrophage system. Compared with IgY, the Fab fragment possessed a greater potency in inhibiting the inflammation by nitric oxide (NO)/inducible nitric oxide synthase (iNOS) and prostaglandin-E2 (PGE2)/cyclooxygenase-2 (COX-2) pathways. The Fab fragment attenuated the levels of tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), and interleukin-10 (IL-10) to 38.07 ± 1.86-48.39 ± 11.33 pg/mL (63.1-71.0% inhibition), 31.59 ± 3.91-38.08 ± 4.44 pg/mL (72.4-77.1% inhibition), and 20.62 ± 0.46-21.91 ± 0.65 pg/mL (50-53% inhibition), respectively. Additionally, the Fab fragment significantly inhibited the translocation of nuclear transcription factor-κB (NF-κB) p65 and the phosphorylation of mitogen-activated protein kinase (MAPK) proteins, including ERK1/2 (41.5/33.2%), JNK1/2 (44.2/39.6%), and p38 (42.2%). The Fab fragment could be internalized into cells, and the pretreatment of RAW 264.7 macrophages with the Fab fragment reduced the mRNA expression of the Toll-like receptor (TLR4, 32.7-44.4% inhibition) and αVß3 integrin (76.1% inhibition). In conclusion, Fab fragments regulated the TLR4 and αVß3 integrin-mediated inflammatory processes by blocking the NF-κB and MAPKs pathways in the LPS-induced RAW 264.7 macrophage system.


Assuntos
Fragmentos Fab das Imunoglobulinas/imunologia , NF-kappa B , Receptor 4 Toll-Like , Animais , Ciclo-Oxigenase 2/metabolismo , Imunoglobulinas , Integrina alfa5 , Integrinas , Lipopolissacarídeos , Macrófagos/metabolismo , Camundongos , Proteínas Quinases Ativadas por Mitógeno/genética , NF-kappa B/genética , NF-kappa B/metabolismo , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase Tipo II/metabolismo , Células RAW 264.7 , Receptor 4 Toll-Like/genética , Receptor 4 Toll-Like/metabolismo
7.
Food Chem ; 355: 129635, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-33780798

RESUMO

In this study, we evaluated potential usage of acylated ovalbumin (AOVA) nanogels fabricated via acylation modification and heat-induced self-assembly process as novel delivery systems for curcumin. Compared to native ovalbumin (NOVA) nanogels without chemical acylation, the obtained AOVA nanogels have shown smaller average hydrodynamic diameter (155.73 nm), relatively uniform size distribution (polydispersity index around 0.28), enhanced negative surface charge (-24.3 mV), and an improved stability under the conditions of high ionic strength, different pH and storage time. Moreover, AOVA nanogels exhibited a remarkable conformational change in secondary and tertiary structures, improved surface hydrophobicity, and increased free sulfhydryl content compared with NOVA nanogels. Moreover, curcumin encapsulated in AOVA nanogels displayed higher encapsulation efficiency (93.64%) and slower sustained release under simulated gastrointestinal conditions as compared with NOVA nanogels. Hence, we have suggested that AOVA nanogels successfully fabricated with improved physicochemical properties as a novel ideal carrier for hydrophobic active compounds.


Assuntos
Curcumina/química , Portadores de Fármacos/química , Nanogéis/química , Ovalbumina/química , Acilação , Estabilidade de Medicamentos , Temperatura Alta , Concentração de Íons de Hidrogênio , Interações Hidrofóbicas e Hidrofílicas
8.
Carbohydr Polym ; 242: 116387, 2020 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-32564851

RESUMO

Chitosan-based macroparticle is a common carrier for enzyme immobilization applied in food industry. Driven by the requirement of large carrier pores for the biomacromolecular substrates such as protein, the eggshell membrane powder (ESMP) was employed as multifunctional porogen to improve the physicochemical structure of chitosan-based macroparticles. The prepared macroparticles were characterized by SEM, XRD, FTIR, Raman spectroscopy, nitrogen adsorption-desorption isotherms, and thermogravimetric analysis. The results showed that an increase of ESMP percentage could improve the porosity of macro holes in macroparticles, and it also enlarged the size of mesopores. Moreover, the ESMP significantly increased (P < 0.05) the amount of papain immobilization, whereas the specific activity of immobilized papain achieved a maximum value of 871.95 U/mg at CSESM2 and then declined with the increase of ESMP. Therefore, the inclusion of 20 % ESMP in chitosan-based macroparticles gave the highest activity of its immobilized protease.


Assuntos
Quitosana/química , Casca de Ovo/química , Peptídeo Hidrolases/química , Animais , Físico-Química , Quitosana/metabolismo , Casca de Ovo/metabolismo , Enzimas Imobilizadas/química , Enzimas Imobilizadas/metabolismo , Estrutura Molecular , Tamanho da Partícula , Peptídeo Hidrolases/metabolismo , Porosidade , Propriedades de Superfície
9.
Artigo em Inglês | MEDLINE | ID: mdl-32062365

RESUMO

Antigen-binding (Fab) and crystallizable (Fc) fragments are the active components of yolk immunoglobulin (IgY), which have been widely used in the pharmaceutical field. However, the common purification methods for the Fab and Fc fragments use combinations of multi-columns are complex and time-consuming. The objective of this study was to improve the separation efficiency of the Fab and Fc fragments from the hydrolyzed IgY and increase the purity of the isolated Fab and Fc fragments. Natural IgY was hydrolyzed using papain for 6 hr and then treated with 45% saturated ammonium sulfate to remove small molecular-weight-peptides. The fraction containing Fab and Fc fragments was loaded on a DEAE-Sepharose ion exchange column and the Fab fraction was washed out first with 10 mM Tris-HCl buffer (pH 7.6). Then, the Fc fraction bound to the DEAE Sepharose was eluted with 10 mM Tris-HCl buffer (pH 7.6) containing 0.21 M NaCl. The purity of the two fragments was 88.7% and 90.1%, respectively. The results of Western blotting and MS analyses indicated that this method purified Fab and Fc fractions with high purity. This method is easy and simple compared with other methods, and the active fragments separated can be easily used.


Assuntos
Fragmentos Fab das Imunoglobulinas/análise , Fragmentos Fab das Imunoglobulinas/isolamento & purificação , Fragmentos Fc das Imunoglobulinas/análise , Fragmentos Fc das Imunoglobulinas/isolamento & purificação , Imunoglobulinas/metabolismo , Sulfato de Amônio/química , Animais , Western Blotting , Galinhas , Cromatografia por Troca Iônica , Fragmentos Fab das Imunoglobulinas/química , Fragmentos Fab das Imunoglobulinas/metabolismo , Fragmentos Fc das Imunoglobulinas/química , Fragmentos Fc das Imunoglobulinas/metabolismo , Imunoglobulinas/química , Papaína/metabolismo
10.
Food Chem ; 317: 126349, 2020 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-32078990

RESUMO

The effect of supercritical carbon dioxide (SCCD) treatment at varying processing time (30-90 min) on foaming and structure properties of egg white protein (EWP) were studied in this paper. The highest foaming ability (107.7%) was obtained after 60 min SCCD treatment, which was 3.6-fold to the control group. Foaming stability kept stable under the processing time of 75 min. Results of surface tension, surface hydrophobicity, rheological properties and particle size indicated that protein was easier to spread to the gas-liquid interface and generate molecular rearrangement. Circular dichroism (CD) and Endogenous fluorescence spectrum showed that there were slight changes on the secondary structure of EWP. The α-helical structure of the protein was destroyed and the particle size became uneven, which indicated that the protein structure became more flexible and loose. The results of this study indicate that SCCD treatment had a potential to be implemented to enhance foaming properties of EWP.


Assuntos
Dióxido de Carbono/química , Cromatografia com Fluido Supercrítico/métodos , Proteínas do Ovo/química , Interações Hidrofóbicas e Hidrofílicas , Tamanho da Partícula , Conformação Proteica em alfa-Hélice , Conformação Proteica em Folha beta , Reologia , Tensão Superficial
11.
Ultrason Sonochem ; 60: 104767, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31539731

RESUMO

The effects of high-intensity ultrasonic (HIU) treatment on the functional properties of egg yolk were studied in the present work. After HIU treatment, the emulsifying, foaming and gel properties of the egg yolk solution significantly increased, but the foam stability decreased. SDS-PAGE results showed that there was no obvious change in the protein bands of egg yolk, indicating that the yolk proteins did not undergo covalent crosslinking or degradation. HIU treatment enhanced the zeta potential of egg yolk components in solution and increased the free sulfhydryl content of egg yolk proteins. Moreover, the particle size distribution of egg yolk components in solution changed markedly, and these changes demonstrated that HIU treatment caused the aggregation of yolk low-density lipoprotein and the partial dissociation of yolk granules. These results revealed that HIU treatment could change the aggregation of yolk components, which in turn could influence the solution characteristics of egg yolk, finally resulting in changes to the functional properties of egg yolk.


Assuntos
Gema de Ovo/fisiologia , Ondas Ultrassônicas , Animais , Galinhas , Gema de Ovo/química , Gema de Ovo/ultraestrutura , Interações Hidrofóbicas e Hidrofílicas , Lipoproteínas LDL/análise , Microscopia Eletrônica de Varredura , Tamanho da Partícula
12.
J Hazard Mater ; 388: 121728, 2020 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-31784124

RESUMO

The solvated mercuric ion (Hg2+) from industrial pollutants are highly toxic to the ecological environment and human health. Driven by urgent need for the selective and sensitive detection of Hg2+, a magnetic relaxation switching (MRS) based on Fe3O4 nanoparticles (NPs) was designed. Practically, the concentrations of Hg2+ in industrial pollutant is usually much higher than the detection range. Thus, gold nanoparticles (AuNPs) were synthesized on the surface of Fe3O4 NPs to enable the visual detection of Au@Fe3O4 NPs. The presence of Hg2+ in sample can specifically cause the aggregation of Au@Fe3O4-aptamers NPs through T-Hg2+-T base pairs, leading to the change in transverse relaxation time T2 value of detection solution. The MRS sensor showed excellent response for Hg2+ ions in the range of 10 nM-100 nM and 100 nM to 5 µM. A highly sensitive and selective measurement of Hg2+ was obtained with a limit of detection of 2.7 nM. Noticeably, the visual detection can qualitatively analyze the Hg2+ beyond 5 µM by naked eye without advanced instrumentation and skilled operators.

13.
Mikrochim Acta ; 186(12): 770, 2019 11 12.
Artigo em Inglês | MEDLINE | ID: mdl-31713685

RESUMO

Titanium carbide quantum dots functionalized with ε-poly-L-lysine (PLL) were synthesized by sonication cutting and hydrothermal synthesis. The deprotonated Ti3C2 MXene quantum dots (Ti3C2 MQDs) exhibit excitation wavelength-dependent blue photoluminescence with typical excitation/emission peaks at 330/415 nm and a quantum yield of 22% due to strong quantum confinement. The fluorescence of ε-poly-L-lysine protected Ti3C2 MQDs (PLL-protected Ti3C2 MQDs) is reduced via an inner filter effect after the addition of cytochrome c (cyt-c). Response to cyt-c is linear in the 0.2 to 40 µM concentration range and the detection limit is 20.5 nM. In the presence of trypsin, cyt-c is hydrolyzed to small peptides, and the Fe3+ ion in cyt-c probably is reduced to Fe2+ with the aid of the digestive enzyme. This results in the restoration of the blue fluorescence of the modified MQDs. Fluorescence increases linearly in the 0.5 to 80 µg mL-1 trypsin concentration range with the detection limit of 0.1 µg mL-1. The method was successfully applied to the determination of cyt-c and trypsin in spiked serum samples. Graphical abstractSchematic of a method for the fluorometric "turn-off-on" determination of cytochrome c and trypsin based on ε-poly-L-lysine (PLL) protect MXene quantum dots (Ti3C2 MQDs).


Assuntos
Citocromos c/análise , Fluorometria , Polilisina/química , Pontos Quânticos/química , Titânio/química , Tripsina/análise , Citocromos c/metabolismo , Corantes Fluorescentes/química , Tamanho da Partícula , Teoria Quântica , Propriedades de Superfície , Tripsina/metabolismo
14.
Ultrason Sonochem ; 58: 104644, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31450374

RESUMO

This study was to evaluate the effect of ultrasound-assisted glycation with xylose on the foaming properties, physicochemical and structural characteristics of ovalbumin (OVA). The number of free amino groups in the glycated OVA (sOVA-X) significantly decreased with the increase of treatment time. The results obtained by circular dichroism (CD) and spectrofluorimetric measurements showed that there were slight changes on the subunits and secondary structure of OVA, indicating that the tertiary structure became more flexible and loose after the sonicated glycation treatment. The glycated OVA had higher solubility and foaming properties than the untreated samples. Therefore, ultrasound improved the glycation extent, and the changes in molecular structure were responsible for their different foaming ability and foaming stability. Our study also provided principle knowledge to understand how the viscosity and rheology were related to the foaming properties of OVA glycation by xylose. The results indicated that ultrasound-assisted glycation could be an excellent approach to improve the functional properties of OVA and promote its application in food industry.


Assuntos
Ovalbumina/química , Reologia , Ondas Ultrassônicas , Xilose/química , Glicosilação , Interações Hidrofóbicas e Hidrofílicas , Cinética , Reação de Maillard , Estrutura Secundária de Proteína , Estrutura Terciária de Proteína , Viscosidade
15.
Colloids Surf B Biointerfaces ; 183: 110449, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31465939

RESUMO

To develop a promising antibacterial agent for wound-care dressing, a series of silver nanoparticles (AgNPs) and eggshell membrane (ESM) composites (AgNPs/ESM) were prepared. AgNPs were prepared using a chemical reduction method and their characteristics were determined. Various pH and processing time combinations were tested to find the optimal conditions for preparing AgNPs/ESM composites. To obtain the optimal nontoxic-level silver release, the AgNPs stock solution was diluted to 2 times, 4 times, 6 times, 8 times and 10 times with water and the concentration of silver released by the composites was also tested. All the prepared composites showed antibacterial activity, but the activity was the strongest when the stock AgNPs solution was diluted to four times (a concentration of silver was 2.41 mg/L). The addition of AgNPs changed the ESM from hydrophobic to hydrophilic by lowering the water contact angles from 105° to 75°, which is important for the wound-healing process. And the AgNPs/ESM composites had a higher surface area (159.08 m2/g) than the natural ESM (24.32 m2/g) and a suitable pore size (10.92 nm) as well, endowing with better absorption and antibacterial abilities. These findings suggested that the AgNPs/ESM composites are promising candidates for the development of antimicrobial agent for biomedical devices and therapeutic applications, such as wound-healing agent.


Assuntos
Antibacterianos/química , Casca de Ovo/química , Nanopartículas Metálicas/química , Prata/química , Adsorção , Animais , Antibacterianos/farmacologia , Bandagens , Escherichia coli/efeitos dos fármacos , Concentração de Íons de Hidrogênio , Nanopartículas Metálicas/ultraestrutura , Testes de Sensibilidade Microbiana , Microscopia Eletrônica de Varredura , Cicatrização/efeitos dos fármacos
16.
J Biomed Nanotechnol ; 15(6): 1232-1240, 2019 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-31072431

RESUMO

One-pot green synthesis of highly fluorescent carbon dots (CDs) was developed by hydrothermal treatments of ovalbumin (OVA) from hen eggs. The hydrothermal treatment time, temperature, OVA concentration and pH value as the effective factors on the light emissions of the CDs were optimized. The optical and structural characteristics of the CDs were confirmed with UV, FL, FTIR, Raman, XPS, XRD, HRTEM and AFM. The quantum yield was up to 34.5%, and the CDs were small in size (2.51 nm) with an excellent water solubility. The CDs also exhibited excellent pH and salt stability, suggesting that they can be used under harsh environmental conditions. The MTT assay of mouse osteoblast and macrophage cells line showed CDs had extremely low cytotoxicity. In addition, the in vitro imaging study revealed the CDs had an excellent optical property as well as biocompatibility and thus could be used as a superior fluorescent bioimaging agent. In conclusion, a highly photoluminescent CDs with high solubility, excellent pH and salt stability and low cytotoxicity were synthesized with OVA as a natural precursor. The photoluminescent CDs showed an excellent optical property as well as biocompatibility and thus have a great potential for biomedical applications in the future.


Assuntos
Pontos Quânticos , Animais , Carbono , Sobrevivência Celular , Galinhas , Feminino , Corantes Fluorescentes , Camundongos , Ovalbumina
17.
Anal Chem ; 91(10): 6769-6774, 2019 05 21.
Artigo em Inglês | MEDLINE | ID: mdl-31050405

RESUMO

The main issues of imaging ellipsometry-based biosensing for small molecules are the low sensitivity and narrow detection range due to the low molecular weight of small molecules that results in a negligible signal. To meet this challenge, we theoretically investigated the deciding factors of the ellipsometry signal and further applied the theory to guide the design of ellipsometry-based biosensor using metal nanoparticles that have a high dielectric constant. Significant signal amplification effects can be achieved by using nanoparticle labels including magnetic nanoparticles and gold nanoparticles. Guided by the theory, we have developed a sensitive surface-enhanced imaging ellipsometry (SEIE)-biosensor for detecting chloramphenicol in real milk sample with high sensitivity (with a limit of detection of 6 pg/mL) and broaden detection range. This nanoparticles-enabled SEIE not only greatly improves the sensitivity of conventional imaging ellipsometry-based biosensors but also retains the advantages of conventional methods in terms of automated and convenient operation, providing an effective strategy for detection of trace small molecules in complex samples that holds great promise in scientific research, clinical diagnosis, and food safety.


Assuntos
Antibacterianos/análise , Técnicas Biossensoriais/métodos , Cloranfenicol/análise , Contaminação de Alimentos/análise , Nanopartículas/química , Óptica e Fotônica/métodos , Animais , Antibacterianos/imunologia , Anticorpos Monoclonais/imunologia , Cloranfenicol/imunologia , Limite de Detecção , Leite/química
18.
Poult Sci ; 98(10): 4401-4407, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31041437

RESUMO

Preserved egg, a traditional Chinese egg product, is regarded as an anti-inflammatory food in traditional Chinese medicine. This study was aimed to examine anti-inflammatory effect of the simulated gastrointestinal digestive products of whole preserved egg (DWPE), preserved egg white (DPEW), and preserved egg yolk (DPEY) on lipopolysaccharide (LPS)-stimulated RAW264.7 cells. The results demonstrated that DWPE, DPEW, or DPEY inhibited the LPS-induced secretion of Nitric oxide (NO), without marked cytotoxicity. The DWPE, DPEW, and DPEY significantly suppressed the secretion of pro-inflammatory cytokines, such as tumor necrosis factor (TNF)-α and interleukin (IL)-6. Particularly, the inhibition rate of DPEW on NO, IL-6, and TNF-α could reach 25 to 27%, 31 to 42%, and 26 to 38%, respectively (P < 0.05). Furthermore, the DPEW and DPEY downregulated the gene expression of Cyclooxygenase-2 and inducible nitric oxide synthase in a dose-dependent manner. Taken together, this study indicated that DWPE, DPEW, and DPEY, especially DPEW, might serve as functional food for anti-inflammatory therapy.


Assuntos
Anti-Inflamatórios/farmacologia , Clara de Ovo/química , Gema de Ovo/química , Inflamação/tratamento farmacológico , Óvulo/efeitos dos fármacos , Animais , Anti-Inflamatórios/administração & dosagem , Ovos/análise , Medicina Tradicional Chinesa , Camundongos , Células RAW 264.7
19.
Carbohydr Polym ; 215: 348-357, 2019 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-30981364

RESUMO

In this study, genipin and glutaraldehyde in varied concentrations were utilized in chitosan crosslinking under alkaline condition. A UV/Vis analysis was used to investigate the molecular structure of genipin and glutaraldehyde in an aqueous alkaline solution. The results showed the formation of glutaraldehyde dimer and polymerized genipin. The FTIR-ATR, SEM, DSC, XRD, mechanical properties, crosslinking degree and swelling ratio of chitosan based films crosslinked by genipin and glutaraldehyde were determined. The results indicated that the hydrogen bonds formed between genipin and chitosan enabled the films crosslinked by genipin (1 and 5 mmol/L) to have a higher degree of crosslinking, but a lower swelling ratio than glutaraldehyde (1 and 5 mmol/L). Genipin enabled the chitosan-based film to possess better mechanical properties and crystallinity than glutaraldehyde. The polymerization of genipin had a substantial effect on the network structure and swelling behavior of chitosan-based films crosslinked by genipin.

20.
Int J Biol Macromol ; 131: 293-300, 2019 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-30876897

RESUMO

Improvement of emulsifying properties by phosphorylation could have a wide potential application in food industry. In this study, ovalbumin (OVA) was phosphorylated under wet-heating in the presence of sodium tripolyphosphate. Phosphorylated OVA (P-OVA) with low, middle, high phosphorus content were obtained with reaction time increased. Their enhanced emulsification capacity and the mechanism were investigated. Compared with native OVA (N-OVA), the emulsifying activity and stability of P-OVA were increased by 26% and 109% (P < 0.05), respectively. The structure studies (Fourier transform infrared spectroscopy, circular dichroism spectra, scanning electron microscope) demonstrated that introduction of phosphate groups to OVA increased the molecular flexibility of P-OVA. The absolute values of surface zeta-potential and surface hydrophobicity were increased as the phosphorus content increased, which indicated that the phosphate group inhibited protein aggregation. And it caused a large amount absorption of protein on the surface of the oil droplets, which ultimately improved the emulsion stability. Both particle size and microscopic results of emulsion showed that the particle size of OVA reduced as the degree of phosphorylation increased, which improved the emulsifying ability.


Assuntos
Emulsificantes/química , Emulsões/química , Ovalbumina/química , Interações Hidrofóbicas e Hidrofílicas , Ovalbumina/ultraestrutura , Tamanho da Partícula , Fosforilação , Estabilidade Proteica , Análise Espectral
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