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Ultrasonics Sonochemistry Dec 2023Ovalbumin (OVA), characterized by its high concentration in eggs, possesses remarkable foaming properties. Nevertheless, OVA is highly sensitive to thermal changes and...
Improvement of foaming properties of ovalbumin: Insights into the synergistic effect of preheating and high-intensity ultrasound on physicochemical properties and structure analysis.
Ovalbumin (OVA), characterized by its high concentration in eggs, possesses remarkable foaming properties. Nevertheless, OVA is highly sensitive to thermal changes and acid-base conditions, substantially hampering its application potential for foaming purposes within the food industry. This experiment aimed to examine the effects of preheating and high-intensity ultrasound (HIU) treatment at different powers on OVA foaming properties and explore the underlying mechanisms. The results revealed that OVA exhibited the highest foaming capacity (31.5 %) and foaming stability (96.7 %) under the treatment condition of 200w + 60°C. Additionally, significant improvements were observed in the content of free sulfhydryl groups (37.27 μmg/g), solution viscosity (142.33 mPa·s), and surface hydrophobicity (37.27 μg BPB) under this condition. The absolute value of the zeta potential (-10.28 mV) was significantly increased in the 200w + 60°C treatment group. Moreover, the polymer dispersity index of OVA (0.6045) was significantly reduced, resulting in improved dispersion than the control group. The structural analysis revealed significant changes in the α-helix and β-sheet content of OVA after treatment at 200w + 60 °C. The X-ray diffraction pattern exhibited sharper peaks, indicating a crystal structure, and the fluorescence peak displayed a slight blue shift along with increased hydrophobicity. Moreover, the preheating and HIU treatment induced a continuous uneven and irregular pore structure in OVA, which ultimately enhanced its foaming properties. In conclusion, the preheating and HIU treatment offers a novel approach to enhance the foaming properties of OVA.
Topics: Ovalbumin; Hydrophobic and Hydrophilic Interactions; Viscosity
PubMed: 37925915
DOI: 10.1016/j.ultsonch.2023.106672 -
Environmental Health Perspectives Jun 2023Exposure to environmental pollutants, including benzo[a]pyrene (BaP), has been implicated in allergic diseases and intestinal microbiota homeostasis, but the...
BACKGROUND
Exposure to environmental pollutants, including benzo[a]pyrene (BaP), has been implicated in allergic diseases and intestinal microbiota homeostasis, but the environment-microbiota-immunity triangular relationship and to what extent BaP-induced remodeling of the gut microbiota contributes to intestinal allergic inflammation remain to be established.
OBJECTIVES
We investigated the impact of BaP on intestinal allergic inflammation and examined the relationship between this effect and gut microbiota dysbiosis. We explored the potential ability of intestinal bacteria to degrade BaP and alleviate cytotoxicity as a detoxification strategy to counteract the effects of BaP exposure.
METHODS
We combined microbiome shotgun metagenomics with animal histological and intestinal allergic inflammatory responses to assess the effects of BaP () in a 23-d toxicity test in antigen-induced allergic female mice. In addition, genome annotation, quantitative analysis of BaP, and cytotoxicity-tests using CaCo-2 cells were conducted to infer the role of intestinal bacteria in BaP detoxification.
RESULTS
BaP exposure impacted the taxonomic composition and the functional potential of the gut microbiota and aggravated antigen-induced intestinal allergic inflammatory responses. The level of inflammatory cytokines correlated with the abundance of specific bacterial taxa, including 28-4 and . We identified 614 bacteria harboring genes implicated in the degradation of BaP, and 4 of these bacterial strains were shown to significantly reduce the cytotoxicity of BaP to CaCo-2 cells .
DISCUSSION
Using allergic female mice as a model, we investigated the relationship between BaP, microbiota, and host immune reactions, highlighting the role of gut bacteria in BaP-aggravated allergic reactions. Our findings offer novel insight toward establishing the causal relationship between BaP exposure and the occurrence of allergic disorders. Identifying gut bacteria that degrade BaP may provide new strategies for ameliorating BaP cytotoxicity. https://doi.org/10.1289/EHP11874.
Topics: Humans; Female; Animals; Mice; Gastrointestinal Microbiome; Ovalbumin; Caco-2 Cells; Hypersensitivity; Inflammation; Bacteria
PubMed: 37267060
DOI: 10.1289/EHP11874 -
Journal of Visualized Experiments : JoVE Oct 2014Allergic responses are the result of the activation of mast cells and basophils, and the subsequent release of vasoactive and proinflammatory mediators. Exposure to an...
Allergic responses are the result of the activation of mast cells and basophils, and the subsequent release of vasoactive and proinflammatory mediators. Exposure to an allergen in a sensitized individual can result in clinical symptoms that vary from minor erythema to life threatening anaphylaxis. In the laboratory, various animal models have been developed to understand the mechanisms driving allergic responses. Herein, we describe a detailed method for measuring changes in vascular permeability to quantify localized allergic responses. The local anaphylaxis assay was first reported in the 1920s, and has been adapted from the technique published by Kojima et al. in 2007(1). In this assay, mice sensitized to OVA are challenged in the left ear with vehicle and in the right ear with OVA. This is followed by an intravenous injection of Evans Blue dye. Ten min after injecting Evans Blue, the animal is euthanized and the dye that has extravasated into the ears is extracted overnight in formamide. The absorbance of the extracted dye is then quantified with a spectrophotometer. This method reliably results in a visual and quantifiable manifestation of a local allergic response.
Topics: Anaphylaxis; Animals; Capillary Permeability; Evans Blue; Histamine Release; Immunoglobulin E; Mast Cells; Mice; Mice, Inbred BALB C; Ovalbumin
PubMed: 25350839
DOI: 10.3791/52005 -
International Journal of Nanomedicine 2020Nanocarriers could deliver significantly higher amounts of antigen to antigen-presenting cells (APCs), which have great potential to stimulate humoral and cellular...
BACKGROUND
Nanocarriers could deliver significantly higher amounts of antigen to antigen-presenting cells (APCs), which have great potential to stimulate humoral and cellular response in cancer immunotherapy. Thereafter, silica solid nanosphere (SiO) was prepared, and a model antigen (ovalbumin, OVA) was covalently conjugated on the surface of SiO to form nanovaccine (OVA@SiO). And the application of OVA@SiO for cancer immunotherapy was evaluated.
MATERIALS AND METHODS
SiO solid nanosphere was prepared by the Stöber method, then successively aminated by aminopropyltriethoxysilane and activated with glutaraldehyde. OVA was covalently conjugated on the surface of activated SiO to obtain nanovaccine (OVA@SiO). Dynamic light scattering, scanning electron microscope, and transmission electron microscope were conducted to identify the size distribution, zeta potential and morphology of OVA@SiO. The OVA loading capacity was investigated by varying glutaraldehyde concentration. The biocompatibility of OVA@SiO to DC2.4 and RAW246.7 cells was evaluated by a Cell Counting Kit-8 assay. The uptake of OVA@SiO by DC2.4 and its internalization pathway were evaluated in the absence or presence of different inhibitors. The activation and maturation of bone marrow-derived DC cells by OVA@SiO were also investigated. Finally, the in vivo transport of OVA@SiO and its toxicity to organs were appraised.
RESULTS
All results indicated the successful covalent conjugation of OVA on the surface of SiO. The as-prepared OVA@SiO possessed high antigen loading capacity, which had good biocompatibility to APCs and major organs. Besides, OVA@SiO facilitated antigen uptake by DC2.4 cells and its cytosolic release. Noteworthily, OVA@SiO significantly promoted the maturation of dendritic cells and up-regulation of cytokine secretion by co-administration of adjuvant CpG-ODN.
CONCLUSION
The as-prepared SiO shows promising potential for use as an antigen delivery carrier.
Topics: Adjuvants, Immunologic; Animals; Antigen Presentation; Antigens; Cancer Vaccines; Dendritic Cells; Drug Carriers; Female; Immunotherapy; Mice; Mice, Inbred C57BL; Nanospheres; Oligodeoxyribonucleotides; Ovalbumin; RAW 264.7 Cells; Silicon Dioxide
PubMed: 32368049
DOI: 10.2147/IJN.S242463 -
Protein Science : a Publication of the... Apr 1995Most serpins are inhibitors of serine proteinases and are thought to undergo a conformational change upon complex formation with proteinase that involves partial... (Comparative Study)
Comparative Study
Most serpins are inhibitors of serine proteinases and are thought to undergo a conformational change upon complex formation with proteinase that involves partial insertion of the reactive center loop into a beta-sheet of the inhibitor. Ovalbumin, although a serpin, is not an inhibitor of serine proteinases. It has been proposed that this deficiency arises from the presence of a charged residue, arginine, at a critical point (P14) in the reactive center region, which prevents loop insertion into the beta-sheet and thereby precludes inhibitory properties. To test whether loop insertion is prevented in ovalbumin we have examined the properties of two forms of ovalbumin: the native protein and S-ovalbumin, a form that forms spontaneously from native ovalbumin and has increased stability. Calorimetric measurements showed that S-ovalbumin was more stable than ovalbumin by about 3 kcal mol-1. CD spectra, which indicated that S-ovalbumin had less alpha-helix than native ovalbumin, and 1H NMR spectra, which indicated very similar overall structures, suggest limited conformational differences between the two forms. From comparison of the susceptibility of the reactive center region of each protein to proteolysis by porcine pancreatic elastase and by subtilisin Carlsberg, we concluded that the limited native-to-S conformational change specifically affected the reactive center region. These data are consistent with a structure for S-ovalbumin in which part of the reactive center loop has inserted into beta-sheet A to give a more stable structure, analogously to other serpins. However, the rate of loop insertion appears to be very much lower than for inhibitory serpins.(ABSTRACT TRUNCATED AT 250 WORDS)
Topics: Alkaline Phosphatase; Calorimetry; Circular Dichroism; Crystallography, X-Ray; Guanidine; Guanidines; Hydrogen-Ion Concentration; Magnetic Resonance Spectroscopy; Ovalbumin; Pancreatic Elastase; Protein Conformation; Protein Structure, Secondary; Protein Structure, Tertiary; Serpins; Subtilisins; Thermodynamics
PubMed: 7613461
DOI: 10.1002/pro.5560040403 -
Frontiers in Immunology 2021CpG-oligodeoxynucleotides (CpG-ODNs) constitute an attractive alternative for asthma treatment. However, very little evidence is available from studies on the oral...
CpG-oligodeoxynucleotides (CpG-ODNs) constitute an attractive alternative for asthma treatment. However, very little evidence is available from studies on the oral administration of CpG-ODNs in animals. Previously, we developed acid-resistant particles (named ODNcap) as an oral delivery device for ODNs. Here, we showed that free feeding of an ODNcap-containing feed prophylactically attenuates allergic airway inflammation, hyperresponsiveness, and goblet cell hyperplasia in an ovalbumin-induced asthma model. Using transcriptomics-driven approaches, we demonstrated that injury of pulmonary vein cardiomyocytes accompanies allergen inhalation challenge, but is inhibited by ODNcap feeding. We also showed the participation of an airway antimicrobial peptide (Reg3γ) and fecal microbiota in the ODNcap-mediated effects. Collectively, our findings suggest that daily oral ingestion of ODNcap may provide preventive effects on allergic bronchopulmonary insults regulation of mechanisms involved in the gut-lung connection.
Topics: Administration, Oral; Animals; Antimicrobial Peptides; Bronchial Hyperreactivity; Female; Gastrointestinal Microbiome; Hypersensitivity; Mice; Mice, Inbred BALB C; Oligodeoxyribonucleotides; Ovalbumin; Pancreatitis-Associated Proteins; Pneumonia
PubMed: 34867960
DOI: 10.3389/fimmu.2021.738041 -
PloS One 2019The skin is a very suitable organ for the induction of immune responses to vaccine antigens. Antigen delivery systems to the skin by needle and syringe directly deposit...
The skin is a very suitable organ for the induction of immune responses to vaccine antigens. Antigen delivery systems to the skin by needle and syringe directly deposit the antigen into the epidermal-dermal compartment, one of the most immunocompetent sites due to the presence of professional antigen-presenting cells aimed at the induction of antigen-specific T cells. In this study, we analyzed the amount of ovalbumin as an antigen delivered to the skin by a microneedle. When ovalbumin protein as an antigen was delivered to the skin of mice using a dissolving microneedle, it induced an immune response through the enhanced proliferation and cytokines production by the splenocytes and lymph nodes. Also, it effectively increased the ovalbumin-specific CD8+ T cell and CD4+ T cell population and induced an ovalbumin-specific CTL response against the graft of ovalbumin-expressing EG7 tumor cells in the immunized mice. Also, we identified the inhibition of tumor growth and prevention of tumor formation in the context of the therapeutic and prophylactic vaccine, respectively through EG-7 tumor mouse model. Finally, these data show the potential of patches as attractive antigen delivery vehicles.
Topics: Administration, Cutaneous; Animals; Antigens; CD4-Positive T-Lymphocytes; CD8-Positive T-Lymphocytes; Cell Proliferation; Drug Delivery Systems; Immunity; Immunotherapy; Mice; Needles; Neoplasms; Ovalbumin; T-Lymphocytes, Cytotoxic; Transdermal Patch; Treatment Outcome
PubMed: 31386690
DOI: 10.1371/journal.pone.0220382 -
International Journal of Biological... Sep 2017The interactions of tetracycline (TC), oxytetracycline (OTC) and chlortetracycline (CTC) with ovalbumin (OVA), the main allergen protein of egg white, were investigated...
The interactions of tetracycline (TC), oxytetracycline (OTC) and chlortetracycline (CTC) with ovalbumin (OVA), the main allergen protein of egg white, were investigated by molecular spectroscopy and electrophoresis at three pH conditions (1.5, 4.6 and 7.4). Molecular and synchronous fluorescence, UV-vis spectroscopy, electrophoresis and H NMR were used to study the interaction process. Tetracyclines interact with ovalbumin fluorescence by a static quenching mechanism with non-fluorescent complex formation changing the native protein structure. The binding constant (K) ranged from 2.11×10 to 58.4×10Lmol, and corresponding thermodynamic parameters were measured at different temperatures and pH values. The binding process was spontaneous (ΔG<0), and the magnitude of the interaction increased in the following order: TC
Topics: Allergens; Animals; Egg White; Electrophoresis; Ovalbumin; Protein Binding; Spectrum Analysis; Tetracyclines
PubMed: 28428126
DOI: 10.1016/j.ijbiomac.2017.04.052 -
Poultry Science Apr 2000The eggshell matrix is mainly composed of proteins that are thought to influence shell formation and calcification and, thus, modify the resulting properties of the... (Comparative Study)
Comparative Study
The eggshell matrix is mainly composed of proteins that are thought to influence shell formation and calcification and, thus, modify the resulting properties of the shell. We investigated the potential of some of these proteins as biomarkers of eggshell quality by developing a competitive indirect ELISA for quantifying ovotransferrin, ovalbumin, and ovocleidin-17 in eggshell extract. Eggshell fragments were demineralized in acetic acid (20%) and freeze-dried. The micro-extraction yield was markedly increased (>50%) when Tween 20 was added to the subsequent extraction and dialysis milieus. Microplates were coated with ovotransferrin and ovalbumin in a 0.1M carbonate-bicarbonate buffer, but ovocleidin-17 was fixed with acetone (-20 C, 20 min). Optimal dilutions of the monoclonal (ovotransferrin) and polyclonal (ovalbumin and ovocleidin-17) antibodies were 1/3,000, 1/25,000 and 1/4,000, respectively. The inhibition curves were optimized by preincubating the antibodies and proteins overnight. The intraassay coefficient (<5%), parallelism of the standards and samples curves, and recovery (101%) were satisfactory for ovotransferrin. Measurements of ovalbumin were less precise because of higher interassay variation and differences between the slopes of standard and sample inhibition curves. Ovocleidin-17 assays showed similar slopes for standard and eggshell extracts. Although the total protein in soluble matrix extracts was not affected by age, the concentrations of these proteins were higher in eggshell extracts from older hens compared with those from young hens: 1.98x for ovotransferrin, 1.86x for ovalbumin, and 1.58x for ovocleidin-17. The quantification of specific eggshell matrix proteins in shell of differing quality is, therefore, a promising tool for analyzing the origin of eggshell faults and may provide useful information for breeding programs.
Topics: Aging; Animals; Chickens; Conalbumin; Egg Proteins; Egg Shell; Electrophoresis, Polyacrylamide Gel; Enzyme-Linked Immunosorbent Assay; Female; Ovalbumin
PubMed: 10780658
DOI: 10.1093/ps/79.4.580 -
Poultry Science Mar 2019In addition to small amounts of minerals and carbohydrates, most of the dry matter of chicken egg white is protein, making egg white an ideal resource for obtaining food...
In addition to small amounts of minerals and carbohydrates, most of the dry matter of chicken egg white is protein, making egg white an ideal resource for obtaining food proteins. Ovalbumin (OVA), which accounts for more than 50% of the total egg white protein, is one of the most widely studied food proteins due to its multiple functional properties, and it has also been used as a model protein molecule in many research fields. The objective of this study was to develop a simple and rapid method for the purification of OVA from egg whites on large scale. First, OVA was separated from ovomucin, ovotransferrin, and ovomucoid by polyethylene glycol (PEG) concentration, using the following optimal parameters: the PEG concentration was 15%, the pH was 6.5, the salt concentration was 100 mmol/L, and the operating temperature was 10°C. The OVA-rich supernatant obtained from PEG precipitation was further purified by isoelectric precipitation at a pI of 4.5 and a temperature of 4°C, and the purified OVA was obtained with at a purity of 95.1% by HPLC, with a yield of 46.4%. After the extraction of OVA, the PEG solution was vacuum dried and then utilized cyclically in the PEG precipitation steps. The whole purification process could be finished within 2 to 3 h at a scale of several kilograms of egg white. This method has the advantages of rapidity, simplicity, low cost, and ease of scalability.
Topics: Animals; Chemical Precipitation; Chickens; Egg White; Ovalbumin; Polyethylene Glycols
PubMed: 30184130
DOI: 10.3382/ps/pey402