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Journal of Applied Glycoscience 2020Ovomucin, a hen egg white protein, is characterized by its hydrogel-forming properties, high molecular weight, and extensive -glycosylation with a high degree of...
Ovomucin, a hen egg white protein, is characterized by its hydrogel-forming properties, high molecular weight, and extensive -glycosylation with a high degree of sialylation. As a commonly used food ingredient, we explored whether ovomucin has an effect on the gut microbiota. Glycan analysis revealed that ovomucin contained core-1 and 2 structures with heavy modification by -acetylneuraminic acid and/or sulfate groups. Of the two mucin-degrading gut microbes we tested, grew in medium containing ovomucin as a sole carbon source during a 24 h culture period, whereas did not. Both gut microbes, however, degraded ovomucin -glycans and released monosaccharides into the culture supernatants in a species-dependent manner, as revealed by semi-quantified mass spectrometric analysis and anion exchange chromatography analysis. Our data suggest that ovomucin potentially affects the gut microbiota through -glycan decomposition by gut microbes and degradant sugar sharing within the community.
PubMed: 34354526
DOI: 10.5458/jag.jag.JAG-2019_0020 -
Journal of Food Science and Technology Mar 2019The demand for duck meat and eggs in Asian countries increases every year. Duck egg albumen has become an important ingredient in the food industry alongside its hen... (Review)
Review
The demand for duck meat and eggs in Asian countries increases every year. Duck egg albumen has become an important ingredient in the food industry alongside its hen counterpart, because of its excellent nutritive and functional properties. The major proteins in duck albumen are ovalbumin, ovomucoid, ovomucin, conalbumin, and lysozyme. Comparing with hen albumen, lower contents of ovalbumin, conalbumin, lysozyme and ovoflavoprotein are found in duck albumen. Nevertheless, duck albumen shows better gelling and foaming properties than hen albumen. During storage, duck albumen gel properties are enhanced, while foam volume and foam stability are decreased. Moreover, the changes in quality indices of duck egg including the thinning of the albumen, an increase in albumen pH, loss of water and carbon dioxide occur as storage time is increased. Some processes such as alkaline treatment also cause the loss in nutritive value of egg albumen. In this review, the composition and functional properties of duck albumen and how they are affected by processing conditions are also addressed, in comparison with hen albumen. A better understanding of duck egg albumen would be beneficial so that the food processing industry can exploit the potential of this avian protein.
PubMed: 30956290
DOI: 10.1007/s13197-019-03669-x -
Jornal de Pediatria 2024Evaluate biomarkers capable of safely guiding Yellow fever vaccine (YFV) vaccination among individuals suspicious of hen's egg allergy, and identify factors associated...
OBJECTIVE
Evaluate biomarkers capable of safely guiding Yellow fever vaccine (YFV) vaccination among individuals suspicious of hen's egg allergy, and identify factors associated with a higher risk for adverse events after immunization (AEAI).
METHODS
Patients underwent skin prick test (SPT) for standardized allergens: whole egg, egg white, egg yolk; YFV (1:10 dilution; Biomanguinhos-Fiocruz), and intradermal test (IDT; YFV 0.02 mL, 1:100 dilution) and positive and negative controls. Serum levels of specific IgE (sIgE) for a whole egg, egg white, egg yolk, egg albumin, ovomucoid, lysozyme, and conalbumin (ImmunoCap®; ThermoFisher®) were obtained. Patients sensitized to YFV were submitted to YFV desensitization, and those negatives received YFV (0.5mL) and remained under surveillance for at least one hour.
RESULTS
103 patients were enrolled, 95% under 12 years old. 71% (81/103) of patients had reactions: 80% immediate, 11% mixed, and 9% delayed. There was an association between positive skin test results with YFV and the severity of the reaction (OR:7.64; 95%CI:1.61-36.32; p = 0,011). Only the presence of sIgE to ovomucoid was associated with clinical symptoms (p = 0,025). Thirty patients underwent the YFV desensitization protocol.
CONCLUSION
There is a relationship between the positivity of the egg's components and the severity of the clinical reaction. Furthermore, the relationship between the positivity of the tests with the YFV and egg's components may show a tendency to look at ovomucoid and conalbumin, but it is not a certainty. Therefore, further studies are needed to confirm these associations, and for now, the authors still recommend using the vaccine for testing when necessary.
Topics: Humans; Animals; Female; Child; Egg Hypersensitivity; Ovomucin; Yellow Fever; Conalbumin; Chickens; Immunoglobulin E; Vaccination; Allergens
PubMed: 37597532
DOI: 10.1016/j.jped.2023.07.004 -
Poultry Science May 2024Chicken egg chalaza (CLZ) is a natural colloidal structure in eggs that exists as an egg yolk stabilizer and is similar in composition to egg white. In this study, the...
Chicken egg chalaza (CLZ) is a natural colloidal structure in eggs that exists as an egg yolk stabilizer and is similar in composition to egg white. In this study, the proteome, phosphoproteome, and N-glycoproteome of CLZ were characterized in depth. We hydrolyzed the CLZ proteins and enriched the phosphopeptides and glycopeptides. We identified 45 phosphoproteins and 80 N-glycoproteins, containing 59 phosphosites and 203 N-glycosylation sites, respectively. Typically, the ovalbumin in CLZ was both phosphorylated and N-glycosylated, with 4 phosphosites and 4 N-glycosylation sites. Moreover, we identified 2 N-glycosylated subunits of ovomucin, mucin-5B and mucin-6, with 32 and nine N- glycosylation sites, respectively. Analysis of the phosphorylation and N-glycosylation status of CLZ proteins could provide novel insights into the structural and functional characteristics of CLZ.
Topics: Animals; Chickens; Egg Proteins; Proteomics; Proteome; Avian Proteins; Glycoproteins; Glycosylation; Ovum; Phosphoproteins
PubMed: 38518664
DOI: 10.1016/j.psj.2024.103629 -
The Biochemical Journal Mar 1990Ovomucin participates in the ovomucin-gel-forming properties because of its shape and its ability to interact in a specific spatial organization. Purified from chicken...
Ovomucin participates in the ovomucin-gel-forming properties because of its shape and its ability to interact in a specific spatial organization. Purified from chicken egg-white by exclusion chromatography with Sephacryl S-300 and Sepharose CL-2B and analysed by light-scattering, it exhibited an Mr of about 40 x 10(6). This large Mr can be explained by the aggregation of polymers that can be degraded into 3 x 10(6)-Mr fragments by reduction with dithiothreitol. The values for hydrodynamic parameters such as Mr, radius of gyration, hydrodynamic radius, mass per unit length and combinations of them suggested that ovomucin is a linear and highly flexible molecule conferring upon it a random-coil-like structure in 0.2 M-NaCl solution. Analysis of the ovomucin molecules by electron microscopy revealed its linear character but also indicated a lower Mr than that obtained in the light-scattering experiments. By temperature-induced non-specific aggregation of an ovomucin solution containing other globular egg proteins, an attempt was made to find out what conditions are required for gel formation and to examine the quality of aggregation that is obtained under these conditions. Results show that the viscosity of the solution did not increase after heat treatment. Apparently, in the ovomucin gel, specific spatial organization of the ovomucin molecules is required for hydrogel formation.
Topics: Animals; Chickens; Egg Proteins; Electrophoresis, Agar Gel; Molecular Weight; Ovomucin; Viscosity
PubMed: 2327958
DOI: 10.1042/bj2660697 -
The Biochemical Journal Apr 19751. New preparations of reduced carboxymethylated beta-ovomucin (S-carboxymethyl-beta-ovomucin) were homogeneous by sedimentation analysis, analytical sedimentation to...
1. New preparations of reduced carboxymethylated beta-ovomucin (S-carboxymethyl-beta-ovomucin) were homogeneous by sedimentation analysis, analytical sedimentation to equilibrium in CsCl gradients, and disc electrophoresis in sodium dodecyl sulphate. 2. Degradation of S-carboxymethyl-beta-ovomucin with either CNBr or trypsin indicated the presence of a subunit (approx. mol. wt. 112300). 3. Electron microscopy showed that S-carboxymethyl-beta-ovomucin consisted of chains of globular units (approx. mol. wt. 103 000). IN 6M-guanidinium chloride S-carboxymethyl-beta-ovomucin existed mainly as an aggregate (mol. wt. 720 000). 4. S-Carboxymethyl-beta-ovomucin contained ester sulphate (4.24%, W/W) and carbohydrate (60%, W/W), which consisted of large amounts of galactose (22%, W/W), galactosamine (8.9%, W/W) and sialic acid (10.6%, W/W). 5. An unreduced soluble fibrous component (component SGH) extracted from crude ovomucin precipitate with 5M-guanidinium chloride contained beta-ovomucin (approx. 70%, W/W). By using the Scheraga-Mandelkern equation the molecular weight of component SGH was calculated to be 11.5 times 10(6).
Topics: Amino Acids; Animals; Carbohydrates; Carboxylic Acids; Centrifugation; Chickens; Cyanogen Bromide; Egg Proteins; Electrophoresis, Disc; Esters; Galactosamine; Galactose; Microscopy, Electron; Molecular Weight; Ovalbumin; Ovomucin; Oxidation-Reduction; Sialic Acids; Trypsin; Viscosity
PubMed: 1171686
DOI: 10.1042/bj1470055 -
Foods (Basel, Switzerland) Dec 2023To compare the physical and chemical changes in egg whites during storage, assisting in the evaluation of differences in egg freshness between various chicken breeds, we...
To compare the physical and chemical changes in egg whites during storage, assisting in the evaluation of differences in egg freshness between various chicken breeds, we chose 240 blue-shelled eggs (Blue group) and 240 commercial brown-shelled eggs (Brown group) that 28-week-old hens had laid. In this study, all eggs were stored at 25 °C. The egg weight, egg components' weight and proportion, Haugh Unit value and the contents of S-ovalbumin, ovomucin and lysozyme in the thick albumen (KA) and thin albumen (NA) were measured at eight time points every 3 days until the 21st day of storage. The eggshell, yolk and KA proportions in the Brown group were significantly lower, whereas the NA proportion was significantly higher than that in the Blue group ( < 0.001). The Haugh Unit value and S-ovalbumin in the Brown group were significantly higher, whereas KA ovomucin and NA lysozyme were significantly lower than those in the Blue group ( < 0.001). There existed significant negative correlations between the KA and NA, irrespective of weight or proportion. The Haugh Unit value was significantly positively correlated with lysozyme and ovomucin, but significantly negatively correlated with S-ovalbumin. During storage, the KA weight (proportion), Haugh Unit value, lysozyme and ovomucin decreased, whereas the NA weight (proportion) and S-ovalbumin increased. At each time point, the NA lysozyme in the Brown group was lower than that in the Blue group ( < 0.05). After storage for 6 days, the KA ovomucin in the Brown group began to be lower than that in the Blue group ( < 0.05). The study showed that the weight (proportion) differences in egg components between blue-shelled eggs and commercial brown-shelled eggs are mainly due to the NA. The Haugh Unit value and albumin protein indexes of blue-shelled eggs were better than those of brown-shelled eggs, and showed mild changes during storage, indicating the better storage performance of blue-shelled eggs.
PubMed: 38137245
DOI: 10.3390/foods12244441 -
The Journal of Biological Chemistry Dec 1949
Topics: Eggs; Humans; Ovomucin
PubMed: 15393769
DOI: No ID Found -
JAMA Network Open Jul 2023Egg introduction in infants at age 4 to 6 months is associated with a lower risk of immunoglobulin E-mediated egg allergy (EA). However, whether their risk of EA at age... (Randomized Controlled Trial)
Randomized Controlled Trial
IMPORTANCE
Egg introduction in infants at age 4 to 6 months is associated with a lower risk of immunoglobulin E-mediated egg allergy (EA). However, whether their risk of EA at age 12 months is affected by maternal intake of eggs at birth is unknown.
OBJECTIVE
To determine the effect of maternal egg intake during the early neonatal period (0-5 days) on the development of EA in breastfed infants at age 12 months.
DESIGN, SETTING, AND PARTICIPANTS
This multicenter, single-blind (outcome data evaluators), randomized clinical trial was conducted from December 18, 2017, to May 31, 2021, at 10 medical facilities in Japan. Newborns with at least 1 of 2 parents having an allergic disease were included. Neonates whose mothers had EA or were unable to consume breast milk after the age of 2 days were excluded. Data were analyzed on an intention-to-treat basis.
INTERVENTIONS
Newborns were randomized (1:1) to a maternal egg consumption (MEC) group, wherein the mothers consumed 1 whole egg per day during the first 5 days of the neonate's life, and a maternal egg elimination (MEE) group, wherein the mothers eliminated eggs from their diet during the same period.
MAIN OUTCOMES AND MEASURES
The primary outcome was EA at age 12 months. Egg allergy was defined as sensitization to egg white or ovomucoid plus a positive test result in an oral food challenge or an episode of obvious immediate symptoms after egg ingestion.
RESULTS
Of the 380 newborns included (198 [52.1%] female), 367 (MEC: n = 183; MEE: n = 184) were followed up for 12 months. On days 3 and 4 after delivery, the proportions of neonates with ovalbumin and ovomucoid detection in breast milk were higher in the MEC group than in the MEE group (ovalbumin: 10.7% vs 2.0%; risk ratio [RR], 5.23; 95% CI, 1.56-17.56; ovomucoid: 11.3% vs 2.0%; RR, 5.55; 95% CI, 1.66-18.55). At age 12 months, the MEC and MEE groups did not differ significantly in EA (9.3% vs 7.6%; RR, 1.22; 95% CI, 0.62-2.40) or sensitization to egg white (62.8% vs 58.7%; RR, 1.07; 95% CI, 0.91-1.26). No adverse effects were reported.
CONCLUSIONS AND RELEVANCE
In this randomized clinical trial, EA development and sensitization to eggs were unaffected by MEC during the early neonatal period.
TRIAL REGISTRATION
UMIN Clinical Trials Registry: UMIN000027593.
Topics: Infant; Infant, Newborn; Humans; Female; Male; Egg Hypersensitivity; Breast Feeding; Ovalbumin; Mothers; Ovomucin; Single-Blind Method; Milk, Human
PubMed: 37428506
DOI: 10.1001/jamanetworkopen.2023.22318 -
International Archives of Allergy and... 2022Molecular studies of hen's egg allergens help define allergic phenotypes, with IgE to sequential (linear) epitopes on the ovomucoid (OVM) protein associated with a...
INTRODUCTION
Molecular studies of hen's egg allergens help define allergic phenotypes, with IgE to sequential (linear) epitopes on the ovomucoid (OVM) protein associated with a persistent disease. Epitope profiles of other egg allergens are largely unknown. The objective of this study was to construct an epitope library spanning across 7 allergens and further evaluate sequential epitope-specific (ses-)IgE and ses-IgG4 among baked-egg reactive or tolerant children.
METHODS
A Bead-Based Epitope Assay was used to identify informative IgE epitopes from 15-mer overlapping peptides covering the entire OVM and ovalbumin (OVA) proteins in 38 egg allergic children. An amalgamation of 12 B-cell epitope prediction tools was developed using experimentally identified epitopes. This ensemble was used to predict epitopes from ovotransferrin, lysozyme, serum albumin, vitellogenin-II fragment, and vitellogenin-1 precursor. Ses-IgE and ses-IgG4 repertoires of 135 egg allergic children (82 reactive to baked-egg, the remaining 52 tolerant), 46 atopic controls, and 11 healthy subjects were compared.
RESULTS
183 peptides from OVM and OVA were screened and used to create an aggregate algorithm, improving predictions of 12 individual tools. A final library of 65 sequential epitopes from 7 proteins was constructed. Egg allergic children had higher ses-IgE and lower ses-IgG4 to predominantly OVM epitopes than both atopic and healthy controls. Baked-egg reactive children had similar ses-IgG4 but greater ses-IgE than tolerant group. A combination of OVA-sIgE with ses-IgEs to OVM-023 and OVA-028 was the best predictor of reactive phenotype.
CONCLUSION
We have created a comprehensive epitope library and showed that ses-IgE is a potential biomarker of baked-egg reactivity.
Topics: Allergens; Animals; Chickens; Egg Hypersensitivity; Epitopes; Female; Humans; Immunoglobulin E; Immunoglobulin G; Ovalbumin; Ovomucin; Peptides; Vitellogenins
PubMed: 34818647
DOI: 10.1159/000519618