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Xiaohong Sun - One of the best experts on this subject based on the ideXlab platform.
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Glycopeptides from egg white Ovomucin inhibit K88ac enterotoxigenic Escherichia coli adhesion to porcine small intestinal epithelial cell-line
Journal of Functional Foods, 2019Co-Authors: Xiaohong Sun, Michael G. GänzleAbstract:Abstract Anti-adhesive therapy is emerging as an alternative approach to antibiotics against bacterial infection. The anti-adhesive activity of Ovomucin hydrolysates against K88ac enterotoxigenic Escherichia coli (ETEC) strains adhesion to porcine small intestinal epithelial cell-line (IPEC-J2) was confirmed using both the plate counting and Syto 9 staining methods. Ovomucin-protex 26L hydrolysate, with the minimum effective concentration of 2.5 g/L, showed the best anti-adhesive activity. Immunofluorescence assay suggested that Ovomucin hydrolysates did not decrease the binding capacity of IPEC-J2 cells to K88 fimbriae. Interactions between Ovomucin-protex 26 L hydrolysate and purified K88ac fimbriae indicated the anti-adhesive activity of Ovomucin hydrolysates was due to their decoying properties for competitive binding to ETEC through K88ac fimbriae. The responsible glycopeptides in Ovomucin-protex 26 L hydrolysate was purified by affinity chromatography and nine peptide sequences and twelve possible glycans were identified. Ovomucin derived glycopeptides may have the potential for use as an anti-adhesive agent against infectious diseases.
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Protein-Resistant Property of Egg White Ovomucin under Different pHs and Ionic Strengths.
Journal of agricultural and food chemistry, 2018Co-Authors: Xiaohong Sun, Jun Huang, Hongbo ZengAbstract:Ovomucin is a mucin-type glycoprotein accounting for 3.5% (w/w) of total egg white proteins. The purpose of the study was to explore the potential of Ovomucin as a protein-resistant material. Using bovine serum albumin (BSA) as a model protein, Ovomucin decreased the fluorescence intensities of the adsorbed BSA from 10.90 ± 2.18 to 0.67 ± 0.75, indicating its protein-resistant property. To understand the underlying mechanism, pure repulsive forces between Ovomucin and model proteins (e.g., BSA and Ovomucin) at various pHs (2.0, 6.0, and 7.2) and ionic strengths (0.1, 10, and 150 mM NaCl) were measured using a surface forces apparatus. Further studies by using atomic force microscope imaging, zeta potential, and dynamic light scattering suggested that the protein-resistant property of Ovomucin was mainly attributed to strong electrostatic and steric repulsions between protein layers. This work has demonstrated that Ovomucin has antifouling potential with broad applications in the areas of food processing industry and biomedical implants.
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protein resistant property of egg white Ovomucin under different phs and ionic strengths
Journal of Agricultural and Food Chemistry, 2018Co-Authors: Xiaohong Sun, Jun Huang, Hongbo ZengAbstract:Ovomucin is a mucin-type glycoprotein accounting for 3.5% (w/w) of total egg white proteins. The purpose of the study was to explore the potential of Ovomucin as a protein-resistant material. Using...
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identification and characterization of glycopeptides from egg protein Ovomucin with anti agglutinating activity against porcine k88 enterotoxigenic escherichia coli strains
Journal of Agricultural and Food Chemistry, 2017Co-Authors: Xiaohong Sun, Michael G. GänzleAbstract:Ovomucin is a glycoprotein from egg white with potential to act as an anti-adhesive agent against infectious diseases. This study aimed to determine whether Ovomucin or Ovomucin hydrolysates could prevent adhesion of two porcine K88 enterotoxigenic Escherichia coli (ETEC) strains. Adhesion was assessed in vitro using a hemagglutination assay. Ovomucin hydrolysates, but not intact Ovomucin, prevented adhesion of ETEC to porcine erythrocytes. The Ovomucin hydrolysate prepared by acid protease II exhibited the best anti-agglutinating activity against both strains; this hydrolysate was fractionated by cation exchange chromatography and reverse-phase high-performance liquid chromatography (HPLC). The most active fractions, F3(9) and F7(1), with minimal inhibitory concentrations of 0.03 and 0.25 g/L against strains ECL13795 and ECL13998, respectively, were subjected to structural characterization. Six identified glycopeptides were all derived from α-Ovomucin, composed of a pentasaccharide core of two N-acetylgl...
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effect of proteolysis on the sialic acid content and bifidogenic activity of Ovomucin hydrolysates
Food Chemistry, 2016Co-Authors: Xiaohong Sun, Michael G. Gänzle, Catherine J FieldAbstract:Ovomucin, accounting for ∼3.5% of egg white proteins, contains 2.6-7.4% of sialic acid; sialic acid is suggested to play important roles in host-recognition, cognition and memory development. However, Ovomucin's limited water solubility might restrict its future applications. The objective of the study was to examine the effect of proteolysis of Ovomucin on the sialic acid content and bifidogenic activity of Ovomucin hydrolysates. Ovomucin extract was hydrolyzed by 14 proteases with yields and DHs ranging from 42.6% (flavourzyme) to 97.4% (protease N), and 2.4% (flavourzyme) to 46.3% (pronase), respectively. Ovomucin hydrolyzed by pronase and protex 26L showed molecular weight (Mw) distributions less than 40kDa while others larger than 200kDa. Allergenicity of Ovomucin hydrolysates was significantly reduced (P<0.05) in comparison to Ovomucin extract. The content of sialic acid in hydrolysates ranged from 0.1% (protex 26L) to 3.7% (pronase). Ovomucin hydrolysates did not generally support growth of Bifidobacterium spp. in vitro.
Yuanyuan Shan - One of the best experts on this subject based on the ideXlab platform.
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potential role of Ovomucin and its peptides in modulation of intestinal health a review
International Journal of Biological Macromolecules, 2020Co-Authors: Xue Zhao, Yuanyuan ShanAbstract:Intestinal dysfunction, which may cause a series of metabolic diseases, has become a worldwide health problem. In the past few years, studies have shown that consumption of poultry eggs has the potential to prevent a variety of metabolic diseases, and increasing attention has been directed to the bioactive proteins and their peptides in poultry eggs. This review mainly focused on the biological activities of an important egg-derived protein named Ovomucin. Ovomucin and its derivatives have good anti-inflammatory, antioxidant, immunity-regulating and other biological functions. These activities may affect the physical, biological and immune barriers associated with intestinal health. This paper reviewed the structure and the structure-activity relationship of Ovomucin，the potential role of Ovomucin and its derivatives in modulation of intestinal health are also summarized. Finally, the potential applications of Ovomucin and its peptides as functional food components to prevent and assist in the pretreatment of intestinal health problems are prospected.
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rheological and structural properties of Ovomucin from chicken eggs with different interior quality
Food Hydrocolloids, 2020Co-Authors: Yuanyuan Shan, Dengyu Tang, Rong Wang, Xin Wang, Bianfang Liu, Yuan Zhou, Qun HuangAbstract:Abstract Ovomucin is hypothesized to be responsible for the gel-like nature of egg white. However, few investigations have revealed the rheological property and conformational alterations of Ovomucin from eggs with different interior quality. In this study, Ovomucin was isolated from eggs with different Haugh unit (HU) values, ranging from 80 to 30 as a result of storage. The viscoelasticity and structural characteristics of Ovomucin were analyzed using rheology, DLS, fluorescence, CD and FTIR spectroscopy. Rheological data revealed a significant decrease in the viscosity and elastic modulus (G′) of Ovomucin gel with decreasing HU value. The same trend was observed in the Ovomucin content. The particle size distribution results showed the smaller average particle size and wider distribution range of the Ovomucin from low HU eggs. When the HU decreased from 80 to 64, the blue shift and disappearance in infrared absorption peaks at 800-1200 cm−1 confirmed the dissociation of glycosidic bond in Ovomucin. Infrared and CD spectroscopic results demonstrated that the Ovomucin undergoes a transition from intermolecular β-sheet and α-helix structure to random coil structure when HU decreased from 80 to 64, and the stretched protein re-forms an ordered secondary structure such as β-turn when HU further decreased from 53 to 30. There was an intermediate form in the secondary structure of Ovomucin from eggs with HU between 64 and 53, indicating that the conformational transition of Ovomucin does not fit the simple two-state mechanism. Zeta potential and hydrophobicity measurements further confirmed the existence of intermediate state.
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assessment of the relationship between Ovomucin and albumen quality of shell eggs during storage
Poultry Science, 2019Co-Authors: Yiyang Wang, Zihao Wang, Yuanyuan ShanAbstract:Ovomucin is known to be critical for keeping the high quality and freshness of thick albumen, but there is lack of understanding on the dynamics changes of this important protein during storage. This study aimed to investigate the relationship between Ovomucin content and egg freshness during storage. Firstly, the viscoelasticity of albumen was shown to be much higher than that of Ovomucin-depleted albumen from rheological analysis results, indicating that Ovomucin is an important component in maintaining the natural viscoelasticity of albumen. Then, the Ovomucin content determined by ELISA method was compared to albumen pH, Haugh unit (HU), and yolk index in terms of egg white quality and to the time of storage in terms of egg freshness at 4°C, 25°C, and 37°C, respectively. Results of the transformation kinetic showed a decrease in Ovomucin content with prolonged storage time (P ≤ 0.01). Correlation analysis showed a high positive correlation between Ovomucin content and HU (P ≤ 0.01) and a high negative correlation between Ovomucin content and the albumen pH (P ≤ 0.01) at the test temperatures. We therefore conclude that Ovomucin content in albumen can be used as an index for egg freshness. At last, predictive models of the equivalent egg age (4°C and 25°C) for evaluating the egg freshness were established by means of exponential regression model with Ovomucin content as the variable. These results can provide a theoretical and technical basis for the storage and fresh evaluation of shell eggs.
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effectively preparing soluble Ovomucin with high antiviral activity from egg white
International Journal of Biological Macromolecules, 2018Co-Authors: Zihao Wang, Dengyu Tang, Yuanyuan ShanAbstract:Abstract Ovomucin has a great potential because of its numerous bioactivities, which makes it an attractive molecule for industrials. However, to isolate soluble Ovomucin without degradation and contamination remains a challenge. In this study, Ovomucin of high purity (99.13%) was obtained in good yield (3.02 g kg−1 fresh egg white) via an improved two-step precipitation followed by gel filtration chromatography. The IC50 of the preparation for three representative new disease virus strains named LaSota, Mukteswar and V-4 is 1.99, 4.95 and 5.78 × 10−3 g L−1, respectively. Produced Ovomucin showed limited reduction in the hemagglutination inhibition activity against all of the virus strains during the purification. Infrared spectroscopy of the Ovomucin preparation indicated extensive glycosylation and sulfation. Amino acid analysis found that it was rich in alanine, glutamic acid, threonine and valine residues, which is typical in mucins. The improved process developed in this study is an alternative approach to obtain pure Ovomucin with elevated antiviral activity and purity, which may significantly push forward the further research on bioactivities of Ovomucin.
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sialic acid involves in the interaction between Ovomucin and hemagglutinin and influences the antiviral activity of Ovomucin
International Journal of Biological Macromolecules, 2018Co-Authors: Yuanyuan Shan, Ning Wang, Yaping Liu, Maojie ZhangAbstract:Ovomucin (OVM) plays an important role in inhibiting infection of various pathogens. However, this bioactivity mechanism is not much known. Here, the role of sialic acid in OVM anti-virus activity has been studied by ELISA with lectin or ligand. Structural changes of OVM after removing sialic acid were analyzed by circular dichroism and fluorescence spectroscopy. OVM could be binding to the hemagglutinin (HA) of avian influenza viruses H5N1 and H1N1, this binding was specific and required the involvement of sialic acid. When sialic acid was removed, the binding was significantly reduced 71.5% and 64.35%, respectively. Therefore, sialic acid was proved as a recognition site which avian influenza virus bound to. Meanwhile, the endogenous fluorescence and surface hydrophobicity of OVM removing sialic acid were increased and the secondary structure tended to shift to random coil. This indicated that OVM molecules were in an unfolded state and spatial conformation disorder raising weakly. Remarkably, free sialic acid strongly promoted OVM binding to HA and thereby enhanced the interaction. It may contribute to the inhibition of host cell infection, agglutinate viruses. This study can be extended to the deepening of passive immunization field.
Dileep A Omana - One of the best experts on this subject based on the ideXlab platform.
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effect of shell eggs storage on Ovomucin extraction
Food and Bioprocess Technology, 2012Co-Authors: Jiapei Wang, Dileep A OmanaAbstract:Ovomucin, one of the major egg white proteins, has wide potential applications in food, functional food and nutraceutical industries due to its unique physicochemical properties and bioactivities. A new two-step method was recently developed to prepare high purity Ovomucin; in this study, effect of shell egg storage on Ovomucin extraction was investigated. The composition of Ovomucin extracts from egg white was determined by gel filtration chromatography. Both storage temperature and time could significantly (p < 0.05) affect the purity and yield of the Ovomucin. After 9 weeks of storage at 4 °C, the content of the Ovomucin in the extract decreased from 92.5% to 82.4%, and the yield of Ovomucin decreased from 214 to 120 mg/100 g of egg albumen (egg white). After 5 weeks of storage at 22 °C, the content of Ovomucin extract decreased from 92.5% to 73.0%, and the yield of Ovomucin decreased from 214 to 112 mg/100 g of egg albumen. Increase in egg white pH during prolonged storage leading to degradation of Ovomucin is very likely responsible for the decreased extractability of Ovomucin.
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Ovomucin a glycoprotein with promising potential
Trends in Food Science and Technology, 2010Co-Authors: Dileep A Omana, Jiapei WangAbstract:Ovomucin, accounting for ∼3.5% of total egg white protein, is responsible for the thick gel characteristics of liquid egg white. Besides its excellent foaming and emulsion capacities, it possesses anti-viral, anti-bacterial, anti-tumor and other bioactivities. This paper reviews compositional, structural, physicochemical, functional and biological properties of Ovomucin, as well as development of methods of extraction. As one of the least defined proteins in egg white, further study is required to characterize the structure and to explore its full potential in new applications as functional foods and nutraceuticals.
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co extraction of egg white proteins using ion exchange chromatography from Ovomucin removed egg whites
Journal of Chromatography B, 2010Co-Authors: Dileep A Omana, Jiapei Wang, Jianping WuAbstract:Efficient isolation of egg white components is desired due to its potential uses. Existing methods mainly targeted on one specific protein; an attempt has been made in the study to co-extract all the valuable egg white components in a continuous process. Ovomucin was first isolated by our newly developed two-step method; the resultant supernatant obtained after Ovomucin isolation was used as the starting material for ion-exchange chromatography. Anion-exchange chromatography of 100 mM supernatant yielded a flow-through fraction and three other fractions representing ovotransferrin, ovalbumin and flavoproteins. The flow-through fraction was further separated into ovoinhibitor, lysozyme, ovotransferrin and an unidentified fraction which represents 4% of total egg white proteins. Chromatographic separation of 500 mM supernatant resulted in fractions representing lysozyme, ovotransferrin and ovalbumin. This co-extraction protocol represents a global recovery of 71.0% proteins.
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effect of different concentrations of calcium chloride and potassium chloride on egg white proteins during isoelectric precipitation of Ovomucin
Poultry Science, 2009Co-Authors: Dileep A OmanaAbstract:Abstract The effect of various concentrations of CaCl2 and KCl on egg white proteins during isoelectric precipitation of Ovomucin was investigated in this study. At low concentrations of CaCl2 (
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a new method of separating Ovomucin from egg white
Journal of Agricultural and Food Chemistry, 2009Co-Authors: Dileep A OmanaAbstract:Ovomucin, a key component in maintaining the viscous nature of egg white, is a glycoprotein contributing to 2-4% of the total egg albumin protein. Preparation of pure Ovomucin remains a challenge due to the presence of coprecipitated proteins, mainly ovalbumin and lysozyme. The objectives of the study were to determine the effect of different salt concentrations on the extractability of Ovomucin and to develop a simple method to purify Ovomucin that could be adapted for further scale-up production. The protein compositions of Ovomucin extracts were significantly affected by salt concentrations. The concentration of ovalbumin was increased, whereas that of lysozyme was decreased in the Ovomucin extracts at increasing salt concentrations up to 500 mM; lysozyme was the major contaminant at low salt concentrations ( or=200 mM). A 2-step method was developed for the first time to prepare Ovomucin with a purity of greater than 90%. Egg white was first extracted in the presence of 100 mM NaCl at pH 6.0 to produce a precipitate containing moderate coprecipitated ovalbumin (14.6%) and lysozyme (15.9%); the contaminated proteins in the precipitate were further removed by using 500 mM NaCl. The yield of Ovomucin was determined to be 400.2 mg/100 g of egg white. This 2-step method is simple, environmentally friendly, and easy for scale-up preparation.
Kenji Watanabe - One of the best experts on this subject based on the ideXlab platform.
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antitumor effects of β subunit from egg white Ovomucin on xenografted sarcoma 180 cells in mice
Food Science and Technology Research, 1999Co-Authors: Takashi Yokota, Hifumi Ohishi, Kenji WatanabeAbstract:The intraperioneal administration of β-subunit prepared from egg white Ovomucin was found to suppress the growth of subcutaneously xenografted sarcoma-180 cells in mice and cure the tumor. In the present system, β-subunit (5 mg/kg of body weight) was injected to mice daily for 19 days after the 10th day when tumors had grown to 7 mm in diameter. The light and electron microscopic appearances of tumor portions on day 28 showed that β-subunit-treated tumor cells were in the states of degenerated and necrotic cells, and massive accumulations of neutrophils, macrophages and lymphocytes were found at the margin of the degenerated and necrotic tumor tissue area. These findings suggested that β-subunit brought about the regression of tumor, probably by activating the immune system.
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in vitro studies of cytotoxic effect on sarcoma 180 cells of β subunit from egg white Ovomucin
Food Science and Technology Research, 1999Co-Authors: Takashi Yokota, Hifumi Ohishi, Kenji WatanabeAbstract:When sarcoma-180 (SR-180) cells were incubated with α- or β-subunit prepared from insoluble Ovomucin in the gel fraction of egg white, the cell proliferation rate was apparently reduced by the addition of β-subunit, while it was largely unaffected by α-subunit. Examinations by scanning and transmission electronmicroscopy indicated a dose- and time-dependent cytotoxic effect of β-subunit on SR-180 cells, whereas β-subunit did not injure mouse peritoneum macrophage used as normal cells. Ultrastructurally, SR-180 cells treated with β-subunit showed changes such as swelling and bleb formation of microvilli on cell membrane, irregular clumping of chromatin, irregular nuclear shape, and marked swelling of organelles in cytoplasm associated with cell degeneration in necrotic change. Furthermore, apoptotic analysis of the cultured SR-180 cells also demonstrated that β-subunit did not induce the apoptotic DNA fragmentation.
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binding activities of pronase treated fragments from egg white Ovomucin with anti Ovomucin antibodies and newcastle disease virus
Journal of Agricultural and Food Chemistry, 1998Co-Authors: Kenji Watanabe, Yoji Tsuge, Makoto ShimoyamadaAbstract:The prepared gel-like Ovomucin and its β-subunit were treated with Pronase at various ratios (1/25600−1/6.25) to the sample weight at 37 °C for 24 h. The concentration, chemical composition, and SDS−polyacrylamide gel electrophoretic patterns of the obtained soluble fractions and their abilities to bind to anti-Ovomucin antibodies and Newcastle disease virus (NDV) were measured. At a ratio of 1/6400 the highest soluble fraction (solubility: nearly 100%) was obtained. At a ratio of 1/800 the fragment with the highest binding activity to the antibodies was obtained, and at a ratio of 1/50 the fragments with the disulfide bonds intact (apparent molecular masses, AMMs: 55, 45, and 40 kDa) which showed binding to the antibodies were prepared and partially characterized. Fragments (AMMs: 220, 120, and 100 kDa) at ratios of 1/3200−1/800 and the final Pronase-resistant fragment (AMM: 120 kDa) at ratios of 1/12.5−1/6.25 with a binding activity to NDV could then be prepared. From the analysis of the fragments o...
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bindings of Ovomucin to newcastle disease virus and anti Ovomucin antibodies and its heat stability based on binding abilities
Journal of Agricultural and Food Chemistry, 1997Co-Authors: Yoji Tsuge, Makoto Shimoyamada, Kenji WatanabeAbstract:The bindings of Ovomucin, its chemically modified compounds, including its disulfide-reduced and alkylated α- and β-subunits, and desialylated Ovomucin to NDV and anti-Ovomucin antibodies were determined by ELISA. We found that the NeuAc residue in the β-subunit greatly contributed to the binding of Ovomucin to NDV, and disulfide bonds in Ovomucin contributed to the binding of Ovomucin to antibodies. The conformational, biological, and chemical alterations of Ovomucin heated at 60−100 °C for 10 min under the various pH conditions (pH 6−12) were examined on the changes in the ability to NDV and anti-Ovomucin antibodies which were also determined by ELISA, along with determinations of SDS−PAGE patterns and CD spectra. Ovomucin degraded together with the increases in temperature and pH, depending on destruction of NeuAc in β-subunit, and cleavages of disulfide bonds in inter- and intrasubunits and peptide bonds in α- and β-subunits. Keywords: Ovomucin; newcastle disease virus; anti-Ovomucin antibodies; heat ...
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structural features of newcastle disease virus and anti Ovomucin antibody binding glycopeptides from pronase treated Ovomucin
Journal of Agricultural and Food Chemistry, 1997Co-Authors: Yoji Tsuge, Makoto Shimoyamada, Kenji WatanabeAbstract:Pronase-treated Ovomucin was applied on a Sephacryl S-400 column chromatography and separated into five fractions. The SDS-polyacrylamide gel electrophoretic pattern, and amino acid and carbohydrate compositions, of each of the obtained fractions were compared to those of Ovomucin and its α- and β-subunits. Subsequently, bindings of each fraction to hen newcastle disease virus (NDV) and anti-Ovomucin antibodies were estimated. It was found that the P1, P2, and P3 fractions from the β-subunit which were composed of O-glycoproteins, containing more or less clustered sialic acid moieties, had higher binding activity to NDV, while the peptide-rich P4 and P5 fractions mainly derived from the α-subunit had higher binding activity to the anti-Ovomucin antibodies.
Hongbo Zeng - One of the best experts on this subject based on the ideXlab platform.
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Protein-Resistant Property of Egg White Ovomucin under Different pHs and Ionic Strengths.
Journal of agricultural and food chemistry, 2018Co-Authors: Xiaohong Sun, Jun Huang, Hongbo ZengAbstract:Ovomucin is a mucin-type glycoprotein accounting for 3.5% (w/w) of total egg white proteins. The purpose of the study was to explore the potential of Ovomucin as a protein-resistant material. Using bovine serum albumin (BSA) as a model protein, Ovomucin decreased the fluorescence intensities of the adsorbed BSA from 10.90 ± 2.18 to 0.67 ± 0.75, indicating its protein-resistant property. To understand the underlying mechanism, pure repulsive forces between Ovomucin and model proteins (e.g., BSA and Ovomucin) at various pHs (2.0, 6.0, and 7.2) and ionic strengths (0.1, 10, and 150 mM NaCl) were measured using a surface forces apparatus. Further studies by using atomic force microscope imaging, zeta potential, and dynamic light scattering suggested that the protein-resistant property of Ovomucin was mainly attributed to strong electrostatic and steric repulsions between protein layers. This work has demonstrated that Ovomucin has antifouling potential with broad applications in the areas of food processing industry and biomedical implants.
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protein resistant property of egg white Ovomucin under different phs and ionic strengths
Journal of Agricultural and Food Chemistry, 2018Co-Authors: Xiaohong Sun, Jun Huang, Hongbo ZengAbstract:Ovomucin is a mucin-type glycoprotein accounting for 3.5% (w/w) of total egg white proteins. The purpose of the study was to explore the potential of Ovomucin as a protein-resistant material. Using...
