Hen Egg Albumin Research Articles

Investigation of The Stability of The Lysozyme in Magnetic Particles for Drug Delivery

This research investigated lysozyme stability in the presence of magnetic particles for drug delivery. Lysozyme can mostly be found in the hen egg albumin, and it also acts as an essential agent, which is antibodies to fight harmful bacteria or shield the human body. The problems in this research are magnetic particles that can cause toxicity and reduce the therapy's efficiency due to the degradation of carriers (drugs). To minimise this problem, the stability and activity of the lysozyme and Fe2O3 were investigated. The structure of lysozyme and Fe2O3 before and after adding acid or alkaline was defined, and the suitability of Fe2O3 as a drug delivery was determined. The stability of the lysozyme and Fe2O3was identified using an Ultraviolet-Visible (UV-Vis) Spectrophotometer, and the structure was investigated using a Field Emission Scanning Electron Microscope (FESEM) and Scanning Electron Microscope- Energy Dispersive X-Ray (SEM-EDX). Different concentrations become the parameters of this research as a comparison between the samples. This research found that the combination of the lysozyme alkaline material was suitable for the body at a pH of 12.2. It also found that Fe2O3 is ideal for drug delivery in the body when the lysozyme can be carried by Fe2O3 and dissolved in the Fe2O3.

Enhanced Performance of Immobilized Rhizopus oryzae Lipase on Coated Porous Polypropylene Support with Additives

The immobilization of Rhizopus oryzae lipase (RoL) by hydrophobic adsorption on polypropylene supports with additives was investigated. Additives such as hen egg albumin, sodium caseinate and CAVAMAX® W6 were used to coat the support during immobilization where the immobilized RoL on coated support was compared to those of noncoated support. Following the immobilization, the catalytic activity of immobilized RoL was characterized based on different temperatures and pH. The immobilized RoL without additives showed optimal lipase activity at an optimum temperature of 50 °C and pH 6. However, RoL lipase that was immobilized on support treated with CAVAMAX® W6 had better performance in terms of hydrolytic activity and stability as compared to other additives. In addition, by having a support treated with hen egg albumin, the immobilized RoL was capable of yielding higher ester during esterification reactions.

Powerful Antibacterial Peptides from Egg Albumin Hydrolysates.

Native egg albumin (NEA) was isolated from hen eggs and hydrolyzed by pepsin to produce hydrolyzed egg albumin (HEA). HEA was chemically characterized and screened for its antibacterial activity against 10 pathogenic bacteria (6 Gram (+) and 4 Gram (−)). The SDS-PAGE pattern of NEA showed molecular weights of hen egg albumin subunits ranging from 30 to 180 kDa. The highest intensive bands appeared at a molecular mass of about 50 and 97 kDa. Ultra-performance liquid chromatography (UPLC) of the peptic HEA revealed 44 peptides, 17 of them were dipeptides, and the other 27 fractions corresponded to bigger peptides (3–9 amino acids). The dipeptides and big peptides represented 26% and 74% of the total hydrolysate, respectively. The MIC of HEA was about 100 μg/L for Listeria monocytogenes, Bacillus cereus, Staphylococcus aureus, Salmonella typhimurium, Streptococcus pyogenes, and Klebsiella oxytoca and 150 μg/L for Pseudomonas aeruginosa, Bacillus subtilis, and Listeria ivanovii and 200 μg/L for Escherichia coli. L. monocytogenes was the most sensitive organism to HEA. Mixtures of HEA with antibiotics showed more significant antibacterial activity than individually using them. Transmission electron microscopy (TEM) revealed various signs of cellular deformation in the protein-treated bacteria. HEA may electrostatically and hydrophobically interact with the cell wall and cell membrane of the susceptible bacteria, engendering large pores and pore channels leading to cell wall and cell membrane disintegration. Higher cell permeability may, thus, occur, leading to cell emptiness, lysis, and finally death. Alternatively, no toxicity signs appeared when HEA was administrated to Wistar Albino rats as one single dose (2000, 5000 mg/kg body weight) or repeated daily dose (500 and 2500 mg/kg body weight/day) for 28 days to disclose the possible toxicity hazards. HEA did not produce any death.

Chemical Composition and Nutritional Evaluation of Pasteurized Egg Melange

Egg is a basic foodstuff in many cultures and has a special place, also represent a rich source of nutrients such as, high quality proteins and a large variety of minerals and vitamins. The main derived products which are processed nowadays are dehydrated products (egg powder) and the liquid ones (refrigerated or frozen) as well as pasteurized egg m�lange which was the studied food in the current research. A number of 20 samples of egg m�lange were gathered from two different processing units. Samples were subjected to chemical analysis being determined content in water, dry matter, proteins, lipids, minerals, non-nitrogenous extractive substances, fatty acids and amino acids. Based on the obtained values was realised a nutritional evaluation for the analysed product by calculating the chemical indexes of essential amino acids (CI), essential amino acids index (EAAI), biological value (BV) and nutritional index (NI) for three categories of persons (children, young people and adults). The results of the current study showed the fact that chemically speaking, the analysed pasteurized egg m�lange presented values which were into the limits from literature; the analysed samples contented 75.59% water, 24.41% dry matter, 12.22% protein, 9.71% lipids, 0.99% total minerals, 1.48% non-nitrogenous extractive substances, 12.34 g/100 g content in amino acids (5.5 g/100 g essential amino acids) and 22.86 g/100 g lipids for polyunsaturated fatty acids. After nutritional evaluation of proteins from the studied food we observed that those ones had a very close value (EAA=50.77 g/16 g N) to the one of hen egg albumen (51.2 g/16 g N), value which is considered etalon. Calculus of some foresight indicators for nutritional value of proteins from studied egg m�lange showed the fact that this one could represent a good source of proteins and implicitly of essential amino acids for humans even if in children�s case the values were a little bit lower and two amino acids (tryptophan and leucine) were slightly limiting.

Novel adjuvants derived from attenuated lipopolysaccharides and lipid As of purple non-sulfur photosynthetic bacteria

Adjuvants are substances that enhance adaptive immune response to antigen. Development of a safe and effective immunostimulant adjuvant is essential for the efficacy of a vaccine to protect against infectious pathogens. Purple non-sulfur photosynthetic bacteria exhibited nontoxic natural lipid A variants that are distinct in their chemical structures from that of the Escherichia coli-type lipid A. In this study, the adjuvant efficacy of attenuated lipid A variants and their corresponding lipopolysaccharides (LPSs), derived from purple photosynthetic bacteria (Rhodocyclus tenuis and Rhodobacter sphaeroides) were evaluated. LPS was extracted using modified phenol-chloroform-petroleum ether method and lipid A was separated by mild acid hydrolysis. Trinitrophenol (TNP) was conjugated to hen egg albumin (TNP-HEA) and used as haptenic antigen. The LPS and lipid A adjuvant candidates were formulated in oil-in-water emulsion (OIWE) and evaluated to elicit anti-TNP IgG against TNP-HEA conjugate in BALB/c female mice. The anti-TNP IgG titers were measured using ELISA. The intact LPS-based adjuvants present in OIWE formulation showed significantly higher efficacy to elicit anti-TNP IgG titers against TNP-HEA conjugate compared to their corresponding lipid A-based adjuvants. As expected, the OIWE formulations of all LPS- and lipid A-based adjuvant candidates showed higher activities compared to the aqueous formulations. Slow reduction in the levels of anti-TNP IgG antibodies in the serum was observed over 4 months after immunization using the LPS- and lipid A-based adjuvant candidates which may provide a long protection against pathogens. The attenuated LPSs and lipid A’s from the photosynthetic bacteria showed promising results to develop novel safe and effective adjuvants that can evoke the immune response. The most promising adjuvant candidate was the LPS-based adjuvant from R. tenuis.

Synthesis and Characterization of hen egg albumin and Gelatin composite cross linked with Glutaraldehyde

Synthesis and Characterization of hen egg albumin and Gelatin composite cross linked with Glutaraldehyde

ISOLASI LISOZIM ALBUMIN TELUR AYAM RAS DENGAN METODE KROMATOGRAFI PENUKAR ION

Lyso z yme is one of the proteins found in hen egg albumin. Besides known as antimicrobial agents , lysozyme hydrolysis products can also function as antioxidants and as angiotensin converting enzyme (ACE ) inhibitors. The lysozyme is also known to have lysine and arginine that can give a sweet taste . The research aimed to isolate lysozyme from commercial laying hen eggs. The isolation and purification of the eggs lysozyme was done by preparative and analytical separation technique using cation exchange resins. The preparative separation was carried out by centrifugation of a large sample size of 205 g by centrifuga - tion, while the analytical separation only used only 3.16 g sample with a column measuring 13 cm in length and 3 cm in diameter . The number of samples isolated by preparative separation is greater than tha t with analytical method . The preparative separation was conducted in order to obtain the pure isolated lysozyme in higher quantity for further testing purposes. The purity of the isolated lysozyme from preparative separa-tion was 68.62% and the purity of isolated lysozyme from analytical separation was 63.03%.

Digestion differently affects the ability of native and thermally aggregated ovalbumin to trigger basophil activation

Ovalbumin (OVA), a major allergen from hen's egg albumen, tends to aggregate when heated. Depending on the balance of attractive and repulsive interactions, heat-induced OVA aggregates have various morphologies, which differ in digestibility. In the context of food allergy to egg, we investigated the ability of native and thermally aggregated OVA as well as their digests to induce the degranulation of a humanized rat basophil leukemia (RBL) cell line, which was sensitized with a pool of sera from egg-allergic children. Native and two thermally aggregated OVA forms were digested in vitro using a gastrointestinal digestion model based on the INFOGEST harmonized protocol including a final degradation with jejunal brush border membranes (BBM) enzymes. The course of digestion was monitored by the OPA method and by RP-HPLC. Digestibility was OVA small aggregates>OVA large aggregates>>native OVA and BBM peptidases only significantly hydrolyzed small-sized peptides from gastro-duodenal digests of the aggregates. The degranulation ability of the native OVA slightly changed during the gastric phase but mostly decreased during the duodenal digestion with no further change with BBM digestion. The degranulation ability of aggregates, which was significantly lower than the ability of native OVA, was not significantly affected by digestion. Digestibility and ability to induce basophil degranulation can thus not be straightforward linked.

Solubilization by freeze-milling of water-insoluble subunits in rice proteins.

This study investigates the effects of freeze-milling on the structural and functional properties of rice proteins (RPs). Sodium dodecyl sulfate-polyacrylamide gel electrophoresis showed that freeze-milling slightly influences the subunit bands of the RPs. Secondary and tertiary structures were studied by analyzing Fourier transform infrared spectra, sulfhydryl and disulfide bond contents, and surface hydrophobicities. The freeze-milled RPs (FMRPs) may possess an unfolded conformation that exposes buried functional groups. In addition, the solubility of the FMRPs is higher than that of the control, probably due to the exposure of water-protein interaction areas. In particular, the solubility of the FMRPs treated at a pH of 12.5 was 42 times that of the control. Characterization of functionalities demonstrated that both the emulsifying and foaming activities of the FMRPs were improved by solubilization. However, functional stabilities either remained unaffected or deteriorated. Generally, the FMRPs showed better emulsifying activities and stabilities than bovine serum albumin, alongside better foaming activities and stabilities than hen egg albumin. FMRPs may be of great interest to the food industry.

Comparison Study on Changes of Antigenicities of Egg Ovalbumin Irradiated by Electron Beam or X-Ray.

This study was conducted to compare the effects of two forms of radiation (electron and X-ray; generated by an electron beam accelerator) on the conformation and antigenic properties of hen’s egg albumin, ovalbumin (OVA), which was used as a model protein. OVA solutions (2.0 mg/mL) were individually irradiated by electron beam or X-ray at the absorbed doses of 0 (control), 2, 4, 6, 8, and 10 kGy. No differences between the two forms of radiation on the structural properties of OVA were shown by spectrometric and electrophoretic analyses. The turbidity of OVA solution increased and the main OVA bands on polyacrylamide gels disappeared after irradiation, regardless of the radiation source. In competitive indirect enzyme-linked immunosorbent assay, OVA samples irradiated by electron beam or X-ray showed different immunological responses in reactions with monoclonal and polyclonal antibodies (immunoglobulin G) produced against non-irradiated OVA. The results indicate that electron beam irradiation and X-ray irradiation produced different patterns of structural changes to the OVA molecule.

Exfoliation of montmorillonite in protein solutions

In the study we demonstrate a method to obtain stable, exfoliated montmorillonite–protein complexes by adsorption of the proteins extracted from hen-egg albumen. Analysis of the process by means of sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS–PAGE) revealed that the complexes are formed by sequential adsorption of ovotransferrin, ovalbumins, ovomucoid and lysozyme on the surface of the silicate. Structural studies performed by X-ray diffraction (XRD) and transmission electron microscopy (TEM) indicated that the adsorption of ovotransferrin and albumins is accompanied by disintegration of clay stacks into discrete platelets. Further analysis by dynamic light scattering (DLS) revealed that at protein to silicate weight ratios exceeding 20, the synergistic adsorption of albumen components leads to reaggregation of silicate platelets into disordered, microgel-like particles. By means of DLS it was found that exfoliation predominantly leads to formation of particles with average hydrodynamic radii (Rh) of 0.19μm while their aggregation causes formation of particles having Rh in of approx. 0.5μm and larger.

エチルエステル化卵白アルブミンによる珪藻土の凝集

タンパク質を原料とした生物分解性凝集剤の開発を目的として，0.1 M塩酸エタノール溶液でエチルエステル化した卵白アルブミン（EtOA）の凝集剤としての性能を，珪藻土懸濁液をモデル系とした比濁法と沈降天秤法によって，ポリ塩化アルミニウム（PAC）と比較評価した．EtOAを珪藻土に対して1 wt%以上添加することにより高い凝集効果が得られ，凝集体の初期沈降速度は最大0.005 m·s−1であった．凝集体沈降速度はpH 7–10でpHの増加とともに0.003 m·s−1まで低下したが，pH 4–10でPACより高い凝集効果を示した．

Monolithic macroporous albumin/chitosan cryogel structure: a new matrix for enzyme immobilization

A novel monolithic macroporous material was developed by cross-linking hen egg albumin (HEA) and chitosan with glutaraldehyde at subzero temperatures. A macroporous cryogel structure allowed efficient mass transport of solutes within the material. In one application, albumin was partially replaced with active enzymes (glucose oxidase and horseradish peroxidase) resulting in the production of macroporous biocatalyst preparations suitable for flow-injection analysis of glucose in the low millimolar range. In another application, the proteolytic enzymes savinase and esperase were coupled to the macroporous structure via free amino groups on the pore walls using glutaraldehyde as cross-linker/spacer agent. The low hydraulic resistance of the matrix allowed for the development of a generic, high-performance online protein digestion system utilizing the wall-bound proteases.

Isolation of lysozyme from hen egg albumen using glass fiber-based cation-exchange membranes

In this study, porous glass fiber membranes were coated with monophenyl trimethoxysilane (MPh) and then sulphonated by chlorosulphonic acid to prepare the cation-exchange membranes with sulphonic acid groups. Different MPh-coating times were tested and the properties of the resulting membranes such as contact angle, FTIR spectrum, conductivity, and ion-exchange capacity were measured. It was found that the optimal MPh-coating time was 60 min and the related ion-exchange capacity was 49.5 μequiv./disc. The modified membrane under the optimal MPh-coating condition was adopted for lysozyme isolation. The results were compared with those for the commercial cation-exchange membrane with sulphonic acid groups (ICE 450 unsupported membrane). Although the prepared membrane exhibited less adsorption capacity than ICE 450 unsupported membrane in the batch lysozyme adsorption experiment, it showed lower non-specific binding ratio under higher salt concentration. In the flow process isolating lysozyme from hen egg albumen, the purification effectiveness obtained using the prepared cation-exchange membrane was superior to the ICE 450 unsupported membrane.

Comparison of the changes of the antigenicities of a hen's egg albumin by a gamma and an electron beam irradiation

The study was conducted to compare the radiation types of a gamma ray and an electron beam for the inhibition and reduction of a food allergy. OVA (2 mg/ml) were irradiated at 3, 5, 7 and 10 kGy. Patterns detected by the SDS-PAGE and an immunoblot showed that the intact OVA band disappeared and that it was dependant upon the radiation doses regardless of the radiation types. Binding abilities of the irradiated OVA against the monoclonal IgG and the egg allergic patients’ IgE decreased due to a conformational change of the epitope, but differences from using the two different radiation types were not observed. The results indicate that both the radiation types can be used for an inhibition and a reduction of a food allergy regardless of the radiation types.

Influence of Flour Type on Mechanical Properties of Calcium-Induced Egg Albumen-Flour Composite Gel

The mechanical properties of composite network of hen egg albumen (EA) and flours; i.e., rice flour (RF) and/or cassava starch (CS) formed at 80 degree C using a salt-induced two-step gelation process were investigated. This structure-forming process induced gelation of pre-heated EA suspension in the presence of calcium ion and subsequent gelatinization of starch during the second heating regime. Increasing calcium lactate concentration up to 50 mM increased the aggregation of EA suspension and the Young’s modulus of EA gel. Above 50 mM, both aggregation of EA suspension and Young’s modulus of EA gel decreased. Addition of flour fillers to the EA suspension increased Young’s modulus, stress at fracture, initial stress at 20% deformation and residual stress after 20% deformation for 5 min. Raising the calcium lactate concentration influenced the mechanical characteristics of only EA-RF and EA-RF-CS but had no effect on those of EA-CS gel. The composite gels containing RF were more rigid than the ones containing CS. The EA-CS composite gel relaxed faster and to a much greater extent than the EA-RF gel. This was likely due to the high capacity of CS to absorb water, which weakened the strength of the granule after the composite structure was heated during the structure-forming process. Overall, results suggest that different flour fillers create composite gels with different mechanical properties due to the different pasting characteristics of flour constituents.

A proton NMR relaxation study of hen egg quality

A quantitative analysis of NMR proton relaxation in hen egg albumen and yolk is undertaken to research the causes of quality loss during the first few days of storage and to access the feasibility of an on-line NMR sensor of internal egg quality. It is shown that the change in the transverse relaxation in thick egg albumen mainly results from an increase in proton exchange rate resulting from a pH increase attributed to loss of carbon dioxide by diffusion through the eggshell. The results suggest that the low-field T1 is the best relaxation time indicator of albumen quality.

Modulation of the primary and the secondary antibody response by tobacco smoke condensates

Cigarette smoke condensate administered to C57BL/6 mice led to a decrease in the primary antibody response to OVA (hen egg albumin) antigen. Selenium (Se)-supplementation allowed to relieve significantly this inhibition. Moreover, even being not supplemented with Se, a preparation was found devoid of inhibitory effects. Furthermore, the presence of Se-supplemented tobacco smoke condensate at the time of antigen priming, contributed to an enhanced secondary antibody response.

Determination of Ovalbumin in Processed Foods by Immunological Methods

Allergens in processed foods may place persons with food allergies at significant risk when the labels do not provide sufficient warnings or identification of high-risk ingredients. Because egg proteins are common food allergens, this study was carried out to identify hen's egg albumin (ovalbumin, OVA) in five commercially processed foods containing egg (custard, cookie and pasta), and chicken meat (sausage and meatball) by immunological methods using commercially produced murine monoclonal immunoglobulin G (M-IgG), immunoblotting and enzyme linked immunosorbent assay (ELISA). Sample buffer with chelating and reducing agents was prepared and used for the preparation of the protein fractions from the foods. Most bands in sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) profile (5～15% gradient gel) presented at 75 kDa below. OVA (43 kDa) in the sample lanes could not be visually observed on the gel. However, OVA in solutions prepared from custard and cookie could be detected by M-IgG, but were not detected in sausage and pasta. OVA in all samples could be quantitatively determined by the equation obtained from the standard curve by ELISA. Cookie and custard containing egg white and egg, respectively, contained very high concentrations of OVA. OVA in the other products were present in relatively low concentrations, but sufficiently high to pose possible risk of allergy. ELISA is a very sensitive and precise method for the identification and quantification of allergens in food products including allergy-inducible materials.

Changes in the Antigenic and Immunoglobulin E–Binding Properties of Hen's Egg Albumin with the Combination of Heat and Gamma Irradiation Treatment

This study was carried out to evaluate the changes in the allergenic and antigenic properties of hen's egg albumin (ovalbumin [OVA]) with the combination of heat and gamma irradiation treatment. OVA solution samples were treated by (i) heating (sample 1), (ii) irradiation after heating (sample 2), and (iii) heating after irradiation (sample 3). Samples were isothermally heated and irradiated at the absorption dose of 10 kGy. Competitive indirect enzyme-linked immunosorbent assays (ELISAs) were performed with blood serum to test the ability of treated OVA to bind to immunoglobulin E (IgE) and mouse murine monoclonal antibody (IgG). OVA's ability to bind to mouse IgG changed upon heating at 75°C, and its ability to bind to egg-allergic IgE changed upon heating at 80°C. The ELISAs showed that egg-allergic IgE did not recognize OVA very well when heated at ≥80°C, while mouse IgG retained better activity under these conditions. Egg-allergic IgE binding was low both for OVA samples treated by heating and for samples treated by irradiation followed by heating. These results show that allergies induced by OVA could be effectively reduced by the combination of heat and gamma irradiation treatment.