Egg White Albumin Research Articles

Foaming in wet flue gas desulfurization plants: Laboratory‐scale investigation of long‐term performance of antifoaming agents

Spontaneous foaming can cause a range of operational problems in industrial processes such as wet flue gas desulfurization (FGD). This work investigates the performance of selected antifoaming agents (Nalco FM‐37, Foamtrol 2290, and rapeseed oil) on foams generated by egg white albumin (protein), sodium dodecyl sulfate, and adipic acid at conditions of relevance for wet FGD plants. The addition of antifoaming agents breaks any existing foam and causes an induction period without foaming, after which the foam gradually will begin to reappear. Foaming by egg white albumin (2 g/L) at 0.014 m/s could be controlled by both commercial antifoaming agents (6.4 g/L), but not by rapeseed oil addition. Foaming by pure commercial antifoaming agents has also been demonstrated: up to 7 × 10−2 m foam was observed with 6.4 g/L Nalco FM‐37. © 2013 American Institute of Chemical Engineers AIChE J, 59: 3741–3747, 2013

Foam properties of algae soluble protein isolate: Effect of pH and ionic strength

In this study the foam properties of algae soluble protein isolate (ASPI), a mixture of mainly proteins and polysaccharides, were investigated as function of isolate concentration (0.1–1.0 mg/mL) and pH (3.0–7.0) at 10 mM and 200 mM NaCl. In addition, adsorption kinetics and dilatational elasticity at the air–water interface were studied. Whey protein isolate (WPI) and egg white albumin (EWA) were used as reference proteins. The consistent dilatational behaviour of ASPI at all pH values and ionic strengths tested indicated a similar interfacial composition at all these conditions. Adsorption kinetics, in contrast, were influenced by varying environmental conditions. At increased ionic strength and close to the theoretical isoelectric point calculated based purely on the amino acid composition of ASPI (pH 7) adsorption increased. Since similar adsorption behaviour was also observed for WPI and EWA, the interfacial properties of ASPI are most likely dominated by its protein fraction. This is further confirmed by the fact that ζ-potential measurements suggested an overall isoelectric point of ASPI below pH 3, while adsorption kinetics varied between pH 5 and pH 7 (the theoretical protein-based isoelectric point of ASPI). The overall foam stability of ASPI stabilized foams was superior to those of WPI and EWA in the pH range 5–7. In conclusion, the molecular and interfacial properties of ASPI, a mixture of proteins and polysaccharides, seem to favour the production of very stable foams in this pH range by the selective adsorption of its protein fraction to the air–water interface.

Development of protein-based bioplastics with antimicrobial activity by thermo-mechanical processing

This study focuses on the development of new bio-active protein-based bioplastics through a thermo-mechanical processing, which involves a first compounding step followed by compression-moulding of the resulting material into the desired shape. Two types of proteins, wheat gluten and egg-white albumen, and two different bioactive agents, formic acid and oregano essential oil, were selected. The effect of biocide addition on the material rheological response, its antimicrobial activity and biocide release behaviour have been assessed. Rheological tests demonstrated that formulation and processing may exert a notable effect on the material linear viscoelasticity. Kirby–Bauer tests carried out on four selected types of microorganisms revealed that oregano essential oil into a wheat gluten-based matrix may be suitable for applications where the active agent must be progressively delivered (for up to 7days). Moreover, this biocide can inhibit microorganisms’ growth even if the bioplastic is not in direct contact with the substrate.

Protein Foaming-Consolidation Method for Fabrication of High Performance Porous Bioceramics

Protein foaming-consolidation method is a facile technique for production of porous materials using egg yolk as pore creating agent. Usage of the yolk in the process offers a number of advantages over other proteins such as egg white and bovine serum albumin (BSA). Various materials were successfully fabricated using this technique. The present paper gives a brief review of the preparation and characterization of the materials through protein foaming-consolidation technique for biomedical application.

Jojoba Oil/Water Emulsions Stabilized by BSA and Egg Proteins: A Study Using Conductivity Technique

Stability of jojoba oil/water emulsion systems was investigated using the conductivity technique. Egg white, egg yolk, and bovine serum albumin (BSA) proteins were used as emulsifiers. Stability of above emulsions was investigated using several protein concentrations (0.05–0.50 mg/ml) and several oil volume fractions, OVF, (0.25; 0.50). It was concluded from the results that the investigated emulsions stability, when using BSA, was higher than when using egg white or egg yolk. In addition, emulsion stability did not show a strong dependence on OVF, except at the higher protein concentration of 5.0 mg/ml, where ES increased significantly with increasing OVF. Finally, emulsifier activity was found to increase with increasing OVF.

Possible influence of surfactants and proteins on the efficiency of contact agar microbiological surface sampling.

Agar contact microbiological sampling techniques, based on a transfer of the microorganisms present on a surface to a culture medium, are widely used to assess and control surface cleanliness and to evaluate microbial contamination levels. The effectiveness of these techniques depends on many environmental parameters that influence the strength of attachment of the bacteria to the surface. In the present study, stainless steel and high density polyethylene surfaces were inoculated with known concentrations of Staphylococcus epidermidis. Following an experimental design, the surfaces were sampled with different types of replicate organism direct agar contact plates and Petrifilm; results indicated that recovery rates were influenced by the presence of egg white albumin or Tween 80 in the inoculum solutions or by the introduction of surfactants into the contact agar of the microbiological sampling techniques. The techniques yielded significantly different results, depending on sampling conditions, underlining the need for a standardization of laboratory experiments to allow relevant comparisons of such techniques.

Infrared differential-absorption Mueller matrix spectroscopy and neural network-based data fusion for biological aerosol standoff detection

An active spectrophotopolarimeter sensor and support system were developed for a military/civilian defense feasibility study concerning the identification and standoff detection of biological aerosols. Plumes of warfare agent surrogates gamma-irradiated Bacillus subtilis and chicken egg white albumen (analytes), Arizona road dust (terrestrial interferent), water mist (atmospheric interferent), and talcum powders (experiment controls) were dispersed inside windowless chambers and interrogated by multiple CO(2) laser beams spanning 9.1-12.0 microm wavelengths (lambda). Molecular vibration and vibration-rotation activities by the subject analyte are fundamentally strong within this "fingerprint" middle infrared spectral region. Distinct polarization-modulations of incident irradiance and backscatter radiance of tuned beams generate the Mueller matrix (M) of subject aerosol. Strings of all 15 normalized elements {M(ij)(lambda)/M(11)(lambda)}, which completely describe physical and geometric attributes of the aerosol particles, are input fields for training hybrid Kohonen self-organizing map feed-forward artificial neural networks (ANNs). The properly trained and validated ANN model performs pattern recognition and type-classification tasks via internal mappings. A typical ANN that mathematically clusters analyte, interferent, and control aerosols with nil overlap of species is illustrated, including sensitivity analysis of performance.

Anti-inflammatory and anti-nociceptive effects of ethanolic extract of Setaria megaphylla leaves in rodents

The ethanolic leaf extract of Setaria megaphylla (100-300 mg/kg) wasinvestigated for pharmacological properties against egg white albumin - induced inflammation, Chemical as well as thermal- induced pain. The extractdemonstrated a dose – dependent anti- inflammatory and antinociceptiveactivities. These activities were comparable to that of ASA (100mg/kg). The leaf extract possess anti inflammatory and analgesic properties, which can beexploited in health care (Afr. J. Biomed. Res. 9: 229 – 233)Keywords: Setaria megaphylla, anti inflammatory, analgesic.

Effect on rebinding behavior with different composition and structure of the dually imprinted alginate polymer microspheres using proteins and o/w emulsion drops as dual templates

AbstractIn this study, the dually imprinted alginate polymer microspheres are prepared using proteins and o/w emulsion drops as dual templates with different structure and composition such as the content of hydroxylethyl cellulose (HEC), crosslinking degree, and porous size, etc. The rebinding tests are carried on egg white albumin (EA) protein imprinted alginate polymer microspheres with interpenetrating networks (IPNs) under various conditions like ionic strength, temperature, protein concentration, and pH value. Results showed that the IPNs with alginate and HEC by covalent bond influence the rigidity and swelling properties. Porous structure formed by introducing emulsion drops into alginate hydrogel has effect on the permeability and specific surface area of the polymer microspheres. The variation rule of rebinding behavior according to different HEC content and pore diameters reveals macromolecular imprinting effect to be different with pure pore creating effect compared with the emulsion imprinting effect. Moreover, the macromolecular and emulsion dually imprinting‐rebinding tests verify the co‐existing macromolecular imprinting effect and pore creating effect of emulsion imprinting. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010

Ultrasensitive chemiluminescent immunochemical identification and localization of protein components in painting cross-sections by microscope low-light imaging

The characterization and localization of proteins and other organic components in the complex stratigraphy of paintings is crucial for authentication and studies of painting techniques. With this aim we have developed a new ultrasensitive immunochemical procedure for the detection of the protein ovalbumin (chicken egg white albumin), present in binding media or varnishes, in painting cross-sections. The technique is based on chemiluminescence imaging detection combined with optical microscopy, and allowed the sensitive localization of the target protein in cross-sections with high spatial resolution. In order to evaluate its performance, the method was first applied to standard samples (also containing different common pigments), then used for the localization of ovalbumin in samples obtained from a Renaissance wood painting.

Synthesis of mesoporous carbon and its adsorption property to biomolecules

Mesoporous carbon (MC) with high surface area and large pore volume was synthesized using mesophase pitch as a carbon precursor and nanosized MgO as an additive. The maximum surface area, largest pore volume and highest mesoporous ratio of as-prepared MC were up to 1400 m 2/g, 2.8 cm 3/g and 89%, respectively. The mesoporous structures (3–40 nm) of MC were directly observed under SEM and TEM. The adsorption capacity and adsorption rate of MC to vitamin B 12 (VB), chicken egg white albumin (CEWA) and bovine serum albumin (BSA) were proportional to the mesopore volume and average pore size. MC (PM4-OC) exhibited the maximum adsorption capacity to the typical biomolecules, 486, 140 and 176 mg/g for VB, CEWA and BSA, respectively. In contrast, Maxsorbs (commercial activated carbons) with a surprising surface area gave a very low adsorption to such biomolecules. The research indicates that MC may be potential in the selective adsorption and separation of biomolecules, based on a molecule sieve effect.

Use of a 2,5-Dihydroxybenzoic Acid/Aniline MALDI Matrix for Improved Detection and On-Target Derivatization of Glycans: A Preliminary Report

N-Linked glycans derived from human and bovine alpha1-acid glycoprotein, as well as chicken egg white albumin, were analyzed by MALDI-TOF mass spectrometry using a novel MALDI matrix consisting of 2,5-dihydroxybenzoic acid (DHB) and aniline. A significant increase in signal was observed for these oligosaccharides relative to the signal obtained when unmodified DHB was used as a matrix for the same set of samples. The use of aniline/DHB matrix also led to facile on-target derivatization of the glycans via nonreductive amination, as aniline was found to form a stable Schiff base with the reducing end GlcNAc residue without the need for prolonged incubation periods and elevated temperatures. Both native and derivatized glycans ionized as sodium adducts and had similar MS/MS fragmentation patterns consisting mainly of Y/B-cleavage ions. In our experiments, we obtained evidence for persistence of the derivatization reaction in the solid phase; i.e., the reaction appeared to be taking place even after the sample-matrix spot had dried. This is the first report on such solid-phase on-target derivatization of carbohydrates for subsequent analysis by MALDI mass spectrometry.

Direct Identification of Tryptophan in a Mixture of Amino Acids by the Naked Eye

Seeing is believing: Treatment of tryptophan with formic acid and hydrochloric acid generates a violet-blue color. The reaction is very specific, and can be used to identify tryptophan in a mixture of amino acids, or corroborate the existence of tryptophyl groups in peptides or proteins (see picture; A: blank; B: a mixture of 9 representative amino acids; C: tryptophan; D: mixture (B) and tryptophan; E: reduced glutathione; F: egg-white albumin).

Macroporous hydrogels based on 2-hydroxyethyl methacrylate

Four series of macroporous hydrogels based on crosslinked copolymers of 2-hydroxyethyl methacrylate (HEMA)-sodium methacrylate (MANa), copolymer HEMA-[2-(methacryloyloxy)ethyl]trimethylammonium chloride (MOETACl), terpolymer HEMA-MANa-MOETACl and on a polyelectrolyte complex were used as carriers for immobilization of proteins, chicken egg white albumin and avidin. The adsorption capacity of the hydrogels for the two proteins, kinetics and pH dependence of albumin adsorption and desorption were studied. The morphology of the hydrogels with and without immobilized albumin was studied by low-vacuum scanning electron microscopy.

Adsorption Isotherms and Irreversible Binding of Proteins on Commercially Available Hydrophobic Adsorbents

Measurement of ascending and descending breakthrough curves of two proteins, hen egg white lysozyme and bovine serum albumin, on commercially available hydrophobic-interaction chromatographic columns reveal that only one part, i.e., the reversible adsorbed fraction, of the total bound amount can be desorbed by dilution of the feed solution. The other part is bound irreversibly; its binding behavior follows a hysteresis. Our procedure allows a clear separation of both parts. The reversibly adsorbed fraction of lysozyme can be represented with a Henry-type isotherm. For both proteins and for the reversible as well as the irreversible part, the adsorbed amount increases when the number of charges of the proteins decreases by approaching the isoelectric point.

Novel ELISA for the detection of raw and processed egg using extraction buffer containing a surfactant and a reducing agent

Enzyme-linked immunosorbent assay (ELISA) has been considered extremely useful for the detection of markers of allergenic substances in food, because it is simple, offers a suitable sensitivity, and is useful in providing quantitative results. Allergenic protein present in processed food can be denatured or altered, hindering therefore their possibility to be extracted and detected. This paper reports the development of an ELISA method that can be used for the determination of allergenic proteins in buffer solutions containing SDS, a surfactant, and 2-mercaptoethanol, a reducing agent. Measurement by ELISA in solutions containing 1% SDS and 7% 2-mercaptoethanol has been made possible by using an antibody prepared through immunization with an antigen denatured with SDS and 2-mercaptoethanol. This ELISA technique can be used to measure proteins in food that have been denatured by various manufacturing processes. An example is egg white albumin, which is susceptible to heat denaturation and has been difficult to recover from food in the past. Its recovery was improved 10- to 100-fold by the new ELISA method as compared with previous methods. This means that allergenic substances in food can now be detected quantitatively. This method can be very useful in allergy prevention and control strategies.

EFFECT OF ADDED SALT ON TEXTURAL PROPERTIES OF HEAT‐INDUCED GELS MADE FROM GUM–PROTEIN MIXTURES

ABSTRACT Large deformation rheological tests were employed to determine the textural differences in heat‐induced gel systems. Three different large deformation rheological methods (viscosity index and apparent elasticity, texture profile analysis (TPA) and torsional fracture) were employed to study the dependence of the ion type on the textural properties of heat‐induced mixed protein–gum gels. Protein–gum mixed solutions were prepared with bovine serum albumin (BSA) or egg white albumin (EWA) (20% w/v) with κ‐carrageenan (KCG), gellan (GLN) or xanthan gums (XNT) (0.5% w/v) at 0.1 M sodium chloride (NaCl), potassium chloride (KCl) or no added salt. Despite inherent differences in protein type, the main effect on the textural properties evaluated was for the kind of salt added, since potassium ions, with a strong influence on KCG and GLN gelation, affected the parameters related to the structure or hardness of the samples. There was no significant effect on parameters associated with sample ductility or elasticity. GLN formed stronger gels than KCG, whereas XNT did not perform as well in gel formation since it does not contribute to protein matrix formation. The results indicated that potassium may be substituted for sodium ions at low ionic strengths in foods where the incorporation of KCG or GLN helps to improve texture and related features.

Functionally‐modified egg white albumen hydrogels

AbstractHydrogels were prepared by using egg white albumen (EWA) before and after chemical modification of its lysyl residues with ethylenediamine tetraacetic dianhydride (EDTAD) to incorporate carboxylic groups. This resulted in an increase in swelling ratio of the EWA hydrogels. The swelling ratio increased dramatically in deionized water substantially, more than in pH 7.4 buffer solution. The effects of medium pH, temperature and swelling were investigated, along with crosslinking of the gel network by glutaraldehyde (GLA), as well as acetone treatment. The gels denatured by acetone showed an insignificant increase in swelling ratio for the gels crosslinked with GLA during gel preparation, which is in contrast to the gels crosslinked subsequent to gel formation. The swelling behavior was positively affected by temperature and time. However, an insignificant effect of pH was observed due to electrostatic screening of the carboxylic groups by sodium ions in the buffer solution. Availability of various functional groups on EWA has resulted in adsorption of metals (Cu+2 ions) and non‐metals (PO4−2 anions). Copyright © 2004 Society of Chemical Industry

Adsorption of rye pollen and egg-white allergens on aerosil

The surface of aerosils – substances representing highly disperse nontoxic silica gels – is characterized by a very large area and a specific morphology. These factors account for the high adsorption capacity of aerosils with respect to proteins, enzymes, exoand endotoxins, and microorganisms. The absence of developed pores ensures a high rate of adsorption on the aerosil surface, which makes these media promising sorbents and carriers for immobilization of a wide spectrum of biologically active substances [1]. Sorption methods are used in the course of specific immunotherapy for the immobilization of allergens. Adsorbents used for such purposes include both inorganic (calcium phosphate [2, 3], aluminum hydroxide and phosphate [4]) and organic (L-tyrosine [5]) media; it was also suggested to use activated charcoal as a metric for diagnostic purposes [3]. The aim of this work was to study the process of immobilization of some pollen and food-born allergens on aerosil. We have studied the properties of A-380 aerosil, which had never been used before as a medium for allergen immobilization. This sorbent, obtained from the Institute of Surface Chemistry (National Academy of Sciences of Ukraine, Kiev), is a highly disperse nonporous silica gel with a specific surface of 380 m g, an average particle size of 7 nm, and a surface concentration of silicon atoms of 5.09 mmole g. The main adsorption centers on the aerosil surface are silanol groups (SiOH2 ). The experiments were performed with commercial preparations of rye pollen allergen (RPA) and egg-white allergen (EWA) in the form of aqueous-salt solutions obtained from the “Immunolog” Company (Vinnitsy), which were standardized with respect to protein nitrogen (PNU cm) and stabilized with 0.4% of phenol. RPA and EWA are representatives of the wide classes of pollen and food-born allergens, which are used both for diagnostic purposes and for specific immunotherapy [6, 7] in the complex treatment of allergic disorders. These agents are widespread and characterized by high allergen activity. As is known, the main allergen components in both rye pollen (molecular weight, 38 – 40,000) and in egg-white albumin are glycoproteins (lysozyme, ovalbumin, avomucoid). We have studied the dependence of the allergen adsorption on the protein carrier ratio and the time. The content of

Effect of Starch and Egg White Albumin on the Textural and Cooking Properties of Restructured Squid Patties (Illex illecebrosus)

Restructured squid patties were produced from the underutilized species of North Atlantic short-finned squid (Illex illecebrosus) with selected heat-set binders (starch and egg white albumin). The effects of type and level of each heat-set binder, as well as their combinations, were evaluated for their textural and cooking properties. The levels of each heat-set binder ranged from 2, 4, 6, 8, to 10%. When the level of starch was increased from 2 to 10%, a decrease in hardness, co-hesiveness, and springiness was observed. However, 2% egg white albumin increased the hardness and cohesiveness. When starch was combined with egg white albumin to the combined level of 10%, all textural parameters decreased. In general, starch had no ability to improve cohesiveness as an index of gel strength when combined with egg white albumin. However, starch-based combinations were able to lower the cooking loss of restructured squid when compared to those produced from starch and egg white albumin separately.