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Bonding agents
Published in Jill L. Baker, Technology of the Ancient Near East, 2018
Glue made from birds’ eggs, came mostly from waterfowl such as duck and geese and from chickens in later periods (Newman and Serpico 2009:475, 485; Lucas and Harris 2011:1–2). The egg white, the egg yolk, or the two of them combined could serve as binders. Each component of the egg contains proteins, albumen, and ovalbumin, all of which can function as adhesives. The white and yolk were used together or separately, depending on the type of binding desired. Egg white could be dried and mixed into a solution or whipped and used unaided. The yolk was also whipped, but it had to be used immediately because dried yolk could not be reconstituted. The presence of egg as a bonding agent can be determined by amino acid analysis; however, this type of analysis cannot distinguish between white and yolk since the same lipids and triglycerides are present (Newman and Serpico 2009:475, 485; Lucas and Harris 2011:1–2). Egg was frequently mixed with paint or applied to paintings as a stabilizer. This method has been detected in the Twelfth Dynasty tomb of Kahun, the Eighteenth Dynasty paintings at Tell el Amarna (Lucas and Harris 2011:1), on the paintings in the tomb of Nefertari (QV66), and as a coating or varnish, especially over red and yellow paint (Newman and Serpico 2009:485).
Adhesive Biomaterials for Tissue Repair and Reconstruction
Published in Severian Dumitriu, Valentin Popa, Polymeric Biomaterials, 2020
The concept of using an adhesive to join or rejoin tissues dates back to at least 1787, when it was noted that “many workmen glue their wounds with solid glue dissolved in water” [8]. The use of hide glue (similar to gelatin, which is itself derived from collagen protein) was most common, but other biological adhesives such as blood and egg white (albumin) have also been used for centuries. However, the search for the perfect operative sealant continues, as an ideal tissue adhesive must overcome difficult performance challenges.
Advances in Nanotechnology of Food Materials for Food and Non-Food Applications
Published in Dennis R. Heldman, Daryl B. Lund, Cristina M. Sabliov, Handbook of Food Engineering, 2018
Rohollah Sadeghi, Thanida Chuacharoen, Cristina M. Sabliov, Carmen I. Moraru, Mahsan Karimi, Jozef L. Kokini
Ovalbumin (OVA) is the most abundant protein in egg white. It is a glycoprotein that comprises 54% of the total proteins of egg white, and its molecular weight is 45 kDa. The sequence includes six cysteine units; four of them are sulfhydryl groups (SH) and two of them (Cys74 and Cys121) are attached to each other as a single disulfide bond (S-S). During OVA unfolding, such as caused by heat denaturation, SH groups can be superficially exposed and interact with each other. This phenomenon is responsible for the aggregation of OVA molecules under heat denaturation. Addition of a desolvating agent to ovalbumin solution leads to precipitation of some parts of dissolved protein molecules, which has not been observed for other albumins like alpha-lactalbumin and bovine serum albumin. Etorki et al. (2016) reported the ability of OVA to prepare nanoparticles using desolvation method and centrifugation to remove large aggregates. Table 2.3 shows the effect of three desolvating agents and the desolvating agent to protein solution ratios on the particle size, polydispersity index, and zeta potential of ovalbumin NPs. It is possible to prepare sub-100 nm OVA nanoparticles which can be effectively used for food and drug formulations. Most of the reported nanoparticles from natural products, and for proteins, are larger than 100 nm. Both ethanol and methanol produce NPs in the range of 60–80 nm, and the smallest nanoparticles are prepared by using methanol as the desolvating agent. There is no significant difference in particle size between different ratios of the three desolvating agents; the polydispersity index for 1:3 ratio is the highest for the three desolvating agents. Polydispersity of ovalbumin NPs for ethanol and acetone is between 0.2 and 0.3, which is acceptable for biocompatible NPs while it’s very high compared to BSA and AL. This clearly shows that even different albumins with the same solubility range show different nanoparticulation profiles depending on their sequence, conformation, and chemistry. SEM images show the size distribution and morphology of small NPs from OVA by desolvation method and cent rifugation using ethanol as the desolvating agent (Etorki et al., 2016) (Figure 2.7).
Complex coacervation of carboxymethyl konjac glucomannan and ovalbumin and coacervate characterization
Published in Journal of Dispersion Science and Technology, 2022
Ya-Qian Cao, Guo-Qing Huang, Xiao-Dan Li, Li-Ping Guo, Jun-Xia Xiao
Ovalbumin (OVA) is a glycoprotein and accounts for 54% to 69% of the total egg white protein. It possesses an isoelectric point of around pH 4.5 and has been extensively used as an amphoteric electrolyte to coacervate with various biopolymers.[11,12] In this work, OVA was selected as a model to investigate the electrostatic interaction of CMKGM with proteins. The conditions for the maximum interaction between the two polyelectrolytes were optimized and the physiochemical properties of the resultant coacervates were characterized. We believe that this work could provide valuable information regarding the interaction of CMKGM with proteins and promote the application of CMKGM in the preparation of polyelectrolyte complexes and the construction of colon-targeted delivery systems through the electrostatic interaction with other oppositely charged polyelectrolytes.
Conductive hydro drying as an alternative method for egg white powder production
Published in Drying Technology, 2020
R. Preethi, D. Shweta, J. A. Moses, C. Anandharamakrishnan
Egg white is valued for its proteins and its unique functional property. Generally, egg white is used as a foaming agent and emulsifying agent in the food industry.[41] Reportedly, globulins in egg white are an essential component responsible for foam formation, and ovomucin confers the stability of the foam.[6] The foaming behavior of egg white powder dried under different methods is shown in Figure 4a. All samples exhibited good foaming characteristics. Foaming ability and foam stability were higher in the case of egg powders dried using CHD and FD as compared to SD egg white powders. Interestingly, foam height was higher in the case of CHD powder as compared to SD and FD powders. Foam stability was evaluated, and it was observed to be constant for 30 min in the case of CHD and FD samples; however, the foam collapsed in the case of SD samples. This result showed the effectiveness of CHD drying of egg white without affecting its foaming behavior. The presence of higher levels of proteins could have resulted in denser and stable foams due to the strong interfacial films developed in the foam.
Ovalbumin-mediated synthesis and simultaneous functionalization of graphene with increased protein stability
Published in Green Chemistry Letters and Reviews, 2020
Riaz Ullah, Shadab Ali Khan, Aref Ali Mohammed Aladresi, Sulaiman Ali Alharbi, Arunachalam Chinnathambi
Chicken egg albumin (ovalbumin), a phosphorylated glycoprotein, constitutes the major part of egg white. It has a molecular weight of 45 kDa and possesses 385 amino acid residues (24). Ovalbumin can be used as a carrier protein to conjugate to synthetic peptides for use as an immunogen. It contains 20 Lys, 10 Tyr, 6 Cys, 14 Asp, and 33 Glu amino acid residues, which makes it suitable for conjugation on substrates.