Rat OVA sIgG(Ovalbumin specific Immunoglobulin G) ELISA Kit

Carvacrol is an effective natural antimicrobial and antioxidant agent; however, its poor aqueous solubility and high volatility limit its application in food systems. Ovalbumin can encapsulate hydrophobic molecules, thereby improving aqueous solubility and reducing volatility. The aim of this study was to explore the potential of an ovalbumin nanocarrier to improve the application range of carvacrol. Protein structure and scanning electron microscopy showed that carvacrol increased gel hardness and tackiness at pH 5, and OVA gel formed a uniform granular shape that was beneficial for reconstitution. The dominant force in OVA gel changed from electrostatic to hydrophobic interaction, indicating that carvacrol could hydrophobically bind to the gel. The ovalbumin-carvacrol (OVA-Car) complex was prepared using an oil-in-water method. The particle size was 132 +/- 10 nm, and the encapsulation efficiency was 51.41%. The polydispersity index was 0.355, indicating the general stability of the composite. Fluorescence spectroscopy and differential thermogram studies indicated complex formation. Antibacterial property testing against Bacillus cereus and Salmonella indicated that the OVA-Car complex inhibited bacterial growth at lower concentrations than free carvacrol. Minimum inhibitory concentration and minimum bactericidal concentration for Bacillus cereus (0.0968 and 0.3875 mg/mL) and Salmonella (0.1937 and 0.3875 mg/mL), respectively, were 2-4 times higher than those of free carvacrol. The time sterilization curve indicated that pathogenic bacterial growth did not reach the control level. The OVA-Car complex has potential application in food systems owing to its storage stability and improved antimicrobial activity.

Animal proteins are widely used because of their good techno-functional (e.g. emulsification) properties. However, the large ecological impact of animal-derived proteins is often debated and therefore alternatives are evaluated in which animal proteins with increased functionality are employed. Amyloid fibrils are a distinct type of protein fibrils characterized by an intermolecular cross beta-sheet structure, mostly studied because of concerns regarding their role in certain human diseases. However, they have also been detected in processed food proteins such as heated ovalbumin (OVA) and other egg proteins. Previous work also mentioned superior emulsification properties of amyloid-like fibrils. Here, the effect of different shear conditions during the emulsification of oil in water emulsions stabilized by heated OVA was investigated. Emulsification with intensive shear treatment (using both an ultra-turrax and a microfluidizer) resulted in submicron sized droplets, whilst ultra-turrax only gave rise to rapidly creaming emulsions (>10 mu m). Thioflavin T (ThT) fluorescence, used as an indicator of cross beta-sheets, did significantly increase for submicron emulsions, whereas supermicron emulsions showed a similar fluorescence as the aqueous phase used for emulsification. The increase in ThT fluorescence in submicron emulsions was in line with a higher amount of larger fibrillar structures, which showed high ThT fluorescence, measured using size exclusion-HPLC and transmission electron microscopy images. Similar observations were also made for unheated OVA, suggesting that high-shear emulsification induced amyloid-like fibril formation. In contrast, shearing of aqueous solutions without the creation of interfaces did not show increased fibril formation. Therefore, it is claimed that the large specific surface area induced amyloid-like fibril formation or maturation as a result of a better interaction between hydrophobic amyloid-like fibril fragments. In this work, we were able to characterize the protein fibrillar structures present in emulsions by considering commonly used techniques for the study of fibril formation. This creates opportunities towards the implementation of these protein mixtures in food applications.