High-intensity ultrasound enhances the immunoglobulin (Ig)G and IgE binding of ovalbumin.

BACKGROUND: Hen eggs are widely used in food industry as a result of their excellent nutritional and processing properties and ovalbumin (OVA) is the major allergen of hen egg whites. Ultrasound has been widely used in the food processing industry, although the effect of high-intensity ultrasound on the immunoglobulin (Ig)G binding, IgE binding and conformational structure of OVA remains unclear.

RESULTS: Ultrasound treatment at 600-800 W dramatically increased the IgG and IgE binding of OVA, with the highest values observed at 600 W. The free sulfhydryl content, surface hydrophobicity and ultraviolet absorption were gradually increased when the power was increased from 200 to 600 W, implying the occurrence of molecule unfolding. When the power was 800 W, the binding ability was slightly decreased and was associated with the aggregation of OVA molecules. Polyacrylamide gel electrophoresis analysis implied that ultrasound treatment at 800 W could induce the aggregation of OVA molecules via disulfide bonds and/or hydrophobic interactions.

CONCLUSION: High-intensity ultrasound can increase the potential allergenicity of OVA. Therefore, high-intensity ultrasound processing of some egg products alone may improve the risk of an allergenic reaction in egg allergy patients to some extent. © 2016 Society of Chemical Industry.