Abstract: Ovotransferrin (OVT) is a functional iron-binding egg protein with abundant nutritional value and a wide range of functional properties, which can be applied in a variety of food systems. Moreover, it is an ideal alternative to lactoferrin. The structure and physicochemical properties of OVT affect the performance of egg white in food processing, and the changes in its physicochemical properties are usually related to structural changes. This article reviews various purification and separation methods for OVT. The iron-binding sites and the mechanism of iron release are explained by comparing the tertiary structures of the apo and holo forms of OVT, and the phosphorylation and glycosylation modification sites of OVT are summarized. The relationship between physicochemical properties of OVT and its structural changes is discussed. Various biological activities of OVT and its application in the food and medical industries are described. In addition to being used as a natural food preservative, immunomodulator, and functional food ingredient beneficial to human health, OVT also shows great potential in preparing food-grade carriers to improve the bioavailability of nutritional and active ingredients. Finally, the challenges and future directions of OVT research are provided.

Key words: ovotransferrin, isolation and purification, structural properties, biological activity