Immunoglobulins: Structure, Function, and Applications in Functional Foods-a review

Immunoglobulins, a class of glycoproteins with antibody activity, are abundant in bovine colostrum and constitute nutritionally significant functional components in the food industry. The immunoglobulin family encompasses five subclasses: IgG, IgM, IgA, IgD, and IgE, each of which mediates pathogen neutralization, opsonization, complement activation, and mucosal immune defence mechanisms. Despite their substantial health-promoting potential, translating immunoglobulins into functional food products remains challenging. Key obstacles include maintaining bioactivity during food processing, uncertainties regarding oral bioavailability, and a lack of comprehensive regulatory standards. This review systematically examines the molecular conformations, domain-specific features, and complex glycosylation patterns of immunoglobulin Fc regions. It also discusses their immunological mechanisms and structure–activity relationships, evaluates the current applications and functionalities of immunoglobulins in functional foods, and summarizes outstanding research issues and future directions. Collectively, these insights provide a comprehensive reference for further investigation and development of immunoglobulin-based food products.