Wheat bran arabinoxylan and bovine serum albumin conjugates: Enzymatic synthesis, characterization, and applications in O/W emulsions

Wheat bran arabinoxylan-bovine serum albumin (WBAX-BSA) conjugates were prepared via enzymatic synthesis using horseradish peroxidase (HRP) and H2O2 as catalysts. The conjugates were characterized by ultraviolet–visible spectroscopy (UV–vis), high-performance size exclusion chromatography (HPSEC), scanning electron microscopy (SEM), and transmission electron microscope (TEM). The feasibility of its application in stable emulsions was also assessed. UV–vis results revealed that phenolic acid in WBAX and aromatic amino acids in BSA were implicated in the enzymatic synthesis of the WBAX-BSA conjugate with the optimal WBAX:BSA mass ratio of 3:2. HPSEC results confirmed the intermolecular interactions between WBAX and BSA and the molecular weight of WBAX-BSA (2673 ± 16 kg/mol) was higher than that of control groups. Compared with the WBAX/BSA physical complexes, the WBAX-BSA conjugates had higher apparent viscosity (0.08–0.24 Pa.s), denser structure, larger particle sizes (33.5 ± 5.7 nm), and improving emulsifying properties in oil in water (O/W) emulsion system under different environmental stresses. The preparation of the enzymatic conjugates not only provides novel O/W emulsion systems but also improves processed food manufacturing processes that require efficient emulsification.