Characterization and Immunomodulatory Activity of a Novel Peptide, ECFSTA, from Wheat Germ Globulin

A novel peptide was extracted from wheat germ globulin and purified using ion-exchange chromatography, gel filtration chromatography, and semi-preparative reversed-phase high-performance liquid chromatography (RP-HPLC). The sequence of the peptide was found to be Glu-Cys-Phe-Ser-Thr-Ala (ECFSTA). Its immunomodulatory effects were evaluated, and the results showed that ECFSTA could enhance phagocytosis of RAW 264.7 cells and significantly increase their secretion of nitric oxide (NO), interleukin 6 (IL-6), tumor necrosis factor α (TNF-α), and reactive oxygen species (ROS). ECFSTA activated macrophages mainly through the pattern recognition receptors (PRRs) of toll-like receptor 2 (TLR2) and toll-like receptor 4 (TLR4), and the production of ROS simultaneously stimulated macrophages to produce TNF-α. Thus, ECFSTA could be used as an immunomodulator and might be a promising component of functional foods.