Impact of ultrasound-assisted extraction on the functional and structural properties, digestibility, hypoglycemic and lipid-lowering effects of seabuckthorn seed meal glutelin

Seabuckthorn seed meal (SSM) is a protein-rich by-product of the oil extraction industry. This study investigated the effects of ultrasound-assisted extraction (UAE) on the physicochemical and functional properties, in vitro digestibility, as well as hypoglycemic and lipid-lowering activities of SSM glutelin. Results indicated that SSM glutelin extracted with UAE (USBG) exhibited higher extraction yield and protein content than SSM glutelin extracted without ultrasound (SBG). Additionally, UAE increased amino acid content, loosened the protein structure, reduced particle size, altered the secondary and tertiary structures of USBG. Moreover, USBG demonstrated enhanced functional properties, like solubility, water-holding and oil-holding capacity, thermal stability, and so on. UAE also improved the in vitro digestibility of USBG, while decreasing the particle size and increasing amino content after digestion. Furthermore, USBG exhibited enhanced hypoglycemic and lipid-lowering activities. Therefore, UAE significantly improves the structure, functionality, digestibility and bioactivities of SSM glutelin, thereby adding value to seabuckthorn by-products.