Extraction of low molecular weight peptides from bovine bone using ultrasound-assisted double enzyme hydrolysis: Impact on the antioxidant activities of the extracted peptides

In this study, we developed an ultrasound-assisted double enzyme hydrolysis method for the extraction of low molecular weight peptides (LMWP) from bovine bone and determined the optimal process using response surface methodology (RSM). Moreover, we have discussed the effect of the extraction methods on the structure and antioxidant properties of bovine bone peptides (BBPs). Results from RSM studies showed that the optimal extraction yield of 21.04% was obtained when the experimental parameters were 76.25 × 10 4 U/g of the enzyme addition, an ultrasonic power of 413.90 W/L, pH of 9.00, and ultrasonic time of 2.01 h. The BBPs obtained using ultrasound-assisted enzyme hydrolysis (UDE) were appeared as small granules, uniform in structure, and exhibited a rough surface. Moreover, the BBP was found to have obvious amide I, II, and III band structures and an increase in hydrogen bonding, as determined using FTIR and NMR. In addition, the peptide extracted using UDE had the optimal antioxidant effect ( P  < 0.05). Thus, UDE is an efficient method for the extraction of LMWPs from bovine bone. This method can be used in an industrial extraction of bone peptides as it can have a positive effect on resource re-utilization of bovine bone.