The preparation of bone peptides (livestock and poultry bone peptides, LBPs) for the development of bone-derived functional foods is one of the important ways for the high-value utilization of livestock and poultry bone by-products. In this experiment, the leg bone from four main livestock and poultry species were used as raw materials to prepare LBPs based on the same process, and their physicochemical properties and bioactivities were compared and analyzed, so as to provide the reference for the high-value utilization of livestock and poultry bone resources and the development of bone-derived functional foods.
Yak bone peptides (YBPs), bovine bone peptides (BBPs), porcine bone peptides (PBPs) and chicken bone peptides (CBPs) were prepared from yak, bovine, porcine and chicken leg bones, respectively. Physicochemical properties were characterized, including basic nutritional components, amino acid compositions, molecular weight and particle size distribution. Moreover, the bioactivities of the four LBPs, including osteoblast promoting proliferation, immune regulation, angiotensin converting enzyme inhibitors (ACEI) and antioxidation, were compared and analyzed.
The relative contents of crude protein in YBPs, BBPs and PBPs were (89.70±0.77)%, (90.43±0.88)% and (89.36±1.32)%, respectively, which were significant higher than that of CBPs (79.18±1.49)%). The essential amino acids and sulfur-amino acids of CBPs were significant higher than those of YBPs, BBPs and PBPs. The four LBPs were mainly composed of small molecular peptides with MW<2 kD, accounting for about 90%. There was no significant difference in particle size distribution of LBPs powder, which was mainly concentrated in the range of 10-20 µm and 40-60 µm. The bioactivities of different LBPs were analyzed. It was found that YBPs had the most significant osteoblasts promoting proliferation effect, and the proliferation rate was 37.27% at 0.5 mg∙mL-1; BBPs had the strongest effect on macrophage proliferation, and the proliferation rate was 39.26% at 5 mg∙mL-1; PBPs had the strongest ACEI activity, and the inhibition rate of ACE activity was 82.37% at 15 mg∙mL-1; YBPs had the strongest comprehensive antioxidant capacity, compared with BBPs, PBPs and CBPs.
The physicochemical properties of LBPs from four distinct species were different, but they all met the demand of raw material for the development of bone-derived functional foods. The bioactivities of LBPs from different species were different, which were suitable for the development of different bone-derived functional foods: YBPs had the strongest osteoblasts promoting proliferation effect and comprehensive antioxidant capacity, which was more suitable for the development of bone health improving or antioxidant bone-derived functional foods; BBPs had the strongest effect on promoting macrophage proliferation, which was more suitable for the development of immunomodulatory bone-derived functional foods; PBPs had the strongest ACEI activity and was more suitable for the development of bone-derived functional foods with blood pressure control effect; CBPs had the better powder properties and higher mineral content, which could be used as dietary nutritional supplements.