Physicochemical Properties of Collagen from the Bone of Harpadon nehereus and Its Protective Effects against Angiotensin II-Induced Injury in Human Umbilical Vein Endothelial Cells

[Image: see text] The physicochemical characterization of a new collagen from the bone of Harpadon nehereus (HNBC) and its protective effects against Ang II-induced injury of human umbilical vein endothelial cells (HUVEC) were investigated. The triple helix of HNBC analyzed by SDS-PAGE was formed as (α(1))(2)α(2), belonging to type I collagen. UV spectra showed that HNBC had a maximum absorbance at 230 nm. FTIR spectra indicated the triple helical structure and activity of HNBC. The high solubility of HNBC was observed in the low pH ranges (≤4) and NaCl concentrations (≤2%, w/v). The maximum transition (T(m)) of HNBC was determined to be 48.5 °C. The amino acid composition analysis showed that glycine, glutamic acid, proline, and alanine were the abundant amino acids available in HNBC. HNBC showed free radical (DPPH and OH·) scavenging activities in the tested concentrations (0.5–6 mg/mL). In addition, HNBC could effectively protect against Ang II-induced injury of HUVEC by increasing the activities of antioxidant enzymes, such as CAT, SOD, and GSH-Px. Overall, collagen from the bone of H. nehereus has promising prospects in functional food and biomedical industries.