Isolation and characterization of collagen from the cartilage of Amur sturgeon (Acipenser schrenckii)

The collagen in Amur sturgeon cartilage was isolated using sodium chloride (salt-solubilized collagen, SSC, 2.18%), followed by acetic acid (acid-solubilized collagen, ASC, 27.04%) and then pepsin (pepsinsol ubilized collagen, PSC, 55.92%). These collagens appeared to be dense sheet-like film linked by randomcoiled filaments under SEM. The denaturation and melting temperatures of PSC (35.71 and 123.90 degrees C) were significantly higher than SSC (32.64 and 114.51 degrees C) and ASC (32.98 and 120.72 degrees C) assessed by circular dichroism and differential scanning calorimetry, which could be attributed to its high imino acid content (22.57%) and degree of hydroxylation (47.29%). Electrophoresis pattern showed that the SSC and ASC were type I collagen, while PSC was predominantly type II collagen along with other minor types. Infrared spectra confirmed their triple helical structure, and indicated more hydrogen bonding in ASC and more intermolecular crosslinks in PSC. These results provide some basis for their large-scale production and further application as alternatives to mammalian collagen. (c) 2013 Elsevier Ltd. All rights reserved.