An alternative source of type I collagen based on by-product with higher thermal stability

Acid-soluble collagen (ASC) and pepsin-soluble collagen (PSC) were isolated from quails' feet and characterized. The electrophoretic patterns indicated that the collagens are composed of alpha 1, alpha 2, beta and gamma-chains, corresponding to the properties of collagen type I. One major characteristic of the obtained collagens is that they were found to have high thermal stability. The denaturation temperature (T-d) and maximum transition temperature (T-max) of ASC (39.6 and 110.7 degrees C) and PSC (3833 and 109 degrees C) assessed using the differential scanning calorimetry and rheometer. These results could be attributed to the high imino acid content of ASC and PSC (248.72 and 224.17 residues/1000 residues) and degree of pro hydroxylation (45.91% and 45.44%), respectively. Both ASC and PSC can assemble into collagen fibrils. The D-periodicities of fibrils assembled from PSC (70.6) were slightly smaller than those of fibrils assembled from ASC (72.9). Summarizing the experimental results suggested that the extracted collagens from quails' feet with high thermal stability could be considered an alternative to mammalian-derived collagen in biomaterials, functional foods, pharmaceuticals and cosmetics. (C) 2016 Elsevier Ltd. All rights reserved.