Characterization of Chicken Skin Collagen Using Liquid Chromatography-Mass Spectrometry (LCMS) and SDS-Polyacrylamide Gel Electrophoresis (SDS-PAGE)

Collagen extraction from animal processing wastes has increasingly been of interest due to the abundance of collagen in by-products.Collagen is used extensively in the health care, food and beverage, and cosmetic industries, which has increased the need for alternative collagen sources.The extraction of collagen from chicken by-product creates effective use of underutilized resources and a low-cost production of collagen.The objective of this research was to analyze chicken collagen and compare the characteristics with bovine type I collagen to identify possible methods to use chicken collagen as an alternate source.Chicken skins were obtained from the Frostburg State University cafeteria and pretreated with 0.1N NaOH, 10% butyl alcohol, and 0.1N HCl in the microbiology lab to remove noncollagenous protein, fat, and inorganic material, respectively.Collagen was extracted with 0.5M acetic acid containing pepsin (2g/100g) and precipitated with a 2.6M NaCl solution that had 0.05M tris hydroxymethyl aminomethane.The collagen extract was centrifuged at 20,000g at 4°C for one hour.The precipitate was salted out with 0.5M acetic acid before being dialyzed against distilled water.Collagen extracted from acetic acid and with pepsin from the chicken skin provided the highest collagen yield with P <0.05 for the level of significance.The LC-MS results indicated that the mass spectra for major correlated peaks were similar for chicken skin collagen and bovine type I collagen with similar retention times.The LC-MS results suggested that chicken collagen and bovine collagen type I have similar chemical compositions.The SDS-PAGE page results also confirmed that the chicken skin and bovine type I collagen have similar banding patterns with α-1 and α-2 chains that have 148 kD and 130 kD molecular weights, respectively.These results indicated that the chicken skin collagen was a type I collagen and can be used as an alternate collagen source.