title: Optimization of enzyme-assisted extraction and characterization of collagen from Chinese sturgeon (Acipenser sturio Linnaeus) skin.
abstract: BACKGROUND
  Sturgeon (Acipenser sturio Linnaeus) skin contains high amount of nutrients including unsaturated fatty acids and collagen. A pepsin-assisted extraction procedure was developed and optimized for the extraction of collagen from Chinese sturgeon (Acipenser sturio Linnaeus) skins.
  
  
  OBJECTIVE
  To determine the optimum conditions with the maximum yield of the pepsin-soluble collagen (PSC) extraction.
  
  
  METHODS
  The conditions of the extraction were optimized using response surface methodology. The Box-Behnken design was used to evaluate the effects of the three independent variables (extraction time, enzyme concentration, and solid-liquid ratio) on the PSC yield of the sturgeon skin.
  
  
  RESULTS
  THE OPTIMAL CONDITIONS WERE: solid-liquid ratio of 1:11.88, enzyme concentration of 2.42%, and extraction time of 6.45 h. The maximum yield of 86.69% of PSC was obtained under the optimal conditions. This value was not significantly different from the predicted value (87.4%) of the RSM (P < 0.05).
  
  
  CONCLUSIONS
  The results of this study indicated that the production of PSC from sturgeon skin is feasible and beneficial. The patterns of sodium dodecyl sulfate-polyacrylamide gel electrophoretic patterns (SDS-PAGE) indicated that the sturgeon skin contains type I collagen, which is made of α-chain and β-chain. The infrared spectra of the collagens also indicated that pepsin hydrolysis does not affect the secondary structure of collagen, especially triple-helical structure.
authors.affiliation: School of Food and Biological Engineering, Jiangsu University, 301 Xuefu Rd., 212013 Zhenjiang, Jiangsu, China.
authors.forename: Weiwei
authors.initials: W
authors.lastname: Feng
authors.forename: Ting
authors.initials: T
authors.lastname: Zhao
authors.forename: Ye
authors.initials: Y
authors.lastname: Zhou
authors.forename: Fang
authors.initials: F
authors.lastname: Li
authors.forename: Ye
authors.initials: Y
authors.lastname: Zou
authors.forename: Shiqi
authors.initials: S
authors.lastname: Bai
authors.forename: Wei
authors.initials: W
authors.lastname: Wang
authors.forename: Liuqing
authors.initials: L
authors.lastname: Yang
authors.forename: Xiangyang
authors.initials: X
authors.lastname: Wu
keywords: Extraction; SDS-PAGE; pepsin-soluble collagen; response surface methodology; sturgeon skin