title: Preparation and dynamic viscoelasticity characterization of alkali-solubilized collagen from shark skin.
abstract: Alkali-solubilized collagens, prepared by alkali-acid extraction and alkali direct extraction (abbreviated AASC and ALSC, respectively), were characterized by dynamic viscoelastic measurement of collagen solution (10 mg/mL). The optimum preparative conditions in terms of yield and polypeptide size are as follows: for the alkali-acid extraction, a pretreatment with 0.5 or 1 M NaOH containing 15% Na(2)SO(4) within 5 days at 20 degrees C followed by the subsequent acid extraction, and for the alkaline direct extraction, a treatment with 0.5 M NaOH containing 10% NaCl at 4 degrees C for 20-30 days. A major portion of the polypeptide sizes of AASC and ALSC is composed of alpha chains (alpha1 and alpha2). Dynamic viscoelasticity of collagen solution was measured as a function of temperature. AASC showed a greater contribution of elastic behavior rather than viscous behavior. On the contrary, ALSC exhibits a stronger viscous behavior than elastic behavior.
authors.affiliation: Tokyo Metropolitan Leather Technology Center, 3-3-14, Higashisumida, Sumida-ku, Tokyo 131-0042, Japan. mu2k-ysmr@asahi-net.or.jp
authors.forename: K
authors.initials: K
authors.lastname: Yoshimura
authors.forename: M
authors.initials: M
authors.lastname: Terashima
authors.forename: D
authors.initials: D
authors.lastname: Hozan
authors.forename: K
authors.initials: K
authors.lastname: Shirai
mesh_terms: D000818:Animals; D003094:Collagen / Q000737:chemistry*; D004548:Elasticity; D012754:Sharks; D012867:Skin / Q000737:chemistry*; D014783:Viscosity
chemical_list: D003094:Collagen