鮟鱇鱼皮中胶原蛋白的提取及性质研究

Extraction and Characterization of Collagen from Anglerfish (Lophius Litulon) Skin

采用0.5mol/L醋酸提取,结合NaCl沉淀法从鮟鱇鱼皮中提取酸溶性胶原蛋白(ASC),并对鮟鱇鱼皮胶原蛋白与Sigma公司的牛跟腱Ⅰ型胶原蛋白(BATC)进行比较,探讨二者在热变性温度、溶解度、黏度及氨基酸组成等方面的差异。SDS-PAGE结果显示ASC有2条α链(α1和α2链)、β链和γ链,表明该胶原为典型的Ⅰ型胶原蛋白。DSC分析显示两种胶原的热变性温度分别为22.09℃和38.13℃。氨基酸组成分析结果是亚氨基酸含量ASC低于BATC,分别为14.69%和21.59%;甘氨酸含量相近,分别占所有氨基酸总数的40.05%和38.97%。溶解度结果显示ASC和BATC分别在pH3和pH4时达到最大值,在pH7时两者都呈现最小溶解度;NaCl含量对两者溶解度的影响相同,当其含量低于2%时对溶解度的影响不明显,而随着NaCl含量的增加,溶解度迅速下降。

Acid-soluble collagen（ASC） was extracted from the skins of anglerfish（Lophius americanus） using 0.5 mol/L acetic acid and precipitation with 0.9 mol/L NaCl,The anglerfish ASC and type 1 collagen（Bovien archilles tendon collagen,BATC） of Sigma company were comparatively studied in denaturation temperature,solubility,viscosity and amino acid composition.The ASC yields,on a dry weight basis,were 35.5%.SDS-PAGE showed that the collagens contained two alpha components（α1 and α2）,β and γ chains,then this ASC was classified as type 1 collagen.The denaturation temperature of ASC and BATC were determined to be 22.09℃ and 38.13℃ respectively,by DSC.Amino acid analysis showed that imino acid content of ASC was much lower than BATC,which was 14.69% and 21.59% respectively,meanwhile the glycine content was similar,to be 40.05% and 38.97% of total amino acids.ASC and BATC had the highest solubility at pH 3 and 4,and both have the lowest solubility at pH 7.No obvious changes in solubility of two collagens were observed in the presence of NaCl at 0～2%,a rapid decrease in solubility was observed above 2%.