鲟鱼软骨中II型胶原蛋白的提取及其结构鉴定

Extraction and structural identification of collagen type II from sturgeon cartilage

中文关键词:  鲟鱼软骨  II型胶原蛋白  提取  结构鉴定

英文关键词:sturgeon cartilage  collagen type II  extraction  structural identification

中文摘要:

      目的 提取鲟鱼软骨中II型胶原蛋白, 并鉴定其结构。方法 选取鲟鱼软骨为提取对象, 采用碱洗、酸泡法去除非胶原成分、矿物质、多糖等物质, 再用胃蛋白酶酶解法、氯化钠盐析法、去离子水透析法、冷冻干燥法等提取纯化II型胶原蛋白; 采用十二烷基硫酸钠聚丙烯酰胺凝胶电泳法(sodium dodecyl sulfate polyacrylamide gel electrophoresis, SDS-PAGE)、氨基酸分析法、紫外吸收光谱法、傅里叶变换红外光谱法(Fourier transform infrared spectroscopy, FTIR)和圆二色色谱法对提取的II型胶原蛋白进行鉴定。结果 SDS-PAGE电泳结果显示所得提取物至少由2条链组成(α和β); 氨基酸组成分析结果显示, 甘氨酸、丙氨酸和脯氨酸大量存在, 而酪氨酸、半胱氨酸和组氨酸的含量较低; 紫外吸收光谱显示鲟鱼软骨提取物最大吸收峰与蓝鲨软骨和鱿鱼软骨II型胶原蛋白最大吸收峰相近, 此吸收峰是胶原三螺旋结构的典型紫外吸收图谱特点; 红外光谱法和圆二色谱法测定结果表明, 所得提取物具有良好的三螺旋结构, 具备典型II型胶原蛋白吸收特征。结论 从鲟鱼软骨中提取的胶原蛋白为II型胶原蛋白, 且纯度较高。

英文摘要:

      Objective To extract collagen type II from sturgeon cartilage and identify its structure. Methods The sturgeon cartilage was selected as raw materials, and the non collagen components, mineral and polysaccharides were removed by alkali washing and acid pickling. Collagen type II was extracted and purified by pepsin extraction, salting of sodium chloride, dialyzing of ultrapure water and cool-dry. The identification was done by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE), the constitution of amino acid, ultraviolet absorption spectrometry, Fourier transform infrared spectroscopy (FTIR) and circular dichroism. Results SDS-PAGE tests showed that the product was mainly composed of 2 chains (α and β); The content of Gly, Ala, and Pro was highest by amino acid analysis, but the content of Tyr, Cys and His was lower. The ultraviolet absorption spectrum showed that the maximum absorption peak of sturgeon cartilage was similar to the blue shark cartilage and squid cartilage, which was a typical characteristic of collagen type II triple helix structure. FTIR and circular dichroism showed that the extractive had a good triple helical structure and the absorption peak was a typical absorption characteristic of collagen type II. Conclusion The extracted from sturgeon cartilage is collagen type II with high purity.