中文摘要：

胶原与其变性产物明胶虽然具有同源性,但两者在结构和性能上却有明显的差异。本文采用紫外光谱法（UV）、傅立叶变换红外光谱法（FT-IR）、圆二色谱法（CD）、超灵敏差示扫描量热法（US-DSC）、Zeta电位仪和原子力显微镜（AFM）,研究了从牛跟腱中提取的I型胶原及其加热变性产物明胶的结构,并对各种方法所得结果进行了对比分析。结果表明,UV光谱不适于胶原和明胶的结构鉴定;FT-IR可以反映出胶原特征的三股螺旋结构,明胶因不存在完整的三股螺旋结构而不具有同样典型的图谱特征;CD是区分胶原和明胶构象的直接手段;US-DSC能灵敏地监测胶原的热变性转变过程,而明胶因不存在三股螺旋到无规卷曲的相变过程故没有吸热峰出现;Zeta电位方法还有待于进一步研究;AFM图像可以直接地观测胶原的纤维结构,其与明胶的形貌结构有明显不同。

英文摘要：

Collagen and its denatured product,gelatin,can have the same origin,however,their structures and properties are significantly different.In the present study,the methods of ultraviolet spectroscopy（UV）,Fourier transform infrared spectroscopy（FT-IR）,circular dichroism（CD）,ultra-sensitive differential scanning calorimetry（US-DSC）,Zeta potential,and atomic force microscopy（AFM） have been used to study structures of the collagen extracted from bovine tendon and the gelatin derived from the collagen.The results indicate that collagen and gelatin can not be distinguished by UV measurements.However,they show different FT-IR characterizations.CD directly indicates the triple helix conformation of collagen,while gelatin no such structural spectrum.The transition from triple helix to random coil of collagen can be sensitively monitored by US-DSC,meanwhile,gelatin has no such transition.Zeta potential method need to be further studied.And AFM observation reveals the fibrillar structure of collagen on mica;nevertheless gelatin presents different morphology.The present work is significant for structure investigation of protein.