基于串联质谱的鱼皮明胶鉴别研究

在胶原蛋白序列比对基础上，以虹鳟鱼明胶、猪明胶和牛明胶为模型，利用高效液相色谱－串联质谱技术（HPLC-MS/MS）研究了3种明胶降解多肽组成的差异。使用胰蛋白酶将鱼皮明胶进行了酶解处理，使用HPLC-MS/MS对酶解产物中的多肽组成进行了分析，并与猪和牛明胶酶解产物中的多肽进行了比较。结果表明鱼明胶酶解产物中存在特征多肽，通过特征多肽的种类可区别鱼明胶与猪和牛明胶，研究了明胶多肽中脯氨酸羟基化修饰、明胶分子量范围和脱酰胺化对特征多肽识别的影响。研究表明利用HPLC-MS/MS技术通过识别明胶酶解产物中的特征多肽进行鱼皮明胶鉴别具有可行性。

Differentiation of Fish Gelatin from Bovine/porcine Gelatin by Tandem Mass Spectrometry

Sequence alignment analysis indicated that bovine, porcine and fish collagen type I contain differential sequences, which might be used as marker peptides for gelatin differentiation. In this research, bovine, porcine and fish gelatin were digested by trypsin. The peptides in the digest mixtures were identified by high performance liquid chromatography/mass spectrometry (HPLC/MS). Marker peptides specific for fish collagen type I were found in the digested fish gelatin. Actual sample analysis indicated that fish gelatin might be identified according to the marker peptides detected. The effect of hydroxylation of proline and the molecular weight range of gelatin on the relative abundance of marker peptides were also investigated. This research demonstrated that fish gelatin can be differentiated by detection of marker peptides in the tryptic digest of sample gelatin.