发酵鱼粉中寡肽检测技术研究

Determination of oligopeptide content in fermented fishmeal

用单宁酸作为发酵鱼粉中水溶性蛋白质的沉淀剂,经飞行时间质谱仪测得滤液中蛋白质分子量在2 047.98 Da以下。用双缩脲反应法可以测出发酵鱼粉中水溶性总肽的含量,用凯氏定氮法可以测出被沉淀的多肽的含量,从而可以计算出发酵鱼粉中寡肽的含量。用该技术测得2 546 Da和1 500 Da的低分子量蛋白的回收率分别为92.42%和5.91%。

Tannic acid was used to precipitate soluble proteins in fermented fishmeal. Applying a time-of-flight mass spectrometer, the molecular weight of the protein in the filtrate was found to be lower than 2047.98Da. Total solvable peptide content in the fermented fishmeal was determined by using the biuret method, and polypeptide in the precipitate by using Kjeldahl method. Then, the oligopeptide content was calculated. This determination method showed recovery rates for the 2546 Da and 1500 Da low molecular weight proteins to be 92.42% and 5.91%, respectively.