驴乳粉蛋白的特性、结构与组成分析

Analysis of Characteristics,Structure and Composition of Protein in Donkey Milk Powder

采用十二烷基硫酸钠-聚丙烯酰胺凝胶电泳、圆二色谱和基质辅助激光解析电离-飞行时间质谱法研究德州驴乳粉蛋白质的性质、结构和组成,为德州驴乳的深层次开发提供依据。结果表明,驴乳粉蛋白质量分数为16.10%,等电点均匀分布在4.5~6.5之间,分子质量主要集中在10~20 kDa和53~78 kDa的乳清蛋白区域,以及28~36 kDa酪蛋白区域。通过与马科蛋白图库进行对比,检索出386种可识别的蛋白,其中有139种蛋白首次在驴乳中发现,为揭示驴乳的生理功效提供理论基础。

Sodium dodecyl sulfate-polyacrylamide gel electrophoresis(SDS-PAGE),circular dichroism spectroscopy and matrix assisted laser desorption ionization time-of-flight mass spectrometry(MALDI-TOF/TOF-MS)were used to reveal the properties,structure and composition of milk powder protein from Dezhou donkeys,aiming to provide a basis for the deep exploitation of Dezhou donkey milk.The results showed that the protein content of the milk powder was 16.10%,the isoelectric point was evenly distributed between 4.5 and 6.5,and the molecular mass was mainly concentrated in the range of 10–20 and 53–78 kDa for whey protein,and 28–36 kDa for casein.By matching against the equine protein library,386 proteins were identified,139 of which were first discovered in donkey milk.This study provides a theoretical basis for revealing the physiological effects of donkey milk.