酶解大豆蛋白抗氧化肽的分离纯化与鉴定

Isolation and Identification of Antioxidant Peptides from Enzymatically Hydrolyzed Soybean Protein

对前期优化的碱性蛋白酶最优酶解条件下的大豆蛋白抗氧化肽进行进一步分离、纯化及鉴定。采用高效强阴离子交换柱(HiTrap Q HP)、快速弱阴离子交换柱(HiTrap DEAE-FF)和制备液相色谱方法,对酶解液进行分离纯化,获得高纯度的抗氧化肽SHP-1。通过液相色谱-串联质谱(liquid chromatography-tandem mass spectrometry,LC-MS/MS)测定抗氧化肽SHP-1的分子质量,为741.41 Da;采用氨基酸分析仪对抗氧化肽SHP-1的组成进行分析,表明抗氧化肽SHP-1是由5种氨基酸组成。通过LC-MS/MS对抗氧化肽SHP-1氨基序列进行解析并与大豆蛋白数据库比对,确定抗氧化肽SHP-1氨基酸序列为IPPGVPY,来自于大豆球蛋白G4亚基。

A high-purity antioxidant peptide SHP-1 was purified from enzymatically hydrolyzed soybean protein prepared under previously optimized conditions by high-efficiency strong anion exchange column(HiTrap Q HP), fast weak anion exchange column(HiTrap DEAE-FF) and preparative liquid chromatography. The molecular mass of the peptide was determined to be 741.41 Da by liquid chromatography-tandem mass spectrometry(LC-MS/MS). The amino acid composition of SHP-1 was analyzed by an amino acid analyzer, revealing that it is composed of five amino acids. By using LC-MS/MS as well as comparison to the soybean protein database, the amino acid sequence of SHP-1 was determined to be IPPGVPY, which is derived from the G4 subunit of glycinin.