松仁谷蛋白抗氧化肽的分离纯化及一级结构鉴定

利用碱性蛋白酶酶解制备松仁谷蛋白水解物,采用超滤、Sephadex G-25、Sephadex G-15及反相高效液相色谱对酶解物进行分离纯化,并利用质谱进行结构鉴定。对质谱结果进行从头测序,筛选得到两种抗氧化肽肽段Glu-Leu-Leu-Lys-Leu-His(ELLKLH)、Glu-Lys-Asp-Phe-His-Leu(EKDFHL)。经固相合成后得到纯度分别为99.67%和95.15%的肽段,对其进行抗氧化活性测定。结果表明,在浓度为1 000 μmol/m L时,ELLKLH和EKDFHL的1,1-二苯基-2-三硝基苯肼自由基清除率分别为38.26%和29.54%,铁离子螯合率分别为56.44%和48.66%。

Isolation,Purification and Structural Analysis of Antioxidant Peptides Derived from Gluten in Pinus koraiensis Sieb.et Zucc Nut Kernels

In this work, the enzymatic hydrolysate of pine nut gluten produced with alkaline protease was isolated and purified by ultrafiltration, Sephadex G-25, Sephadex G-15 and reversed-phase high-performance liquid chromatography (RP-HPLC). The structural characteristics of the purified fractions were identified by Q Exactive hybrid quadrupole-Orbitrap mass spectrometry, and de novo sequencing was performed based on the mass spectral data. Two antioxidant peptides were obtained with amino acid sequence of Glu-Leu-Leu-Lys-Leu-His (ELLKLH) and Glu-Lys-Asp-Phe-His-Leu (EKDFHL), respectively. After solid-phase synthesis, the purity of the peptides was 99.67% and 95.15%, respectively. The results of antioxidant activities showed that the DPPH free radical scavenging rates of ELLKLH and EKDFHL at a concentration of 1 000 μmol/mL were 38.26% and 29.54%, respectively, and the iron ion chelating rates were 56.44% and 48.66%, respectively.