小麦低聚肽中抗氧化肽的分离纯化及结构鉴定

Separation and Identification of Antioxidant Peptides Derived from Wheat Oligopeptides

为了考察小麦低聚肽中抗氧化肽的活性和结构,试验以谷朊粉为原料,采用两步酶解法制备出小麦低聚肽,在对其基础理化成分进行分析的基础上,测定了其总抗氧化活性。结果表明,小麦低聚肽中总蛋白质含量为98.32%±7.25%,酸溶蛋白质含量为93.71%±7.10%,脂肪含量为0.05%±0.01%、灰分含量为4.35%±0.46%、水分含量为4.28%±0.33%。小麦低聚肽的总抗氧化能力为2.3±0.1 mmol/100 g。然后利用反相高效液相色谱(RP-HPLC)对小麦低聚肽进行分离纯化,收集6个主要的组分峰,利用Q-TOF质谱仪测定肽序列,鉴定出的15个肽段中,有3个肽段PY、LY和APSY的总抗氧化能力比小麦低聚肽强,分别为3.0±0.2,2.7±0.2和2.4±0.1 mmol/100 g。

In order to investigate the activity and structure of antioxidant peptides derived from wheat oligopeptides（WOP）, WOP was prepared by the method of two-step enzymolysis. On the basis of analysis of component, the antioxidant activity of WOP was determined. The results showed that the contents of total protein, acid soluble protein, fat, ash and moisture were 98.32%±7.25%, 93.71%±7.10%, 93.71%±7.10%, 4.35%±0.46%, and 4.28%±0.33%, respectively. The total antioxidant capacity of WOP was 2.3±0.1 mmol/100 g. Then, WOP was separated and purified by reversed phase high performance liquid chromatography（RP-HPLC） and 6 major fractions were collected. The fractions were performed on the Q-TOF mass spectrometer. Among the 15 identified peptides, three peptides（PY, LY, and APSY） exhibited total antioxidant activities（3.0±0.2, 2.7±0.2, and 2.4±0.1 mmol/100 g, respectively） higher than WOP.