远东拟沙丁鱼抗氧化肽的分离纯化及结构解析

通过动物蛋白酶和风味酶联合水解,采用超滤等膜分离技术制备远东拟沙丁鱼蛋白多肽,得到不同分子质量区间的多肽样品F1(100~3000 u)、F2(3000~10000 u)和F3(大于10000 u)。以DPPH、ABTS和羟基自由基清除能力为检测指标,测定各组分的抗氧化活性,结果显示:组分F1的抗氧化活性最强。进一步对远东拟沙丁鱼蛋白多肽F1进行分离。以ABTS自由基清除能力为筛选指标,采用强阴离子、反向色谱柱YMC-pack-OSD-AQ进行逐级分离收集,筛选出2个具有抗氧化活性较强的肽段(b-f1和b-f6)。采用ESI MS/MS测定其氨基酸结构,结果显示:b-f1的分子质量均为436 u,其氨基酸序列是Arg-Phe-Asp(RFD)或Trp-Thr-Met(WTM);b-f6的分子质量为700 u,其氨基酸序列为Phe-Ala-His-Asp-Asp-Pro。b-f1和b-f6对ABST自由基清除能力分别为(81.22±4.12)%和(76.35±3.32)%。

Isolation,Purification and Structural Analysis of Antioxidant Peptides from Sardinops sagax

The polypeptide was prepared from the Sardinops sagax by the combination hydrolysis by animal proteolytic enzymes and flavor enzyme,then separated by ultrafiltration membrane.The peptides of different molecular weight range were F1(100-3000 u),F2(3000-10000 u)and F3(≥10000 u).The antioxidant activity of each component was determined by DPPH,ABTS and hydroxyl free radical scavenging ability.The results showed that the antioxidant activity of component F1 was the strongest.Using ABTS free radical scavenging capacity as screening indexes,two antioxidant peptides coded b-f1 and b-f6 were separated and purified by the strong anion and YMC-pack-OSD-AQ.The sequences of these peptide were identified by ESI MS/MS as follow.The sequence of antioxidant peptide b-f1 was Arg-Phe-Asp(RFD)/Trp-Thr-Met(WTM)with molecular mass of 436 u,and the sequence of antioxidant peptide b-f6 was Phe-Ala-His-Asp-Asp-Pro with molecular mass of 700 u.The ABTS free radical scavenging capacity of b-f1 and b-f6 were(81.22±4.12)%,(76.35±3.32)%,respectively.