牡蛎DPP-Ⅳ抑制肽的结构特征及其协同花色苷的活性增效作用研究

Structural characterization and synergistic inhibition of DPP-Ⅳactivity of oyster peptides and anthocyanins

为探讨牡蛎肽对二肽基肽酶Ⅳ(dipeptidyl peptidaseⅣ,DPP-Ⅳ)的抑制活性及其协同花色苷的增效作用,通过酶解法制备牡蛎肽,对其结构进行表征,采用体外DPP-Ⅳ活性抑制模型与Compusyn协同计算模型分析牡蛎DPP-Ⅳ抑制肽协同花色苷抑制DPP-Ⅳ活性的增效作用。结果表明:牡蛎肽的分子质量主要集中在3 kDa以下(55.44%),其氨基酸组成中支链氨基酸(branched chain amino acids,BCAAs)和脯氨酸(Pro)占疏水性氨基酸总量的60.84%;肽谱分析显示牡蛎肽中主要的17条肽段N端富含BCAAs和Pro,具有显著的DPP-Ⅳ抑制肽结构特征。筛选合成的5条肽(FPVGR、APPNIT、IAPPERK、LDFYLDIP、LAIL)中FPVGR的DPP-Ⅳ抑制活性最强(P<0.05);6种常见的花色苷:芍药色素/矢车菊素/锦葵色素/飞燕草素/天竺葵色素/矮牵牛色素-3-O-葡萄糖苷(Pn3G,C3G,Mv3G,D3G,Pg3G,Pt3G)中Pn3G、C3G和Mv3G的DPP-Ⅳ抑制活性最强(P<0.05);协同作用研究显示FPVGR与Pn3G/C3G/Mv3G均具有协同抑制DPP-Ⅳ的作用(当抑制率为50%时,CI值分别为0.89、0.93、0.89)。该研究为进一步开展DPP-Ⅳ抑制肽和花色苷的活性增效研究提供了科学依据。

In order to investigate the inhibitory activity of oyster peptides against dipeptidyl peptidaseⅣ(DPP-Ⅳ),as well as their synergistic effects with anthocyanins,oyster peptides were obtained using the enzymatic hydrolysis method,and their structures were characterized.Furthermore,an in vitro DPP-Ⅳactivity inhibition model and the Compusyn collaborative calculation model were used to analyze the synergistic effect of oyster DPP-Ⅳinhibitory peptides and anthocyanins in inhibiting DPP-Ⅳactivity.The results indicated that the molecular weight of oyster peptides was primarily below 3 kDa(55.44%),with branched-chain amino acids(BCAAs)and proline(Pro)accounting for 60.84%of the total hydrophobic amino acids.Peptide profiling analysis revealed that the predominant 17 peptide segments in oyster peptides were significantly enriched in BCAAs and Pro at the N-terminus,displaying significant structural characteristics of DPP-Ⅳinhibitory peptides.Among the five peptides synthesized through screening(FPVGR,APPNIT,IAPPERK,LDFYLDIP,LAIL),FPVGR exhibited the strongest DPP-Ⅳinhibitory activity(P<0.05).Moreover,among the six common anthocyanins(peonidin/cyanidin/malvidin/delphinidin/pelargonidin/petunidin-3-O-glucoside:Pn3G,C3G,Mv3G,D3G,Pg3G,Pt3G),Pn3G,C3G,and Mv3G demonstrated the strongest DPP-Ⅳinhibitory activity(P<0.05).Synergy studies revealed that FPVGR and Pn3G/C3G/Mv3G displayed synergistic inhibitory effects against DPP-Ⅳ(with CI values of 0.89,0.93,and 0.89,respectively,at a 50%inhibition rate).This study provides a scientific foundation for further research on the synergistic activity of DPP-Ⅳinhibitory peptides and anthocyanins.