摘要
本研究通过大鼠肠囊外翻法探讨了<3 kDa核桃蛋白肽模拟胃肠消化产物的吸收特性,以抗氧化能力(DPPH自由基清除率、ABTS+自由基清除率、Fe2+螯合率)和活性肽吸收率为指标筛选核桃肽在肠道吸收的最优条件,并应用模拟分子对接技术和Nano-HPLC-MS/MS技术对吸收肽组分进行筛选和鉴定,得到能够以完整形式被吸收并发挥抗氧化活性的新型核桃源肽。结果表明:当核桃肽消化产物吸收浓度为6 mg/mL,吸收时间为2 h时,其抗氧化活性最高且在小肠吸收率最高:进一步通过Nano-HPLC-MS/MS鉴定结果表明0.5~1 kDa活性肽数量最多,其中位于C端/N端氨基酸主要集中在Pro、Thr、Leu,鉴定出33条活性肽能够以完整形式被吸收,穿过肠道屏障;最后通过分子对接技术与DPP-Ⅳ相结合,获得三条结合能最低的活性肽NLRFPL、NPDDEFRPQ、KGHLFPN,其结合能分别为-8.8、-8.6、-8.6 kal/mol,其中KGHLFPN抗氧化能力最强。综上,<3 kDa核桃肽模拟胃肠道消化能够释放抗氧化活性更高且能够被小肠吸收的活性肽为KGHLFPN,本文为探索外源肽小肠吸收特性及筛选鉴定抗氧化肽提供新思路。
This study investigated the absorption characteristics of<3 kDa walnut protein peptides simulating gastrointestinal digestion products using the everted rat sacs method.The optimal conditions for walnut peptide absorption in the intestine were selected based on antioxidant capacity(DPPH free radical clearance rate,ABTS+free radical clearance rate,Fe2+chelation rate)and active peptide absorption rate.The absorbed peptide components were screened and identified using simulated molecular docking technology and Nano-HPLC-MS/MS technology to obtain new walnut derived peptides that could be fully absorbed and had antioxidant activity.The results showed that when the absorption concentration of walnut peptide digestion product was 6 mg/mL,and the absorption time was 2 h,its antioxidant activity was the highest and the absorption rate in the small intestine was the highest.Further identification by Nano-HPLC-MS/MS showed that,the 0.5~1 kDa active peptide was the most numerous,with the C-terminal/N-terminal amino acids mainly concentrated in Pro,Thr,and Leu.Thirty-three active peptides were fully absorbed and crossed the intestinal barrier.By combining molecular docking technology with DPP-IV,the three active peptides NLRFPL,NPDDEFRPQ,and KGHLFPN with the lowest binding energies of−8.8,−8.6,and−8.6 kal/mol,respectively were obtained.Among these,KGHLFPN displayed the strongest antioxidant capacity.In summary,simulating gastrointestinal digestion with<3 kDa walnut peptides could release the active peptide KGHLFPN,which had the highest antioxidant activity and could be absorbed by the small intestine.These findings would provide new ideas for studies exploring the intestinal absorption characteristics of exogenous peptides,and the scre-ening and identification of antioxidant peptides.
作者
李浩铭
李维佳
李佳
方丽
宋佳淇
吴丹
闵伟红
LI Haoming;LI Weijia;LI Jia;FANG Li;SONG Jiaqi;WU Dan;MIN Weihong(College of Food Science and Engineering,Jilin Agricultural University,Changchun 130118,China)
出处
《食品工业科技》
CAS
北大核心
2023年第23期337-345,共9页
Science and Technology of Food Industry
基金
国家自然科学基金青年科学基金项目(32101934)
吉林省教育厅科学技术研究项目(JJKH20220346KJ)。
关键词
核桃肽
肠吸收
抗氧化活性
分子对接
walnut peptide
intestinal absorption
antioxidant activity
molecular docking
