核桃肽铁螯合物的制备及其结构表征  

Preparation and structural characterization of walnut peptide-ferrous chelate

作　　者：林栋[1] 张咏清 肖自芬 李雪 张丽赟 李莹[1] 骆衡 LIN Dong;ZHANG Yongqing;XIAO Zifen;LI Xue;ZHANG Liyun;LI Ying;LUO Heng(College of Food Science and Engineering,Guiyang University,Guiyang 550005,China;State Key Laboratory of Functions and Applications of Medicinal Plants,Guizhou Medical University,Guiyang 550014,China)

机构地区：[1]贵阳学院食品科学与工程学院,贵州贵阳550005 [2]贵州医科大学药用植物功效与利用国家重点实验室,贵州贵阳550014

出　　处：《食品与发酵工业》2025年第4期221-227,235,共8页Food and Fermentation Industries

基　　金：贵州省科技计划项目(黔科合基础-ZK[2021]一般177);贵州省教育厅高等学校科学研究项目(青年项目)(黔教技(2022)301号);贵阳学院2021年硕士研究生科研项目基金(GYU-YJS[2021]-37)。

摘　　要：为充分利用核桃粕资源,同时解决传统补铁剂生物可及性低的问题,该研究采用正交试验优化制备了核桃肽-铁螯合物;通过紫外光谱、荧光光谱、扫描电镜、氨基酸分析及红外光谱对核桃肽-铁螯合物的结构进行表征;通过体外胃肠模拟消化实验探究核桃肽-铁螯合物Fe^(2+)释放率;运用噻唑蓝法探究螯合物对Caco-2细胞活力的影响。结果表明,核桃肽-铁螯合物的最佳制备条件为多肽质量浓度4%,pH 7,核桃肽/FeCl_(2)质量比3∶1,反应温度40℃,反应时间40 min。在此条件下,螯合物中Fe^(2+)螯合率可达91.99%。Fe^(2+)引入后,核桃肽的表观形貌由光滑平面转变为疏松多孔的颗粒。红外光谱结果表明,Fe^(2+)主要通过羧基氧和氨基氮原子与核桃肽螯合。体外模拟胃肠道消化和细胞毒性实验结果表明,相比于硫酸亚铁,核桃肽-铁螯合物具有更高的Fe^(2+)释放率和安全性。该研究结果将为核桃加工副产物的高值化利用及新型膳食铁补充剂的开发提供有益参考。To make full use of the resources of the walnut meal and also solve the problem of low bioaccessibility of traditional iron supplements,the present study optimized the preparation of walnut peptide-ferrous chelates(WP-Fe)using orthogonal tests,characterized the structure of WP-Fe by UV spectroscopy,fluorescence spectroscopy,scanning electron microscopy,amino acid analysis,and infrared spectroscopy,investigated the release rate of Fe^(2+)from WP-Fe by in vitro gastrointestinal simulated digestion test,and investigated the effects of WP-Fe on the viability of Caco-2 cells by MTT assay.Results indicated that the optimal conditions for the preparation of WP-Fe were peptide concentration of 4%,pH 7,mass ratio of walnut peptide/FeCl_(2) of 3∶1,reaction temperature of 40℃,and reaction time of 40 min,under which the chelation rate of Fe^(2+)in WP-Fe could reach 91.99%.The apparent morphology of walnut peptides was transformed from smooth planar surfaces to loose and porous particles after the addition of Fe^(2+).The results of infrared spectroscopy showed that Fe^(2+)was chelated with walnut peptide mainly through carboxy oxygen and amino nitrogen atoms.The results of in vitro simulated gastrointestinal digestion and cytotoxicity tests showed that WP-Fe had a higher Fe^(2+)release rate and safety compared with ferrous sulfate.The findings will provide a beneficial reference for the high-value utilization of walnut processing by-products and the development of novel dietary iron supplements.

关 键 词：核桃 补铁剂 螯合物 结构表征 生物可及性 

分 类 号：TS209[轻工技术与工程—食品科学] TS202.3[轻工技术与工程—食品科学与工程]