具有铅离子螯合作用的亚麻籽蛋白源半胱氨酸肽的制备及结构鉴定  

Preparation and Structure Identification of Flaxseed Protein-Derived Cysteine Peptides for Lead Ion Chelation

作　　者：关心语 包小兰[1] Guan Xinyu;Bao Xiaolan(College of Food Science and Engineering,Inner Mongolia Agricultural University,Huhehaote 010018)

机构地区：[1]内蒙古农业大学食品科学与工程学院,呼和浩特010018

出　　处：《中国粮油学报》2025年第1期76-83,共8页Journal of the Chinese Cereals and Oils Association

基　　金：国家自然科学基金项目(32360553);内蒙古自治区自然科学基金项目(2023MS03017);内蒙古自治区直属高校基本科研业务费项目(BR231401);2022年食品科学与工程学院科技计划项目(SPKJ202212)。

摘　　要：研究发现含有半胱氨酸残基即巯基的植物蛋白肽具有铅离子螯合能力,可以降低铅中毒人群体内铅的浓度,缓解中毒症状,减轻铅损伤。本研究以脱脂亚麻籽饼为原料,从中提取亚麻籽蛋白并进行酶解,优化酶解工艺得到高巯基含量的酶解物,采用共价色谱法对亚麻籽蛋白酶解物中半胱氨酸肽进行富集,并鉴定其结构,最后通过分子对接技术探究其与铅离子的螯合机制,旨在获得具有铅离子螯合作用的半胱氨酸肽。结果发现,采用protease M酶,在酶解温度50℃、酶解pH 3.5、酶添加量900 U/g、酶解时间4 h条件下,得到巯基含量为13.37μmol/g的亚麻籽蛋白酶解肽,铅离子螯合量为11.40 mg/g;通过共价色谱法对其进行富集得到巯基含量为44.8μmol/g、铅离子螯合量为24.98 mg/g的亚麻籽蛋白源半胱氨酸肽,比亚麻籽蛋白提高了6.74倍和3.92倍;对亚麻籽蛋白源半胱氨酸肽进行结构鉴定,得到3种含有半胱氨酸的肽段,分别为WAIINLQHSGEGLCGRVV、CTGLLEAVAAALMMNIYIVGLNQLTDIE、QGGQGQQQQCEKQIQEQDYLRSCQQFLWEKV-QKGGRS,且3种肽段都可以与铅离子稳定螯合,其中半胱氨酸中的巯基在螯合过程中起重要作用。以上结果表明,对亚麻籽蛋白酶解工艺进行优化并富集,可以得到高巯基含量且能与铅离子螯合的半胱氨酸肽,提高亚麻籽榨油后副产物的利用率,并为亚麻籽蛋白源半胱氨酸肽缓解铅中毒的研究提供理论依据。In research,it has been found that plant protein peptides containing cysteine residues,namely sulfhydryl groups,had lead ion chelation ability,reducing the concentration of lead in the body of lead-poisoned patients,alleviate poisoning symptoms,and mitigate lead damage.In this study,the defatted flaxseed cake was used as a raw material,from which the flaxseed protein was extracted and enzymatically digested,optimization of enzymatic hydrolysis with high sulfhydryl content of digestion,and the enzymatic process was optimized to obtain the enzymatic digest with high sulfhydryl content,the cysteine peptide in the enzymatic digest of flaxseed protein was enriched by covalent chromatography,and identification of its structure,finally,the chelating mechanism of the flaxseed protein and the lead ions was probed by molecular docking technology,aiming at obtaining the cysteine peptide with the effect of chelating the lead ions.The results indicated that the enzyme protease M was used to obtain 13.37μmol/g of sulfhydryl peptide and 11.40 mg/g of lead ion chelating under the conditions of 50℃,pH 3.5,900 U/g of enzyme addition,and 4h.The sulfhydryl peptide with a sulfhydryl content of 44.8μmol/g and a chelating amount of 24.4mg/g of lead ion were obtained by covalent chromatography,and the structure was characterized by molecular docking.By covalent chromatography,it was enriched to obtain a cysteine peptide of flaxseed protein source with a sulfhydryl content of 44.8μmol/g and a lead ion chelating amount of 24.98mg/g,6.74-fold and 3.92-fold higher than that of flaxseed protein;and the structural characterization of the cysteine peptide of flaxseed protein source yielded three peptide fragments containing cysteine,being WAIINLQHSGEGLCGRVV,CTGLLEAVAAALMMNIYIVGLNQLTDIE and QGGQGQQQQQCEKQIQEQDYLRSCQQFLWEKVQKGGRS,respectively,and the three peptides can be stably chelated with lead ions,in which the sulfhydryl group in the cysteine plays an important role in the chelation process.The above results indicated that the optimiza

关 键 词：亚麻籽蛋白 半胱氨酸肽 正交实验 制备 结构鉴定 

分 类 号：TS[轻工技术与工程]