Plant protein-derived antioxidant peptides: Isolation, identification, mechanism of action and application in food systems: A review

Background: In recent years, the antioxidant capacity of plant protein-derived peptides has been depicted in a growing number of studies. Plant proteins have been considered as the new source of antioxidant peptides, which not only save energy but also strengthen treatment of oxidation-related diseases and delay the oxidation of food, thus improve the quality of life. Although reports of the preparation, structure, and activity of antioxidant peptides has increased tremendously and some antioxidant peptides have been commercialized. However, research on antioxidant peptides derived from plant proteins still lacks a systematic review and evaluation. Scope and approach: This review summarizes recent advances in plant protein-derived antioxidant peptides, mainly including: (i) Preparation, purification, identification and application of plant protein-derived antioxidant peptides by enzymatic hydrolysis; (ii) Influencing factors, evaluation methods and mechanism of antioxidant protein hydrolysates or peptides; (iii) Future research prospects and existing problems. Key findings and conclusions: The conventional purification and identification of antioxidant peptides are expensive and time-consuming. In order to overcome this problem, computer-aided mathematical models (molecular docking, QSAR research, etc.), bioinformatics tools and real-time updated protein databases have been widely explored and studied. In addition, future research should focus on large-scale commercial production of plant protein-derived antioxidant peptides, comprehensive study of structure-activity relationship of antioxidant peptides, deep understanding of antioxidant mechanism, and verification of health benefits in vivo. This review provides a timely reference for the development of new antioxidant peptides in functional foods and nutritional supplements.