Antioxidant Peptides Derived from Woody Oil Resources: Mechanisms of Redox Protection and Emerging Therapeutic Opportunities

Abstract

Antioxidant peptides derived from woody oil resource by-products exhibit strong free radical scavenging abilities and offer potential applications in functional foods, nutraceuticals, and cosmetics. This review summarizes the latest advances in preparation technologies, including enzymatic hydrolysis, microbial fermentation, chemical synthesis, recombinant expression, and molecular imprinting, each with distinct advantages in yield, selectivity, and scalability. The structure-activity relationships of antioxidant peptides are explored with respect to amino acid composition, molecular weight, and 3D conformation, which collectively determine their bioactivity and stability. Additionally, emerging delivery systems-such as nanoliposomes, microencapsulation, and cell-penetrating peptides-are discussed for their role in enhancing peptide stability, absorption, and targeted release. Mechanistic studies reveal that antioxidant peptides from woody oil resources act through network pharmacology, engaging core signaling pathways, including Nrf2/ARE, PI3K/Akt, AMPK, and JAK/STAT, to regulate oxidative stress, mitochondrial health, and inflammation. Preliminary safety data from in vitro, animal, and early clinical studies suggest low toxicity and favorable tolerability. The integration of omics technologies, molecular docking, and bioinformatics is accelerating the mechanism-driven design and functional validation of peptides. In conclusion, antioxidant peptides derived from woody oil resources represent a sustainable, multifunctional, and scalable solution for improving human health and promoting a circular bioeconomy. Future research should focus on structural optimization, delivery enhancement, and clinical validation to facilitate their industrial translation.

Keywords: AMPK; JAK/STAT; Keap1/Nrf2/ARE; PI3K/Akt; antioxidant peptides; bioavailability; functional foods; molecular docking; signal transduction pathways; woody oil resources.

Figure 1

Schematic route from woody oil resources to antioxidant peptides. Pre-treated woody oil seeds or by-products are subjected to either large-scale enzymatic hydrolysis/fermentation or precision synthesis approaches such as chemical or recombinant methods. A subsequent molecular imprinting enrichment step selectively isolates target peptides, which are ultimately applied in food, nutraceutical, and pharmaceutical products.

Figure 2

The antioxidant potency of bioactive peptides is dictated by three interlinked factors: amino acid composition, molecular weight range, and three-dimensional conformation.

Figure 3

Chemical structures of antioxidant-relevant amino acids (cysteine, histidine, lysine, tryptophan, tyrosine, and glutamic acid), whose thiol, imidazole, ε-amino, indole, phenolic, and γ-carboxylate side chains contribute to radical scavenging and metal-chelating activity in bioactive peptides.

Figure 4

Schematic of oral delivery showing gastrointestinal barriers and five carrier strategies: enteric coating, nanoliposomes, nanocarriers, microencapsulation, and cell-penetrating peptides, which safeguard antioxidant peptides en route to systemic circulation and diverse target cells.

Figure 5

Antioxidant peptides derived from woody oil resources act via network pharmacology, synchronously engaging Keap1–Nrf2, PI3K–Akt, AMPK, and JAK/STAT pathways to coordinate antioxidant gene expression, metabolic–redox homeostasis, and cell survival control. This highlights their multi-target potential for precision nutrition and disease intervention.