Upcycling soybean okara proteins into 3D printable bioactive peptide-enhanced PCL composite for wound-care applications

Food by-product valorization offers a promising route to generate high-value functional ingredients while supporting sustainable circular bio-economy models. This study investigates a protein hydrolysate from soy okara waste (OH) as a source of bioactive peptides for skin health and tissue repair. Using human dermal fibroblasts, OH demonstrated antioxidant activity by reducing reactive oxygen species, NRF2 and catalase enzymes. OH also exerted anti-inflammatory effects by modulating the NF-κB pathway, reducing TNF-α secretion, and enhancing fibroblast migration in a wound-healing model. To explore material-based delivery strategies, OH was incorporated into poly(ε-caprolactone) (PCL), thereby generating a 3D-printable bioactive blend (PCL-OH). Mechanical, thermal, and structural analyses confirmed the preservation of PCL properties and a sustained peptide release profile. Biological assays showed that the PCL-OH blend retained antioxidant, anti-inflammatory, and pro-healing activities, confirming its potential as a novel bioactive material. Complex designs were 3D-printed using the novel material to demonstrate its potential from both design and manufacturability perspectives. Overall, this work demonstrates how food-processing by-products can serve as functional bioactive ingredients for biodegradable materials in sustainable biomedical and wound-care applications. Food by-product valorization produces high-value ingredients and supports a circular bioeconomy. Here, the authors convert soy okara waste into a 3D-printable bioactive material for wound healing and biomedical applications.