Propolis-functionalized acellular fish skin scaffolds as biotechnological platforms for antimicrobial activity and regenerative wound healing

Biotechnological advances in tissue engineering increasingly exploit naturally derived scaffolds as bioactive delivery systems. Acellular fish skin (AFS) provides a collagen-rich extracellular matrix favorable for tissue regeneration but lacks intrinsic antimicrobial activity. Propolis, a polyphenol-rich natural resin, exhibits antimicrobial, antioxidant, and immunomodulatory properties, yet its direct application is limited by burst release and local cytotoxicity. In this study, we aimed to develop and characterize a propolis-functionalized AFS scaffold as a multifunctional biomaterial capable of combining sustained antimicrobial activity with regenerative support for wound-healing applications. Lipid-preserved Tilapia-derived AFS was biofunctionalized with ethanolic propolis extract (EPE) through a vacuum-assisted impregnation process to obtain an EPE-AFS hybrid scaffold. The biotechnological modification preserved the collagenous architecture and porosity of the matrix, enhanced surface hydrophilicity (contact angle reduced from 91° ± 2° to 67° ± 3°), and maintained mechanical integrity (~ 13 MPa). Spectroscopic and microscopic analyses (FTIR, FE-SEM) confirmed successful deposition of polyphenolic components. The release profile demonstrated sustained polyphenol diffusion over 96 h (> 90% cumulative release). Functionally, cellular assays confirmed enhanced fibroblast adhesion and migration on propolis-functionalized scaffolds. Gene expression analysis revealed transcriptional upregulation of extracellular matrix remodeling and angiogenesis-associated markers (COL1A1, COL3A1, VEGF, TGF-β1), alongside downregulation of inflammation-related transcripts (IL-6, MMP-9). Antibacterial evaluation based on turbidity measurements indicated effective growth inhibition against Staphylococcus aureus and Escherichia coli. This study demonstrates a biotechnological strategy for functionalizing natural collagen scaffolds with propolis-derived polyphenols, yielding a dual-action biomaterial that combines sustained antibacterial growth suppression with enhanced regenerative-associated signaling in vitro. The EPE–AFS construct represents a promising nature-derived platform for further preclinical investigation in wound-healing applications. While these findings reveal a pro-regenerative and anti-inflammatory transcriptional profile in fibroblasts, additional validation—including endothelial and immune cell functional assays and in vivo wound models—is required to confirm angiogenic, immunomodulatory, and therapeutic efficacy under physiologically relevant conditions.