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

BACKGROUND: 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. RESULTS: 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. CONCLUSIONS: 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.