Bacterial cellulose doped with ZnO as a multifunctional bioactive platform for curcumin and propolis immobilization:...

Bacterial cellulose (BC)-based dressings exhibit favorable hydrogel characteristics, including high biocompatibility, moisture regulation, and mechanical adaptability, making them suitable candidates for biomedical applications. In this study, an integrated approach was employed to develop multifunctional, bioactive bionanocomposites. A cellulose-producing bacterial strain, Limosilactobacillus fermentum 6BC (accession number OM978241.1), was isolated from spoiled grapes and identified through 16 S rRNA gene sequencing. The structural and chemical characteristics of the synthesized BC were analyzed using Transmission electron microscopy (TEM), scanning electron microscopy (SEM), Fourier-transform infrared spectroscopy (FTIR), and X-ray diffraction (XRD). To enhance the biological functionality of BC, zinc oxide (ZnO) nanoparticles were incorporated via a sono-coprecipitation method to produce ZnO-decorated BC (BCZO). The resulting BCZO was subsequently integrated into a hydroxypropyl ethyl cellulose (HPEC) matrix, forming a bionanoplatform designed for the immobilization of bioactive agents, specifically curcumin (Cc) and propolis extract (Pp). TEM was used to examine the nanoscale distribution of ZnO, while FTIR, XRD, SEM, and EDS were employed to characterize the composite structure and confirm drug incorporation. The fabricated scaffolds were further subjected to comprehensive antimicrobial, antioxidant, cytocompatibility, and in vitro wound healing assessments to evaluate their biological performance. The antimicrobial assays demonstrated effective inhibition of L. monocytogenes, S. aureus, E. coli, Salmonella sp., and the fungus C. albicans. The bionanoplatforms also exhibited concentration-dependent antioxidant activity in DPPH and ABTS assays (ascorbic acid as control). The cytocompatibility tests on human skin fibroblasts (HFB-4) showed excellent cell viability across all formulations. Among them, Cc/Pp50@BCZO/HPEC displayed the exciting antimicrobial and antioxidant performance, coupled with desirable cytocompatibility. Thus this study offers a systematic framework for engineering cellulose-based bioplatforms as bioactive materials for potential drug delivery and wound-healing applications.