This study presents the ex situ development and characterization of bacterial cellulose (BC) membranes loaded with bioactive Sage and Neem extracts for enhanced antimicrobial applications. Utilizing discarded fruit waste as a cost-effective carbon source, BC production was optimized, yielding membranes with improved properties. Neem and Sage extracts, obtained via Soxhlet extraction, exhibited significant antibacterial activity against Escherichia coli and Staphylococcus aureus, with minimum inhibitory concentrations of 3.125 mg/mL and 25 mg/mL, respectively, for Neem extract, and 25 mg/mL and 50 mg/mL for Sage extract. These extracts (20 wt%) were successfully incorporated into BC membranes ex situ, resulting in BC-Neem (BC-N) and BC-Sage (BC-S) composites. Fourier-transform infrared spectroscopy (FTIR) confirmed the chemical interactions between the extracts and the BC matrix, revealing the introduction of new functional groups and enhancing the composite properties. Scanning electron microscopy (SEM) illustrated changes in morphology, indicating deeper penetration and attachment of the extracts within the BC structure. Quantitative analysis of water holding capacity demonstrated that BC-N and BC-S absorbed about 90 times water of their dry weight. Antibacterial assays through the colony-forming unit method showed that BC-N significantly inhibited S. aureus growth by 78 % and E. coli by 51 %, while BC-S exhibited a 48 % reduction against S. aureus. Agar disc-diffusion assay showed the formation of inhibition zones of 1.2 cm and 0.1 cm by BC-N against S. aureus and E. coli, respectively, in contrast to 0.2 cm and no inhibition by BC-S composite. These results highlight the potential of bioactive plant extract-loaded BC membranes as effective antimicrobial agents, offering a sustainable alternative to conventional materials in medical and food packaging applications.
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