Utilization of Kombucha SCOBY Waste Modified by Fe<sub>3</sub>O<sub>4</sub>/ZIF-8 for Antibacterial Wound Application

Wound dressing is an essential medical device used to cover wounds on the skin, but the lack of wound protection from bacterial infection has become a major issue nowadays. This research aims to develop a wound application from modified symbiotic culture of bacteria and yeast (SCOBY) with Fe3O4/zeolitic imidazolate framework-8 (ZIF-8) that can effectively protect the wound from bacterial infection. Cellulose-based SCOBY waste was obtained through the fermentation process of kombucha tea production at 25 °C for four days. This research studied the effect of varying concentrations of Fe3O4 in Fe3O4/ZIF-8 synthesis (1%, 3%, 5% wt), and different immersion times of SCOBY membrane in Fe3O4/ZIF-8 colloidal solution (60 and 120 minutes). For Fe3O4/ZIF-8 synthesis, magnetite (Fe3O4) with different concentrations was immobilized onto the zeolitic imidazolate framework-8 (ZIF-8) matrix; then, the SCOBY was immersed in the Fe3O4/ZIF-8 colloidal solution to form the SCOBY/Fe3O4/ZIF-8 biocomposite. The biocomposite characteristics were confirmed by scanning electron microscopy (SEM), fourier-transform infrared spectroscopy (FTIR), and X-ray diffraction (XRD). Moreover, the antibacterial activities were observed against Escherichia coli and Staphylococcus aureus bacteria using the disc diffusion method. Based on the results, the SCOBY/ Fe3O4/ZIF-8 biocomposite with Fe3O4 concentration of 3% wt, and immersion time of 120 minutes showed the largest inhibition zone (21 ± 1 mm) against E. coli. It was found that the inhibition zone performed on E. coli bacteria was larger, indicating that E. coli is more resistant than S. aureus. This study demonstrated that the novel SCOBY/Fe3O4/ZIF-8 could be an excellent material for preparing antibacterial wound dressings and therefore warrants further investigation.