Optimization and production of bacterial cellulose from food waste

Bacterial cellulose (BC) is a biodegradable and biocompatible biomaterial with distinctive properties, including high crystallinity, mechanical strength, porosity, and water-retention capacity. However, the relatively high cost of conventional culture media remains a major limitation to its large-scale production. This study aimed to investigate the potential of food and agricultural waste as low-cost substrates for bacterial cellulose production and to compare the resulting BC with that produced using standard Hestrin–Schramm (HS) medium. Sugarcane bagasse and utilized tea were evaluated as alternative carbon and nitrogen sources, respectively, using a SCOBY culture as the inoculum. Fermentation was conducted under static conditions at 30 °C, and bacterial cellulose formation was assessed using different substrate combinations and concentrations. The pH and wet weight of the produced BC were measured, while Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), and field-emission scanning electron microscopy (FE-SEM) were used for characterization. Bacterial cellulose formation was observed with several substrate combinations, with the 1500 mL bagasse-water and utilized-tea medium producing the highest recorded wet weight (55.4854 g), compared with 15.7408 g obtained from the standard HS medium. The pH of the production media after inoculation ranged from 4.0 to 4.5. FTIR spectra of BC produced from bagasse and utilized tea were comparable to those of BC produced using HS medium, indicating similar characteristic functional groups. XRD analysis showed comparable cellulose characteristics between bagasse-derived BC and the standard, while glucose-derived BC showed differences that may be associated with impurities. FE-SEM revealed a densely packed fibrous network with irregularly arranged fibrils in the bagasse-derived BC. Overall, the findings demonstrate the potential of sugarcane bagasse and utilized tea as inexpensive alternative substrates for bacterial cellulose production and food-waste valorization. Further optimization, purification, and scale-up studies are required to establish their industrial feasibility.