Optimization of biosynthesis process of bacterial cellulose membrane using seabuckthorn extract and its application...

This study used seabuckthorn extract (SB) as substrate to enhance the production of bacterial cellulose (BC) membranes by Komagataeibacter rhaeticus (K. rhaeticus), and further used in food preservation. The maximum BC yield (4.76 g/L) was obtained at a 1:1 solid-liquid ratio, pH 6.0, and 15 g/L yeast extract after the solid-liquid ratio, pH, and nitrogen supply were optimized, which exceeding the yield obtained with a commercial glucose-based medium (4.53 g/L). SEM, FT-IR, XRD, TGA, and DSC all verified that the SB/BC membrane had physicochemical characteristics that were comparable to those of traditional HS/BC. The SB/BC composite membrane fabricated using SB extract was enriched with polyphenols and flavonoids, the contents of which increased with the solid-liquid ratio. As a result, the membrane exhibited both antibacterial and antioxidant properties. It demonstrated inhibitory effects against Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus), and the membrane prepared with a 1:1 solid-liquid ratio achieved DPPH and ABTS free radical scavenging rates of up to 90%. Furthermore, the sea bass preservation experiment confirmed that the SB/BC composite membrane effectively suppressed spoilage. Compared to the untreated group and the pure BC group, it significantly reduced the juice loss rate and inhibited the increase in total viable count (TVC), malondialdehyde accumulation, and pH levels. These results suggest that the SB/BC composite membrane is a promising candidate for active packaging to prolong seafood shelf life.