Bacterial Cellulose Film Used In A Preliminary Study Of Immobilized Microbial Cells And Reproducing Film

Bacterial cellulose obtained from fermentation by the Acetobacter xylinum is of superior properties in comparison with plant cellulose. Bacterial cellulose has been used for a variety of applications due to its particular network structure, high purity, high crystallinity, high Young's modulus and biodegradability. The preliminary application in immobilization of microorganism and acoustic diaphragms were investigated.Application of bacterial cellulose membrane in immobilization carrier of Phanerochaete chrysosporium and white rot fungi Z-4 were investigated by adopting the methods of static culture and shake flask culture respectively. The inoculation method, inoculation time for the static culture and the carrier size and amount for the shake flask culture were studied respectively. The preferable immobilization effect for the Phanerochaete chrysosporium and white rot fungi Z-4 were obtained. And the experiments of degrading malachite green with immobile Phanerochaete chrysosporium and white rot fungi Z-4 were investigated. Comparing with free cells, immobilization not only increased the ability to decolorize dye but also kept the stable rate of decolorization in the condition of different culuture medium pH values and dye concentrations. The differences of spectra assay showed that the absorption in visible range disappeared. And the result indicated that the structures of dyes had changed. The bacterial cellulose showed its favorable properties in immobilization carrier.A new apparatus for measuring the dynamic Young's modulus and internal loss is designed. The dynamic Young's modulus and internal loss of static culture and shake flask culture membranes has been measured. The highest Young's modulus 27.9846 GPa was obtained using the static culuture method and dried with oven.The sonic velocity and the internal loss were 4714.8 m·s^-1 and 0.0552 in this method. However, the dynamic Young's modulus decreased about 50% when the membranes obtained from shake flask culture and hot-press method. By virtue of its high dynamic Young's modulus and high internal loss, the bacterial cellulose sheet is expected to be useful for acoustic diaphragms.