Effect of lyophilization on the bacterial cellulose produced by different Komagataeibacter strains to adsorb epicatechin.

Bacterial cellulose (BC) has been widely used as a model system to investigate the interaction of polyphenols with the polysaccharides of cell walls. In this study, the water absorption ability and the adsorption ability of epicatechin of the never-dried and freeze-dried BC produced by a high-yield Komagataeibacter hansenii strain ATCC 53582 was compared with two normal-yield strains. The structural characteristics of BC were investigated via microscopy observation and mechanical/rheological tests. The 1-butyl-3-methylimidazolium acetate/dimethyl sulfoxide ([BMIM]Ac/DMSO) co-solvent was used to dissolve BC to calculate the degree of polymerization (DP). Results showed that compared with the other two strain, the BC synthesised by ATCC 53582 had a higher cellulose concentration (1.2 wt%) but lower epicatechin adsorption (29 μg/mg under 4 mM, pH 7). Its fibril network collapsed and led to a reduced recovery ratio (86 %) in the compression-relaxation test, which may be due to large DP (2856).