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Bacterial cellulose (BC) is a unique biopolymer synthesised by many bacteria as a critical element of their biofilm matrix. The most known and efficient producers of BC are bacteria from the genus of Komagataeibacter. Bacterial cellulose, with its unique properties, high crystallinity, mechanical strength, and unprecedented ability to hold water, is an object of interest in many industries. Despite the enormous efforts that have been made to develop an effective process, the economic aspect of BC production is still a limiting factor for broadening applications, and new “breaking point” solutions are highly anticipated. In this study, the possibility of using sucrose, lactose, and starch as alternative carbon sources converted to simple sugars directly in the culture medium by microbial glycohydrolases, β-D-fructofuranosidase, β-galactosidase, and glucoamylase in the process of BC synthesis was analysed. The results showed the high potential of the enzyme-assisted fermentation process that, for most used raw carbons sources, was highly efficient, with a yield higher (i.e., lactose 40% more) or comparable to the cultures maintained on standard Hestrin-Schramm media with glucose as a sole carbon source. The X-ray diffraction, Fourier transform infrared spectroscopy, and scanning electron microscope analyses did not reveal any negative influence of enzyme-assisted cultivation on the BC material properties, such as crystallinity, swelling ratio, and moisture content. Applying specific enzymes for converting inaccessible, raw-form carbon sources to the culture medium of Komagateibacter xylinus opens a simple way to use various oligo- and polysaccharides acquired from many kinds of biomass sources in the BC production process.

Bacterial biofilms generally contribute to chronic infections, including wound infections. Due to the antibiotic resistance mechanisms protecting bacteria living in the biofilm, they are a serious problem in the wound healing process. To accelerate the wound healing process and avoid bacterial infection, it is necessary to select the appropriate dressing material. In this study, the promising therapeutic properties of alginate lyase (AlgL) immobilised on BC membranes for protecting wounds from Pseudomonas aeruginosa infection were investigated. The AlgL was immobilised on never dried BC pellicles via physical adsorption. The maximum adsorption capacity of AlgL was 6.0 mg/g of dry BC, and the equilibrium was reached after 2 h. The adsorption kinetics was studied, and it has been proven that the adsorption was consistent with Langmuir isotherm. In addition, the impact of enzyme immobilisation on bacterial biofilm stability and the effect of simultaneous immobilisation of AlgL and gentamicin on the viability of bacterial cells was investigated. The obtained results showed that the AlgL immobilisation significantly reduced the amount of polysaccharides component of the P. aeruginosa biofilm. Moreover, the biofilm disruption by AlgL immobilised on BC membranes exhibited synergism with the gentamicin, resulting in 86.5% more dead P. aeruginosa PAO-1 cells.

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Bacterial cellulose is a unique biopolymer that has found numerous biomedical applications, such as being an excellent wound-dressing material or a carrier for delivering active compounds. The purpose of this study was to analyze the ability of modified bacterial cellulose (BC) using low-pressure Ar plasma to control the release of glycoside hydrolases with antibiofilm activity, namely PelAh and PslGh, from Pseudomonas aeruginosa. The chemical composition and morphology of the BC surfaces were characterized using photoelectron spectroscopy (XPS), Fourier transform infrared spectroscopy (FTIR), and scanning electron microscopy (SEM). The analyses revealed significant changes in the chemical composition of the BC surface due to the introduction of charged functional groups and the conversion of its well-ordered structure into a more amorphous form. The release profiles of enzymes from both forms of the carrier were different and depended on their structural properties. However, a significant impact of BC modification on protein release behavior from the carrier was observed only for PslGh. Both enzymes, when immobilized on pristine and argon plasma-modified BC, retained their ability to effectively reduce biofilm levels, similarly to their soluble form. Ar plasma-modified BC with immobilized specific hydrolases can be used as an effective tool for inhibiting P. aeruginosa biofilm development.