Репозиторий Университета

© 2020 Elsevier Ltd In this paper, we perform a systematic analysis of the structural organization of bacterial cellulose (BC). We report four types of organization of the BC mass, produced by Gluconacetobacter hansenii that occur depending on cultivation conditions. Two of those, particularly, plywood type one and layers of micro-sized tubes were observed and described for the first time. In spherical BC particles (pellets), we found the layered structure that had previously been reported for planar geometry only. We suggest a model explaining why layers form in BC films and attempt to reveal the impact of different factors on the BC microscale morphology. We assume that the main factor that has direct impact on the type of structure formed is the rate of BC mass accumulation.

© 2020 Elsevier Ltd In this paper, we perform a systematic analysis of the structural organization of bacterial cellulose (BC). We report four types of organization of the BC mass, produced by Gluconacetobacter hansenii that occur depending on cultivation conditions. Two of those, particularly, plywood type one and layers of micro-sized tubes were observed and described for the first time. In spherical BC particles (pellets), we found the layered structure that had previously been reported for planar geometry only. We suggest a model explaining why layers form in BC films and attempt to reveal the impact of different factors on the BC microscale morphology. We assume that the main factor that has direct impact on the type of structure formed is the rate of BC mass accumulation.

© 2020 Elsevier Ltd In this paper, we perform a systematic analysis of the structural organization of bacterial cellulose (BC). We report four types of organization of the BC mass, produced by Gluconacetobacter hansenii that occur depending on cultivation conditions. Two of those, particularly, plywood type one and layers of micro-sized tubes were observed and described for the first time. In spherical BC particles (pellets), we found the layered structure that had previously been reported for planar geometry only. We suggest a model explaining why layers form in BC films and attempt to reveal the impact of different factors on the BC microscale morphology. We assume that the main factor that has direct impact on the type of structure formed is the rate of BC mass accumulation.

© Copyright 2018 Inderscience Enterprises Ltd. This paper is concerned with the studies of a natural nanomaterial which is bacterial cellulose synthesised by Gluconacetobacter hansenii producer strain. It covers different fields of bacterial cellulose use, including medicine. The research has proved that bacterial cellulose matrices with immobilised cells have high potential as immobilisers of cells, including making probiotics of prolonged action. The matrices consisted of bacterial cellulose films were prepared by static cultivation of G. hansenii GH-1/2008 strain in the liquid medium. We have developed methods of washing out end toxins and producer cells of the films in the solutions of sodium bicarbonate, sodium dodecyl sulphate, and sodium hydroxide. The LAL-test has revealed that washing the films with sodium dodecyl sulphate is more efficient. By means of electron scanning and atomic force microscopy (AFM), we have determined that bacterial cellulose matrices have a layered structure, smooth surface, and adhesion of E. coli test strain cells. The adhesive capacity, the energy of adhesion and contact angle is higher for 50 um thick films than for 20 um thick ones. The bacterial cellulose matrices obtained by the biosynthesis of G. hansenii strain can be recommended for the immobilisation of different producer cells.