Abstract
We developed a novel cultivating system for hollow-type spherical bacterial cellulose (HSBC) gel production without any molds or template. It consisted of floating aqueous medium droplet containing Gluconacetobacter xylinus (G. xylinus) at the boundary of two non-mixed silicone oil layers. The fibrils of bacterial cellulose (BC) were produced at the interface of water and oil phases. Fibril layers effectively thickened layer-by-layer and eventually formed a shell structure. The size of the HSBC gel can be controlled by the volume of dropped cell suspension. For cell suspensions of 50 μL and 10 μL, HSBC gels of approximately 4.0 mm and 2.5 mm were obtained, respectively. The shell of the HSBC gel is the gelatinous membrane formed by well-organized fibril networks; they comprised type-I crystal structure of cellulose. Additionally, we studied release profile of the fluorescein isothiocyanate-dextran (FITC-Dex) and observed that it released rapidly from the HSBC gels compared to from the BC gels obtained by the static culture method. The release behavior from HSBC gel agreed satisfactorily with Higuchi model. Therefore, the shell of HSBC gel is surely a thin gelatinous membrane of BC, and would be useful as a drug release device.
Highlights
The most abundant renewable biopolymer is cellulose, a polysaccharide consisting of linear b-1,4-D-glucose units
The size of the hollow-type spherical bacterial cellulose (HSBC) gel can be controlled by the volume of dropped cell suspension
Preparation of spherical Bacterial cellulose (BC) gels was predicted by culturing G. xylinus in medium droplets. We hypothesized that it would be hollow-type spherical BC, that can have thin gelatinous membrane composed of cellulose networks, which would be produced at the interface of water and oil phases
Summary
The most abundant renewable biopolymer is cellulose, a polysaccharide consisting of linear b-1,4-D-glucose units. Its shape depends on that of the culture container Another method is agitated culture, using which, cellulose having a fibrous structure dispersed throughout the medium was synthesized (Chao et al, 2000; Watanabe et al, 1998). Under certain agitated culture conditions, Acetobacter xylinum strain NQ5 (ATCC 53582) produced isolated sphere-type cellulose (Czaja et al, 2004). As unique shape of the BC gel, tubular BC is reported by two different methods. We hypothesized that it would be hollow-type spherical BC (as HSBC), that can have thin gelatinous membrane composed of cellulose networks, which would be produced at the interface of water and oil phases. To the best of our knowledge, there is no report about such HSBC gel and the culturing method. These HSBC gels are expected as a seamless capsule for drug delivery applications
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
