Scale-Up of Biosynthesis Process of Bacterial Nanocellulose

Abstract

Bacterial nanocellulose (BNC) is a unique product of microbiological synthesis, having a lot of applications among which the most important is biomedicine. Objective complexities in scaling up the biosynthesis of BNC are associated with the nature of microbial producers for which BNC is not the target metabolite, therefore biosynthesis lasts long, with the BNC yield being small. Thus, the BNC scale-up problem has not yet been overcome. Here we performed biosynthesis of three scaled sheets of BNC (each having a surface area of 29,400 cm2, a container volume of 441 L, and a nutrient medium volume of 260 L and characterized them. The static biosynthesis of BNC in a semisynthetic nutrient medium was scaled up using the Medusomyces gisevii Sa-12 symbiotic culture. The experiment was run in duplicate. The BNC pellicle was removed once from the nutrient medium in the first experiment and twice in the second experiment, in which case the inoculum and glucose were not additionally added to the medium. The resultant BNC sheets were characterized by scanning electron microscopy, capillary viscosimetry, infrared spectroscopy, thermomechanical and thermogravimetric analyses. When the nutrient medium was scaled up from 0.1 to 260 L, the elastic modulus of BNC samples increased tenfold and the degree of polymerization 2.5-fold. Besides, we demonstrated that scaled BNC sheets could be removed at least twice from one volume of the nutrient medium, with the yield and quality of BNC remaining the same. Consequently, the world’s largest BNC sheets 210 cm long and 140 cm wide, having a surface area of 29,400 cm2 each (weighing 16.24 to 17.04 kg), have been obtained in which an adult with burns or vast wounds can easily be wrapped. The resultant sheets exhibit a typical architecture of cellulosic fibers that form a spatial 3D structure which refers to individual and extremely important characteristics of BNC. Here we thus demonstrated the scale-up of biosynthesis of BNC with improved properties, and this result was achieved by using the symbiotic culture.

Simultaneous Production of Cellulose Nitrates and Bacterial Cellulose from Lignocellulose of Energy Crop

“…The morphology of the BC samples synthesized on synthetic nutrient medium (control) and enzymatic hydrolyzates was investigated by SEM ( Figure 5 ). The overall morphological structure of the BC samples exhibited an intertwined network of microfibrils with inter-fibrillar spaces, consistent with the structure of BC samples reported in the literature [ 46 , 94 , 95 ]. The width of the microfibrils for the BC sample synthesized on the synthetic nutrient medium (control) ranged from 26.0 nm to 229.0 nm, with an average width of 58.0 nm.…”

“…There are examples of hydrolyzates derived from Miscanthus [ 32 , 45 ]. Additionally, there is a need to upscale the biosynthesis process to ensure sufficient amounts of the precursor for promising CNs [ 46 ], but studies of this kind are scarce.…”

Static Culture Combined with Aeration in Biosynthesis of Bacterial Cellulose

“…The BC yield was calculated by Equation (1), where the BC yield was estimated as the quantity of the resultant dry BC with respect to the initial concentration of the carbon source–glucose: where η is the BC yield, %; m BNC is the BC sample weight on an oven-dry basis (g), C g is the glucose concentration in the medium (g/L), V is the medium volume (L), and 0.9 is the conversion coefficient attributed to the water molecule detachment upon polymerization of glucose into cellulose. The yield was calculated by the procedure reported [ 30 ].…”

The Development of a Bacterial Nanocellulose/Cationic Starch Hydrogel for the Production of Sustainable 3D-Printed Packaging Foils

“…Polymers 2024, 16, 1527 2 of 23 defines nanomaterials as substances with 50% or more of the particles having one of the outer dimensions in the range 1 nm-100 nm [7].…”