Effect of Nutrient Medium Composition on Bacterial Cellulose: Yield and Physicochemical Profile

Bacterial cellulose differs from plant cellulose: its unique properties include a strong crystalline nanostructure and a high degree of polymerization. In addition, it is more pure than traditional cellulose as it contains neither lignin nor hemicellulose. These qualities make it a promising alternative to plant cellulose in several industries. Bacterial cellulose with the specific physicochemical profile can be obtained only if the metabolizing properties of its producer have been considered. This article describes the effect of nutrient medium compositions with different carbon sources, vitamins, mineral salts, and acids on the yield and properties of bacterial cellulose. Acetic acid bacteria Acetobacterium xylinum B-12429 were cultivated statically at 28°C for 72 h on the Hestrin-Schramm medium with varying carbon sources and growth factors. The highest biomass yield (4.4 g/L) was obtained on cultivation day 10 in the sample with 20.0 g/L fructose. Glucose provided a lower productivity of 3.6 g/L. The bacterial cellulose yield also proved to depend on the concentration of the main carbon source: it was at its maximum at 10%. Adding ascorbic acid and MgSO4 also catalyzed the biosynthesis. The structural profile was studied using infrared spectroscopy and scanning electron m icroscopy. It included such physicochemical properties as water-holding capacity and crystallinity indices Iα and Iβ. The biofilms produced from the media fortified with xylose and sorbitol demonstrated excellent water-holding capacity; all the samples demonstrated a stable crystalline structure regardless of the carbon source. The composition of the nutrient media had a significant effect on the yield and quality of biosynthesis. An optimized nutrient composition was able to boost biosynthesis, making the method applicable to industrial scales of high-quality bacterial cellulose production.