Nitrogen supplements such as yeast extract and peptone/tryptone are the main cost drivers in bacterial cellulose (BC) fermentation. This study evaluated fourteen cereal, pseudo-cereal and legume flours as media substitutes for Komagataeibacter xylinus DSMZ 2325 using two strategies: (i) constant total nitrogen (CTN; 0.6 g·L−1) and (ii) constant nitrogen-source mass (CNSM; 5.0 g·L−1). BC yield (dry g·L−1) was determined under static cultivation and analyzed by ANOVA, correlation statistics and techno-economic assessment. Flour type and substitution level significantly influenced BC production (p < 0.05). CTN substitution enhanced production, with the highest peak yields obtained for W-BC, C-BC, M-BC and SP-BC (6.68–8.97 g·L−1). CNSM substitution limited production, with O-BC and T-BC performing best (4.24–5.14 g·L−1). Techno-economic analysis further showed that the CTN regime substantially improved cost efficiency and reduced BC unit production cost, with the maximum reduction observed for TR-BC at 75% substitution (from 0.27 to 0.08 €/g; 70.37%) relative to the corresponding CTN HS control. Under the CNSM regime, the maximum reduction was observed for BY-BC at 50% substitution (from 0.25 to 0.07 €/g; 72.00%) relative to the corresponding CNSM HS control. These findings demonstrate that graded nitrogen substitution is an effective strategy for economically sustainable and scalable BC production.
Absharina et al. (Mon,) studied this question.