# Techno-Economic and Statistical Assessment of Agricultural Flours for Bacterial Cellulose Production by Komagataeibacter xylinus

## TL;DR

This study explores using agricultural flours to replace costly nitrogen supplements in producing bacterial cellulose, finding that certain flours can significantly reduce production costs.

## Contribution

The paper introduces a novel approach of graded nitrogen substitution using agricultural flours to enhance the cost-efficiency of bacterial cellulose production.

## Key findings

- CTN substitution with specific flours increased BC yields to 6.68–8.97 g·L−1.
- CNSM substitution limited BC production but still achieved cost reductions of up to 72%.
- TR-BC and BY-BC showed the highest cost reductions under CTN and CNSM regimes, respectively.

## Abstract

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.