Improved production of bacterial cellulose through investigation of effects of inhibitory compounds from lignocellulosic hydrolysates

Abstract

Although the unique nanostructure of bacterial cellulose (BC) imparts superior mechanochemical properties and thus allows for diverse applications, the high production cost of BC necessitates the development of more cost-effective solutions, for example, those using lignocellulosic biomass as a substrate and relying on its pretreatment and saccharification to generate fermentable sugars. However, the various species (e.g., aliphatic acids, furans, and phenolics) produced during pretreatment may interfere with bacterial cell growth and BC production. Herein, we investigated the effects of aliphatic (acetic and formic) acids, furans (5-hydroxymethylfurfural [5-HMF] and furfural), and phenolics (syringaldehyde and p-coumaric acid) on the production of BC. This production was enhanced at low aliphatic acid concentrations (1 g/L acetic acid and 0.5 g/L formic acid) but was suppressed by at least 90% in cases of 0.75 g/L formic acid, 0.4 g/L furfural, 4 g/L 5-HMF, 2.5 g/L syringaldehyde, and 2.5 g/L p-coumaric acid. BC production efficiencies of 97.86%, 76.66%, and 73.50% were observed for Miscanthus, barley straw, and pine tree hydrolysates, respectively, under optimal conditions. Therefore, these results provided the possibility to utilize the most abundant and sustainable lignocellulose on the planet for BC production.