Impact of Fermentation Conditions and Purification Strategy on Bacterial Cellulose Properties

Abstract

Bacterial cellulose (BC) has attracted much research interest, delivering a combination of exclusive properties, such as flexibility, hydrophilicity, crystallinity and a three-dimensional network. In this study, the effects of carbon source and cultivation conditions on BC production by the bacterium Acetobacter xylinum subsp. sucrofermentans DSM 15973 were assessed. Fructose was the most suitable carbon source and high BC concentrations up to 31 g l–1 were achieved in substrates with 60 g l–1 fructose under static culture conditions. Notably, BC production was equally high under the same fermentation conditions in agitated cultures (~30 g l–1). Moreover, the effectiveness of sodium hydroxide and sodium hypochlorite solutions in BC purification and their potential impact on BC structure and properties were explored. The combination of weak NaOH and NaOCl proved an effective purification method, preserving the fibre structure and crystallinity of BC.