Factors affecting the yield and properties of bacterial cellulose

• Published in: Journal of industrial microbiology & biotechnology Vol. 29; no. 4; pp. 189 - 195
• Main Authors: KRYSTYNOWICZ, A, CZAJA, W, WIKTOROWSKA-JEZIERSKA, A, GONCALVES-MISKIEWICZ, M, TURKIEWICZ, M, BIELECKI, S
• Format: Journal Article
• Language: English
• Published: Heidelberg Springer 01-10-2002; Oxford University Press
• Subjects: Acetobacter - genetics; Acetobacter - growth & development; Acetobacter - metabolism; Bacteria; Biochemistry; Biological and medical sciences; Biopolymers; Bioreactors; Biotechnology; Cellulose; Cellulose - biosynthesis; Cellulose - chemistry; Colony Count, Microbial; Culture Media - chemistry; Ethanol; Fermentation; Fundamental and applied biological sciences. Psychology; Hydrogen-Ion Concentration; Investigations; Mechanical properties; Microbiology; Oxygen; Physical properties; Studies
• ISSN: 1367-5435; 1476-5535
• DOI: 10.1038/sj.jim.7000303

Acetobacter xylinum E(25) has been applied in our studies in order to find optimal culture conditions for effective bacterial cellulose (BC) production. The strain displays significantly higher stability in BC production under stationary culture conditions. In contrast, intensive agitation and aeration appear to drastically reduce cellulose synthesis since such conditions induced formation of spontaneous cellulose nonproducing mutants (Cel-), which dominated in the culture. Mutation frequency strictly depends on the medium composition in agitated cultures. Enrichment of the standard SH and Yamanaka media with 1% ethanol significantly enhanced BC production in stationary cultures. Horizontal fermentors equipped with rotating discs or rollers were successfully applied in order to improve culture conditions. Relatively slow rotation velocity (4 rpm) and large surface area enabling effective cell attachment are optimal parameters for cellulose production. Physical properties of BC samples synthesized either in stationary cultures or in a horizontal fermentor revealed that cellulose from stationary cultures demonstrated a much higher value of Young's modulus, but a much lower value of water-holding capacity.