Sorbitol and gluconic acid production using permeabilized Zymomonas mobilis cells confined by hollow-fiber membranes

• Published in: Applied biochemistry and biotechnology 2000-10, Vol.89 (1), p.43-53
• Main Authors: Ferraz, H.C, Borges, C.P, Alves, T.L.M
• Format: Article
• Language: English
• Subjects: Acid production; Acids; Alginates; Bacteria; Biochemistry; Biological and medical sciences; Biotechnology; Biotechnology - instrumentation; Biotechnology - methods; calcium alginate; Cell Membrane Permeability; Cells; Cells, Immobilized - metabolism; Enzymatic activity; enzyme activity; Fundamental and applied biological sciences. Psychology; gels; Gluconates - metabolism; gluconic acid; Glucuronic Acid; Hexuronic Acids; immobilized cells; Kinetics; Mass transfer; Membranes, Artificial; Methods. Procedures. Technologies; Microbial engineering. Fermentation and microbial culture technology; porous media; Proteins; sorbitol; Sorbitol - metabolism; Studies; Zymomonas - metabolism; Zymomonas mobilis
• ISSN: 0273-2289; 1559-0291; 0273-2289
• DOI: 10.1385/abab:89:1:43

Immobilization of Zymomonas mobilis by different methods was investigated. Experiments were performed in order to choose the most appropriate support for the immobilization of the cells. The most advantageous option was to use permeabilized cells in the bore of microporous hollow fibers. Whereas the reaction rate was about 33 g of gluconate/(g of protein(.)h) using hollow fibers, which is comparable to that observed by using free cells, the calcium alginate immobilized cells presented a reaction rate of 4 g of gluconate/(g of protein(.)h). These results can be explained by the mass transfer resistance effect, which indeed, was much lower in the case of hollow-fiber membranes than in the alginate gel beads. A loss of enzymatic activity during the reaction was observed in all experiments, which was attributed to the lactone produced as an intermediate of the reaction.