Improvement in xylitol production from sugarcane bagasse hydrolysate achieved by the use of a repeated-batch immobilized cell system.

Candida guilliermondii cells were immobilized in Ca-alginate beads and used for xylitol production from concentrated sugarcane bagasse hydrolysate during five successive fermentation batches, each lasting 48 hours. The bioconversion efficiency of 53.2%, the productivity of 0.50 g/l x h and the final xylitol concentration of 23.8 g/l obtained in the first batch increased to 61.5%, 0.59 g/l x h and 28.4 g/l, respectively, in the other four batches (mean values), with variation coefficients of up to 2.3%.