Kinetics of xylitol fermentation by Candida guilliermondii grown on rice straw hemicellulosic hydrolysate
Roberto, I.; Mancilha, I.-De; Sato, S.
Applied biochemistry and biotechnologyng 77(77-79): 205-210
The fermentation kinetics for the conversion of rice straw hemicellulosic hydrolysate to xylitol by the yeast Candida guilliermondii was evaluated under batch conditions. The fermentation was accomplished in a 1 L working volume stirred-tank reactor with aeration of 1.3 vvm and agitation of 300 rpm (kLa = 15/h). The maximum specific rate of xylitol formation (0.12 g/g) was achieved when the specific growth rate was lowered to 1/5 of its highest value. From analysis of the fermentation kinetics, a linear correlation between specific growth rate (micro x) and specific rate of xylitol formation (qp) was evident. Based on the Gaden model, this bioprocess was classified as growth-associated production and the relationship between micro x and qp can be described by the equation qp = 6.31 micro x.