Improved xylitol production with Debaryomyces hansenii Y-7426 from raw or detoxified wood hydrolysates

Xylose solutions obtained by acid prehydrolysis of raw or NaOH-treated Eucalyptus globulus wood samples were used for making fermentation media useful for xylitol production with Debaryomyces hansenii NRRL Y-7426. Several physicochemical treatments for detoxification of hydrolysates were rested including overliming, sulfite addition, adsorption in charcoal, and concentration by evaporation. Despite the relatively low xylose concentration of hydrolysates, high xylitol yields (up to 0.84 g xylitol g(-1) consumed xylose) were obtained at good productivities (up to 0.53 g xylitol l-(1)h(-1)). The improvements obtained with the several strategies assayed are discussed in terms of overall productivities and product yield. (C) 1997 by Elsevier Science Inc.