Specific features of fermentation of D-xylose and D-glucose by xylose-assimilating yeasts

The ability to assimilate D-glucose and D-xylose was studied in 21 yeast species of the following genera: Candida, Kluyveromyces, Pachysolen, Pichia, and Torulopsis. All the cultures fermented D-glucose with the formation of ethanol. During the assimilation of D-xylose, ethanol was produced by P stipitis and C shehatae, whereas xylitol was produced by C didensiae, C intermediae, C parapsilosis, C silvanorum, C tropicalis, K. fragilis, K. marxianus, R guillermondii, and T molishiama. The yeast P tannophilus produced comparable amounts of both alcohols. The possible use of xylose-assimilating yeasts for the production of xylitol and ethanol is discussed.