XYLOSE REDUCTASE PRODUCTION BY CANDIDA-GUILLIERMONDII

The effect of pH, time of fermentation, and xylose and glucose concent ration on xylitol production, cell growth, xylose reductase (XR), and xylitol dehydrogenase (XD) activities of Candida guilliermondii FTI 20 037 were determined. For attaining XR and XD activities of 129-2190 U/ mg of protein and 24-917 U/mg of protein, respectively, the cited para meters could vary as follows: initial pH: 3.0-5.0; xylose: 15-60 g/L; glucose: 0-5 g/L; and fermentation time: 12-24 h. Moreover, the high X R and XD activities occurred when the xylitol production by the yeast was less than 19.0 g/L.