EFFECTS OF CULTURE CONDITIONS ON FERMENTATION OF PENTOSE BY PICHIA STIPITIS

Effects of culture condition,including nitrogen source,pH value and temperature on pentose(mainly (xylose)) fermentation by Pichia stipitis P_2 were investigated.Both growth and xylose fermentation were as good with (urea) as a sole nitrogen source as with peptone as a sole nitrogen source.The optimum pH value and temperature range of the growth of Pichia stipitis P_2 were 4.6-5.8 and 25-30 ℃,respectively.When cultural temperature was 25 ℃ and 35 ℃,the optimum pH value range of the xylose fermentation by P_2 was 3.4-4.2 and 3.8-5.0,respectively.