Effect of Nutritional Conditions on the Fermentative Production of Pyruvic Acid by Torulopsis glabrata
营养条件对光滑球拟酵母发酵生产丙酮酸的影响

The effects of some nutritional conditions,such as peptone concentration,feeding glucose as well as oxygen supply manner and ratio of C/N in batch culture,on the fermentative production of pyruvic acid by Torulopsis glabrata WSH-IP12 were investigated.In shaking flask culture:(1)peptone of more than 20 g/L inhibited the accumulation of pyruvic acid;(2)production of pyruvic acid was increased from 23.5 g/L to 30.2 g/L by simply feeding glucose.In 5 L jar fermentor batch culture:(1)high level of dissolved oxygen and (2)increasing the concentration of glucose and peptone proportionally with constant C/N ratio(26:1)improved the production of pyruvic acid.It was also found that,glucose consumption and pyruvic acid production almost stopped under the condition of nitrogen difficiency while recovered by adding peptone and (NH 4) 2SO 4.By using ammonia water instead of potassium hydroxide for the control of pH,the cells kept stronger ability for synthesizing pyruvic acid within the whole process,57.3 g/L pyruvic acid with the yield of 0.498 g/g was achieved at 55 h of fermentation.