2017 年 23 巻 6 号 p. 793-800
This study investigated the production of erythritol by Trichosporonoides oedocephalis in response to the varying osmotic pressure. Osmotic pressure was exerted by adding NaCl or KCl into the fermentation broth. It was demonstrated that appropriate raise in osmotic pressure enhanced erythritol production, wherein 5 g/L KCl addition increased erythritol yield by 44.21% compared to the control. The reason for the significant increase in the erythritol production showed that the 5 g/L KCl addition accelerated the glucose utilization in the late period of fermentation time. It was also revealed that 5 g/L KCl increased the activity of erythrose reductase (ER) in the same fermentation period. In bioreactor, the erythritol yield with initial 5 g/L KCl addition was up to 50.54 g/L, which was 47.69% higher than the control (34.22 g/L). The study provided a novel fermentation regulation, that is, economical addition of KCl made more effective production of erythritol when using T. oedocephalis.