Mechanism of Fermentation Conversion from Polyalcohol Fermentation to Ethanol Fermentation byPichia miso

A possible mechanism of fermentation conversion is described from polyalcohol fermentation to ethanol fermentation by Pichia miso. Little alcohol dehydrogenase activity was found in polyalcohol-producing cells, whereas higher enzyme activity was induced by ethanol-producing cells. The fermentation conversion may be caused by the different levels of alcohol dehydrogenase activity between polyalcohol- and ethanol-producing cells. It was also shown that yeast growth was inhibited and that yeast cells were lysed by ethanol (at 6g/100ml) that accumulated in 24 hr.