Intracellular trehalose metabolism characteristics of Zygosaccharomyces rouxii under different stresses

Trehalose content and the resistance of yeast are positively correlated,the content of intracellular trehalose is an important index for assessing the quality and the activity of active dry yeast. The intracellular trehalose synthesis regulation of Zygosaccharomyces rouxii under osmotic pressure,temperature,ethanol and H₂O₂ was discussed. The study showed that the osmotic pressure had no obvious effect on trehalose accumulation.Trehalose content was lower under high concentrations of Na Cl stress,but adding ethanol and raising temperature were conducive to the accumulation of trehalose: trehalose content was increased by 9.09%from 20.46 mg/g Dw to 22.32 mg/g Dw at 9 h after ethanol added and trehalose content was increased by 39.14%from 17.55 mg/g Dw to 24.41 mg/g Dw at 6 h for heating.During the early period under H₂O₂ stress,0.2% H₂O₂ can enhance the accumulation of trehalose remarkablely. Compared with the control content of 8.17 mg/g Dw,the trehalose was increased by 73.56% to the content of 14.18 mg/g Dw.This result had certain guiding significance for soy sauce fermentation and improving soy sauce storage stability of active dry yeast.