Effect of High-glucose Condition on Antioxidant Activity and Metabolism of Saccharomy cescerevisiae

In this paper,Saccharomyces cerevisiae was used as model organism to study the effects of high glucose culture on the growth,antioxidant enzyme activities andtrehalose and glycerol metabolism of Saccharomyces cerevisiae. The results showed that,when the glucose concentration reached 40%,the logarithmic phase of S.cerevisiae growth was prolonged,which inhibited the growth of S. cerevisiae. The accumulation of trehalose showed significant changes with the increasing of stress time(P<0.05),the accumulation of trehalose increased first and then decreased in the four groups of Saccharomyces cerevisiae cells(20 g/L glucose group,40 g/L glucose group,60 g/L glucose group and 80 g/L glucose group)in the range of 4~10 h culture. The accumulation of trehalose in the high sugar group reached a highest point with 95.5 mg/mL intracellular trehalose at 8 h culture. Under the stress of different glucose concentrations,the accumulation of glycerol in yeast cells increased first and then decreased with time up,but the accumulation of intracellular glycerol reached the highest at 80 g/L glucose,while the accumulation of extracellular glycerol reached the highest at 60 g/L glucose. These results indicated that glycerol and trehalose were the main compatible solutes of S. cerevisiae under high sugar stress. In addition,after high glucose treatment,S. cerevisiae superoxide of dismutase(SOD),catalase(CAT)and glutathione peroxidase with high glucose group were significant higher than the control group. It indicated that these antioxidant enzymes play a key role in maintaining the intracellular normal osmotic pressure. The results of this study would provide a theoretical basis for the future study of S. cerevisiae resistance to high glucose osmotic pressure.