Effects of Long-Term Cultivation on Medium with Alpha-Ketoglutarate Supplementation on Metabolic Processes of Saccharomyces cerevisiae

During last years,alpha-ketoglutarate (akg),an important intermediate in the krebs cycle,has been intensively studied as a dietary supplement with stress-protective and potential antiaging effects. here,we examined the effects of exogenous akg on metabolic processes and survival of yeast saccharomyces cerevisiae during long-term cultivation. growth on akg had no effect on the total cell number but increased the number of reproductively active cells at the late days of cultivation (from day 7 to day 15). a gradual increase in levels of total protein,glycogen,and trehalose was found over 7-day cultivation with more pronounced effects in akg-grown cells. in control cells,metabolic activity and the activities of superoxide dismutase and catalase decreased,whereas levels of carbonyl proteins and low-molecular-mass thiols increased during 7-day cultivation. this suggests development of oxidative stress in stationary phase cells. meanwhile,stationary phase cells cultured on akg possessed higher levels of low-molecular-mass thiols and lower levels of carbonyl proteins and α-dicarbonyl compounds when compared to control ones. collectively,higher levels of storage carbohydrates and an activation of antioxidant defense with diminishing oxidative protein damage can prevent a loss of reproductive ability in yeast cells during long-term cultivation on akg-supplemented medium. © 2017 nadia burdyliuk and maria bayliak.