Yeast Biotechnology

Optimization of Ethanol Production using Nitrosative Stress Exposed S.cerevisiae

S.cerevisiae is an industrially important organism known for its ability to produce ethanol as the demand for ethanol is increasing day by day all over the world, the need to find better and alternative ways to increase ethanol production is also rising. In this work we have proposed such alternative but effective method for producing ethanol by S.cerevisiae. Here, we are reporting for the first time the effect of nitrosative stress on ethanol production. Under in vivo condition, nitrosative stress is marked by the modification of macromolecules in the presence of reactive nitrogen species (RNS). Our result showed that treated cells were more capable for ethanol production compared with untreated cells. Our result also showed enhanced alcohol dehydrogenase activity under stressed condition. Further ethanol production was also optimized by using Response Surface Methodology (RSM) with stressed cells. Further, production of ethanol with immobilized beads of stress affected Saccharomyces cerevisiae was also determined. Overall, the obtained data showed that under nitrosative stress, the maximum ethanol production is 34.4 g/l after 24 h and such higher production was observed even after several cycles of fermentation. This is the first report of this kind showing the relation between nitrosative stress and ethanol production in Saccharomyces cerevisiae which may have important industrial application.