Deciphering Yeast Transcriptomics: A Unique Tool in Understanding Biochemical Basis for Ethanol Production

Saccharomyces cerevisiae is so crucial to bioethanol production that its performance in ethanol production decides whether a process is economical or not. Biochemical basis of ethanol production appears simple with dosing of yeast to sugar rich medium where yeast produces ethanol through fermentation process. But a closer look gives a much complex process involved in ethanol production. Yeast will be growing in an unfavorable high solid medium in presence of inhibitors such as ethanol and organic acids. Also, there will be mass transfer limitations such as oxygen transfer rates (OTR) and temperature. In order to optimize the ideal conditions for the yeast growth and ethanol production it is critical to understand the yeast behavior at transcriptional level. The present study employed corn stover and other leading cellulosic biomasses for ethanol production in benchtop bioreactor. Samples were harvested at 24, 48 and 72h and analyzed for yeast behavior during fermentation. Transcriptional analysis of yeast indicated stress related genes up-regulation during fermentation. The presentation will discuss transcriptional information of important biochemical pathways as influenced by the fermentation conditions.