The Effects of Agitation on Saccharomyces cerevisiae Yeast Carbon Dioxide Output

Chase Jedele, Carlye Kennedy, Seabring Huckleberry, Wyatt Hinson, Rachel Hamrock


Baker’s yeast (Saccharomyces cerevisiae) is used in the commercial production of goods, and could potentially be a new source of biofuel, isobutanol. Agitation is crucial to the production of CO2 output from yeast cells in a solution. Therefore, as agitation levels increase, CO2output will increase as well. The biochamber, which contains a yeast solution, was agitated by stirring at four different levels. Using a CO2 probe, we were able to measure the output from the agitated yeast solution for seven minutes per trial. After all trials were completed, the CO2 output increased steadily as agitation levels rose. Eventually, the CO2 output plateaued at around 900 ppm. After analyzing the results, we found our hypothesis to be supported as agitation levels increased. Although our experiment is on a much smaller scale, the results are promising in a much larger experiment, which could lead to the production of biofuels from yeast fermentation. 

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