The effect of salinity stress on cell count of Saccharomyces cerevisiae

  • Katerena Goston
  • Eric K. Jeong
  • Cynthia C. Lung
  • Serena S. Wang


Saccharomyces cerevisiae can live in a variety of stressful environments, including varying salinities, making it an ideal model organism to test effects of NaCl concentrations on growth rate. Our experiment was carried out over a nine-hour period and was started by diluting the prepared sample of 400μL of 4M NaCl in YPD into three group concentrations, with four test tubes in each group: 0M NaCl, 1M NaCl and 2M NaCl, with a total of 12 test tubes incubated at 35°C water bath.  After increments of 90 minutes, 100μL from each test tube was pipetted into a micro centrifuge tube, in addition to 10μL fixative for further analysis under the microscope. The initial cell count was 3.34 x 105 cells, 3.12 x 105 cells, and 2.81 x 105 for 0M, 1M and 2M NaCl, respectively. The control group experienced a rapid cell proliferation with the final cell count as 9.80 x 106 cells. In contrast, 1M and 2M did not experience similar cell division with the final count as 9.46 x 105 cells and 3.10 x 105 cells respectively. The results suggest that exposure to 1M and 2M NaCl concentrations impair cellular functions and higher salinity has a negative impact on cell count.