Screening for Optimal Algal Cell Growth and Neutral Lipid Production Conditions in Microplates

This posters describes the quantitation of algal cell growth under various growth media conditions using a microplate reader to make absorbance and fluorescent determinations. Light scatter absorbance measurements at 600 nm were used to monitor cell growth and Nile Red stain fluorescence monitored neutral lipid production under various nutrient deficient states. Algal cells grow to a 20-fold greater density in complete nutrient rich media than in either nutrient poor or nitrogen deficient media. However, despite the marked disparity in cell number, cultures grown in nitrogen deficient media exhibit more neutral lipid staining. On a per cell basis Chlorella vulgaris cultures grown in nitrogen deficient media have 15-fold more lipid than cells grown in complete media. When nutrient deprived cells are placed in complete media, lipid droplets are quickly reabsorbed and Nile red staining returns to basal levels. The use of microplates enables the rapid measurement of multiple samples and experimental conditions at the same time.