Biomass Measurement of Microalgae Cultivated under Photoautotrophic Conditions for Biofuels

Linear regression equations for dry cell weight versus optical density (OD680) for 16 strains of microalgae were developed. Carbon contents of the green algae and diatoms were between 40.56–49.62% and 25.74–41.7%, respectively. The ventilation (especially the addition of CO2) and high light intensity significantly improved the microalgae growth rates and biomass amounts. Dry cell weight of eight strains up to 2.119–3.452 g·L−1 were achieved when ambient air containing 5% CO2 (v/v) and high light intensity were applied. The microalgal lipids contained fatty acid methyl esters mainly with C16:0, C18:1, C18:2, and C18:3, which were considered suitable for producing biodiesel.