Growth and lipid accumulation properties of microalgal Phaeodactylum tricornutum under different gas liquid ratios

In this study, the effects of gas liquid ratio (GLR) on growth, lipid and fatty acid production of Phaeodactylum tricornutum were investigated. The positive linear relationships among specific growth rate, lipid content, fatty acid methyl ester content and GLR were built. GLR of 1.5 vvm was considered as the optimum GLR for P. tricornutum growth and yielding oil, with highest biomass productivity (227.09 mg L−1 d−1), highest lipid productivity (48.48 mg L−1 d−1) and considerable amount fatty acids of saturated (50.16%) and monounsaturated (48.79%), which gave the finest compromise between oxidative stability and cold flow properties. pH variation was good controlled by the air bubbling velocity and algal photosynthesis. CO32−/HCO3− ratio influenced the fatty acids synthesis, especially the component of C16:1. The average value of the most favorable composition C16:1 was 48.36%, which is comparable with other reports.