2. Materials and methods
2.1. Strains and preculture conditions
Four species of microalgae, I. galbana, N. oculata, D. salina, and D. tertiolecta, were obtained from NLP Corp. (Busan, Korea). After preculture in a 1-L flask, the microalgae were cultivated at 20 ± 1 C at a light intensity of 108.9 mmol photon/m2/s in a 5-L circular cylindrical
photobioreactor with a working volume of 3 L using f/2 medium, as described by Guillard and Ryther [20]. Aeration with filtered air was provided through an air stone at a rate of 2.5 L/min.
All cultures were carried out with a 12/12-h light/dark cycle.