The aim of this study was to investigate the growth, lipid content and lipid productivity of the biodiesel
promising microalgae Scenedesmus obliquus and Micractinium reisseri grown in batch culture using four different
freshwater growth media, namely Chu-10, KC, Flory and Kuhl's medium to identify the most suitable medium for high lipid
production for each species. The Results confirmed that Kuhl and KC showed the highest biomass productivity for S.
obliquus and M. reisseri (0.05 and 0.07g L-1 d-1, respectively). The Lipid content and lipid productivity were estimated at
four different growth phases (early, middle, late exponential and stationary phase).The results revealed that, M. reisseri
showed the highest lipid productivity at stationary phase (17.08 mg L−1d−1), while S. obliquus showed lipid productivity of
12.61 mg L−1d−1 which was insignificant with that at the late exponential phase (12.55 mg L−1d−1). The fatty acids profile of
S. obliquus and M. reisseri at stationary growth phase showed that both of them were suitable as feedstock for biodiesel
production because of their high saturated fatty acids content that represented by 81.34% and 72.51% of the total fatty
content, respectively. Palmitic acid (C16:0) was represented by 15.74 and 16.06 % in the two studied species, respectively
that increase the biodiesel quality for each strain. This study suggests M. reisseri cultivated on KC medium to provide high
lipid productivity which offers a promise to be one of the sources of biodiesel.