Effect of different cobalt (CoCl2) concentrations on cell growth, some biochemical composition, and fatty acids profile of the marine microalga, Tetraselmis subcordiformis

The aim of this study was to determine the effects of cobalt concentration on cell growth, some biochemical composition, and fatty acids profile of the marine microalga Tetraselmis subcordiformis. Cobalt deprivations did not cause a considerable change in growth photosynthesis activity as compared to the control group. Induction of maximum lipid production was achieved using 0.001 mg L-1 of cobalt-deprived T. subcordiformis. The highest crude protein content (33.75 mg L-1) was observed in 0.001 mg L-1 cobalt. The highest and lowest lipid accumulation in T. subcordiformis was observed in 0.001 mg L-1 and 10 mg L-1 cobalt, respectively. Under cobalt deficient conditions, T. subcordiformis produced a large quantity of saturated fatty acids and iodine and saponification value. Biodiesel characteristics were enhanced with Co+2 reduction. Also, biodiesel quality decreased with increase of cobalt. The results showed that the maximum and minimum carotenoids were observed in 0.1 and 10 mg L-1 cobalt, respectively.