The Effect of Nutrients Concentration and Light Intensity on the Growth and Density of the economic Microalgae Chlorella vulgaris

The effects of nutrients and light intensity fluctuations in different formulations of TMRL medium on growth and density of Chlorella vulgaris microalgae were investigated within the shortest time to obtain highest density. TMRL medium was provided with different densities of nitrogen (30, 50, and 70 gr), phosphorus (3, 5, and 7 gr), and fixed iron content (1 gr of FeCl3). The Microalgae were cultured in 2 light intensities (3500±350 lux) and (550 ± 350 lux). A total of six treatments with three replications were considered and the samples were counted 6 times within 12 days. An equal number of Chlorella vulgaris microalgae cells were injected to the treatments (15×105 cells/ml). Based on the results, the highest growth of Chlorella vulgaris obtained in the medium containing 5 g of phosphorus, 50 g of nitrogen (Urea), and 1 g of iron in light density of 3500 lux in the 12th day (p<0.05). Meanwhile, protein, fat, carbohydrate, and minerals components were 45.2, 9.5, 25.1, and 9.1 percent respectively in dry weight of the microalgae.