Effects of changing nitrogen sources on lipid content of Chlorella vulgaris C95

The effects of different nitrogen sources on the growth and oil accumulation of Chlorella vulgaris were studied and the optimum nitrogen source was obtained. Meanwhile,the growth,oil accumulation,nitrogen consumption,cell yield coefficient to nitrogen and lipid yield coefficient to nitrogen under the conditions of nitrogen cultivation and nitrogen starvation cultivation were compared and analyzed. The results showed that the maximum biomass was obtained at 1. 6 g / L Na NO3 and the maximum lipid accumulation was obtained at 0. 8 g / L Na NO3; the optimal nitrogen source of Chlorella type and its concentration was 0. 8 g / L Na NO3. Under the condition of nitrogen starvation cultivation,cultivate chlorella in stages of oil content was 13. 49%,increased 15% if compared with that of the nitrogen training; the highest biomass was 626. 3 mg / L under single step training,about 1. 9 times higher than that of the nitrogen starvation cultivation. These results collectively suggested that nitrogen sources could obviously affect the biomass,oil content,cell yield coefficient to nitrogen and lipid yield coefficient to nitrogen. Therefore,nitrogen source could be modified to regulate physiological metabolism during the cultivation of Chlorella vulgaris.