Optimization of cultivation conditions and characteristics of lipid accumulation of Chlorella sp.

In order to obtain the optimal cultivating and oil-producing parameters,the influence of NO3-N,Fe3+,Mg2+and Zn2+ concentrations on the growth of Chlorella sp.was explored.The Nile Red was used to examine the lipid content of Chlorella sp.at the same time.The factors affecting the growth and oil-production of Chlorella sp.were optimized by the orthogonal experimental design.Chlorella sp.showed the fast-growing under high concentration of NO3-N,Mg2+and Fe3+,while high Zn2+ inhibited its growth.The change of pH has little influence to its growth.It concluded that nitrogen limit and high concentration of Mg2+ or Fe3+ could improve the lipid content in Chlorella sp.The orthogonal experiment showed that the optimal cultivation condition was a group of factors containing 12 μmol/L Fe3+,7.2 μmol/L Zn2+ and 0.3 mmol/L NO3-N for Chlorella sp.