Effects of Fed-batch Cultivation and Nitrogen Deficiency on Lipid Yield of Chlorella vulgaris

[Objective] To achieve high yield of biomass and lipid of Chlorella vulgaris.[Method] The growth curve of C.vulgaris,variation curves of residual glucose concentration,pH,dissolved oxygen of the medium during batch cultivation were analyzed to culture C.vulgaris accordingly by fed-batch until certain density,and then the C.vulgaris was cultured with deficient nitrogen to enrich the lipid.[Result] After fed-batch cultivation for four times,the biomass yield of C.vulgaris reached 65.25 g/L,then cultured by nitrogen deficiency for another 12 hours,the lipid content was improved from 42.75% to 63.82%,and the lipid yield reached 43.37 g/L.[Conclusion] Reasonable fed-batch culture greatly improves the biomass of C.vulgaris,while the cultivation by nitrogen deficiency further increases its lipid content.