title: [Effect of inorganic carbon source on lipid production with autotrophic Chlorella vulgaris].
abstract: We studied the effects of three inorganic carbon sources, Na2CO3, NaHCO3 and CO2, and their initial concentrations on lipid production of Chlorella vulgaris. Chlorella vulgaris could utilize Na2CO3, NaHCO3 and CO2 to produce lipids. After 10-day cultivation with each of the three inorganic carbon sources, lipid yield of Chlorella vulgaris reached its peak with the concentration increase of the inorganic carbon source, but dropped again by further increase of the concentration. The pH value of the culture medium for Chlorella vulgaris increased after the cultivation on inorganic carbon source. The optimal concentration of both Na2CO3 and NaHCO3 was 40 mmol/L, and their corresponding biomass dry weight was 0.52 g/L and 0.67 g/L with their corresponding lipid yield 0.19 g/L and 0.22 g/L. When the concentration of CO2 was 6%, Chlorella vulgaris grew the fastest and its biomass dry weight was 2.42 g/L with the highest lipid yield of 0.72 g/L. When the concentration of CO2 was too low, the supply of inorganic carbon was insufficient and lipid yield was low. A too high concentration of CO2 caused a low pH and lipid accumulation was inhibited. Na2CO3 and NaHCO3 were more favorable for Chlorella vulgaris to accumulate unsaturated fatty acids than that of CO2.
authors.affiliation: College of Biotechnology and Pharmaceutical Engineering, Nanjing University of Technology, Nanjing 210009, China.
authors.forename: Hongli
authors.initials: H
authors.lastname: Zheng
authors.forename: Zhen
authors.initials: Z
authors.lastname: Gao
authors.forename: Qi
authors.initials: Q
authors.lastname: Zhang
authors.forename: He
authors.initials: H
authors.lastname: Huang
authors.forename: Xiaojun
authors.initials: X
authors.lastname: Ji
authors.forename: Honglei
authors.initials: H
authors.lastname: Sun
authors.forename: Chang
authors.initials: C
authors.lastname: Dou
mesh_terms: D056804:Biofuels; D002244:Carbon / Q000378:metabolism*; D002245:Carbon Dioxide / Q000494:pharmacology*; D002254:Carbonates / Q000494:pharmacology; D048408:Chlorella vulgaris / Q000254:growth & development / Q000378:metabolism*; D003470:Culture Media; D046508:Culture Techniques / Q000379:methods; D008055:Lipids / Q000096:biosynthesis*; D017693:Sodium Bicarbonate / Q000494:pharmacology
chemical_list: D056804:Biofuels; D002254:Carbonates; D003470:Culture Media; D008055:Lipids; D002245:Carbon Dioxide; C005686:sodium carbonate; D002244:Carbon; D017693:Sodium Bicarbonate