title: [Effects of carbon source and concentration on the growth density, lipid accumulation and fatty acid composition of Nannochloropis oculata].
abstract: Effects of carbon sources (Na2CO3, NaHCO3 and glucose) and concentration of NaHCO3 on the growth density and lipid contents of Nannochloropsis oculata were studied. N. oculata preferred inorganic carbon to glucose, the growth density and lipid content of algae cultured with NaHCO3 were higher than that with glucose. The effects of concentration of NaHCO3 on growth density and lipid content were related to inoculation density and nitrogen level. In high nitrogen level, the concentration of NaHCO3 had little effect on the growth density, but in low nitrogen level, the growth density increased at first, and then decreased with the increase of concentration of NaHCO3. Based on the results we suggest that an optimum ratio of carbon to nitrogen was existed. Furthermore, we found the optimum ratio was changed with inoculation density. The optimum ratio of carbon to nitrogen was 3 when inoculation density was OD440 of 0.10, the optimum ratio increased to 5 with OD440 of 0.70. Concentration of NaHCO3 and ratio of carbon to nitrogen had significant effects on the lipid content and productivity. Lipid content reached the highest value when the ratio of carbon to nitrogen was 1 with experimental range of nitrogen level and inoculation density. The lipid productivity was 56.7 mg/(L.d) , and the EPA productivity was 6.5 mg/(L.d) at optimum cultivation condition with NaHCO3 as carbon source, the ratio of carbon to nitrogen at 1, the concentration of NaNO3 at 0.225 g/L, and the inoculation density with OD440 of 0.70.
authors.affiliation: Zhejiang Province Key Laboratory of Biofuel, College of Chemical Engineering and Materials Science, Zhejiang University of Technology, Hangzhou 310014, Zhejiang, China.
authors.forename: Xiao
authors.initials: X
authors.lastname: Dou
authors.forename: Xianghong
authors.initials: X
authors.lastname: Lu
authors.forename: Meizhen
authors.initials: M
authors.lastname: Lu
authors.forename: Rong
authors.initials: R
authors.lastname: Xue
authors.forename: Rongjun
authors.initials: R
authors.lastname: Yan
authors.forename: Jianbing
authors.initials: J
authors.lastname: Ji
mesh_terms: D002244:Carbon / Q000737:chemistry / Q000378:metabolism*; D003470:Culture Media; D046508:Culture Techniques / Q000379:methods; D005227:Fatty Acids / Q000378:metabolism*; D005285:Fermentation; D005947:Glucose / Q000378:metabolism; D050356:Lipid Metabolism; D058086:Microalgae / Q000254:growth & development / Q000378:metabolism*; D011156:Population Density; D058009:Stramenopiles / Q000254:growth & development / Q000378:metabolism*
chemical_list: D003470:Culture Media; D005227:Fatty Acids; D002244:Carbon; D005947:Glucose