Effects of nitrate and oxygen on photoautotrophic lipid production from Chlorococcum littorale.
Effects of oxygen and nitrate on fatty acid/lipid production from a highly CO(2)-tolerant microalgal species Chlorococcum littorale were examined under photoautotrophic conditions of 295 K, a light intensity of 170 μmol-photon m(-2) s(-1), a bubbling CO(2) concentration of 5% (v/v) and bubbling oxygen concentrations to be volumetrically adjusted by mixing oxygen gas with inert nitrogen gas at concentrations ranging from 0% to 95% (v/v). The results showed that maximum fatty acid content reached ca. 34 wt.% under oxygen-freely bubbling conditions and this value decreased to be ca. 20 wt.% when air-like oxygen concentration of 20% was chosen. This means that degree of the accumulation strongly depended on the level of bubbling oxygen concentrations, which can be a crucial factor after nitrogen depletion in the photoautotrophic culture system. TLC-FID/FPD analyses showed that triglycerides were found to be a dominant lipid class for this accumulation.
Research Center of Supercritical Fluid Technology, Tohoku University, Aoba-ku, Sendai, Japan.
Masaki
M
Ota
Yoshitaka
Y
Kato
Masaru
M
Watanabe
Yoshiyuki
Y
Sato
Richard L
RL
Smith
Rosa
R
Rosello-Sastre
Clemens
C
Posten
Hiroshi
H
Inomata
D000460:Chlorophyta / Q000187:drug effects / Q000502:physiology* / Q000528:radiation effects; D004305:Dose-Response Relationship, Drug; D008027:Light; D050356:Lipid Metabolism / Q000187:drug effects / Q000502:physiology* / Q000528:radiation effects; D009566:Nitrates / Q000008:administration & dosage*; D010100:Oxygen / Q000008:administration & dosage*; D010788:Photosynthesis / Q000187:drug effects / Q000502:physiology* / Q000528:radiation effects
D009566:Nitrates; D010100:Oxygen