Fig. 5

Extractable lipid class and FAME profiles for cultures of C. vulgaris when cultured under various inorganic carbon regimes. Experimental conditions: (1) the optimized scenario of a continuous sparge of atmospheric air supplemented periodically with 5 % CO₂ (v/v) to maintain pH between 8.4 and 8.7 and an initial addition of 5 mM NaHCO₃ at inoculation plus an additional 50 mM of ACS grade NaHCO₃ just prior to nitrogen depletion to stimulate TAG accumulation. (2) The same culture conditions as scenario 1 listed above, except TAG accumulation was induced by adding 25 mM NaHCO₃∙Na₂CO₃ (sesquicarbonate). (3) Continuous sparge of atmospheric air supplemented with 5 % CO₂ (v/v) during daytime hours. Values are reported for the completion of the experiment (n = 3). All values expressed as weight percent (% weight extractable lipid or weight FAME/weight biomass)