TY - JOUR
T1 - Effects of light intensity and carbon dioxide on lipids and fatty acids produced by Synechocystis sp. PCC6803 during continuous flow
AU - Cuellar-Bermudez, Sara P.
AU - Romero-Ogawa, Miguel A.
AU - Vannela, Raveender
AU - Lai, YenJung Sean
AU - Rittmann, Bruce
AU - Parra-Saldivar, Roberto
N1 - Publisher Copyright:
© 2015 The Authors. Published by Elsevier B.V.
PY - 2015/11/1
Y1 - 2015/11/1
N2 - We studied the effects of light intensity (LI) and CO2 supply on pH and total lipid production and fatty acids by Synechocystis sp. PCC6803 during continuous-flow operation of a photobioreactor having continuous nutrient supply. The temperature was fixed at 30 °C, and the LI pattern mimicked a day/night light cycle from 0 to 1920 μmol/m2 s. The CO2 supply varied from1 to 5% v/v of total air. The total lipid content increased proportionally to LI, reaching a high content of 14% of dry weight (DW) at the highest LI at 3% CO2. In contrast, LI had no significant influence on the total fatty acid content, which was 3.4% ± 0.5% DW, measured as fatty acid methyl esters (FAMEs). Palmitic acid (C16:0) was the main fatty acid (52% of FAMEs), but γ-linolenic acid (C18:3n6) and linoleic acid (C18:2) were significant at 20% and 14% of total FAMEs, respectively. Also, a-linolenic acid (C18:3n3), oleic acid (C18:1), and palmitoleic acid (C16:1) represented 5%, 4%, and 4% of the total FAMEs, respectively. In case of C16:0, its highest content was achieved at LI of 400 to 1500 μmol/m2 s and pH media values from 7.2 to 8.8 (3% CO2). The highest formation of C16:1 and C18:1 (desirable for biodiesel production) occurred with LI up to 600 μmol/m2 s at pH 9 (3% CO2). Stearic acid (C18:0) and linoleic acid (C18:2) contents did not vary with LI or pH, but α-linolenic acid (C18:3n3) formation occurred with patterns opposite to C18:3n6, C16:0, and C16:1. LI of 400 to 1600 μmol/m2 s and pH range from 7.7 to 8.7 led to the highest values of C18:3n6 (0.8% DW), but C18:3n3 was suppressed by these conditions, supporting a desaturation pathway in Synechocystis. These results point to strategies to optimize LI, CO2, and pH, to enhance the fatty acid production profile for biofuel production.
AB - We studied the effects of light intensity (LI) and CO2 supply on pH and total lipid production and fatty acids by Synechocystis sp. PCC6803 during continuous-flow operation of a photobioreactor having continuous nutrient supply. The temperature was fixed at 30 °C, and the LI pattern mimicked a day/night light cycle from 0 to 1920 μmol/m2 s. The CO2 supply varied from1 to 5% v/v of total air. The total lipid content increased proportionally to LI, reaching a high content of 14% of dry weight (DW) at the highest LI at 3% CO2. In contrast, LI had no significant influence on the total fatty acid content, which was 3.4% ± 0.5% DW, measured as fatty acid methyl esters (FAMEs). Palmitic acid (C16:0) was the main fatty acid (52% of FAMEs), but γ-linolenic acid (C18:3n6) and linoleic acid (C18:2) were significant at 20% and 14% of total FAMEs, respectively. Also, a-linolenic acid (C18:3n3), oleic acid (C18:1), and palmitoleic acid (C16:1) represented 5%, 4%, and 4% of the total FAMEs, respectively. In case of C16:0, its highest content was achieved at LI of 400 to 1500 μmol/m2 s and pH media values from 7.2 to 8.8 (3% CO2). The highest formation of C16:1 and C18:1 (desirable for biodiesel production) occurred with LI up to 600 μmol/m2 s at pH 9 (3% CO2). Stearic acid (C18:0) and linoleic acid (C18:2) contents did not vary with LI or pH, but α-linolenic acid (C18:3n3) formation occurred with patterns opposite to C18:3n6, C16:0, and C16:1. LI of 400 to 1600 μmol/m2 s and pH range from 7.7 to 8.7 led to the highest values of C18:3n6 (0.8% DW), but C18:3n3 was suppressed by these conditions, supporting a desaturation pathway in Synechocystis. These results point to strategies to optimize LI, CO2, and pH, to enhance the fatty acid production profile for biofuel production.
KW - CO
KW - Fatty acids
KW - Light intensity
KW - Lipids
KW - Synechocystis
KW - pH
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U2 - 10.1016/j.algal.2015.07.018
DO - 10.1016/j.algal.2015.07.018
M3 - Article
AN - SCOPUS:84947945110
SN - 2211-9264
VL - 12
SP - 10
EP - 16
JO - Algal Research
JF - Algal Research
ER -