Characterization of Omega-3 and Omega-6 Fatty Acid Accumulation in Chlorococcum novae-angliae Microalgae Grown under Various Culture Conditions

Abstract

Chlorococcum novae-angliae is a terrestrial green microalgae species with remarkable potential to synthesize omega-3 (ω-3) and omega-6 (ω-6) fatty acids. In this study, Chlorococcum novae-angliae has been subjected to varying growth conditions (light, nitrogen, salinity, and temperature) to investigate the accumulation of ω-3 and ω-6 fatty acids. Among tested growth conditions, eicosapentaenoic acid, α-linoleic acid, γ-linoleic acid, and arachidonic acid were enhanced by nitrogen limitation. Significant increases were observed in concentration of linoleic acid, an essential precursor molecule for the production ω-6 fatty acids under decreased nitrogen concentrations. Despite the lowest biomass growth, monounsaturated fatty acids and docosahexaenoic acid were increased by 14.4% and 8.7% under low light intensities, respectively. Meanwhile, the highest concentrations of palmitic acid (C16:0), stearic acid (C18:0), and oleic acid (18:1cis-9) were also detected under nitrogen limitation. Total lowest fatty acid concentrations were obtained under increased salinity while low temperature conditions heavily inhibited cellular growth.

Keywords

• Chlorococcum novae-angliae
• essential fatty acids
• microalgal lipids
• omega fatty acids

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