Heterotrophic Omega-3 production in a novel microalga

Author: Tarandeep Kaur

Kaur, Tarandeep, 2021 Heterotrophic Omega-3 production in a novel microalga, Flinders University, College of Medicine and Public Health

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Omega-3 polyunsaturated fatty acids (Omega-3 PUFAs) are considered as essential compounds for human health and nutrition; thus, their demand is escalating. Traditionally, high-value PUFAs (DHA and EPA) are obtained from marine sources fish such as mackerel, salmon, and sardines. However, due to the metal accumulation in the fish oil and overfishing concerns therefore it is important to identify viable alternatives. Microalgae are highly recognized as a suitable platform for the production of omega-3 fatty acids. Moreover, Plants are also known to produce PUFAs but the quantities of PUFAs are not enough to meet market demand. Thus, the main aim of the study was to produce omega-3 fatty acids rich in DHA upon using an in-house heterotrophic microalgal strain S2 which is a thraustochytrid. Studies were conducted to improve omega-3 fatty acids proportions by optimizing various fermentation conditions. Various up-stream processing parameters such as alcohols, sodium salts, salts in the medium, glycerol concentrations, intermittent vs fixed carbon feeding, aeration, use of chemical modulators etc. were studied to achieve highest PUFAs yields. Maximum DHA content (44.23% of TFA) was obtained when carbon was fed at the concentration of 35 g/L at 72 h of fermentation, whereas the biomass recorded was 18.6 g/L, respectively. Strain S2 (thraustochytrid) was used for the first time for the production of omega-3 fatty acids. Thus, the study demonstrated heterotrophic production of omega-3 fatty acids thus achieving its objectives.

Keywords: Omega-3, Polyunsaturated fatty acids, eicosapentaenoic acid, docosahexaenoic acid, total fatty acids, microalga

Subject: Medical Biotechnology thesis

Thesis type: Masters
Completed: 2021
School: College of Medicine and Public Health
Supervisor: Associate Professor Munish Puri