Nitrogen Sources Affect the Long-Chain Polyunsaturated Fatty Acids Content in Thraustochytrium sp. RT2316-16

• Published in: Marine drugs 2022-12, Vol.21 (1), p.15
• Main Authors: Valdebenito, Diego, Urrutia, Sebastián, Leyton, Allison, Chisti, Yusuf, Asenjo, Juan A, Shene, Carolina
• Format: Article
• Language: English
• Subjects: Alanine; Amino acids; Ammonium; Ammonium compounds; Biomass; Carotenoids; Carotenoids - metabolism; Culture media; Docosahexaenoic acid; Docosahexaenoic Acids - metabolism; Eicosapentaenoic acid; Eicosapentaenoic Acid - metabolism; Experiments; Fatty acids; Fatty Acids - metabolism; Fatty Acids, Omega-3 - metabolism; Glucose; Glucose - metabolism; Glutamates - metabolism; Lipid metabolism; Lipids; Lysine; Marine microorganisms; Metabolism; microbial lipids; Nitrogen; Nitrogen - metabolism; Nitrogen sources; omega-3 polyunsaturated fatty acids; Organic nitrogen; Polyunsaturated fatty acids; Serine; Stramenopiles - metabolism; Thraustochytrium; Thraustochytrium sp; Yeast; Yeasts
• ISSN: 1660-3397; 1660-3397
• DOI: 10.3390/md21010015

The psychrophilic marine microorganism sp. RT2316-16 can produce carotenoids as well as lipids containing the omega-3 polyunsaturated fatty acids (PUFA) eicosapentaenoic acid and docosahexaenoic acid. This work reports on the effects of the composition of the culture medium, including certain amino acids, on growth and lipid synthesis by RT2316-16. Compared with the culture on glutamate, the use of lysine, alanine, or serine, increased the content of the omega-3 PUFA in total lipids. In the media that contained yeast extract, glutamate, and glucose, lipid accumulation occurred when organic ammonium was exhausted earlier than glucose. In contrast, lipid mobilization was promoted if glucose was exhausted while organic ammonium (supplied by yeast extract and glutamate) remained in the medium. The total content of carotenoids in the lipid-free biomass decreased during the first 12 to 24 h of culture, simultaneously with a decrease in the total lipid content of the biomass. The experimental data suggested a possible interrelationship between the metabolism of carotenoids and lipids. A high content of omega-3 PUFA in the total lipids could be obtained by growing the thraustochytrid in a medium with a low glucose concentration (6 g L ) and a high concentration of organic nitrogen (yeast extract 12 g L ; glutamate 1.06 g L ), after glucose was exhausted. These observations may guide the development of a strategy to enhance omega-3 PUFA in the biomass.