Production of docosahexaenoic acid by a novel isolated Aurantiochytrium sp. 6-2 using fermented defatted soybean as a nitrogen source for sustainable fish feed development

• Published in: Bioscience, biotechnology, and biochemistry Vol. 88; no. 6; pp. 696 - 704
• Main Authors: Ip, Chi-Hei, Higuchi, Hibiki, Wu, Chang-Yu, Okuda, Tomoyo, Katsuya, Shohei, Ogawa, Jun, Ando, Akinori
• Format: Journal Article
• Language: English
• Published: England 22.05.2024
• Subjects: ω3-docosahexaenoic acid; Aurantiochytrium sp; fermented defatted soybean; plant biomass; polyunsaturated fatty acid
• ISSN: 1347-6947; 1347-6947
• DOI: 10.1093/bbb/zbae035

We focused on the production of docosahexaenoic acid (DHA)-containing microbial lipids by Aurantiochytrium sp. using of defatted soybean (DS) as a nitrogen source. Defatted soybean is a plant biomass that could provide a sustainable supply at a low cost. Results showed that Aurantiochytrium sp. could not directly assimilate the DS as a nitrogen source but could grow well in a medium containing DS fermented with rice malt. When cultivated in a fermented DS (FDS) medium, Aurantiochytrium sp. showed vigorous growth with the addition of sufficient sulfate and chloride ions as inorganic nutrients without seawater salt. A novel isolated Aurantiochytrium sp. 6-2 showed 15.8 ± 3.4 g/L DHA productivity (in 54.8 ± 12.1 g/L total fatty acid production) in 1 L of the FDS medium. Therefore, DHA produced by Aurantiochytrium sp. using FDS enables a stable and sustainable DHA supply and could be an alternative source of natural DHA derived from fish oil.