Improvement of culture conditions for cell biomass and fatty acid production by marine thraustochytrid F24-2

Abstract

Identification of fermentation parameters affecting biomass and total fatty acid (TFA) production by thraustochytrid F24-2 was conducted using a Plackett-Burman experimental design. Factors influencing biomass accumulation were initial pH, sea salts, and glucose concentration. Additionally, temperature, initial pH, soy peptone, glucose, and sea salt concentration affected TFA production. Docosapentaenoic acid (n-6 DPA), palmitic acid (C16:0), and docosahexaenoic acid (DHA) were the predominant fatty acids produced. The best biomass (10.71 ± 0.04 g L−1), TFA (2.11 ± 0.07 g L−1), DHA (0.92 ± 0.04 g L−1), and C16:0 (0.65 ± 0.02 g L−1) concentrations were obtained at 25 °C with a medium adjusted to pH 7 and containing (per liter): 20 g glucose, 20 g soy peptone, 18 g sea salts, 0.2 g ammonium sulfate, 3 μg vitamin B12, 3 μg biotin, and 0.6 mg thiamine hydrochloride. Under these conditions, DHA production increased 18.5% in comparison to a complex medium previously used to grow thraustochytrid Thraustochytrium aureum ATCC 34304.