Enhanced Fermentation Process for Production of High Docosahexaenoic Acid Content by Schizochytrium sp. GCD2032

Abstract

There is significant demand for high-purity DHA in the pharmaceutical industry. Traditionally, this high-purity DHA is extracted from raw materials with relatively low DHA content (10–20%), such as fish oil. Recently, through electroporation-induced mutation, a high-DHA-content strain of Schizochytrium sp. GCD2032 was isolated. To further enhance its DHA production, optimizations were conducted on the culture medium and fermentation conditions (in shaking flasks), as well as different nitrogen source concentrations (in a 5 L fermenter) for biomass, fatty acid content, and DHA content (as a percentage of total fatty acids). In a 5 L fermenter, Schizochytrium sp. GCD2032 achieved a biomass of 50 g/L, with fatty acid content of 55.71% and DHA content of 61.29%. Notably, the DHA content reached an impressive 341.45 mg/g of dry weight. This strain consistently produces high levels of fatty acids and DHA, demonstrating significant potential for pharmaceutical applications.