A Novel Strain of <i>Aurantiochytrium</i> sp. Strain L3W and Its Characteristics of Biomass and Lipid Production Including Valuable Fatty Acids

Thraustochytrids such as Aurantiochytrium are heterotrophic and produce valuable fatty acids (FAs) and therefore expected as a tool for removal of organic compounds in wastewater and simultaneous production of FAs. The four strains of Aurantiochytrium sp. were isolated from the mangrove leaf samples, and among these the strain L3W showed the high specific growth rate of 0.27 1/h at 25°C. In addition, this strain grew at the ranges of temperature from 15°C to 35°C, pH from 3 to 9, and salinity from 0.3 to 70 PSU. Under the optimal condition of 25°C, 30 PSU, and pH7, the strain L3W produced 270 mg/g of FAs including 135 mg/g of docosahexaenoic acid, 11 mg/g of pentadecanoic acid and 9.3 mg/g of margaric acid. Furthermore, the strain L3W produced these FAs at pH3 and pH9. The pH and salinity tolerance of the strain L3W might be advantageous in its application for production of valuable FAs under competition with other microorganisms in unsterile wastewater.