Zhang Yingqiu, E Jiawei, Chen Cheng, Wei Kaixin, Sun Liyun, Tan Gaoyi, Zhang Xu, Fan Jianhua
State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai 200237, PR China.
Department of Applied Biology, East China University of Science and Technology, Shanghai 200237, PR China.
Bioresour Technol. 2025 Oct;434:132780. doi: 10.1016/j.biortech.2025.132780. Epub 2025 Jun 7.
Dark fermentation wastewater, often rich in volatile fatty acids (VFAs), presents significant treatment challenges but also holds potential value. Oil-producing microorganisms can efficiently convert high VFAs concentrations into intracellular lipids. This study explores how VFAs utilization by Schizochytrium limacinum SR21 affects microbial fatty acid accumulation. It was found that S. limacinum has high VFAs biotransformation ability. The results show that butyric acid, as the sole carbon source, significantly enhances S. limacinum SR21 growth and docosahexaenoic acid (DHA) production, with utilization rate of 100 % and DHA yields of 2.0 g/L under optimal conditions. In actual wastewater applications, DHA production reached 1.5 g/L, with total phosphorus and chemical oxygen demand (COD) removal efficiencies of 41.2 % and 52.7 %, respectively. This approach not only addresses the treatment of dark fermentation wastewater but also enables polyunsaturated fatty acids (PUFAs) production from accumulated lipids, supporting both environmental and energy sustainability.
