Microbial Lipid Production from High Concentration of Volatile Fatty Acids via Trichosporon cutaneum for Biodiesel Preparation

作者：Liu, Juan; Zhou, Wenting; He, Qiaoning; Zhao, Man; Gong, Zhiwei^*

来源：Applied Biochemistry and Biotechnology - Part A Enzyme Engineering and Biotechnology, 2022, 194(7): 2968-2979.

DOI：10.1007/s12010-022-03903-x

• Volatile fatty acids
• Cytotoxic effect
• Microbial lipid
• Biodiesel
• Trichosporon cutaneum

Direct bioconversion of high concentration of volatile fatty acids (VFAs) into microbial lipid is challenging due to the aggravated cytotoxicity of VFAs at high loadings. Herein, a robust oleaginous yeast Trichosporon cutaneum was screened for lipogenesis from high concentration of VFAs using a regular batch culture. Biomass and lipid content of 8.9 g/L and 49.1%, respectively, were attained from 50 g/L acetic acid with 90.9% of which assimilated within 10 days. The blend of VFAs (50 g/L), with mass ratio of acetic, propionic, and butyric acids of 6:3:1, was found superior to acetic acid for lipogenesis. Biomass and lipid titer increased by 16.9% and 18.2%, respectively, with the three VFAs completely consumed within 8 days. Butyric acid was assimilated simultaneously with acetic acid at the beginning of the culture. Heptadecanoic acid (C17:0) and heptadecenoic acid (C17:1) were produced when propionic acid co-existed with acetic and butyric acids. The estimation of biodiesel properties indicated that lipid prepared from VFA blend showed superiority to acetic acid for high-quality biodiesel production. This study strongly supported that T. cutaneum permitted high concentration of VFA mixture for lipid production.