Microbial lipid synthesis based on visible light-driven oxygen doped-graphitic carbon nitride /oleaginous yeast hybrid system

Abstract

The use of solar energy and heterotrophic microbes to synthesize microbial lipids is a promising strategy to solve energy crisis and reduce CO₂ emissions. In this study, a photocatalyst, oxygen-doped graphitic carbon nitride (O-g-C₃N₄), was synthesized and combined with an oleaginous yeast strain, Cutaneotrichosporon dermatis ZZ-46, to construct a photocatalyst-microbe hybrid (PMH) system. Under illumination, the lipid yield of the PMH system reached 1.61 g/L after 96 h (87 % higher than that of control). NADPH/NADP⁺ ratio of ZZ-46 cells in the PMH system increased. Metabolomics results revealed that glutathione generation was increased, and the fatty acid decomposition pathway in ZZ-46 cells was inhibited in the PMH system. This study provides a new approach for the synthesis of microbial lipids based on solar energy and heterotrophic microbes.

Keywords: Biofuel; NADPH generation; Photocatalyst-microbe hybrid; Solar-to-chemical conversion.