Transformation of triolein to biogasoline by photo-chemo-biocatalysis

Abstract

The development of biomass energy obtained from nonfossil and renewable feedstocks is an important means to deal with the fossil energy crisis. The preparation of gasoline-range bio-hydrocarbons from natural abundant and renewable lipids has high potential. However, it is much more difficult than the preparation of widely reported biodiesel and represents a challenge to green chemistry. Compared with traditional methods usually involving harsh reaction conditions, a photo-chemo-enzymatic multi-step combination route was developed in this study for the highly efficient and environment-friendly preparation of biogasoline from cheap and sustainable triolein using solar energy and atmospheric O₂ under mild conditions. This whole catalytic sequence was composed of lipase-catalyzed hydrolysis of triolein, fatty acid photodecarboxylase (CvFAP)-catalyzed decarboxylation of oleic acid, photocatalytic oxidative cleavage of long-chain alkene, and the final decarboxylation of the medium- or short-chain fatty acids catalyzed by CvFAP mutant. After optimizing the reaction conditions in detail, the practicability of the method was proved by a gram-scale experiment. This protocol was successfully applied to the conversion of various long-chain unsaturated acids and long-chain alkenes into biogasoline, implying its wide substrate scope. This photo-chemo-biocatalytic sequential reaction exhibited great potential to generate high value-added gasoline alkanes from natural abundant lipids and even wasted or non-edible oil.