Bioprocessing of Biomass Derived Lignin to Fatty Acids

A DOE recently funded research team has developed microbial technology that is capable of converting lignin to lipids for biofuel production. In this study, a series of alkaliphilic and halotolerant bacteria (e.g. Bacillus ligniphilus, Rhodococcus jostii RHA1, and Rhodococcos opacus) with strong lignin degradation and/or fatty acid biosynthesis capacities were selected to establish the functional modules to enable a platform for efficient conversion of lignin to fatty acids. The key challenge is to apply lignin degradation microorganisms that depolymerize lignin to reactive intermediates (e.g. 4-hydroxybenzoic acid, vanillic acid) for oleaginous bacteria to produce lipids. A set of optimized parameters for each particular strain for lignin degradation and/or lipid yield using different technical lignins as the sole carbon source was investigated. We believe that the integration of a lignin deploymerzation strain with a fatty acid-producing microorganism will enable utilizing biomass derived lignin to generate fatty acid-- a major step towards biodiesel fuels.